Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

316 files changed, 65359 insertions, 0 deletions

diff --git a/toolkit/components/passwordmgr/CSV.sys.mjs b/toolkit/components/passwordmgr/CSV.sys.mjs
new file mode 100644
index 0000000000..ef5e78c232
--- /dev/null
+++ b/toolkit/components/passwordmgr/CSV.sys.mjs
@@ -0,0 +1,122 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * A Class to parse CSV files
+ */
+
+const QUOTATION_MARK = '"';
+const LINE_BREAKS = ["\r", "\n"];
+const EOL = {};
+
+class ParsingFailedException extends Error {
+  constructor(message) {
+    super(message ? message : `Stopped parsing because of wrong csv format`);
+  }
+}
+
+export class CSV {
+  /**
+   * Parses a csv formated string into rows split into [headerLine, parsedLines].
+   * The csv string format has to follow RFC 4180, otherwise the parsing process is stopped and a ParsingFailedException is thrown, e.g.:
+   * (wrong format => right format):
+   * 'abc"def' => 'abc""def'
+   * abc,def => "abc,def"
+   *
+   * @param {string} text
+   * @param {string} delimiter a comma for CSV files and a tab for TSV files
+   * @returns {Array[]} headerLine: column names (first line of text), parsedLines: Array of Login Objects with column name as properties and login data as values.
+   */
+  static parse(text, delimiter) {
+    let headerline = [];
+    let parsedLines = [];
+
+    for (let row of this.mapValuesToRows(this.readCSV(text, delimiter))) {
+      if (!headerline.length) {
+        headerline = row;
+      } else {
+        let login = {};
+        row.forEach((attr, i) => (login[headerline[i]] = attr));
+        parsedLines.push(login);
+      }
+    }
+    return [headerline, parsedLines];
+  }
+  static *readCSV(text, delimiter) {
+    function maySkipMultipleLineBreaks() {
+      while (LINE_BREAKS.includes(text[current])) {
+        current++;
+      }
+    }
+    function readUntilSingleQuote() {
+      const start = ++current;
+      while (current < text.length) {
+        if (text[current] === QUOTATION_MARK) {
+          if (text[current + 1] !== QUOTATION_MARK) {
+            const result = text.slice(start, current).replaceAll('""', '"');
+            current++;
+            return result;
+          }
+          current++;
+        }
+        current++;
+      }
+      throw new ParsingFailedException();
+    }
+    function readUntilDelimiterOrNewLine() {
+      const start = current;
+      while (current < text.length) {
+        if (text[current] === delimiter) {
+          const result = text.slice(start, current);
+          current++;
+          return result;
+        } else if (LINE_BREAKS.includes(text[current])) {
+          const result = text.slice(start, current);
+          return result;
+        }
+        current++;
+      }
+      return text.slice(start);
+    }
+    let current = 0;
+    maySkipMultipleLineBreaks();
+
+    while (current < text.length) {
+      if (LINE_BREAKS.includes(text[current])) {
+        maySkipMultipleLineBreaks();
+        yield EOL;
+      }
+
+      let quotedValue = "";
+      let value = "";
+
+      if (text[current] === QUOTATION_MARK) {
+        quotedValue = readUntilSingleQuote();
+      }
+
+      value = readUntilDelimiterOrNewLine();
+
+      if (quotedValue && value) {
+        throw new ParsingFailedException();
+      }
+
+      yield quotedValue ? quotedValue : value;
+    }
+  }
+
+  static *mapValuesToRows(values) {
+    let row = [];
+    for (const value of values) {
+      if (value === EOL) {
+        yield row;
+        row = [];
+      } else {
+        row.push(value);
+      }
+    }
+    if (!(row.length === 1 && row[0] === "") && row.length) {
+      yield row;
+    }
+  }
+}
diff --git a/toolkit/components/passwordmgr/InsecurePasswordUtils.sys.mjs b/toolkit/components/passwordmgr/InsecurePasswordUtils.sys.mjs
new file mode 100644
index 0000000000..5d1bb2bf19
--- /dev/null
+++ b/toolkit/components/passwordmgr/InsecurePasswordUtils.sys.mjs
@@ -0,0 +1,214 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* ownerGlobal doesn't exist in content privileged windows. */
+/* eslint-disable mozilla/use-ownerGlobal */
+
+const STRINGS_URI = "chrome://global/locale/security/security.properties";
+
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+});
+
+ChromeUtils.defineLazyGetter(lazy, "log", () => {
+  return lazy.LoginHelper.createLogger("InsecurePasswordUtils");
+});
+
+/*
+ * A module that provides utility functions for form security.
+ *
+ */
+export const InsecurePasswordUtils = {
+  _formRootsWarned: new WeakMap(),
+
+  /**
+   * Gets the ID of the inner window of this DOM window.
+   *
+   * @param nsIDOMWindow window
+   * @return integer
+   *         Inner ID for the given window.
+   */
+  _getInnerWindowId(window) {
+    return window.windowGlobalChild.innerWindowId;
+  },
+
+  _sendWebConsoleMessage(messageTag, domDoc) {
+    let windowId = this._getInnerWindowId(domDoc.defaultView);
+    let category = "Insecure Password Field";
+    // All web console messages are warnings for now.
+    let flag = Ci.nsIScriptError.warningFlag;
+    let bundle = Services.strings.createBundle(STRINGS_URI);
+    let message = bundle.GetStringFromName(messageTag);
+    let consoleMsg = Cc["@mozilla.org/scripterror;1"].createInstance(
+      Ci.nsIScriptError
+    );
+    consoleMsg.initWithWindowID(
+      message,
+      domDoc.location.href,
+      0,
+      0,
+      0,
+      flag,
+      category,
+      windowId
+    );
+
+    Services.console.logMessage(consoleMsg);
+  },
+
+  /**
+   * Gets the security state of the passed form.
+   *
+   * @param {FormLike} aForm A form-like object. @See {FormLikeFactory}
+   *
+   * @returns {Object} An object with the following boolean values:
+   *  isFormSubmitHTTP: if the submit action is an http:// URL
+   *  isFormSubmitSecure: if the submit action URL is secure,
+   *    either because it is HTTPS or because its origin is considered trustworthy
+   */
+  _checkFormSecurity(aForm) {
+    let isFormSubmitHTTP = false,
+      isFormSubmitSecure = false;
+    if (HTMLFormElement.isInstance(aForm.rootElement)) {
+      let uri = Services.io.newURI(
+        aForm.rootElement.action || aForm.rootElement.baseURI
+      );
+      let principal = Services.scriptSecurityManager.createContentPrincipal(
+        uri,
+        {}
+      );
+
+      if (uri.schemeIs("http")) {
+        isFormSubmitHTTP = true;
+        if (
+          principal.isOriginPotentiallyTrustworthy ||
+          // Ignore sites with local IP addresses pointing to local forms.
+          (this._isPrincipalForLocalIPAddress(
+            aForm.rootElement.nodePrincipal
+          ) &&
+            this._isPrincipalForLocalIPAddress(principal))
+        ) {
+          isFormSubmitSecure = true;
+        }
+      } else {
+        isFormSubmitSecure = true;
+      }
+    }
+
+    return { isFormSubmitHTTP, isFormSubmitSecure };
+  },
+
+  _isPrincipalForLocalIPAddress(aPrincipal) {
+    let res = aPrincipal.isLocalIpAddress;
+    if (res) {
+      lazy.log.debug(
+        "hasInsecureLoginForms: detected local IP address:",
+        aPrincipal.asciispec
+      );
+    }
+    return res;
+  },
+
+  /**s
+   * Checks if there are insecure password fields present on the form's document
+   * i.e. passwords inside forms with http action, inside iframes with http src,
+   * or on insecure web pages.
+   *
+   * @param {FormLike} aForm A form-like object. @See {LoginFormFactory}
+   * @return {boolean} whether the form is secure
+   */
+  isFormSecure(aForm) {
+    let isSafePage = aForm.ownerDocument.defaultView.isSecureContext;
+
+    // Ignore insecure documents with URLs that are local IP addresses.
+    // This is done because the vast majority of routers and other devices
+    // on the network do not use HTTPS, making this warning show up almost
+    // constantly on local connections, which annoys users and hurts our cause.
+    if (!isSafePage && this._ignoreLocalIPAddress) {
+      let isLocalIP = this._isPrincipalForLocalIPAddress(
+        aForm.rootElement.nodePrincipal
+      );
+
+      let topIsLocalIP =
+        aForm.ownerDocument.defaultView.windowGlobalChild.windowContext
+          .topWindowContext.isLocalIP;
+
+      // Only consider the page safe if the top window has a local IP address
+      // and, if this is an iframe, the iframe also has a local IP address.
+      if (isLocalIP && topIsLocalIP) {
+        isSafePage = true;
+      }
+    }
+
+    let { isFormSubmitSecure, isFormSubmitHTTP } =
+      this._checkFormSecurity(aForm);
+
+    return isSafePage && (isFormSubmitSecure || !isFormSubmitHTTP);
+  },
+
+  /**
+   * Report insecure password fields in a form to the web console to warn developers.
+   *
+   * @param {FormLike} aForm A form-like object. @See {FormLikeFactory}
+   */
+  reportInsecurePasswords(aForm) {
+    if (
+      this._formRootsWarned.has(aForm.rootElement) ||
+      this._formRootsWarned.get(aForm.rootElement)
+    ) {
+      return;
+    }
+
+    let domDoc = aForm.ownerDocument;
+    let isSafePage = domDoc.defaultView.isSecureContext;
+
+    let { isFormSubmitHTTP, isFormSubmitSecure } =
+      this._checkFormSecurity(aForm);
+
+    if (!isSafePage) {
+      if (domDoc.defaultView == domDoc.defaultView.parent) {
+        this._sendWebConsoleMessage("InsecurePasswordsPresentOnPage", domDoc);
+      } else {
+        this._sendWebConsoleMessage("InsecurePasswordsPresentOnIframe", domDoc);
+      }
+      this._formRootsWarned.set(aForm.rootElement, true);
+    } else if (isFormSubmitHTTP && !isFormSubmitSecure) {
+      this._sendWebConsoleMessage("InsecureFormActionPasswordsPresent", domDoc);
+      this._formRootsWarned.set(aForm.rootElement, true);
+    }
+
+    // The safety of a password field determined by the form action and the page protocol
+    let passwordSafety;
+    if (isSafePage) {
+      if (isFormSubmitSecure) {
+        passwordSafety = 0;
+      } else if (isFormSubmitHTTP) {
+        passwordSafety = 1;
+      } else {
+        passwordSafety = 2;
+      }
+    } else if (isFormSubmitSecure) {
+      passwordSafety = 3;
+    } else if (isFormSubmitHTTP) {
+      passwordSafety = 4;
+    } else {
+      passwordSafety = 5;
+    }
+
+    Services.telemetry
+      .getHistogramById("PWMGR_LOGIN_PAGE_SAFETY")
+      .add(passwordSafety);
+  },
+};
+
+XPCOMUtils.defineLazyPreferenceGetter(
+  InsecurePasswordUtils,
+  "_ignoreLocalIPAddress",
+  "security.insecure_field_warning.ignore_local_ip_address",
+  true
+);
diff --git a/toolkit/components/passwordmgr/LoginAutoComplete.sys.mjs b/toolkit/components/passwordmgr/LoginAutoComplete.sys.mjs
new file mode 100644
index 0000000000..6ff96d999e
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginAutoComplete.sys.mjs
@@ -0,0 +1,773 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * nsIAutoCompleteResult and nsILoginAutoCompleteSearch implementations for saved logins.
+ */
+
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+import { GenericAutocompleteItem } from "resource://gre/modules/FillHelpers.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  InsecurePasswordUtils: "resource://gre/modules/InsecurePasswordUtils.sys.mjs",
+  LoginFormFactory: "resource://gre/modules/LoginFormFactory.sys.mjs",
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+  LoginManagerChild: "resource://gre/modules/LoginManagerChild.sys.mjs",
+  NewPasswordModel: "resource://gre/modules/NewPasswordModel.sys.mjs",
+});
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "formFillController",
+  "@mozilla.org/satchel/form-fill-controller;1",
+  Ci.nsIFormFillController
+);
+ChromeUtils.defineLazyGetter(lazy, "log", () => {
+  return lazy.LoginHelper.createLogger("LoginAutoComplete");
+});
+ChromeUtils.defineLazyGetter(lazy, "passwordMgrBundle", () => {
+  return Services.strings.createBundle(
+    "chrome://passwordmgr/locale/passwordmgr.properties"
+  );
+});
+ChromeUtils.defineLazyGetter(lazy, "dateAndTimeFormatter", () => {
+  return new Services.intl.DateTimeFormat(undefined, {
+    dateStyle: "medium",
+  });
+});
+
+function loginSort(formHostPort, a, b) {
+  let maybeHostPortA = lazy.LoginHelper.maybeGetHostPortForURL(a.origin);
+  let maybeHostPortB = lazy.LoginHelper.maybeGetHostPortForURL(b.origin);
+  if (formHostPort == maybeHostPortA && formHostPort != maybeHostPortB) {
+    return -1;
+  }
+  if (formHostPort != maybeHostPortA && formHostPort == maybeHostPortB) {
+    return 1;
+  }
+
+  if (a.httpRealm !== b.httpRealm) {
+    // Sort HTTP auth. logins after form logins for the same origin.
+    if (b.httpRealm === null) {
+      return 1;
+    }
+    if (a.httpRealm === null) {
+      return -1;
+    }
+  }
+
+  let userA = a.username.toLowerCase();
+  let userB = b.username.toLowerCase();
+
+  if (userA < userB) {
+    return -1;
+  }
+
+  if (userA > userB) {
+    return 1;
+  }
+
+  return 0;
+}
+
+function findDuplicates(loginList) {
+  let seen = new Set();
+  let duplicates = new Set();
+  for (let login of loginList) {
+    if (seen.has(login.username)) {
+      duplicates.add(login.username);
+    }
+    seen.add(login.username);
+  }
+  return duplicates;
+}
+
+function getLocalizedString(key, ...formatArgs) {
+  if (formatArgs.length) {
+    return lazy.passwordMgrBundle.formatStringFromName(key, formatArgs);
+  }
+  return lazy.passwordMgrBundle.GetStringFromName(key);
+}
+
+class AutocompleteItem {
+  constructor(style) {
+    this.comment = "";
+    this.style = style;
+    this.value = "";
+  }
+
+  removeFromStorage() {
+    /* Do nothing by default */
+  }
+}
+
+class InsecureLoginFormAutocompleteItem extends AutocompleteItem {
+  constructor() {
+    super("insecureWarning");
+
+    this.label = getLocalizedString(
+      "insecureFieldWarningDescription2",
+      getLocalizedString("insecureFieldWarningLearnMore")
+    );
+  }
+}
+
+class LoginAutocompleteItem extends AutocompleteItem {
+  login;
+  #actor;
+
+  constructor(
+    login,
+    hasBeenTypePassword,
+    duplicateUsernames,
+    actor,
+    isOriginMatched
+  ) {
+    super("loginWithOrigin");
+    this.login = login.QueryInterface(Ci.nsILoginMetaInfo);
+    this.#actor = actor;
+
+    const isDuplicateUsername =
+      login.username && duplicateUsernames.has(login.username);
+
+    let username = login.username
+      ? login.username
+      : getLocalizedString("noUsername");
+
+    // If login is empty or duplicated we want to append a modification date to it.
+    if (!login.username || isDuplicateUsername) {
+      const time = lazy.dateAndTimeFormatter.format(
+        new Date(login.timePasswordChanged)
+      );
+      username = getLocalizedString("loginHostAge", username, time);
+    }
+
+    this.label = username;
+    this.value = hasBeenTypePassword ? login.password : login.username;
+    this.comment = JSON.stringify({
+      guid: login.guid,
+      login, // We have to keep login here to satisfy Android
+      isDuplicateUsername,
+      isOriginMatched,
+      comment:
+        isOriginMatched && login.httpRealm === null
+          ? getLocalizedString("displaySameOrigin")
+          : login.displayOrigin,
+    });
+    this.image = `page-icon:${login.origin}`;
+  }
+
+  removeFromStorage() {
+    if (this.#actor) {
+      let vanilla = lazy.LoginHelper.loginToVanillaObject(this.login);
+      this.#actor.sendAsyncMessage("PasswordManager:removeLogin", {
+        login: vanilla,
+      });
+    } else {
+      Services.logins.removeLogin(this.login);
+    }
+  }
+}
+
+class GeneratedPasswordAutocompleteItem extends AutocompleteItem {
+  constructor(generatedPassword, willAutoSaveGeneratedPassword) {
+    super("generatedPassword");
+
+    this.label = getLocalizedString("useASecurelyGeneratedPassword");
+    this.value = generatedPassword;
+    this.comment = JSON.stringify({
+      generatedPassword,
+      willAutoSaveGeneratedPassword,
+    });
+    this.image = "chrome://browser/skin/login.svg";
+  }
+}
+
+class ImportableLearnMoreAutocompleteItem extends AutocompleteItem {
+  constructor() {
+    super("importableLearnMore");
+    this.comment = JSON.stringify({
+      fillMessageName: "PasswordManager:OpenImportableLearnMore",
+    });
+  }
+}
+
+class ImportableLoginsAutocompleteItem extends AutocompleteItem {
+  #actor;
+
+  constructor(browserId, hostname, actor) {
+    super("importableLogins");
+    this.label = browserId;
+    this.comment = JSON.stringify({
+      hostname,
+      fillMessageName: "PasswordManager:HandleImportable",
+      fillMessageData: {
+        browserId,
+      },
+    });
+    this.#actor = actor;
+
+    // This is sent for every item (re)shown, but the parent will debounce to
+    // reduce the count by 1 total.
+    this.#actor.sendAsyncMessage(
+      "PasswordManager:decreaseSuggestImportCount",
+      1
+    );
+  }
+
+  removeFromStorage() {
+    this.#actor.sendAsyncMessage(
+      "PasswordManager:decreaseSuggestImportCount",
+      100
+    );
+  }
+}
+
+class LoginsFooterAutocompleteItem extends AutocompleteItem {
+  constructor(formHostname, telemetryEventData) {
+    super("loginsFooter");
+
+    this.label = getLocalizedString("managePasswords.label");
+
+    // The comment field of `loginsFooter` results have many additional pieces of
+    // information for telemetry purposes. After bug 1555209, this information
+    // can be passed to the parent process outside of nsIAutoCompleteResult APIs
+    // so we won't need this hack.
+    this.comment = JSON.stringify({
+      telemetryEventData,
+      formHostname,
+      fillMessageName: "PasswordManager:OpenPreferences",
+      fillMessageData: {
+        entryPoint: "autocomplete",
+      },
+    });
+  }
+}
+
+// nsIAutoCompleteResult implementation
+export class LoginAutoCompleteResult {
+  #rows = [];
+
+  constructor(
+    aSearchString,
+    matchingLogins,
+    autocompleteItems,
+    formOrigin,
+    {
+      generatedPassword,
+      willAutoSaveGeneratedPassword,
+      importable,
+      isSecure,
+      actor,
+      hasBeenTypePassword,
+      hostname,
+      telemetryEventData,
+    }
+  ) {
+    let hidingFooterOnPWFieldAutoOpened = false;
+    const importableBrowsers =
+      importable?.state === "import" && importable?.browsers;
+
+    function isFooterEnabled() {
+      // We need to check LoginHelper.enabled here since the insecure warning should
+      // appear even if pwmgr is disabled but the footer should never appear in that case.
+      if (
+        !lazy.LoginHelper.showAutoCompleteFooter ||
+        !lazy.LoginHelper.enabled
+      ) {
+        return false;
+      }
+
+      // Don't show the footer on non-empty password fields as it's not providing
+      // value and only adding noise since a password was already filled.
+      if (hasBeenTypePassword && aSearchString && !generatedPassword) {
+        lazy.log.debug("Hiding footer: non-empty password field");
+        return false;
+      }
+
+      if (
+        !autocompleteItems?.length &&
+        !importableBrowsers &&
+        !matchingLogins.length &&
+        !generatedPassword &&
+        hasBeenTypePassword &&
+        lazy.formFillController.passwordPopupAutomaticallyOpened
+      ) {
+        hidingFooterOnPWFieldAutoOpened = true;
+        lazy.log.debug(
+          "Hiding footer: no logins and the popup was opened upon focus of the pw. field"
+        );
+        return false;
+      }
+
+      return true;
+    }
+
+    this.searchString = aSearchString;
+
+    // Insecure field warning comes first.
+    if (!isSecure) {
+      this.#rows.push(new InsecureLoginFormAutocompleteItem());
+    }
+
+    // Saved login items
+    let formHostPort = lazy.LoginHelper.maybeGetHostPortForURL(formOrigin);
+    let logins = matchingLogins.sort(loginSort.bind(null, formHostPort));
+    let duplicateUsernames = findDuplicates(matchingLogins);
+
+    for (let login of logins) {
+      let item = new LoginAutocompleteItem(
+        login,
+        hasBeenTypePassword,
+        duplicateUsernames,
+        actor,
+        lazy.LoginHelper.isOriginMatching(login.origin, formOrigin, {
+          schemeUpgrades: lazy.LoginHelper.schemeUpgrades,
+        })
+      );
+      this.#rows.push(item);
+    }
+
+    // The footer comes last if it's enabled
+    if (isFooterEnabled()) {
+      if (autocompleteItems) {
+        this.#rows.push(
+          ...autocompleteItems.map(
+            item =>
+              new GenericAutocompleteItem(
+                item.image,
+                item.title,
+                item.subtitle,
+                item.fillMessageName,
+                item.fillMessageData
+              )
+          )
+        );
+      }
+
+      if (generatedPassword) {
+        this.#rows.push(
+          new GeneratedPasswordAutocompleteItem(
+            generatedPassword,
+            willAutoSaveGeneratedPassword
+          )
+        );
+      }
+
+      // Suggest importing logins if there are none found.
+      if (!logins.length && importableBrowsers) {
+        this.#rows.push(
+          ...importableBrowsers.map(
+            browserId =>
+              new ImportableLoginsAutocompleteItem(browserId, hostname, actor)
+          )
+        );
+        this.#rows.push(new ImportableLearnMoreAutocompleteItem());
+      }
+
+      // If we have anything in autocomplete, then add "Manage Passwords"
+      this.#rows.push(
+        new LoginsFooterAutocompleteItem(hostname, telemetryEventData)
+      );
+    }
+
+    // Determine the result code and default index.
+    if (this.matchCount > 0) {
+      this.searchResult = Ci.nsIAutoCompleteResult.RESULT_SUCCESS;
+      this.defaultIndex = 0;
+    } else if (hidingFooterOnPWFieldAutoOpened) {
+      // We use a failure result so that the empty results aren't re-used for when
+      // the user tries to manually open the popup (we want the footer in that case).
+      this.searchResult = Ci.nsIAutoCompleteResult.RESULT_FAILURE;
+      this.defaultIndex = -1;
+    }
+  }
+
+  QueryInterface = ChromeUtils.generateQI([
+    "nsIAutoCompleteResult",
+    "nsISupportsWeakReference",
+  ]);
+
+  /**
+   * Accessed via .wrappedJSObject
+   * @private
+   */
+  get logins() {
+    return this.#rows
+      .filter(item => item instanceof LoginAutocompleteItem)
+      .map(item => item.login);
+  }
+
+  // Allow autoCompleteSearch to get at the JS object so it can
+  // modify some readonly properties for internal use.
+  get wrappedJSObject() {
+    return this;
+  }
+
+  // Interfaces from idl...
+  searchString = null;
+  searchResult = Ci.nsIAutoCompleteResult.RESULT_NOMATCH;
+  defaultIndex = -1;
+  errorDescription = "";
+
+  get matchCount() {
+    return this.#rows.length;
+  }
+
+  #throwOnBadIndex(index) {
+    if (index < 0 || index >= this.matchCount) {
+      throw new Error("Index out of range.");
+    }
+  }
+
+  getValueAt(index) {
+    this.#throwOnBadIndex(index);
+    return this.#rows[index].value;
+  }
+
+  getLabelAt(index) {
+    this.#throwOnBadIndex(index);
+    return this.#rows[index].label;
+  }
+
+  getCommentAt(index) {
+    this.#throwOnBadIndex(index);
+    return this.#rows[index].comment;
+  }
+
+  getStyleAt(index) {
+    this.#throwOnBadIndex(index);
+    return this.#rows[index].style;
+  }
+
+  getImageAt(index) {
+    this.#throwOnBadIndex(index);
+    return this.#rows[index].image ?? "";
+  }
+
+  getFinalCompleteValueAt(index) {
+    return this.getValueAt(index);
+  }
+
+  isRemovableAt(index) {
+    this.#throwOnBadIndex(index);
+    return true;
+  }
+
+  removeValueAt(index) {
+    this.#throwOnBadIndex(index);
+
+    let [removedItem] = this.#rows.splice(index, 1);
+
+    if (this.defaultIndex > this.#rows.length) {
+      this.defaultIndex--;
+    }
+
+    removedItem.removeFromStorage();
+  }
+}
+
+export class LoginAutoComplete {
+  // HTMLInputElement to number, the element's new-password heuristic confidence score
+  #cachedNewPasswordScore = new WeakMap();
+  #autoCompleteLookupPromise = null;
+  classID = Components.ID("{2bdac17c-53f1-4896-a521-682ccdeef3a8}");
+  QueryInterface = ChromeUtils.generateQI(["nsILoginAutoCompleteSearch"]);
+
+  /**
+   * Yuck. This is called directly by satchel:
+   * nsFormFillController::StartSearch()
+   * [toolkit/components/satchel/nsFormFillController.cpp]
+   *
+   * We really ought to have a simple way for code to register an
+   * auto-complete provider, and not have satchel calling pwmgr directly.
+   *
+   * @param {string} aSearchString The value typed in the field.
+   * @param {nsIAutoCompleteResult} aPreviousResult
+   * @param {HTMLInputElement} aElement
+   * @param {nsIFormAutoCompleteObserver} aCallback
+   */
+  startSearch(aSearchString, aPreviousResult, aElement, aCallback) {
+    let { isNullPrincipal } = aElement.nodePrincipal;
+    if (
+      aElement.nodePrincipal.schemeIs("about") ||
+      aElement.nodePrincipal.isSystemPrincipal
+    ) {
+      // Don't show autocomplete results for about: pages.
+      // XXX: Don't we need to call the callback here?
+      return;
+    }
+
+    let searchStartTimeMS = Services.telemetry.msSystemNow();
+
+    // Show the insecure login warning in the passwords field on null principal documents.
+    // Avoid loading InsecurePasswordUtils.jsm in a sandboxed document (e.g. an ad. frame) if we
+    // already know it has a null principal and will therefore get the insecure autocomplete
+    // treatment.
+    // InsecurePasswordUtils doesn't handle the null principal case as not secure because we don't
+    // want the same treatment:
+    // * The web console warnings will be confusing (as they're primarily about http:) and not very
+    //   useful if the developer intentionally sandboxed the document.
+    // * The site identity insecure field warning would require LoginManagerChild being loaded and
+    //   listening to some of the DOM events we're ignoring in null principal documents. For memory
+    //   reasons it's better to not load LMC at all for these sandboxed frames. Also, if the top-
+    //   document is sandboxing a document, it probably doesn't want that sandboxed document to be
+    //   able to affect the identity icon in the address bar by adding a password field.
+    let form = lazy.LoginFormFactory.createFromField(aElement);
+    let isSecure =
+      !isNullPrincipal && lazy.InsecurePasswordUtils.isFormSecure(form);
+    let { hasBeenTypePassword } = aElement;
+    let hostname = aElement.ownerDocument.documentURIObject.host;
+    let formOrigin = lazy.LoginHelper.getLoginOrigin(
+      aElement.ownerDocument.documentURI
+    );
+    let loginManagerActor = lazy.LoginManagerChild.forWindow(
+      aElement.ownerGlobal
+    );
+    let completeSearch = async autoCompleteLookupPromise => {
+      // Assign to the member synchronously before awaiting the Promise.
+      this.#autoCompleteLookupPromise = autoCompleteLookupPromise;
+
+      let {
+        generatedPassword,
+        importable,
+        logins,
+        autocompleteItems,
+        willAutoSaveGeneratedPassword,
+      } = await autoCompleteLookupPromise;
+
+      // If the search was canceled before we got our
+      // results, don't bother reporting them.
+      // N.B. This check must occur after the `await` above for it to be
+      // effective.
+      if (this.#autoCompleteLookupPromise !== autoCompleteLookupPromise) {
+        lazy.log.debug("Ignoring result from previous search.");
+        return;
+      }
+
+      let telemetryEventData = {
+        acFieldName: aElement.getAutocompleteInfo().fieldName,
+        hadPrevious: !!aPreviousResult,
+        typeWasPassword: aElement.hasBeenTypePassword,
+        fieldType: aElement.type,
+        searchStartTimeMS,
+        stringLength: aSearchString.length,
+      };
+
+      this.#autoCompleteLookupPromise = null;
+      let results = new LoginAutoCompleteResult(
+        aSearchString,
+        logins,
+        autocompleteItems,
+        formOrigin,
+        {
+          generatedPassword,
+          willAutoSaveGeneratedPassword,
+          importable,
+          actor: loginManagerActor,
+          isSecure,
+          hasBeenTypePassword,
+          hostname,
+          telemetryEventData,
+        }
+      );
+      aCallback.onSearchCompletion(results);
+    };
+
+    if (isNullPrincipal) {
+      // Don't search login storage when the field has a null principal as we don't want to fill
+      // logins for the `location` in this case.
+      completeSearch(Promise.resolve({ logins: [] }));
+      return;
+    }
+
+    if (
+      hasBeenTypePassword &&
+      aSearchString &&
+      !loginManagerActor.isPasswordGenerationForcedOn(aElement)
+    ) {
+      // Return empty result on password fields with password already filled,
+      // unless password generation was forced.
+      completeSearch(Promise.resolve({ logins: [] }));
+      return;
+    }
+
+    if (!lazy.LoginHelper.enabled) {
+      completeSearch(Promise.resolve({ logins: [] }));
+      return;
+    }
+
+    let previousResult;
+    if (aPreviousResult) {
+      previousResult = {
+        searchString: aPreviousResult.searchString,
+        logins: lazy.LoginHelper.loginsToVanillaObjects(
+          aPreviousResult.wrappedJSObject.logins
+        ),
+      };
+    } else {
+      previousResult = null;
+    }
+
+    let acLookupPromise = this.#requestAutoCompleteResultsFromParent({
+      searchString: aSearchString,
+      previousResult,
+      inputElement: aElement,
+      form,
+      hasBeenTypePassword,
+    });
+    completeSearch(acLookupPromise).catch(lazy.log.error.bind(lazy.log));
+  }
+
+  stopSearch() {
+    this.#autoCompleteLookupPromise = null;
+  }
+
+  async #requestAutoCompleteResultsFromParent({
+    searchString,
+    previousResult,
+    inputElement,
+    form,
+    hasBeenTypePassword,
+  }) {
+    let actionOrigin = lazy.LoginHelper.getFormActionOrigin(form);
+    let autocompleteInfo = inputElement.getAutocompleteInfo();
+
+    let loginManagerActor = lazy.LoginManagerChild.forWindow(
+      inputElement.ownerGlobal
+    );
+    let forcePasswordGeneration = false;
+    let isProbablyANewPasswordField = false;
+    if (hasBeenTypePassword) {
+      forcePasswordGeneration =
+        loginManagerActor.isPasswordGenerationForcedOn(inputElement);
+      // Run the Fathom model only if the password field does not have the
+      // autocomplete="new-password" attribute.
+      isProbablyANewPasswordField =
+        autocompleteInfo.fieldName == "new-password" ||
+        this.isProbablyANewPasswordField(inputElement);
+    }
+    const scenario = loginManagerActor.getScenario(inputElement);
+
+    if (lazy.LoginHelper.showAutoCompleteFooter) {
+      gAutoCompleteListener.init();
+    }
+
+    lazy.log.debug("LoginAutoComplete search:", {
+      forcePasswordGeneration,
+      hasBeenTypePassword,
+      isProbablyANewPasswordField,
+      searchStringLength: searchString.length,
+    });
+
+    const result = await loginManagerActor.sendQuery(
+      "PasswordManager:autoCompleteLogins",
+      {
+        actionOrigin,
+        searchString,
+        previousResult,
+        forcePasswordGeneration,
+        hasBeenTypePassword,
+        isProbablyANewPasswordField,
+        scenarioName: scenario?.constructor.name,
+        inputMaxLength: inputElement.maxLength,
+        isWebAuthn: this.#isWebAuthnCredentials(autocompleteInfo),
+      }
+    );
+
+    return {
+      generatedPassword: result.generatedPassword,
+      importable: result.importable,
+      autocompleteItems: result.autocompleteItems,
+      logins: lazy.LoginHelper.vanillaObjectsToLogins(result.logins),
+      willAutoSaveGeneratedPassword: result.willAutoSaveGeneratedPassword,
+    };
+  }
+
+  isProbablyANewPasswordField(inputElement) {
+    const threshold = lazy.LoginHelper.generationConfidenceThreshold;
+    if (threshold == -1) {
+      // Fathom is disabled
+      return false;
+    }
+
+    let score = this.#cachedNewPasswordScore.get(inputElement);
+    if (score) {
+      return score >= threshold;
+    }
+
+    const { rules, type } = lazy.NewPasswordModel;
+    const results = rules.against(inputElement);
+    score = results.get(inputElement).scoreFor(type);
+    this.#cachedNewPasswordScore.set(inputElement, score);
+    return score >= threshold;
+  }
+
+  /**
+   * @param {string} autocompleteInfo
+   * @returns whether the non-autofill credential type (https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#non-autofill-credential-type)
+   * of the input field is "webauthn"
+   */
+  #isWebAuthnCredentials(autocompleteInfo) {
+    return autocompleteInfo.credentialType == "webauthn";
+  }
+}
+
+let gAutoCompleteListener = {
+  added: false,
+  fillRequestId: 0,
+
+  init() {
+    if (!this.added) {
+      Services.obs.addObserver(this, "autocomplete-will-enter-text");
+      this.added = true;
+    }
+  },
+
+  async observe(subject, topic, data) {
+    switch (topic) {
+      case "autocomplete-will-enter-text": {
+        await this.sendFillRequestToLoginManagerParent(subject, data);
+        break;
+      }
+    }
+  },
+
+  async sendFillRequestToLoginManagerParent(input, comment) {
+    if (!comment) {
+      return;
+    }
+
+    if (input != lazy.formFillController.controller.input) {
+      return;
+    }
+
+    const { fillMessageName, fillMessageData } = JSON.parse(comment ?? "{}");
+    if (!fillMessageName) {
+      return;
+    }
+
+    this.fillRequestId++;
+    const fillRequestId = this.fillRequestId;
+    const child = lazy.LoginManagerChild.forWindow(
+      input.focusedInput.ownerGlobal
+    );
+    const value = await child.sendQuery(fillMessageName, fillMessageData ?? {});
+
+    // skip fill if another fill operation started during await
+    if (fillRequestId != this.fillRequestId) {
+      return;
+    }
+
+    if (typeof value !== "string") {
+      return;
+    }
+
+    // If LoginManagerParent returned a string to fill, we must do it here because
+    // nsAutoCompleteController.cpp already finished it's work before we finished await.
+    input.textValue = value;
+    input.selectTextRange(value.length, value.length);
+  },
+};
diff --git a/toolkit/components/passwordmgr/LoginCSVImport.sys.mjs b/toolkit/components/passwordmgr/LoginCSVImport.sys.mjs
new file mode 100644
index 0000000000..2e9db07014
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginCSVImport.sys.mjs
@@ -0,0 +1,199 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Provides a class to import login-related data CSV files.
+ */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  CSV: "resource://gre/modules/CSV.sys.mjs",
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+});
+
+/**
+ * All the CSV column names will be converted to lower case before lookup
+ * so they must be specified here in lower case.
+ */
+const FIELD_TO_CSV_COLUMNS = {
+  origin: ["url", "login_uri"],
+  username: ["username", "login_username"],
+  password: ["password", "login_password"],
+  httpRealm: ["httprealm"],
+  formActionOrigin: ["formactionorigin"],
+  guid: ["guid"],
+  timeCreated: ["timecreated"],
+  timeLastUsed: ["timelastused"],
+  timePasswordChanged: ["timepasswordchanged"],
+};
+
+export const ImportFailedErrorType = Object.freeze({
+  CONFLICTING_VALUES_ERROR: "CONFLICTING_VALUES_ERROR",
+  FILE_FORMAT_ERROR: "FILE_FORMAT_ERROR",
+  FILE_PERMISSIONS_ERROR: "FILE_PERMISSIONS_ERROR",
+  UNABLE_TO_READ_ERROR: "UNABLE_TO_READ_ERROR",
+});
+
+export class ImportFailedException extends Error {
+  constructor(errorType, message) {
+    super(message != null ? message : errorType);
+    this.errorType = errorType;
+  }
+}
+
+/**
+ * Provides an object that has a method to import login-related data CSV files
+ */
+export class LoginCSVImport {
+  /**
+   * Returns a map that has the csv column name as key and the value the field name.
+   *
+   * @returns {Map} A map that has the csv column name as key and the value the field name.
+   */
+  static _getCSVColumnToFieldMap() {
+    let csvColumnToField = new Map();
+    for (let [field, columns] of Object.entries(FIELD_TO_CSV_COLUMNS)) {
+      for (let column of columns) {
+        csvColumnToField.set(column.toLowerCase(), field);
+      }
+    }
+    return csvColumnToField;
+  }
+
+  /**
+   * Builds a vanilla JS object containing all the login fields from a row of CSV cells.
+   *
+   * @param {object} csvObject
+   *        An object created from a csv row. The keys are the csv column names, the values are the cells.
+   * @param {Map} csvColumnToFieldMap
+   *        A map where the keys are the csv properties and the values are the object keys.
+   * @returns {object} Representing login object with only properties, not functions.
+   */
+  static _getVanillaLoginFromCSVObject(csvObject, csvColumnToFieldMap) {
+    let vanillaLogin = Object.create(null);
+    for (let columnName of Object.keys(csvObject)) {
+      let fieldName = csvColumnToFieldMap.get(columnName.toLowerCase());
+      if (!fieldName) {
+        continue;
+      }
+
+      if (
+        typeof vanillaLogin[fieldName] != "undefined" &&
+        vanillaLogin[fieldName] !== csvObject[columnName]
+      ) {
+        // Differing column values map to one property.
+        // e.g. if two headings map to `origin` we won't know which to use.
+        return {};
+      }
+
+      vanillaLogin[fieldName] = csvObject[columnName];
+    }
+
+    // Since `null` can't be represented in a CSV file and the httpRealm header
+    // cannot be an empty string, assume that an empty httpRealm means this is
+    // a form login and therefore null-out httpRealm.
+    if (vanillaLogin.httpRealm === "") {
+      vanillaLogin.httpRealm = null;
+    }
+
+    return vanillaLogin;
+  }
+  static _recordHistogramTelemetry(histogram, report) {
+    for (let reportRow of report) {
+      let { result } = reportRow;
+      if (result.includes("error")) {
+        histogram.add("error");
+      } else {
+        histogram.add(result);
+      }
+    }
+  }
+  /**
+   * Imports logins from a CSV file (comma-separated values file).
+   * Existing logins may be updated in the process.
+   *
+   * @param {string} filePath
+   * @returns {Object[]} An array of rows where each is mapped to a row in the CSV and it's import information.
+   */
+  static async importFromCSV(filePath) {
+    let csvColumnToFieldMap = LoginCSVImport._getCSVColumnToFieldMap();
+    let csvFieldToColumnMap = new Map();
+
+    let csvString;
+    try {
+      csvString = await IOUtils.readUTF8(filePath, { encoding: "utf-8" });
+    } catch (ex) {
+      console.error(ex);
+      throw new ImportFailedException(
+        ImportFailedErrorType.FILE_PERMISSIONS_ERROR
+      );
+    }
+    let headerLine;
+    let parsedLines;
+    try {
+      let delimiter = filePath.toUpperCase().endsWith(".CSV") ? "," : "\t";
+      [headerLine, parsedLines] = lazy.CSV.parse(csvString, delimiter);
+    } catch {
+      throw new ImportFailedException(ImportFailedErrorType.FILE_FORMAT_ERROR);
+    }
+    if (parsedLines && headerLine) {
+      for (const columnName of headerLine) {
+        const fieldName = csvColumnToFieldMap.get(
+          columnName.toLocaleLowerCase()
+        );
+        if (fieldName) {
+          if (!csvFieldToColumnMap.has(fieldName)) {
+            csvFieldToColumnMap.set(fieldName, columnName);
+          } else {
+            throw new ImportFailedException(
+              ImportFailedErrorType.CONFLICTING_VALUES_ERROR
+            );
+          }
+        }
+      }
+    }
+    if (csvFieldToColumnMap.size === 0) {
+      throw new ImportFailedException(ImportFailedErrorType.FILE_FORMAT_ERROR);
+    }
+    if (
+      parsedLines[0] &&
+      (!csvFieldToColumnMap.has("origin") ||
+        !csvFieldToColumnMap.has("username") ||
+        !csvFieldToColumnMap.has("password"))
+    ) {
+      // The username *value* can be empty but we require a username column to
+      // ensure that we don't import logins without their usernames due to the
+      // username column not being recognized.
+      throw new ImportFailedException(ImportFailedErrorType.FILE_FORMAT_ERROR);
+    }
+
+    let loginsToImport = parsedLines.map(csvObject => {
+      return LoginCSVImport._getVanillaLoginFromCSVObject(
+        csvObject,
+        csvColumnToFieldMap
+      );
+    });
+
+    let report = await lazy.LoginHelper.maybeImportLogins(loginsToImport);
+
+    for (const reportRow of report) {
+      if (reportRow.result === "error_missing_field") {
+        reportRow.field_name = csvFieldToColumnMap.get(reportRow.field_name);
+      }
+    }
+
+    // Record quantity and duration telemetry.
+    try {
+      let histogram = Services.telemetry.getHistogramById(
+        "PWMGR_IMPORT_LOGINS_FROM_FILE_CATEGORICAL"
+      );
+      this._recordHistogramTelemetry(histogram, report);
+    } catch (ex) {
+      console.error(ex);
+    }
+    LoginCSVImport.lastImportReport = report;
+    return report;
+  }
+}
diff --git a/toolkit/components/passwordmgr/LoginExport.sys.mjs b/toolkit/components/passwordmgr/LoginExport.sys.mjs
new file mode 100644
index 0000000000..20d6a80952
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginExport.sys.mjs
@@ -0,0 +1,76 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Module to support exporting logins to a .csv file.
+ */
+
+export class LoginExport {
+  /**
+   * Builds an array of strings representing a row in a CSV.
+   *
+   * @param {nsILoginInfo} login
+   *        The object that will be converted into a csv row.
+   * @param {string[]} columns
+   *        The CSV columns, used to find the properties from the login object.
+   * @returns {string[]} Representing a row.
+   */
+  static _buildCSVRow(login, columns) {
+    let row = [];
+    for (let columnName of columns) {
+      let columnValue = login[columnName];
+      if (typeof columnValue == "string") {
+        columnValue = columnValue.split('"').join('""');
+      }
+      if (columnValue !== null && columnValue != undefined) {
+        row.push(`"${columnValue}"`);
+      } else {
+        row.push("");
+      }
+    }
+    return row;
+  }
+
+  /**
+   * Given a path it saves all the logins as a CSV file.
+   *
+   * @param {string} path
+   *        The file path to save the login to.
+   * @param {nsILoginInfo[]} [logins = null]
+   *        An optional list of logins.
+   */
+  static async exportAsCSV(path, logins = null) {
+    if (!logins) {
+      logins = await Services.logins.getAllLogins();
+    }
+    let columns = [
+      "origin",
+      "username",
+      "password",
+      "httpRealm",
+      "formActionOrigin",
+      "guid",
+      "timeCreated",
+      "timeLastUsed",
+      "timePasswordChanged",
+    ];
+    let csvHeader = columns.map(name => {
+      if (name == "origin") {
+        return '"url"';
+      }
+      return `"${name}"`;
+    });
+
+    let rows = [];
+    rows.push(csvHeader);
+    for (let login of logins) {
+      rows.push(LoginExport._buildCSVRow(login, columns));
+    }
+    // https://tools.ietf.org/html/rfc7111 suggests always using CRLF.
+    const csvAsString = rows.map(e => e.join(",")).join("\r\n");
+    await IOUtils.writeUTF8(path, csvAsString, {
+      tmpPath: path + ".tmp",
+    });
+  }
+}
diff --git a/toolkit/components/passwordmgr/LoginFormFactory.sys.mjs b/toolkit/components/passwordmgr/LoginFormFactory.sys.mjs
new file mode 100644
index 0000000000..32dc3e3cfa
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginFormFactory.sys.mjs
@@ -0,0 +1,148 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * A factory to generate LoginForm objects that represent a set of login fields
+ * which aren't necessarily marked up with a <form> element.
+ */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  FormLikeFactory: "resource://gre/modules/FormLikeFactory.sys.mjs",
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+});
+
+ChromeUtils.defineLazyGetter(lazy, "log", () => {
+  return lazy.LoginHelper.createLogger("LoginFormFactory");
+});
+
+export const LoginFormFactory = {
+  /**
+   * WeakMap of the root element of a LoginForm to the LoginForm representing its fields.
+   *
+   * This is used to be able to lookup an existing LoginForm for a given root element since multiple
+   * calls to LoginFormFactory.createFrom* won't give the exact same object. When batching fills we don't always
+   * want to use the most recent list of elements for a LoginForm since we may end up doing multiple
+   * fills for the same set of elements when a field gets added between arming and running the
+   * DeferredTask.
+   *
+   * @type {WeakMap}
+   */
+  _loginFormsByRootElement: new WeakMap(),
+
+  /**
+   * Maps all DOM content documents in this content process, including those in
+   * frames, to a WeakSet of LoginForm.rootElement for the document.
+   */
+  _loginFormRootElementsByDocument: new WeakMap(),
+
+  /**
+   * Create a LoginForm object from a <form>.
+   *
+   * @param {HTMLFormElement} aForm
+   * @return {LoginForm}
+   * @throws Error if aForm isn't an HTMLFormElement
+   */
+  createFromForm(aForm) {
+    let formLike = lazy.FormLikeFactory.createFromForm(aForm);
+    formLike.action = lazy.LoginHelper.getFormActionOrigin(aForm);
+
+    let rootElementsSet = this.getRootElementsWeakSetForDocument(
+      formLike.ownerDocument
+    );
+    rootElementsSet.add(formLike.rootElement);
+    lazy.log.debug(
+      "adding",
+      formLike.rootElement,
+      "to root elements for",
+      formLike.ownerDocument
+    );
+
+    this._loginFormsByRootElement.set(formLike.rootElement, formLike);
+    return formLike;
+  },
+
+  /**
+   * Create a LoginForm object from a password or username field.
+   *
+   * If the field is in a <form>, construct the LoginForm from the form.
+   * Otherwise, create a LoginForm with a rootElement (wrapper) according to
+   * heuristics. Currently all <input> not in a <form> are one LoginForm but this
+   * shouldn't be relied upon as the heuristics may change to detect multiple
+   * "forms" (e.g. registration and login) on one page with a <form>.
+   *
+   * Note that two LoginForms created from the same field won't return the same LoginForm object.
+   * Use the `rootElement` property on the LoginForm as a key instead.
+   *
+   * @param {HTMLInputElement} aField - a password or username field in a document
+   * @return {LoginForm}
+   * @throws Error if aField isn't a password or username field in a document
+   */
+  createFromField(aField) {
+    if (
+      !HTMLInputElement.isInstance(aField) ||
+      (!aField.hasBeenTypePassword &&
+        !lazy.LoginHelper.isUsernameFieldType(aField)) ||
+      !aField.ownerDocument
+    ) {
+      throw new Error(
+        "createFromField requires a password or username field in a document"
+      );
+    }
+
+    let form =
+      aField.form ||
+      lazy.FormLikeFactory.closestFormIgnoringShadowRoots(aField);
+    if (form) {
+      return this.createFromForm(form);
+    } else if (aField.hasAttribute("form")) {
+      lazy.log.debug(
+        "createFromField: field has form attribute but no form: ",
+        aField.getAttribute("form")
+      );
+    }
+
+    let formLike = lazy.FormLikeFactory.createFromField(aField);
+    formLike.action = lazy.LoginHelper.getLoginOrigin(
+      aField.ownerDocument.baseURI
+    );
+    lazy.log.debug(
+      "Created non-form LoginForm for rootElement:",
+      aField.ownerDocument.documentElement
+    );
+
+    let rootElementsSet = this.getRootElementsWeakSetForDocument(
+      formLike.ownerDocument
+    );
+    rootElementsSet.add(formLike.rootElement);
+    lazy.log.debug(
+      "adding",
+      formLike.rootElement,
+      "to root elements for",
+      formLike.ownerDocument
+    );
+
+    this._loginFormsByRootElement.set(formLike.rootElement, formLike);
+
+    return formLike;
+  },
+
+  getRootElementsWeakSetForDocument(aDocument) {
+    let rootElementsSet = this._loginFormRootElementsByDocument.get(aDocument);
+    if (!rootElementsSet) {
+      rootElementsSet = new WeakSet();
+      this._loginFormRootElementsByDocument.set(aDocument, rootElementsSet);
+    }
+    return rootElementsSet;
+  },
+
+  getForRootElement(aRootElement) {
+    return this._loginFormsByRootElement.get(aRootElement);
+  },
+
+  setForRootElement(aRootElement, aLoginForm) {
+    return this._loginFormsByRootElement.set(aRootElement, aLoginForm);
+  },
+};
diff --git a/toolkit/components/passwordmgr/LoginHelper.sys.mjs b/toolkit/components/passwordmgr/LoginHelper.sys.mjs
new file mode 100644
index 0000000000..a63654c8f2
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginHelper.sys.mjs
@@ -0,0 +1,1883 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Contains functions shared by different Login Manager components.
+ *
+ * This JavaScript module exists in order to share code between the different
+ * XPCOM components that constitute the Login Manager, including implementations
+ * of nsILoginManager and nsILoginManagerStorage.
+ */
+
+import { Logic } from "resource://gre/modules/LoginManager.shared.mjs";
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+
+const lazy = {};
+ChromeUtils.defineESModuleGetters(lazy, {
+  OSKeyStore: "resource://gre/modules/OSKeyStore.sys.mjs",
+});
+
+export class ParentAutocompleteOption {
+  image;
+  title;
+  subtitle;
+  fillMessageName;
+  fillMessageData;
+
+  constructor(image, title, subtitle, fillMessageName, fillMessageData) {
+    this.image = image;
+    this.title = title;
+    this.subtitle = subtitle;
+    this.fillMessageName = fillMessageName;
+    this.fillMessageData = fillMessageData;
+  }
+}
+
+/**
+ * A helper class to deal with CSV import rows.
+ */
+class ImportRowProcessor {
+  uniqueLoginIdentifiers = new Set();
+  originToRows = new Map();
+  summary = [];
+  mandatoryFields = ["origin", "password"];
+
+  /**
+   * Validates if the login data contains a GUID that was already found in a previous row in the current import.
+   * If this is the case, the summary will be updated with an error.
+   * @param {object} loginData
+   *        An vanilla object for the login without any methods.
+   * @returns {boolean} True if there is an error, false otherwise.
+   */
+  checkNonUniqueGuidError(loginData) {
+    if (loginData.guid) {
+      if (this.uniqueLoginIdentifiers.has(loginData.guid)) {
+        this.addLoginToSummary({ ...loginData }, "error");
+        return true;
+      }
+      this.uniqueLoginIdentifiers.add(loginData.guid);
+    }
+    return false;
+  }
+
+  /**
+   * Validates if the login data contains invalid fields that are mandatory like origin and password.
+   * If this is the case, the summary will be updated with an error.
+   * @param {object} loginData
+   *        An vanilla object for the login without any methods.
+   * @returns {boolean} True if there is an error, false otherwise.
+   */
+  checkMissingMandatoryFieldsError(loginData) {
+    loginData.origin = LoginHelper.getLoginOrigin(loginData.origin);
+    for (let mandatoryField of this.mandatoryFields) {
+      if (!loginData[mandatoryField]) {
+        const missingFieldRow = this.addLoginToSummary(
+          { ...loginData },
+          "error_missing_field"
+        );
+        missingFieldRow.field_name = mandatoryField;
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Validates if there is already an existing entry with similar values.
+   * If there are similar values but not identical, a new "modified" entry will be added to the summary.
+   * If there are identical values, a new "no_change" entry will be added to the summary
+   * If either of these is the case, it will return true.
+   * @param {object} loginData
+   *        An vanilla object for the login without any methods.
+   * @returns {boolean} True if the entry is similar or identical to another previously processed entry, false otherwise.
+   */
+  async checkExistingEntry(loginData) {
+    if (loginData.guid) {
+      // First check for `guid` matches if it's set.
+      // `guid` matches will allow every kind of update, including reverting
+      // to older passwords which can be useful if the user wants to recover
+      // an old password.
+      let existingLogins = await Services.logins.searchLoginsAsync({
+        guid: loginData.guid,
+        origin: loginData.origin, // Ignored outside of GV.
+      });
+
+      if (existingLogins.length) {
+        lazy.log.debug("maybeImportLogins: Found existing login with GUID.");
+        // There should only be one `guid` match.
+        let existingLogin = existingLogins[0].QueryInterface(
+          Ci.nsILoginMetaInfo
+        );
+
+        if (
+          loginData.username !== existingLogin.username ||
+          loginData.password !== existingLogin.password ||
+          loginData.httpRealm !== existingLogin.httpRealm ||
+          loginData.formActionOrigin !== existingLogin.formActionOrigin ||
+          `${loginData.timeCreated}` !== `${existingLogin.timeCreated}` ||
+          `${loginData.timePasswordChanged}` !==
+            `${existingLogin.timePasswordChanged}`
+        ) {
+          // Use a property bag rather than an nsILoginInfo so we don't clobber
+          // properties that the import source doesn't provide.
+          let propBag = LoginHelper.newPropertyBag(loginData);
+          this.addLoginToSummary({ ...existingLogin }, "modified", propBag);
+          return true;
+        }
+        this.addLoginToSummary({ ...existingLogin }, "no_change");
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Validates if there is a conflict with previous rows based on the origin.
+   * We need to check the logins that we've already decided to add, to see if this is a duplicate.
+   * If this is the case, we mark this one as "no_change" in the summary and return true.
+   * @param {object} login
+   *        A login object.
+   * @returns {boolean} True if the entry is similar or identical to another previously processed entry, false otherwise.
+   */
+  checkConflictingOriginWithPreviousRows(login) {
+    let rowsPerOrigin = this.originToRows.get(login.origin);
+    if (rowsPerOrigin) {
+      if (
+        rowsPerOrigin.some(r =>
+          login.matches(r.login, false /* ignorePassword */)
+        )
+      ) {
+        this.addLoginToSummary(login, "no_change");
+        return true;
+      }
+      for (let row of rowsPerOrigin) {
+        let newLogin = row.login;
+        if (login.username == newLogin.username) {
+          this.addLoginToSummary(login, "no_change");
+          return true;
+        }
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Validates if there is a conflict with existing logins based on the origin.
+   * If this is the case and there are some changes, we mark it as "modified" in the summary.
+   * If it matches an existing login without any extra modifications, we mark it as "no_change".
+   * For both cases we return true.
+   * @param {object} login
+   *        A login object.
+   * @returns {boolean} True if the entry is similar or identical to another previously processed entry, false otherwise.
+   */
+  async checkConflictingWithExistingLogins(login) {
+    // While here we're passing formActionOrigin and httpRealm, they could be empty/null and get
+    // ignored in that case, leading to multiple logins for the same username.
+    let existingLogins = await Services.logins.searchLoginsAsync({
+      origin: login.origin,
+      formActionOrigin: login.formActionOrigin,
+      httpRealm: login.httpRealm,
+    });
+
+    // Check for an existing login that matches *including* the password.
+    // If such a login exists, we do not need to add a new login.
+    if (
+      existingLogins.some(l => login.matches(l, false /* ignorePassword */))
+    ) {
+      this.addLoginToSummary(login, "no_change");
+      return true;
+    }
+    // Now check for a login with the same username, where it may be that we have an
+    // updated password.
+    let foundMatchingLogin = false;
+    for (let existingLogin of existingLogins) {
+      if (login.username == existingLogin.username) {
+        foundMatchingLogin = true;
+        existingLogin.QueryInterface(Ci.nsILoginMetaInfo);
+        if (
+          (login.password != existingLogin.password) &
+          (login.timePasswordChanged > existingLogin.timePasswordChanged)
+        ) {
+          // if a login with the same username and different password already exists and it's older
+          // than the current one, update its password and timestamp.
+          let propBag = Cc["@mozilla.org/hash-property-bag;1"].createInstance(
+            Ci.nsIWritablePropertyBag
+          );
+          propBag.setProperty("password", login.password);
+          propBag.setProperty("timePasswordChanged", login.timePasswordChanged);
+          this.addLoginToSummary({ ...existingLogin }, "modified", propBag);
+          return true;
+        }
+      }
+    }
+    // if the new login is an update or is older than an exiting login, don't add it.
+    if (foundMatchingLogin) {
+      this.addLoginToSummary(login, "no_change");
+      return true;
+    }
+    return false;
+  }
+
+  /**
+   * Validates if there are any invalid values using LoginHelper.checkLoginValues.
+   * If this is the case we mark it as "error" and return true.
+   * @param {object} login
+   *        A login object.
+   * @param {object} loginData
+   *        An vanilla object for the login without any methods.
+   * @returns {boolean} True if there is a validation error we return true, false otherwise.
+   */
+  checkLoginValuesError(login, loginData) {
+    try {
+      // Ensure we only send checked logins through, since the validation is optimized
+      // out from the bulk APIs below us.
+      LoginHelper.checkLoginValues(login);
+    } catch (e) {
+      this.addLoginToSummary({ ...loginData }, "error");
+      console.error(e);
+      return true;
+    }
+    return false;
+  }
+
+  /**
+   * Creates a new login from loginData.
+   * @param {object} loginData
+   *        An vanilla object for the login without any methods.
+   * @returns {object} A login object.
+   */
+  createNewLogin(loginData) {
+    let login = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(
+      Ci.nsILoginInfo
+    );
+    login.init(
+      loginData.origin,
+      loginData.formActionOrigin,
+      loginData.httpRealm,
+      loginData.username,
+      loginData.password,
+      loginData.usernameElement || "",
+      loginData.passwordElement || ""
+    );
+
+    login.QueryInterface(Ci.nsILoginMetaInfo);
+    login.timeCreated = loginData.timeCreated;
+    login.timeLastUsed = loginData.timeLastUsed || loginData.timeCreated;
+    login.timePasswordChanged =
+      loginData.timePasswordChanged || loginData.timeCreated;
+    login.timesUsed = loginData.timesUsed || 1;
+    login.guid = loginData.guid || null;
+    return login;
+  }
+
+  /**
+   * Cleans the action and realm field of the loginData.
+   * @param {object} loginData
+   *        An vanilla object for the login without any methods.
+   */
+  cleanupActionAndRealmFields(loginData) {
+    const cleanOrigin = loginData.formActionOrigin
+      ? LoginHelper.getLoginOrigin(loginData.formActionOrigin, true)
+      : "";
+    loginData.formActionOrigin =
+      cleanOrigin || (typeof loginData.httpRealm == "string" ? null : "");
+
+    loginData.httpRealm =
+      typeof loginData.httpRealm == "string" ? loginData.httpRealm : null;
+  }
+
+  /**
+   * Adds a login to the summary.
+   * @param {object} login
+   *        A login object.
+   * @param {string} result
+   *        The result type. One of "added", "modified", "error", "error_invalid_origin", "error_invalid_password" or "no_change".
+   * @param {object} propBag
+   *        An optional parameter with the properties bag.
+   * @returns {object} The row that was added.
+   */
+  addLoginToSummary(login, result, propBag) {
+    let rows = this.originToRows.get(login.origin) || [];
+    if (rows.length === 0) {
+      this.originToRows.set(login.origin, rows);
+    }
+    const newSummaryRow = { result, login, propBag };
+    rows.push(newSummaryRow);
+    this.summary.push(newSummaryRow);
+    return newSummaryRow;
+  }
+
+  /**
+   * Iterates over all then rows where more than two match the same origin. It mutates the internal state of the processor.
+   * It makes sure that if the `timePasswordChanged` field is present it will be used to decide if it's a "no_change" or "added".
+   * The entry with the oldest `timePasswordChanged` will be "added", the rest will be "no_change".
+   */
+  markLastTimePasswordChangedAsModified() {
+    const originUserToRowMap = new Map();
+    for (let currentRow of this.summary) {
+      if (
+        currentRow.result === "added" ||
+        currentRow.result === "modified" ||
+        currentRow.result === "no_change"
+      ) {
+        const originAndUser =
+          currentRow.login.origin + currentRow.login.username;
+        let lastTimeChangedRow = originUserToRowMap.get(originAndUser);
+        if (lastTimeChangedRow) {
+          if (
+            (currentRow.login.password != lastTimeChangedRow.login.password) &
+            (currentRow.login.timePasswordChanged >
+              lastTimeChangedRow.login.timePasswordChanged)
+          ) {
+            lastTimeChangedRow.result = "no_change";
+            currentRow.result = "added";
+            originUserToRowMap.set(originAndUser, currentRow);
+          }
+        } else {
+          originUserToRowMap.set(originAndUser, currentRow);
+        }
+      }
+    }
+  }
+
+  /**
+   * Iterates over all then rows where more than two match the same origin. It mutates the internal state of the processor.
+   * It makes sure that if the `timePasswordChanged` field is present it will be used to decide if it's a "no_change" or "added".
+   * The entry with the oldest `timePasswordChanged` will be "added", the rest will be "no_change".
+   * @returns {Object[]} An entry for each processed row containing how the row was processed and the login data.
+   */
+  async processLoginsAndBuildSummary() {
+    this.markLastTimePasswordChangedAsModified();
+    for (let summaryRow of this.summary) {
+      try {
+        if (summaryRow.result === "added") {
+          summaryRow.login = await Services.logins.addLoginAsync(
+            summaryRow.login
+          );
+        } else if (summaryRow.result === "modified") {
+          Services.logins.modifyLogin(summaryRow.login, summaryRow.propBag);
+        }
+      } catch (e) {
+        console.error(e);
+        summaryRow.result = "error";
+      }
+    }
+    return this.summary;
+  }
+}
+
+/**
+ * Contains functions shared by different Login Manager components.
+ */
+export const LoginHelper = {
+  debug: null,
+  enabled: null,
+  storageEnabled: null,
+  formlessCaptureEnabled: null,
+  formRemovalCaptureEnabled: null,
+  generationAvailable: null,
+  generationConfidenceThreshold: null,
+  generationEnabled: null,
+  improvedPasswordRulesEnabled: null,
+  improvedPasswordRulesCollection: "password-rules",
+  includeOtherSubdomainsInLookup: null,
+  insecureAutofill: null,
+  privateBrowsingCaptureEnabled: null,
+  remoteRecipesEnabled: null,
+  remoteRecipesCollection: "password-recipes",
+  relatedRealmsEnabled: null,
+  relatedRealmsCollection: "websites-with-shared-credential-backends",
+  schemeUpgrades: null,
+  showAutoCompleteFooter: null,
+  showAutoCompleteImport: null,
+  testOnlyUserHasInteractedWithDocument: null,
+  userInputRequiredToCapture: null,
+  captureInputChanges: null,
+
+  init() {
+    // Watch for pref changes to update cached pref values.
+    Services.prefs.addObserver("signon.", () => this.updateSignonPrefs());
+    this.updateSignonPrefs();
+    Services.telemetry.setEventRecordingEnabled("pwmgr", true);
+    Services.telemetry.setEventRecordingEnabled("form_autocomplete", true);
+
+    // Watch for FXA Logout to reset signon.firefoxRelay to 'available'
+    // Using hard-coded value for FxAccountsCommon.ONLOGOUT_NOTIFICATION because
+    // importing FxAccountsCommon here caused hard-to-diagnose crash.
+    Services.obs.addObserver(() => {
+      Services.prefs.clearUserPref("signon.firefoxRelay.feature");
+    }, "fxaccounts:onlogout");
+  },
+
+  updateSignonPrefs() {
+    this.autofillForms = Services.prefs.getBoolPref("signon.autofillForms");
+    this.autofillAutocompleteOff = Services.prefs.getBoolPref(
+      "signon.autofillForms.autocompleteOff"
+    );
+    this.captureInputChanges = Services.prefs.getBoolPref(
+      "signon.capture.inputChanges.enabled"
+    );
+    this.debug = Services.prefs.getBoolPref("signon.debug");
+    this.enabled = Services.prefs.getBoolPref("signon.rememberSignons");
+    this.storageEnabled = Services.prefs.getBoolPref(
+      "signon.storeSignons",
+      true
+    );
+    this.formlessCaptureEnabled = Services.prefs.getBoolPref(
+      "signon.formlessCapture.enabled"
+    );
+    this.formRemovalCaptureEnabled = Services.prefs.getBoolPref(
+      "signon.formRemovalCapture.enabled"
+    );
+    this.generationAvailable = Services.prefs.getBoolPref(
+      "signon.generation.available"
+    );
+    this.generationConfidenceThreshold = parseFloat(
+      Services.prefs.getStringPref("signon.generation.confidenceThreshold")
+    );
+    this.generationEnabled = Services.prefs.getBoolPref(
+      "signon.generation.enabled"
+    );
+    this.improvedPasswordRulesEnabled = Services.prefs.getBoolPref(
+      "signon.improvedPasswordRules.enabled"
+    );
+    this.insecureAutofill = Services.prefs.getBoolPref(
+      "signon.autofillForms.http"
+    );
+    this.includeOtherSubdomainsInLookup = Services.prefs.getBoolPref(
+      "signon.includeOtherSubdomainsInLookup"
+    );
+    this.passwordEditCaptureEnabled = Services.prefs.getBoolPref(
+      "signon.passwordEditCapture.enabled"
+    );
+    this.privateBrowsingCaptureEnabled = Services.prefs.getBoolPref(
+      "signon.privateBrowsingCapture.enabled"
+    );
+    this.schemeUpgrades = Services.prefs.getBoolPref("signon.schemeUpgrades");
+    this.showAutoCompleteFooter = Services.prefs.getBoolPref(
+      "signon.showAutoCompleteFooter"
+    );
+
+    this.showAutoCompleteImport = Services.prefs.getStringPref(
+      "signon.showAutoCompleteImport",
+      ""
+    );
+
+    this.storeWhenAutocompleteOff = Services.prefs.getBoolPref(
+      "signon.storeWhenAutocompleteOff"
+    );
+
+    this.suggestImportCount = Services.prefs.getIntPref(
+      "signon.suggestImportCount",
+      0
+    );
+
+    if (
+      Services.prefs.getBoolPref(
+        "signon.testOnlyUserHasInteractedByPrefValue",
+        false
+      )
+    ) {
+      this.testOnlyUserHasInteractedWithDocument = Services.prefs.getBoolPref(
+        "signon.testOnlyUserHasInteractedWithDocument",
+        false
+      );
+      lazy.log.debug(
+        `Using pref value for testOnlyUserHasInteractedWithDocument ${this.testOnlyUserHasInteractedWithDocument}.`
+      );
+    } else {
+      this.testOnlyUserHasInteractedWithDocument = null;
+    }
+
+    this.userInputRequiredToCapture = Services.prefs.getBoolPref(
+      "signon.userInputRequiredToCapture.enabled"
+    );
+    this.usernameOnlyFormEnabled = Services.prefs.getBoolPref(
+      "signon.usernameOnlyForm.enabled"
+    );
+    this.usernameOnlyFormLookupThreshold = Services.prefs.getIntPref(
+      "signon.usernameOnlyForm.lookupThreshold"
+    );
+    this.remoteRecipesEnabled = Services.prefs.getBoolPref(
+      "signon.recipes.remoteRecipes.enabled"
+    );
+    this.relatedRealmsEnabled = Services.prefs.getBoolPref(
+      "signon.relatedRealms.enabled"
+    );
+  },
+
+  createLogger(aLogPrefix) {
+    let getMaxLogLevel = () => {
+      return this.debug ? "Debug" : "Warn";
+    };
+
+    // Create a new instance of the ConsoleAPI so we can control the maxLogLevel with a pref.
+    let consoleOptions = {
+      maxLogLevel: getMaxLogLevel(),
+      prefix: aLogPrefix,
+    };
+    let logger = console.createInstance(consoleOptions);
+
+    // Watch for pref changes and update this.debug and the maxLogLevel for created loggers
+    Services.prefs.addObserver("signon.debug", () => {
+      this.debug = Services.prefs.getBoolPref("signon.debug");
+      if (logger) {
+        logger.maxLogLevel = getMaxLogLevel();
+      }
+    });
+
+    return logger;
+  },
+
+  /**
+   * Due to the way the signons2.txt file is formatted, we need to make
+   * sure certain field values or characters do not cause the file to
+   * be parsed incorrectly.  Reject origins that we can't store correctly.
+   *
+   * @throws String with English message in case validation failed.
+   */
+  checkOriginValue(aOrigin) {
+    // Nulls are invalid, as they don't round-trip well.  Newlines are also
+    // invalid for any field stored as plaintext, and an origin made of a
+    // single dot cannot be stored in the legacy format.
+    if (
+      aOrigin == "." ||
+      aOrigin.includes("\r") ||
+      aOrigin.includes("\n") ||
+      aOrigin.includes("\0")
+    ) {
+      throw new Error("Invalid origin");
+    }
+  },
+
+  /**
+   * Due to the way the signons2.txt file was formatted, we needed to make
+   * sure certain field values or characters do not cause the file to
+   * be parsed incorrectly. These characters can cause problems in other
+   * formats/languages too so reject logins that may not be stored correctly.
+   *
+   * @throws String with English message in case validation failed.
+   */
+  checkLoginValues(aLogin) {
+    function badCharacterPresent(l, c) {
+      return (
+        (l.formActionOrigin && l.formActionOrigin.includes(c)) ||
+        (l.httpRealm && l.httpRealm.includes(c)) ||
+        l.origin.includes(c) ||
+        l.usernameField.includes(c) ||
+        l.passwordField.includes(c)
+      );
+    }
+
+    // Nulls are invalid, as they don't round-trip well.
+    // Mostly not a formatting problem, although ".\0" can be quirky.
+    if (badCharacterPresent(aLogin, "\0")) {
+      throw new Error("login values can't contain nulls");
+    }
+
+    if (!aLogin.password || typeof aLogin.password != "string") {
+      throw new Error("passwords must be non-empty strings");
+    }
+
+    // In theory these nulls should just be rolled up into the encrypted
+    // values, but nsISecretDecoderRing doesn't use nsStrings, so the
+    // nulls cause truncation. Check for them here just to avoid
+    // unexpected round-trip surprises.
+    if (aLogin.username.includes("\0") || aLogin.password.includes("\0")) {
+      throw new Error("login values can't contain nulls");
+    }
+
+    // Newlines are invalid for any field stored as plaintext.
+    if (
+      badCharacterPresent(aLogin, "\r") ||
+      badCharacterPresent(aLogin, "\n")
+    ) {
+      throw new Error("login values can't contain newlines");
+    }
+
+    // A line with just a "." can have special meaning.
+    if (aLogin.usernameField == "." || aLogin.formActionOrigin == ".") {
+      throw new Error("login values can't be periods");
+    }
+
+    // An origin with "\ \(" won't roundtrip.
+    // eg host="foo (", realm="bar" --> "foo ( (bar)"
+    // vs host="foo", realm=" (bar" --> "foo ( (bar)"
+    if (aLogin.origin.includes(" (")) {
+      throw new Error("bad parens in origin");
+    }
+  },
+
+  /**
+   * Returns a new XPCOM property bag with the provided properties.
+   *
+   * @param {Object} aProperties
+   *        Each property of this object is copied to the property bag.  This
+   *        parameter can be omitted to return an empty property bag.
+   *
+   * @return A new property bag, that is an instance of nsIWritablePropertyBag,
+   *         nsIWritablePropertyBag2, nsIPropertyBag, and nsIPropertyBag2.
+   */
+  newPropertyBag(aProperties) {
+    let propertyBag = Cc["@mozilla.org/hash-property-bag;1"].createInstance(
+      Ci.nsIWritablePropertyBag
+    );
+    if (aProperties) {
+      for (let [name, value] of Object.entries(aProperties)) {
+        propertyBag.setProperty(name, value);
+      }
+    }
+    return propertyBag
+      .QueryInterface(Ci.nsIPropertyBag)
+      .QueryInterface(Ci.nsIPropertyBag2)
+      .QueryInterface(Ci.nsIWritablePropertyBag2);
+  },
+
+  /**
+   * Helper to avoid the property bags when calling
+   * Services.logins.searchLogins from JS.
+   * @deprecated Use Services.logins.searchLoginsAsync instead.
+   *
+   * @param {Object} aSearchOptions - A regular JS object to copy to a property bag before searching
+   * @return {nsILoginInfo[]} - The result of calling searchLogins.
+   */
+  searchLoginsWithObject(aSearchOptions) {
+    return Services.logins.searchLogins(this.newPropertyBag(aSearchOptions));
+  },
+
+  /**
+   * @param {string} aURL
+   * @returns {string} which is the hostPort of aURL if supported by the scheme
+   *                   otherwise, returns the original aURL.
+   */
+  maybeGetHostPortForURL(aURL) {
+    try {
+      let uri = Services.io.newURI(aURL);
+      return uri.hostPort;
+    } catch (ex) {
+      // No need to warn for javascript:/data:/about:/chrome:/etc.
+    }
+    return aURL;
+  },
+
+  /**
+   * Get the parts of the URL we want for identification.
+   * Strip out things like the userPass portion and handle javascript:.
+   */
+  getLoginOrigin(uriString, allowJS = false) {
+    try {
+      const mozProxyRegex = /^moz-proxy:\/\//i;
+      const isMozProxy = !!uriString.match(mozProxyRegex);
+      if (isMozProxy) {
+        // Special handling because uri.displayHostPort throws on moz-proxy://
+        return (
+          "moz-proxy://" +
+          Services.io.newURI(uriString.replace(mozProxyRegex, "https://"))
+            .displayHostPort
+        );
+      }
+
+      const uri = Services.io.newURI(uriString);
+      if (allowJS && uri.scheme == "javascript") {
+        return "javascript:";
+      }
+
+      // Build this manually instead of using prePath to avoid including the userPass portion.
+      return uri.scheme + "://" + uri.displayHostPort;
+    } catch {
+      return null;
+    }
+  },
+
+  getFormActionOrigin(form) {
+    let uriString = form.action;
+
+    // A blank or missing action submits to where it came from.
+    if (uriString == "") {
+      // ala bug 297761
+      uriString = form.baseURI;
+    }
+
+    return this.getLoginOrigin(uriString, true);
+  },
+
+  /**
+   * @param {String} aLoginOrigin - An origin value from a stored login's
+   *                                origin or formActionOrigin properties.
+   * @param {String} aSearchOrigin - The origin that was are looking to match
+   *                                 with aLoginOrigin. This would normally come
+   *                                 from a form or page that we are considering.
+   * @param {nsILoginFindOptions} aOptions - Options to affect whether the origin
+   *                                         from the login (aLoginOrigin) is a
+   *                                         match for the origin we're looking
+   *                                         for (aSearchOrigin).
+   */
+  isOriginMatching(
+    aLoginOrigin,
+    aSearchOrigin,
+    aOptions = {
+      schemeUpgrades: false,
+      acceptWildcardMatch: false,
+      acceptDifferentSubdomains: false,
+      acceptRelatedRealms: false,
+      relatedRealms: [],
+    }
+  ) {
+    if (aLoginOrigin == aSearchOrigin) {
+      return true;
+    }
+
+    if (!aOptions) {
+      return false;
+    }
+
+    if (aOptions.acceptWildcardMatch && aLoginOrigin == "") {
+      return true;
+    }
+
+    // We can only match logins now if either of these flags are true, so
+    // avoid doing the work of constructing URL objects if neither is true.
+    if (!aOptions.acceptDifferentSubdomains && !aOptions.schemeUpgrades) {
+      return false;
+    }
+
+    try {
+      let loginURI = Services.io.newURI(aLoginOrigin);
+      let searchURI = Services.io.newURI(aSearchOrigin);
+      let schemeMatches =
+        loginURI.scheme == "http" && searchURI.scheme == "https";
+
+      if (aOptions.acceptDifferentSubdomains) {
+        let loginBaseDomain = Services.eTLD.getBaseDomain(loginURI);
+        let searchBaseDomain = Services.eTLD.getBaseDomain(searchURI);
+        if (
+          loginBaseDomain == searchBaseDomain &&
+          (loginURI.scheme == searchURI.scheme ||
+            (aOptions.schemeUpgrades && schemeMatches))
+        ) {
+          return true;
+        }
+        if (
+          aOptions.acceptRelatedRealms &&
+          aOptions.relatedRealms.length &&
+          (loginURI.scheme == searchURI.scheme ||
+            (aOptions.schemeUpgrades && schemeMatches))
+        ) {
+          for (let relatedOrigin of aOptions.relatedRealms) {
+            if (Services.eTLD.hasRootDomain(loginURI.host, relatedOrigin)) {
+              return true;
+            }
+          }
+        }
+      }
+
+      if (
+        aOptions.schemeUpgrades &&
+        loginURI.host == searchURI.host &&
+        schemeMatches &&
+        loginURI.port == searchURI.port
+      ) {
+        return true;
+      }
+    } catch (ex) {
+      // newURI will throw for some values e.g. chrome://FirefoxAccounts
+      // uri.host and uri.port will throw for some values e.g. javascript:
+      return false;
+    }
+
+    return false;
+  },
+
+  doLoginsMatch(
+    aLogin1,
+    aLogin2,
+    { ignorePassword = false, ignoreSchemes = false }
+  ) {
+    if (
+      aLogin1.httpRealm != aLogin2.httpRealm ||
+      aLogin1.username != aLogin2.username
+    ) {
+      return false;
+    }
+
+    if (!ignorePassword && aLogin1.password != aLogin2.password) {
+      return false;
+    }
+
+    if (ignoreSchemes) {
+      let login1HostPort = this.maybeGetHostPortForURL(aLogin1.origin);
+      let login2HostPort = this.maybeGetHostPortForURL(aLogin2.origin);
+      if (login1HostPort != login2HostPort) {
+        return false;
+      }
+
+      if (
+        aLogin1.formActionOrigin != "" &&
+        aLogin2.formActionOrigin != "" &&
+        this.maybeGetHostPortForURL(aLogin1.formActionOrigin) !=
+          this.maybeGetHostPortForURL(aLogin2.formActionOrigin)
+      ) {
+        return false;
+      }
+    } else {
+      if (aLogin1.origin != aLogin2.origin) {
+        return false;
+      }
+
+      // If either formActionOrigin is blank (but not null), then match.
+      if (
+        aLogin1.formActionOrigin != "" &&
+        aLogin2.formActionOrigin != "" &&
+        aLogin1.formActionOrigin != aLogin2.formActionOrigin
+      ) {
+        return false;
+      }
+    }
+
+    // The .usernameField and .passwordField values are ignored.
+
+    return true;
+  },
+
+  /**
+   * Creates a new login object that results by modifying the given object with
+   * the provided data.
+   *
+   * @param {nsILoginInfo} aOldStoredLogin
+   *        Existing login object to modify.
+   * @param {nsILoginInfo|nsIProperyBag} aNewLoginData
+   *        The new login values, either as an nsILoginInfo or nsIProperyBag.
+   *
+   * @return {nsILoginInfo} The newly created nsILoginInfo object.
+   *
+   * @throws {Error} With English message in case validation failed.
+   */
+  buildModifiedLogin(aOldStoredLogin, aNewLoginData) {
+    function bagHasProperty(aPropName) {
+      try {
+        aNewLoginData.getProperty(aPropName);
+        return true;
+      } catch (ex) {}
+      return false;
+    }
+
+    aOldStoredLogin.QueryInterface(Ci.nsILoginMetaInfo);
+
+    let newLogin;
+    if (aNewLoginData instanceof Ci.nsILoginInfo) {
+      // Clone the existing login to get its nsILoginMetaInfo, then init it
+      // with the replacement nsILoginInfo data from the new login.
+      newLogin = aOldStoredLogin.clone();
+      newLogin.init(
+        aNewLoginData.origin,
+        aNewLoginData.formActionOrigin,
+        aNewLoginData.httpRealm,
+        aNewLoginData.username,
+        aNewLoginData.password,
+        aNewLoginData.usernameField,
+        aNewLoginData.passwordField
+      );
+      newLogin.unknownFields = aNewLoginData.unknownFields;
+      newLogin.QueryInterface(Ci.nsILoginMetaInfo);
+
+      // Automatically update metainfo when password is changed.
+      if (newLogin.password != aOldStoredLogin.password) {
+        newLogin.timePasswordChanged = Date.now();
+      }
+    } else if (aNewLoginData instanceof Ci.nsIPropertyBag) {
+      // Clone the existing login, along with all its properties.
+      newLogin = aOldStoredLogin.clone();
+      newLogin.QueryInterface(Ci.nsILoginMetaInfo);
+
+      // Automatically update metainfo when password is changed.
+      // (Done before the main property updates, lest the caller be
+      // explicitly updating both .password and .timePasswordChanged)
+      if (bagHasProperty("password")) {
+        let newPassword = aNewLoginData.getProperty("password");
+        if (newPassword != aOldStoredLogin.password) {
+          newLogin.timePasswordChanged = Date.now();
+        }
+      }
+
+      for (let prop of aNewLoginData.enumerator) {
+        switch (prop.name) {
+          // nsILoginInfo (fall through)
+          case "origin":
+          case "httpRealm":
+          case "formActionOrigin":
+          case "username":
+          case "password":
+          case "usernameField":
+          case "passwordField":
+          case "unknownFields":
+          // nsILoginMetaInfo (fall through)
+          case "guid":
+          case "timeCreated":
+          case "timeLastUsed":
+          case "timePasswordChanged":
+          case "timesUsed":
+            newLogin[prop.name] = prop.value;
+            break;
+
+          // Fake property, allows easy incrementing.
+          case "timesUsedIncrement":
+            newLogin.timesUsed += prop.value;
+            break;
+
+          // Fail if caller requests setting an unknown property.
+          default:
+            throw new Error("Unexpected propertybag item: " + prop.name);
+        }
+      }
+    } else {
+      throw new Error("newLoginData needs an expected interface!");
+    }
+
+    // Sanity check the login
+    if (newLogin.origin == null || !newLogin.origin.length) {
+      throw new Error("Can't add a login with a null or empty origin.");
+    }
+
+    // For logins w/o a username, set to "", not null.
+    if (newLogin.username == null) {
+      throw new Error("Can't add a login with a null username.");
+    }
+
+    if (newLogin.password == null || !newLogin.password.length) {
+      throw new Error("Can't add a login with a null or empty password.");
+    }
+
+    if (newLogin.formActionOrigin || newLogin.formActionOrigin == "") {
+      // We have a form submit URL. Can't have a HTTP realm.
+      if (newLogin.httpRealm != null) {
+        throw new Error(
+          "Can't add a login with both a httpRealm and formActionOrigin."
+        );
+      }
+    } else if (newLogin.httpRealm || newLogin.httpRealm == "") {
+      // We have a HTTP realm. Can't have a form submit URL.
+      if (newLogin.formActionOrigin != null) {
+        throw new Error(
+          "Can't add a login with both a httpRealm and formActionOrigin."
+        );
+      }
+    } else {
+      // Need one or the other!
+      throw new Error(
+        "Can't add a login without a httpRealm or formActionOrigin."
+      );
+    }
+
+    // Throws if there are bogus values.
+    this.checkLoginValues(newLogin);
+
+    return newLogin;
+  },
+
+  /**
+   * Remove http: logins when there is an https: login with the same username and hostPort.
+   * Sort order is preserved.
+   *
+   * @param {nsILoginInfo[]} logins
+   *        A list of logins we want to process for shadowing.
+   * @returns {nsILoginInfo[]} A subset of of the passed logins.
+   */
+  shadowHTTPLogins(logins) {
+    /**
+     * Map a (hostPort, username) to a boolean indicating whether `logins`
+     * contains an https: login for that combo.
+     */
+    let hasHTTPSByHostPortUsername = new Map();
+    for (let login of logins) {
+      let key = this.getUniqueKeyForLogin(login, ["hostPort", "username"]);
+      let hasHTTPSlogin = hasHTTPSByHostPortUsername.get(key) || false;
+      let loginURI = Services.io.newURI(login.origin);
+      hasHTTPSByHostPortUsername.set(
+        key,
+        loginURI.scheme == "https" || hasHTTPSlogin
+      );
+    }
+
+    return logins.filter(login => {
+      let key = this.getUniqueKeyForLogin(login, ["hostPort", "username"]);
+      let loginURI = Services.io.newURI(login.origin);
+      if (loginURI.scheme == "http" && hasHTTPSByHostPortUsername.get(key)) {
+        // If this is an http: login and we have an https: login for the
+        // (hostPort, username) combo then remove it.
+        return false;
+      }
+      return true;
+    });
+  },
+
+  /**
+   * Generate a unique key string from a login.
+   * @param {nsILoginInfo} login
+   * @param {string[]} uniqueKeys containing nsILoginInfo attribute names or "hostPort"
+   * @returns {string} to use as a key in a Map
+   */
+  getUniqueKeyForLogin(login, uniqueKeys) {
+    const KEY_DELIMITER = ":";
+    return uniqueKeys.reduce((prev, key) => {
+      let val = null;
+      if (key == "hostPort") {
+        val = Services.io.newURI(login.origin).hostPort;
+      } else {
+        val = login[key];
+      }
+
+      return prev + KEY_DELIMITER + val;
+    }, "");
+  },
+
+  /**
+   * Removes duplicates from a list of logins while preserving the sort order.
+   *
+   * @param {nsILoginInfo[]} logins
+   *        A list of logins we want to deduplicate.
+   * @param {string[]} [uniqueKeys = ["username", "password"]]
+   *        A list of login attributes to use as unique keys for the deduplication.
+   * @param {string[]} [resolveBy = ["timeLastUsed"]]
+   *        Ordered array of keyword strings used to decide which of the
+   *        duplicates should be used. "scheme" would prefer the login that has
+   *        a scheme matching `preferredOrigin`'s if there are two logins with
+   *        the same `uniqueKeys`. The default preference to distinguish two
+   *        logins is `timeLastUsed`. If there is no preference between two
+   *        logins, the first one found wins.
+   * @param {string} [preferredOrigin = undefined]
+   *        String representing the origin to use for preferring one login over
+   *        another when they are dupes. This is used with "scheme" for
+   *        `resolveBy` so the scheme from this origin will be preferred.
+   * @param {string} [preferredFormActionOrigin = undefined]
+   *        String representing the action origin to use for preferring one login over
+   *        another when they are dupes. This is used with "actionOrigin" for
+   *        `resolveBy` so the scheme from this action origin will be preferred.
+   *
+   * @returns {nsILoginInfo[]} list of unique logins.
+   */
+  dedupeLogins(
+    logins,
+    uniqueKeys = ["username", "password"],
+    resolveBy = ["timeLastUsed"],
+    preferredOrigin = undefined,
+    preferredFormActionOrigin = undefined
+  ) {
+    if (!preferredOrigin) {
+      if (resolveBy.includes("scheme")) {
+        throw new Error(
+          "dedupeLogins: `preferredOrigin` is required in order to " +
+            "prefer schemes which match it."
+        );
+      }
+      if (resolveBy.includes("subdomain")) {
+        throw new Error(
+          "dedupeLogins: `preferredOrigin` is required in order to " +
+            "prefer subdomains which match it."
+        );
+      }
+    }
+
+    let preferredOriginScheme;
+    if (preferredOrigin) {
+      try {
+        preferredOriginScheme = Services.io.newURI(preferredOrigin).scheme;
+      } catch (ex) {
+        // Handle strings that aren't valid URIs e.g. chrome://FirefoxAccounts
+      }
+    }
+
+    if (!preferredOriginScheme && resolveBy.includes("scheme")) {
+      lazy.log.warn(
+        "Deduping with a scheme preference but couldn't get the preferred origin scheme."
+      );
+    }
+
+    // We use a Map to easily lookup logins by their unique keys.
+    let loginsByKeys = new Map();
+
+    /**
+     * @return {bool} whether `login` is preferred over its duplicate (considering `uniqueKeys`)
+     *                `existingLogin`.
+     *
+     * `resolveBy` is a sorted array so we can return true the first time `login` is preferred
+     * over the existingLogin.
+     */
+    function isLoginPreferred(existingLogin, login) {
+      if (!resolveBy || !resolveBy.length) {
+        // If there is no preference, prefer the existing login.
+        return false;
+      }
+
+      for (let preference of resolveBy) {
+        switch (preference) {
+          case "actionOrigin": {
+            if (!preferredFormActionOrigin) {
+              break;
+            }
+            if (
+              LoginHelper.isOriginMatching(
+                existingLogin.formActionOrigin,
+                preferredFormActionOrigin,
+                { schemeUpgrades: LoginHelper.schemeUpgrades }
+              ) &&
+              !LoginHelper.isOriginMatching(
+                login.formActionOrigin,
+                preferredFormActionOrigin,
+                { schemeUpgrades: LoginHelper.schemeUpgrades }
+              )
+            ) {
+              return false;
+            }
+            break;
+          }
+          case "scheme": {
+            if (!preferredOriginScheme) {
+              break;
+            }
+
+            try {
+              // Only `origin` is currently considered
+              let existingLoginURI = Services.io.newURI(existingLogin.origin);
+              let loginURI = Services.io.newURI(login.origin);
+              // If the schemes of the two logins are the same or neither match the
+              // preferredOriginScheme then we have no preference and look at the next resolveBy.
+              if (
+                loginURI.scheme == existingLoginURI.scheme ||
+                (loginURI.scheme != preferredOriginScheme &&
+                  existingLoginURI.scheme != preferredOriginScheme)
+              ) {
+                break;
+              }
+
+              return loginURI.scheme == preferredOriginScheme;
+            } catch (e) {
+              // Some URLs aren't valid nsIURI (e.g. chrome://FirefoxAccounts)
+              lazy.log.debug(
+                "dedupeLogins/shouldReplaceExisting: Error comparing schemes:",
+                existingLogin.origin,
+                login.origin,
+                "preferredOrigin:",
+                preferredOrigin,
+                e.name
+              );
+            }
+            break;
+          }
+          case "subdomain": {
+            // Replace the existing login only if the new login is an exact match on the host.
+            let existingLoginURI = Services.io.newURI(existingLogin.origin);
+            let newLoginURI = Services.io.newURI(login.origin);
+            let preferredOriginURI = Services.io.newURI(preferredOrigin);
+            if (
+              existingLoginURI.hostPort != preferredOriginURI.hostPort &&
+              newLoginURI.hostPort == preferredOriginURI.hostPort
+            ) {
+              return true;
+            }
+            if (
+              existingLoginURI.host != preferredOriginURI.host &&
+              newLoginURI.host == preferredOriginURI.host
+            ) {
+              return true;
+            }
+            // if the existing login host *is* a match and the new one isn't
+            // we explicitly want to keep the existing one
+            if (
+              existingLoginURI.host == preferredOriginURI.host &&
+              newLoginURI.host != preferredOriginURI.host
+            ) {
+              return false;
+            }
+            break;
+          }
+          case "timeLastUsed":
+          case "timePasswordChanged": {
+            // If we find a more recent login for the same key, replace the existing one.
+            let loginDate = login.QueryInterface(Ci.nsILoginMetaInfo)[
+              preference
+            ];
+            let storedLoginDate = existingLogin.QueryInterface(
+              Ci.nsILoginMetaInfo
+            )[preference];
+            if (loginDate == storedLoginDate) {
+              break;
+            }
+
+            return loginDate > storedLoginDate;
+          }
+          default: {
+            throw new Error(
+              "dedupeLogins: Invalid resolveBy preference: " + preference
+            );
+          }
+        }
+      }
+
+      return false;
+    }
+
+    for (let login of logins) {
+      let key = this.getUniqueKeyForLogin(login, uniqueKeys);
+
+      if (loginsByKeys.has(key)) {
+        if (!isLoginPreferred(loginsByKeys.get(key), login)) {
+          // If there is no preference for the new login, use the existing one.
+          continue;
+        }
+      }
+      loginsByKeys.set(key, login);
+    }
+
+    // Return the map values in the form of an array.
+    return [...loginsByKeys.values()];
+  },
+
+  /**
+   * Open the password manager window.
+   *
+   * @param {Window} window
+   *                 the window from where we want to open the dialog
+   *
+   * @param {object?} args
+   *                  params for opening the password manager
+   * @param {string} [args.filterString=""]
+   *                 the domain (not origin) to pass to the login manager dialog
+   *                 to pre-filter the results
+   * @param {string} args.entryPoint
+   *                 The name of the entry point, used for telemetry
+   */
+  openPasswordManager(
+    window,
+    { filterString = "", entryPoint = "", loginGuid = null } = {}
+  ) {
+    // Get currently active tab's origin
+    const openedFrom =
+      window.gBrowser?.selectedTab.linkedBrowser.currentURI.spec;
+    // If no loginGuid is set, get sanitized origin, this will return null for about:* uris
+    const preselectedLogin = loginGuid ?? this.getLoginOrigin(openedFrom);
+
+    const params = new URLSearchParams({
+      ...(filterString && { filter: filterString }),
+      ...(entryPoint && { entryPoint }),
+    });
+
+    const paramsPart = params.toString() ? `?${params}` : "";
+
+    const browser = window.gBrowser ?? window.opener?.gBrowser;
+
+    const tab = browser.addTrustedTab(`about:logins${paramsPart}`, {
+      inBackground: false,
+    });
+
+    tab.setAttribute("preselect-login", preselectedLogin);
+  },
+
+  /**
+   * Checks if a field type is password compatible.
+   *
+   * @param {Element} element
+   *                  the field we want to check.
+   * @param {Object} options
+   * @param {bool} [options.ignoreConnect] - Whether to ignore checking isConnected
+   *                                         of the element.
+   *
+   * @returns {Boolean} true if the field can
+   *                    be treated as a password input
+   */
+  isPasswordFieldType(element, { ignoreConnect = false } = {}) {
+    if (!HTMLInputElement.isInstance(element)) {
+      return false;
+    }
+
+    if (!element.isConnected && !ignoreConnect) {
+      // If the element isn't connected then it isn't visible to the user so
+      // shouldn't be considered. It must have been connected in the past.
+      return false;
+    }
+
+    if (!element.hasBeenTypePassword) {
+      return false;
+    }
+
+    // Ensure the element is of a type that could have autocomplete.
+    // These include the types with user-editable values. If not, even if it used to be
+    // a type=password, we can't treat it as a password input now
+    let acInfo = element.getAutocompleteInfo();
+    if (!acInfo) {
+      return false;
+    }
+
+    return true;
+  },
+
+  /**
+   * Checks if a field type is username compatible.
+   *
+   * @param {Element} element
+   *                  the field we want to check.
+   * @param {Object} options
+   * @param {bool} [options.ignoreConnect] - Whether to ignore checking isConnected
+   *                                         of the element.
+   *
+   * @returns {Boolean} true if the field type is one
+   *                    of the username types.
+   */
+  isUsernameFieldType(element, { ignoreConnect = false } = {}) {
+    if (!HTMLInputElement.isInstance(element)) {
+      return false;
+    }
+
+    if (!element.isConnected && !ignoreConnect) {
+      // If the element isn't connected then it isn't visible to the user so
+      // shouldn't be considered. It must have been connected in the past.
+      return false;
+    }
+
+    if (element.hasBeenTypePassword) {
+      return false;
+    }
+
+    if (!Logic.inputTypeIsCompatibleWithUsername(element)) {
+      return false;
+    }
+
+    let acFieldName = element.getAutocompleteInfo().fieldName;
+    if (
+      !(
+        acFieldName == "username" ||
+        acFieldName == "webauthn" ||
+        // Bug 1540154: Some sites use tel/email on their username fields.
+        acFieldName == "email" ||
+        acFieldName == "tel" ||
+        acFieldName == "tel-national" ||
+        acFieldName == "off" ||
+        acFieldName == "on" ||
+        acFieldName == ""
+      )
+    ) {
+      return false;
+    }
+    return true;
+  },
+
+  /**
+   * Infer whether a form is a sign-in form by searching keywords
+   * in its attributes
+   *
+   * @param {Element} element
+   *                  the form we want to check.
+   *
+   * @returns {boolean} True if any of the rules matches
+   */
+  isInferredLoginForm(formElement) {
+    // This is copied from 'loginFormAttrRegex' in NewPasswordModel.jsm
+    const loginExpr =
+      /login|log in|log on|log-on|sign in|sigin|sign\/in|sign-in|sign on|sign-on/i;
+
+    if (Logic.elementAttrsMatchRegex(formElement, loginExpr)) {
+      return true;
+    }
+
+    return false;
+  },
+
+  /**
+   * Infer whether an input field is a username field by searching
+   * 'username' keyword in its attributes
+   *
+   * @param {Element} element
+   *                  the field we want to check.
+   *
+   * @returns {boolean} True if any of the rules matches
+   */
+  isInferredUsernameField(element) {
+    const expr = /username/i;
+
+    let ac = element.getAutocompleteInfo()?.fieldName;
+    if (ac && ac == "username") {
+      return true;
+    }
+
+    if (
+      Logic.elementAttrsMatchRegex(element, expr) ||
+      Logic.hasLabelMatchingRegex(element, expr)
+    ) {
+      return true;
+    }
+
+    return false;
+  },
+
+  /**
+   * Search for keywords that indicates the input field is not likely a
+   * field of a username login form.
+   *
+   * @param {Element} element
+   *                  the input field we want to check.
+   *
+   * @returns {boolean} True if any of the rules matches
+   */
+  isInferredNonUsernameField(element) {
+    const expr = /search|code/i;
+
+    if (
+      Logic.elementAttrsMatchRegex(element, expr) ||
+      Logic.hasLabelMatchingRegex(element, expr)
+    ) {
+      return true;
+    }
+
+    return false;
+  },
+
+  /**
+   * Infer whether an input field is an email field by searching
+   * 'email' keyword in its attributes.
+   *
+   * @param {Element} element
+   *                  the field we want to check.
+   *
+   * @returns {boolean} True if any of the rules matches
+   */
+  isInferredEmailField(element) {
+    const expr = /email|邮箱/i;
+
+    if (element.type == "email") {
+      return true;
+    }
+
+    let ac = element.getAutocompleteInfo()?.fieldName;
+    if (ac && ac == "email") {
+      return true;
+    }
+
+    if (
+      Logic.elementAttrsMatchRegex(element, expr) ||
+      Logic.hasLabelMatchingRegex(element, expr)
+    ) {
+      return true;
+    }
+
+    return false;
+  },
+
+  /**
+   * For each login, add the login to the password manager if a similar one
+   * doesn't already exist. Merge it otherwise with the similar existing ones.
+   *
+   * @param {Object[]} loginDatas - For each login, the data that needs to be added.
+   * @returns {Object[]} An entry for each processed row containing how the row was processed and the login data.
+   */
+  async maybeImportLogins(loginDatas) {
+    this.importing = true;
+    try {
+      const processor = new ImportRowProcessor();
+      for (let rawLoginData of loginDatas) {
+        // Do some sanitization on a clone of the loginData.
+        let loginData = ChromeUtils.shallowClone(rawLoginData);
+        if (processor.checkNonUniqueGuidError(loginData)) {
+          continue;
+        }
+        if (processor.checkMissingMandatoryFieldsError(loginData)) {
+          continue;
+        }
+        processor.cleanupActionAndRealmFields(loginData);
+        if (await processor.checkExistingEntry(loginData)) {
+          continue;
+        }
+        let login = processor.createNewLogin(loginData);
+        if (processor.checkLoginValuesError(login, loginData)) {
+          continue;
+        }
+        if (processor.checkConflictingOriginWithPreviousRows(login)) {
+          continue;
+        }
+        if (await processor.checkConflictingWithExistingLogins(login)) {
+          continue;
+        }
+        processor.addLoginToSummary(login, "added");
+      }
+      return await processor.processLoginsAndBuildSummary();
+    } finally {
+      this.importing = false;
+
+      Services.obs.notifyObservers(null, "passwordmgr-reload-all");
+      this.notifyStorageChanged("importLogins", []);
+    }
+  },
+
+  /**
+   * Convert an array of nsILoginInfo to vanilla JS objects suitable for
+   * sending over IPC. Avoid using this in other cases.
+   *
+   * NB: All members of nsILoginInfo (not nsILoginMetaInfo) are strings.
+   */
+  loginsToVanillaObjects(logins) {
+    return logins.map(this.loginToVanillaObject);
+  },
+
+  /**
+   * Same as above, but for a single login.
+   */
+  loginToVanillaObject(login) {
+    let obj = {};
+    for (let i in login.QueryInterface(Ci.nsILoginMetaInfo)) {
+      if (typeof login[i] !== "function") {
+        obj[i] = login[i];
+      }
+    }
+    return obj;
+  },
+
+  /**
+   * Convert an object received from IPC into an nsILoginInfo (with guid).
+   */
+  vanillaObjectToLogin(login) {
+    let formLogin = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(
+      Ci.nsILoginInfo
+    );
+    formLogin.init(
+      login.origin,
+      login.formActionOrigin,
+      login.httpRealm,
+      login.username,
+      login.password,
+      login.usernameField,
+      login.passwordField
+    );
+
+    formLogin.QueryInterface(Ci.nsILoginMetaInfo);
+    for (let prop of [
+      "guid",
+      "timeCreated",
+      "timeLastUsed",
+      "timePasswordChanged",
+      "timesUsed",
+    ]) {
+      formLogin[prop] = login[prop];
+    }
+    return formLogin;
+  },
+
+  /**
+   * As above, but for an array of objects.
+   */
+  vanillaObjectsToLogins(vanillaObjects) {
+    const logins = [];
+    for (const vanillaObject of vanillaObjects) {
+      logins.push(this.vanillaObjectToLogin(vanillaObject));
+    }
+    return logins;
+  },
+
+  /**
+   * Returns true if the user has a primary password set and false otherwise.
+   */
+  isPrimaryPasswordSet() {
+    let tokenDB = Cc["@mozilla.org/security/pk11tokendb;1"].getService(
+      Ci.nsIPK11TokenDB
+    );
+    let token = tokenDB.getInternalKeyToken();
+    return token.hasPassword;
+  },
+
+  /**
+   * Shows the Primary Password prompt if enabled, or the
+   * OS auth dialog otherwise.
+   * @param {Element} browser
+   *        The <browser> that the prompt should be shown on
+   * @param OSReauthEnabled Boolean indicating if OS reauth should be tried
+   * @param expirationTime Optional timestamp indicating next required re-authentication
+   * @param messageText Formatted and localized string to be displayed when the OS auth dialog is used.
+   * @param captionText Formatted and localized string to be displayed when the OS auth dialog is used.
+   */
+  async requestReauth(
+    browser,
+    OSReauthEnabled,
+    expirationTime,
+    messageText,
+    captionText
+  ) {
+    let isAuthorized = false;
+    let telemetryEvent;
+
+    // This does no harm if primary password isn't set.
+    let tokendb = Cc["@mozilla.org/security/pk11tokendb;1"].createInstance(
+      Ci.nsIPK11TokenDB
+    );
+    let token = tokendb.getInternalKeyToken();
+
+    // Do we have a recent authorization?
+    if (expirationTime && Date.now() < expirationTime) {
+      isAuthorized = true;
+      telemetryEvent = {
+        object: token.hasPassword ? "master_password" : "os_auth",
+        method: "reauthenticate",
+        value: "success_no_prompt",
+      };
+      return {
+        isAuthorized,
+        telemetryEvent,
+      };
+    }
+
+    // Default to true if there is no primary password and OS reauth is not available
+    if (!token.hasPassword && !OSReauthEnabled) {
+      isAuthorized = true;
+      telemetryEvent = {
+        object: "os_auth",
+        method: "reauthenticate",
+        value: "success_disabled",
+      };
+      return {
+        isAuthorized,
+        telemetryEvent,
+      };
+    }
+    // Use the OS auth dialog if there is no primary password
+    if (!token.hasPassword && OSReauthEnabled) {
+      let result = await lazy.OSKeyStore.ensureLoggedIn(
+        messageText,
+        captionText,
+        browser.ownerGlobal,
+        false
+      );
+      isAuthorized = result.authenticated;
+      telemetryEvent = {
+        object: "os_auth",
+        method: "reauthenticate",
+        value: result.auth_details,
+        extra: result.auth_details_extra,
+      };
+      return {
+        isAuthorized,
+        telemetryEvent,
+      };
+    }
+    // We'll attempt to re-auth via Primary Password, force a log-out
+    token.checkPassword("");
+
+    // If a primary password prompt is already open, just exit early and return false.
+    // The user can re-trigger it after responding to the already open dialog.
+    if (Services.logins.uiBusy) {
+      isAuthorized = false;
+      return {
+        isAuthorized,
+        telemetryEvent,
+      };
+    }
+
+    // So there's a primary password. But since checkPassword didn't succeed, we're logged out (per nsIPK11Token.idl).
+    try {
+      // Relogin and ask for the primary password.
+      token.login(true); // 'true' means always prompt for token password. User will be prompted until
+      // clicking 'Cancel' or entering the correct password.
+    } catch (e) {
+      // An exception will be thrown if the user cancels the login prompt dialog.
+      // User is also logged out of Software Security Device.
+    }
+    isAuthorized = token.isLoggedIn();
+    telemetryEvent = {
+      object: "master_password",
+      method: "reauthenticate",
+      value: isAuthorized ? "success" : "fail",
+    };
+    return {
+      isAuthorized,
+      telemetryEvent,
+    };
+  },
+
+  /**
+   * Send a notification when stored data is changed.
+   */
+  notifyStorageChanged(changeType, data) {
+    if (this.importing) {
+      return;
+    }
+
+    let dataObject = data;
+    // Can't pass a raw JS string or array though notifyObservers(). :-(
+    if (Array.isArray(data)) {
+      dataObject = Cc["@mozilla.org/array;1"].createInstance(
+        Ci.nsIMutableArray
+      );
+      for (let i = 0; i < data.length; i++) {
+        dataObject.appendElement(data[i]);
+      }
+    } else if (typeof data == "string") {
+      dataObject = Cc["@mozilla.org/supports-string;1"].createInstance(
+        Ci.nsISupportsString
+      );
+      dataObject.data = data;
+    }
+    Services.obs.notifyObservers(
+      dataObject,
+      "passwordmgr-storage-changed",
+      changeType
+    );
+  },
+
+  isUserFacingLogin(login) {
+    return login.origin != "chrome://FirefoxAccounts"; // FXA_PWDMGR_HOST
+  },
+
+  async getAllUserFacingLogins() {
+    try {
+      let logins = await Services.logins.getAllLogins();
+      return logins.filter(this.isUserFacingLogin);
+    } catch (e) {
+      if (e.result == Cr.NS_ERROR_ABORT) {
+        // If the user cancels the MP prompt then return no logins.
+        return [];
+      }
+      throw e;
+    }
+  },
+
+  createLoginAlreadyExistsError(guid) {
+    // The GUID is stored in an nsISupportsString here because we cannot pass
+    // raw JS objects within Components.Exception due to bug 743121.
+    let guidSupportsString = Cc[
+      "@mozilla.org/supports-string;1"
+    ].createInstance(Ci.nsISupportsString);
+    guidSupportsString.data = guid;
+    return Components.Exception("This login already exists.", {
+      data: guidSupportsString,
+    });
+  },
+
+  /**
+   * Determine the <browser> that a prompt should be shown on.
+   *
+   * Some sites pop up a temporary login window, which disappears
+   * upon submission of credentials. We want to put the notification
+   * prompt in the opener window if this seems to be happening.
+   *
+   * @param {Element} browser
+   *        The <browser> that a prompt was triggered for
+   * @returns {Element} The <browser> that the prompt should be shown on,
+   *                    which could be in a different window.
+   */
+  getBrowserForPrompt(browser) {
+    let chromeWindow = browser.ownerGlobal;
+    let openerBrowsingContext = browser.browsingContext.opener;
+    let openerBrowser = openerBrowsingContext
+      ? openerBrowsingContext.top.embedderElement
+      : null;
+    if (openerBrowser) {
+      let chromeDoc = chromeWindow.document.documentElement;
+
+      // Check to see if the current window was opened with chrome
+      // disabled, and if so use the opener window. But if the window
+      // has been used to visit other pages (ie, has a history),
+      // assume it'll stick around and *don't* use the opener.
+      if (chromeDoc.getAttribute("chromehidden") && !browser.canGoBack) {
+        lazy.log.debug("Using opener window for prompt.");
+        return openerBrowser;
+      }
+    }
+
+    return browser;
+  },
+};
+
+ChromeUtils.defineLazyGetter(lazy, "log", () => {
+  let processName =
+    Services.appinfo.processType === Services.appinfo.PROCESS_TYPE_DEFAULT
+      ? "Main"
+      : "Content";
+  return LoginHelper.createLogger(`LoginHelper(${processName})`);
+});
+
+LoginHelper.init();
+
+export class OptInFeature {
+  implementation;
+  #offered;
+  #enabled;
+  #disabled;
+  #pref;
+
+  static PREF_AVAILABLE_VALUE = "available";
+  static PREF_OFFERED_VALUE = "offered";
+  static PREF_ENABLED_VALUE = "enabled";
+  static PREF_DISABLED_VALUE = "disabled";
+
+  constructor(offered, enabled, disabled, pref) {
+    this.#pref = pref;
+    this.#offered = offered;
+    this.#enabled = enabled;
+    this.#disabled = disabled;
+
+    XPCOMUtils.defineLazyPreferenceGetter(
+      this,
+      "implementationPref",
+      pref,
+      undefined,
+      (_preference, _prevValue, _newValue) => this.#updateImplementation()
+    );
+
+    this.#updateImplementation();
+  }
+
+  get #currentPrefValue() {
+    // Read pref directly instead of relying on this.implementationPref because
+    // there is an implementationPref value update lag that affects tests.
+    return Services.prefs.getStringPref(this.#pref, undefined);
+  }
+
+  get isAvailable() {
+    return [
+      OptInFeature.PREF_AVAILABLE_VALUE,
+      OptInFeature.PREF_OFFERED_VALUE,
+      OptInFeature.PREF_ENABLED_VALUE,
+      OptInFeature.PREF_DISABLED_VALUE,
+    ].includes(this.#currentPrefValue);
+  }
+
+  get isEnabled() {
+    return this.#currentPrefValue == OptInFeature.PREF_ENABLED_VALUE;
+  }
+
+  get isDisabled() {
+    return this.#currentPrefValue == OptInFeature.PREF_DISABLED_VALUE;
+  }
+
+  markAsAvailable() {
+    this.#markAs(OptInFeature.PREF_AVAILABLE_VALUE);
+  }
+
+  markAsOffered() {
+    this.#markAs(OptInFeature.PREF_OFFERED_VALUE);
+  }
+
+  markAsEnabled() {
+    this.#markAs(OptInFeature.PREF_ENABLED_VALUE);
+  }
+
+  markAsDisabled() {
+    this.#markAs(OptInFeature.PREF_DISABLED_VALUE);
+  }
+
+  #markAs(value) {
+    Services.prefs.setStringPref(this.#pref, value);
+  }
+
+  #updateImplementation() {
+    switch (this.implementationPref) {
+      case OptInFeature.PREF_ENABLED_VALUE:
+        this.implementation = new this.#enabled();
+        break;
+      case OptInFeature.PREF_AVAILABLE_VALUE:
+      case OptInFeature.PREF_OFFERED_VALUE:
+        this.implementation = new this.#offered();
+        break;
+      case OptInFeature.PREF_DISABLED_VALUE:
+      default:
+        this.implementation = new this.#disabled();
+        break;
+    }
+  }
+}
diff --git a/toolkit/components/passwordmgr/LoginInfo.sys.mjs b/toolkit/components/passwordmgr/LoginInfo.sys.mjs
new file mode 100644
index 0000000000..79ea17b1f1
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginInfo.sys.mjs
@@ -0,0 +1,144 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+});
+
+export function nsLoginInfo() {}
+
+nsLoginInfo.prototype = {
+  classID: Components.ID("{0f2f347c-1e4f-40cc-8efd-792dea70a85e}"),
+  QueryInterface: ChromeUtils.generateQI(["nsILoginInfo", "nsILoginMetaInfo"]),
+
+  //
+  // nsILoginInfo interfaces...
+  //
+
+  origin: null,
+  formActionOrigin: null,
+  httpRealm: null,
+  username: null,
+  password: null,
+  usernameField: null,
+  passwordField: null,
+  unknownFields: null,
+
+  everSynced: false,
+  syncCounter: 0,
+
+  get displayOrigin() {
+    let displayOrigin = this.origin;
+    try {
+      let uri = Services.io.newURI(this.origin);
+      // Fallback to handle file: URIs
+      displayOrigin = uri.displayHostPort || this.origin;
+    } catch (ex) {
+      // Fallback to this.origin set above in case a URI can't be contructed e.g.
+      // file://
+    }
+
+    if (this.httpRealm === null) {
+      return displayOrigin;
+    }
+
+    return `${displayOrigin} (${this.httpRealm})`;
+  },
+
+  /**
+   * @deprecated Use `origin` instead.
+   */
+  get hostname() {
+    return this.origin;
+  },
+
+  /**
+   * @deprecated Use `formActionOrigin` instead.
+   */
+  get formSubmitURL() {
+    return this.formActionOrigin;
+  },
+
+  init(
+    aOrigin,
+    aFormActionOrigin,
+    aHttpRealm,
+    aUsername,
+    aPassword,
+    aUsernameField = "",
+    aPasswordField = ""
+  ) {
+    this.origin = aOrigin;
+    this.formActionOrigin = aFormActionOrigin;
+    this.httpRealm = aHttpRealm;
+    this.username = aUsername;
+    this.password = aPassword;
+    this.usernameField = aUsernameField || "";
+    this.passwordField = aPasswordField || "";
+  },
+
+  matches(aLogin, ignorePassword) {
+    return lazy.LoginHelper.doLoginsMatch(this, aLogin, {
+      ignorePassword,
+    });
+  },
+
+  equals(aLogin) {
+    if (
+      this.origin != aLogin.origin ||
+      this.formActionOrigin != aLogin.formActionOrigin ||
+      this.httpRealm != aLogin.httpRealm ||
+      this.username != aLogin.username ||
+      this.password != aLogin.password ||
+      this.usernameField != aLogin.usernameField ||
+      this.passwordField != aLogin.passwordField
+    ) {
+      return false;
+    }
+
+    return true;
+  },
+
+  clone() {
+    let clone = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(
+      Ci.nsILoginInfo
+    );
+    clone.init(
+      this.origin,
+      this.formActionOrigin,
+      this.httpRealm,
+      this.username,
+      this.password,
+      this.usernameField,
+      this.passwordField
+    );
+
+    // Copy nsILoginMetaInfo props
+    clone.QueryInterface(Ci.nsILoginMetaInfo);
+    clone.guid = this.guid;
+    clone.timeCreated = this.timeCreated;
+    clone.timeLastUsed = this.timeLastUsed;
+    clone.timePasswordChanged = this.timePasswordChanged;
+    clone.timesUsed = this.timesUsed;
+    clone.syncCounter = this.syncCounter;
+    clone.everSynced = this.everSynced;
+
+    // Unknown fields from other clients
+    clone.unknownFields = this.unknownFields;
+
+    return clone;
+  },
+
+  //
+  // nsILoginMetaInfo interfaces...
+  //
+
+  guid: null,
+  timeCreated: null,
+  timeLastUsed: null,
+  timePasswordChanged: null,
+  timesUsed: null,
+}; // end of nsLoginInfo implementation
diff --git a/toolkit/components/passwordmgr/LoginManager.shared.mjs b/toolkit/components/passwordmgr/LoginManager.shared.mjs
new file mode 100644
index 0000000000..d50c53cbad
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginManager.shared.mjs
@@ -0,0 +1,44 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Code that we can share across Firefox Desktop, Firefox Android and Firefox iOS.
+ */
+
+class Logic {
+  static inputTypeIsCompatibleWithUsername(input) {
+    const fieldType = input.getAttribute("type")?.toLowerCase() || input.type;
+    return (
+      ["text", "email", "url", "tel", "number", "search"].includes(fieldType) ||
+      fieldType?.includes("user")
+    );
+  }
+
+  /**
+   * Test whether the element has the keyword in its attributes.
+   * The tested attributes include id, name, className, and placeholder.
+   */
+  static elementAttrsMatchRegex(element, regex) {
+    if (
+      regex.test(element.id) ||
+      regex.test(element.name) ||
+      regex.test(element.className)
+    ) {
+      return true;
+    }
+
+    const placeholder = element.getAttribute("placeholder");
+    return placeholder && regex.test(placeholder);
+  }
+
+  /**
+   * Test whether associated labels of the element have the keyword.
+   * This is a simplified rule of hasLabelMatchingRegex in NewPasswordModel.jsm
+   */
+  static hasLabelMatchingRegex(element, regex) {
+    return regex.test(element.labels?.[0]?.textContent);
+  }
+}
+
+export { Logic };
diff --git a/toolkit/components/passwordmgr/LoginManager.sys.mjs b/toolkit/components/passwordmgr/LoginManager.sys.mjs
new file mode 100644
index 0000000000..b95f3ada8b
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginManager.sys.mjs
@@ -0,0 +1,618 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const PERMISSION_SAVE_LOGINS = "login-saving";
+const MAX_DATE_MS = 8640000000000000;
+
+import { LoginManagerStorage } from "resource://passwordmgr/passwordstorage.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+});
+
+ChromeUtils.defineLazyGetter(lazy, "log", () => {
+  let logger = lazy.LoginHelper.createLogger("LoginManager");
+  return logger;
+});
+
+const MS_PER_DAY = 24 * 60 * 60 * 1000;
+
+if (Services.appinfo.processType !== Services.appinfo.PROCESS_TYPE_DEFAULT) {
+  throw new Error("LoginManager.jsm should only run in the parent process");
+}
+
+export function LoginManager() {
+  this.init();
+}
+
+LoginManager.prototype = {
+  classID: Components.ID("{cb9e0de8-3598-4ed7-857b-827f011ad5d8}"),
+  QueryInterface: ChromeUtils.generateQI([
+    "nsILoginManager",
+    "nsISupportsWeakReference",
+    "nsIInterfaceRequestor",
+  ]),
+  getInterface(aIID) {
+    if (aIID.equals(Ci.mozIStorageConnection) && this._storage) {
+      let ir = this._storage.QueryInterface(Ci.nsIInterfaceRequestor);
+      return ir.getInterface(aIID);
+    }
+
+    if (aIID.equals(Ci.nsIVariant)) {
+      // Allows unwrapping the JavaScript object for regression tests.
+      return this;
+    }
+
+    throw new Components.Exception(
+      "Interface not available",
+      Cr.NS_ERROR_NO_INTERFACE
+    );
+  },
+
+  /* ---------- private members ---------- */
+
+  _storage: null, // Storage component which contains the saved logins
+
+  /**
+   * Initialize the Login Manager. Automatically called when service
+   * is created.
+   *
+   * Note: Service created in BrowserGlue#_scheduleStartupIdleTasks()
+   */
+  init() {
+    // Cache references to current |this| in utility objects
+    this._observer._pwmgr = this;
+
+    Services.obs.addObserver(this._observer, "xpcom-shutdown");
+    Services.obs.addObserver(this._observer, "passwordmgr-storage-replace");
+
+    // Initialize storage so that asynchronous data loading can start.
+    this._initStorage();
+
+    Services.obs.addObserver(this._observer, "gather-telemetry");
+  },
+
+  _initStorage() {
+    this.initializationPromise = new Promise(resolve => {
+      this._storage = LoginManagerStorage.create(() => {
+        resolve();
+
+        lazy.log.debug(
+          "initializationPromise is resolved, updating isPrimaryPasswordSet in sharedData"
+        );
+        Services.ppmm.sharedData.set(
+          "isPrimaryPasswordSet",
+          lazy.LoginHelper.isPrimaryPasswordSet()
+        );
+      });
+    });
+  },
+
+  /* ---------- Utility objects ---------- */
+
+  /**
+   * Internal utility object, implements the nsIObserver interface.
+   * Used to receive notification for: form submission, preference changes.
+   */
+  _observer: {
+    _pwmgr: null,
+
+    QueryInterface: ChromeUtils.generateQI([
+      "nsIObserver",
+      "nsISupportsWeakReference",
+    ]),
+
+    // nsIObserver
+    observe(subject, topic, data) {
+      if (topic == "xpcom-shutdown") {
+        delete this._pwmgr._storage;
+        this._pwmgr = null;
+      } else if (topic == "passwordmgr-storage-replace") {
+        (async () => {
+          await this._pwmgr._storage.terminate();
+          this._pwmgr._initStorage();
+          await this._pwmgr.initializationPromise;
+          Services.obs.notifyObservers(
+            null,
+            "passwordmgr-storage-replace-complete"
+          );
+        })();
+      } else if (topic == "gather-telemetry") {
+        // When testing, the "data" parameter is a string containing the
+        // reference time in milliseconds for time-based statistics.
+        this._pwmgr._gatherTelemetry(
+          data ? parseInt(data) : new Date().getTime()
+        );
+      } else {
+        lazy.log.debug(`Unexpected notification: ${topic}.`);
+      }
+    },
+  },
+
+  /**
+   * Collects statistics about the current logins and settings. The telemetry
+   * histograms used here are not accumulated, but are reset each time this
+   * function is called, since it can be called multiple times in a session.
+   *
+   * This function might also not be called at all in the current session.
+   *
+   * @param referenceTimeMs
+   *        Current time used to calculate time-based statistics, expressed as
+   *        the number of milliseconds since January 1, 1970, 00:00:00 UTC.
+   *        This is set to a fake value during unit testing.
+   */
+  async _gatherTelemetry(referenceTimeMs) {
+    function clearAndGetHistogram(histogramId) {
+      let histogram = Services.telemetry.getHistogramById(histogramId);
+      histogram.clear();
+      return histogram;
+    }
+
+    clearAndGetHistogram("PWMGR_BLOCKLIST_NUM_SITES").add(
+      this.getAllDisabledHosts().length
+    );
+    clearAndGetHistogram("PWMGR_NUM_SAVED_PASSWORDS").add(
+      this.countLogins("", "", "")
+    );
+    clearAndGetHistogram("PWMGR_NUM_HTTPAUTH_PASSWORDS").add(
+      this.countLogins("", null, "")
+    );
+    Services.obs.notifyObservers(
+      null,
+      "weave:telemetry:histogram",
+      "PWMGR_BLOCKLIST_NUM_SITES"
+    );
+    Services.obs.notifyObservers(
+      null,
+      "weave:telemetry:histogram",
+      "PWMGR_NUM_SAVED_PASSWORDS"
+    );
+
+    // This is a boolean histogram, and not a flag, because we don't want to
+    // record any value if _gatherTelemetry is not called.
+    clearAndGetHistogram("PWMGR_SAVING_ENABLED").add(lazy.LoginHelper.enabled);
+    Services.obs.notifyObservers(
+      null,
+      "weave:telemetry:histogram",
+      "PWMGR_SAVING_ENABLED"
+    );
+
+    // Don't try to get logins if MP is enabled, since we don't want to show a MP prompt.
+    if (!this.isLoggedIn) {
+      return;
+    }
+
+    let logins = await this.getAllLogins();
+
+    let usernamePresentHistogram = clearAndGetHistogram(
+      "PWMGR_USERNAME_PRESENT"
+    );
+    let loginLastUsedDaysHistogram = clearAndGetHistogram(
+      "PWMGR_LOGIN_LAST_USED_DAYS"
+    );
+
+    let originCount = new Map();
+    for (let login of logins) {
+      usernamePresentHistogram.add(!!login.username);
+
+      let origin = login.origin;
+      originCount.set(origin, (originCount.get(origin) || 0) + 1);
+
+      login.QueryInterface(Ci.nsILoginMetaInfo);
+      let timeLastUsedAgeMs = referenceTimeMs - login.timeLastUsed;
+      if (timeLastUsedAgeMs > 0) {
+        loginLastUsedDaysHistogram.add(
+          Math.floor(timeLastUsedAgeMs / MS_PER_DAY)
+        );
+      }
+    }
+    Services.obs.notifyObservers(
+      null,
+      "weave:telemetry:histogram",
+      "PWMGR_LOGIN_LAST_USED_DAYS"
+    );
+
+    let passwordsCountHistogram = clearAndGetHistogram(
+      "PWMGR_NUM_PASSWORDS_PER_HOSTNAME"
+    );
+    for (let count of originCount.values()) {
+      passwordsCountHistogram.add(count);
+    }
+    Services.obs.notifyObservers(
+      null,
+      "weave:telemetry:histogram",
+      "PWMGR_NUM_PASSWORDS_PER_HOSTNAME"
+    );
+
+    Services.obs.notifyObservers(null, "passwordmgr-gather-telemetry-complete");
+  },
+
+  /**
+   * Ensures that a login isn't missing any necessary fields.
+   *
+   * @param login
+   *        The login to check.
+   */
+  _checkLogin(login) {
+    // Sanity check the login
+    if (login.origin == null || !login.origin.length) {
+      throw new Error("Can't add a login with a null or empty origin.");
+    }
+
+    // For logins w/o a username, set to "", not null.
+    if (login.username == null) {
+      throw new Error("Can't add a login with a null username.");
+    }
+
+    if (login.password == null || !login.password.length) {
+      throw new Error("Can't add a login with a null or empty password.");
+    }
+
+    // Duplicated from toolkit/components/passwordmgr/LoginHelper.sys.jms
+    // TODO: move all validations into this function.
+    //
+    // In theory these nulls should just be rolled up into the encrypted
+    // values, but nsISecretDecoderRing doesn't use nsStrings, so the
+    // nulls cause truncation. Check for them here just to avoid
+    // unexpected round-trip surprises.
+    if (login.username.includes("\0") || login.password.includes("\0")) {
+      throw new Error("login values can't contain nulls");
+    }
+
+    if (login.formActionOrigin || login.formActionOrigin == "") {
+      // We have a form submit URL. Can't have a HTTP realm.
+      if (login.httpRealm != null) {
+        throw new Error(
+          "Can't add a login with both a httpRealm and formActionOrigin."
+        );
+      }
+    } else if (login.httpRealm || login.httpRealm == "") {
+      // We have a HTTP realm. Can't have a form submit URL.
+      if (login.formActionOrigin != null) {
+        throw new Error(
+          "Can't add a login with both a httpRealm and formActionOrigin."
+        );
+      }
+    } else {
+      // Need one or the other!
+      throw new Error(
+        "Can't add a login without a httpRealm or formActionOrigin."
+      );
+    }
+
+    login.QueryInterface(Ci.nsILoginMetaInfo);
+    for (let pname of ["timeCreated", "timeLastUsed", "timePasswordChanged"]) {
+      // Invalid dates
+      if (login[pname] > MAX_DATE_MS) {
+        throw new Error("Can't add a login with invalid date properties.");
+      }
+    }
+  },
+
+  /* ---------- Primary Public interfaces ---------- */
+
+  /**
+   * @type Promise
+   * This promise is resolved when initialization is complete, and is rejected
+   * in case the asynchronous part of initialization failed.
+   */
+  initializationPromise: null,
+
+  /**
+   * Add a new login to login storage.
+   */
+  async addLoginAsync(login) {
+    this._checkLogin(login);
+
+    lazy.log.debug("Adding login");
+    const [resultLogin] = await this._storage.addLoginsAsync([login]);
+    return resultLogin;
+  },
+
+  /**
+   * Add multiple logins to login storage.
+   * TODO: rename to `addLoginsAsync` https://bugzilla.mozilla.org/show_bug.cgi?id=1832757
+   */
+  async addLogins(logins) {
+    if (logins.length === 0) {
+      return logins;
+    }
+
+    const validLogins = logins.filter(login => {
+      try {
+        this._checkLogin(login);
+        return true;
+      } catch (e) {
+        console.error(e);
+        return false;
+      }
+    });
+    lazy.log.debug("Adding logins");
+    return this._storage.addLoginsAsync(validLogins, true);
+  },
+
+  /**
+   * Remove the specified login from the stored logins.
+   */
+  removeLogin(login) {
+    lazy.log.debug(
+      "Removing login",
+      login.QueryInterface(Ci.nsILoginMetaInfo).guid
+    );
+    return this._storage.removeLogin(login);
+  },
+
+  /**
+   * Change the specified login to match the new login or new properties.
+   */
+  modifyLogin(oldLogin, newLogin) {
+    lazy.log.debug(
+      "Modifying login",
+      oldLogin.QueryInterface(Ci.nsILoginMetaInfo).guid
+    );
+    return this._storage.modifyLogin(oldLogin, newLogin);
+  },
+
+  /**
+   * Record that the password of a saved login was used (e.g. submitted or copied).
+   */
+  recordPasswordUse(
+    login,
+    privateContextWithoutExplicitConsent,
+    loginType,
+    filled
+  ) {
+    lazy.log.debug(
+      "Recording password use",
+      loginType,
+      login.QueryInterface(Ci.nsILoginMetaInfo).guid
+    );
+    if (!privateContextWithoutExplicitConsent) {
+      // don't record non-interactive use in private browsing
+      this._storage.recordPasswordUse(login);
+    }
+
+    Services.telemetry.recordEvent(
+      "pwmgr",
+      "saved_login_used",
+      loginType,
+      null,
+      {
+        filled: "" + filled,
+      }
+    );
+  },
+
+  /**
+   * Get a dump of all stored logins asynchronously. Used by the login manager UI.
+   *
+   * @return {nsILoginInfo[]} - If there are no logins, the array is empty.
+   */
+  async getAllLogins() {
+    lazy.log.debug("Getting a list of all logins asynchronously.");
+    return this._storage.getAllLogins();
+  },
+
+  /**
+   * Get a dump of all stored logins asynchronously. Used by the login detection service.
+   */
+  getAllLoginsWithCallback(aCallback) {
+    lazy.log.debug("Searching a list of all logins asynchronously.");
+    this._storage.getAllLogins().then(logins => {
+      aCallback.onSearchComplete(logins);
+    });
+  },
+
+  /**
+   * Remove all user facing stored logins.
+   *
+   * This will not remove the FxA Sync key, which is stored with the rest of a user's logins.
+   */
+  removeAllUserFacingLogins() {
+    lazy.log.debug("Removing all user facing logins.");
+    this._storage.removeAllUserFacingLogins();
+  },
+
+  /**
+   * Remove all logins from data store, including the FxA Sync key.
+   *
+   * NOTE: You probably want `removeAllUserFacingLogins()` instead of this function.
+   * This function will remove the FxA Sync key, which will break syncing of saved user data
+   * e.g. bookmarks, history, open tabs, logins and passwords, add-ons, and options
+   */
+  removeAllLogins() {
+    lazy.log.debug("Removing all logins from local store, including FxA key.");
+    this._storage.removeAllLogins();
+  },
+
+  /**
+   * Get a list of all origins for which logins are disabled.
+   *
+   * @param {Number} count - only needed for XPCOM.
+   *
+   * @return {String[]} of disabled origins. If there are no disabled origins,
+   *                    the array is empty.
+   */
+  getAllDisabledHosts() {
+    lazy.log.debug("Getting a list of all disabled origins.");
+
+    let disabledHosts = [];
+    for (let perm of Services.perms.all) {
+      if (
+        perm.type == PERMISSION_SAVE_LOGINS &&
+        perm.capability == Services.perms.DENY_ACTION
+      ) {
+        disabledHosts.push(perm.principal.URI.displayPrePath);
+      }
+    }
+
+    lazy.log.debug(`Returning ${disabledHosts.length} disabled hosts.`);
+    return disabledHosts;
+  },
+
+  /**
+   * Search for the known logins for entries matching the specified criteria.
+   */
+  findLogins(origin, formActionOrigin, httpRealm) {
+    lazy.log.debug(
+      "Searching for logins matching origin:",
+      origin,
+      "formActionOrigin:",
+      formActionOrigin,
+      "httpRealm:",
+      httpRealm
+    );
+
+    return this._storage.findLogins(origin, formActionOrigin, httpRealm);
+  },
+
+  async searchLoginsAsync(matchData) {
+    lazy.log.debug(
+      `Searching for matching logins for origin: ${matchData.origin}`
+    );
+
+    if (!matchData.origin) {
+      throw new Error("searchLoginsAsync: An `origin` is required");
+    }
+
+    return this._storage.searchLoginsAsync(matchData);
+  },
+
+  /**
+   * @return {nsILoginInfo[]} which are decrypted.
+   */
+  searchLogins(matchData) {
+    lazy.log.debug(
+      `Searching for matching logins for origin: ${matchData.origin}`
+    );
+
+    matchData.QueryInterface(Ci.nsIPropertyBag2);
+    if (!matchData.hasKey("guid")) {
+      if (!matchData.hasKey("origin")) {
+        lazy.log.warn("An `origin` field is recommended.");
+      }
+    }
+
+    return this._storage.searchLogins(matchData);
+  },
+
+  /**
+   * Search for the known logins for entries matching the specified criteria,
+   * returns only the count.
+   */
+  countLogins(origin, formActionOrigin, httpRealm) {
+    const loginsCount = this._storage.countLogins(
+      origin,
+      formActionOrigin,
+      httpRealm
+    );
+
+    lazy.log.debug(
+      `Found ${loginsCount} matching origin: ${origin}, formActionOrigin: ${formActionOrigin} and realm: ${httpRealm}`
+    );
+
+    return loginsCount;
+  },
+
+  /* Sync metadata functions */
+  async getSyncID() {
+    return this._storage.getSyncID();
+  },
+
+  async setSyncID(id) {
+    await this._storage.setSyncID(id);
+  },
+
+  async getLastSync() {
+    return this._storage.getLastSync();
+  },
+
+  async setLastSync(timestamp) {
+    await this._storage.setLastSync(timestamp);
+  },
+
+  async ensureCurrentSyncID(newSyncID) {
+    let existingSyncID = await this.getSyncID();
+    if (existingSyncID == newSyncID) {
+      return existingSyncID;
+    }
+    lazy.log.debug(
+      `ensureCurrentSyncID: newSyncID: ${newSyncID} existingSyncID: ${existingSyncID}`
+    );
+
+    await this.setSyncID(newSyncID);
+    await this.setLastSync(0);
+    return newSyncID;
+  },
+
+  get uiBusy() {
+    return this._storage.uiBusy;
+  },
+
+  get isLoggedIn() {
+    return this._storage.isLoggedIn;
+  },
+
+  /**
+   * Check to see if user has disabled saving logins for the origin.
+   */
+  getLoginSavingEnabled(origin) {
+    lazy.log.debug(`Checking if logins to ${origin} can be saved.`);
+    if (!lazy.LoginHelper.enabled) {
+      return false;
+    }
+
+    try {
+      let uri = Services.io.newURI(origin);
+      let principal = Services.scriptSecurityManager.createContentPrincipal(
+        uri,
+        {}
+      );
+      return (
+        Services.perms.testPermissionFromPrincipal(
+          principal,
+          PERMISSION_SAVE_LOGINS
+        ) != Services.perms.DENY_ACTION
+      );
+    } catch (ex) {
+      if (!origin.startsWith("chrome:")) {
+        console.error(ex);
+      }
+      return false;
+    }
+  },
+
+  /**
+   * Enable or disable storing logins for the specified origin.
+   */
+  setLoginSavingEnabled(origin, enabled) {
+    // Throws if there are bogus values.
+    lazy.LoginHelper.checkOriginValue(origin);
+
+    let uri = Services.io.newURI(origin);
+    let principal = Services.scriptSecurityManager.createContentPrincipal(
+      uri,
+      {}
+    );
+    if (enabled) {
+      Services.perms.removeFromPrincipal(principal, PERMISSION_SAVE_LOGINS);
+    } else {
+      Services.perms.addFromPrincipal(
+        principal,
+        PERMISSION_SAVE_LOGINS,
+        Services.perms.DENY_ACTION
+      );
+    }
+
+    lazy.log.debug(
+      `Enabling login saving for ${origin} now enabled? ${enabled}.`
+    );
+    lazy.LoginHelper.notifyStorageChanged(
+      enabled ? "hostSavingEnabled" : "hostSavingDisabled",
+      origin
+    );
+  },
+}; // end of LoginManager implementation
diff --git a/toolkit/components/passwordmgr/LoginManagerAuthPrompter.sys.mjs b/toolkit/components/passwordmgr/LoginManagerAuthPrompter.sys.mjs
new file mode 100644
index 0000000000..8c39cf09b9
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginManagerAuthPrompter.sys.mjs
@@ -0,0 +1,1124 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import { PrivateBrowsingUtils } from "resource://gre/modules/PrivateBrowsingUtils.sys.mjs";
+import { PromptUtils } from "resource://gre/modules/PromptUtils.sys.mjs";
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+
+const lazy = {};
+
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "gPrompterService",
+  "@mozilla.org/login-manager/prompter;1",
+  Ci.nsILoginManagerPrompter
+);
+
+/* eslint-disable block-scoped-var, no-var */
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+});
+
+const LoginInfo = Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  "nsILoginInfo",
+  "init"
+);
+
+/**
+ * A helper module to prevent modal auth prompt abuse.
+ */
+const PromptAbuseHelper = {
+  getBaseDomainOrFallback(hostname) {
+    try {
+      return Services.eTLD.getBaseDomainFromHost(hostname);
+    } catch (e) {
+      return hostname;
+    }
+  },
+
+  incrementPromptAbuseCounter(baseDomain, browser) {
+    if (!browser) {
+      return;
+    }
+
+    if (!browser.authPromptAbuseCounter) {
+      browser.authPromptAbuseCounter = {};
+    }
+
+    if (!browser.authPromptAbuseCounter[baseDomain]) {
+      browser.authPromptAbuseCounter[baseDomain] = 0;
+    }
+
+    browser.authPromptAbuseCounter[baseDomain] += 1;
+  },
+
+  resetPromptAbuseCounter(baseDomain, browser) {
+    if (!browser || !browser.authPromptAbuseCounter) {
+      return;
+    }
+
+    browser.authPromptAbuseCounter[baseDomain] = 0;
+  },
+
+  hasReachedAbuseLimit(baseDomain, browser) {
+    if (!browser || !browser.authPromptAbuseCounter) {
+      return false;
+    }
+
+    let abuseCounter = browser.authPromptAbuseCounter[baseDomain];
+    // Allow for setting -1 to turn the feature off.
+    if (this.abuseLimit < 0) {
+      return false;
+    }
+    return !!abuseCounter && abuseCounter >= this.abuseLimit;
+  },
+};
+
+XPCOMUtils.defineLazyPreferenceGetter(
+  PromptAbuseHelper,
+  "abuseLimit",
+  "prompts.authentication_dialog_abuse_limit"
+);
+
+/**
+ * Implements nsIPromptFactory
+ *
+ * Invoked by [toolkit/components/prompts/src/Prompter.jsm]
+ */
+export function LoginManagerAuthPromptFactory() {
+  Services.obs.addObserver(this, "passwordmgr-crypto-login", true);
+}
+
+LoginManagerAuthPromptFactory.prototype = {
+  classID: Components.ID("{749e62f4-60ae-4569-a8a2-de78b649660e}"),
+  QueryInterface: ChromeUtils.generateQI([
+    "nsIPromptFactory",
+    "nsIObserver",
+    "nsISupportsWeakReference",
+  ]),
+
+  // Tracks pending auth prompts per top level browser and hash key.
+  // browser -> hashkey -> prompt
+  // This enables us to consolidate auth prompts with the same browser and
+  // hashkey (level, origin, realm).
+  _pendingPrompts: new WeakMap(),
+  _pendingSavePrompts: new WeakMap(),
+  // We use a separate bucket for when we don't have a browser.
+  // _noBrowser -> hashkey -> prompt
+  _noBrowser: {},
+  // Promise used to defer prompts if the password manager isn't ready when
+  // they're called.
+  _uiBusyPromise: null,
+  _uiBusyResolve: null,
+
+  observe(subject, topic, data) {
+    this.log(`Observed topic: ${topic}.`);
+    if (topic == "passwordmgr-crypto-login") {
+      // Show the deferred prompters.
+      this._uiBusyResolve?.();
+    }
+  },
+
+  getPrompt(aWindow, aIID) {
+    var prompt = new LoginManagerAuthPrompter().QueryInterface(aIID);
+    prompt.init(aWindow, this);
+    return prompt;
+  },
+
+  getPendingPrompt(browser, hashKey) {
+    // If there is already a matching auth prompt which has no browser
+    // associated we can reuse it. This way we avoid showing tab level prompts
+    // when there is already a pending window prompt.
+    let pendingNoBrowserPrompt = this._pendingPrompts
+      .get(this._noBrowser)
+      ?.get(hashKey);
+    if (pendingNoBrowserPrompt) {
+      return pendingNoBrowserPrompt;
+    }
+    return this._pendingPrompts.get(browser)?.get(hashKey);
+  },
+
+  _dismissPendingSavePrompt(browser) {
+    this._pendingSavePrompts.get(browser)?.dismiss();
+    this._pendingSavePrompts.delete(browser);
+  },
+
+  _setPendingSavePrompt(browser, prompt) {
+    this._pendingSavePrompts.set(browser, prompt);
+  },
+
+  _setPendingPrompt(prompt, hashKey) {
+    let browser = prompt.prompter.browser || this._noBrowser;
+    let hashToPrompt = this._pendingPrompts.get(browser);
+    if (!hashToPrompt) {
+      hashToPrompt = new Map();
+      this._pendingPrompts.set(browser, hashToPrompt);
+    }
+    hashToPrompt.set(hashKey, prompt);
+  },
+
+  _removePendingPrompt(prompt, hashKey) {
+    let browser = prompt.prompter.browser || this._noBrowser;
+    let hashToPrompt = this._pendingPrompts.get(browser);
+    if (!hashToPrompt) {
+      return;
+    }
+    hashToPrompt.delete(hashKey);
+    if (!hashToPrompt.size) {
+      this._pendingPrompts.delete(browser);
+    }
+  },
+
+  async _waitForLoginsUI(prompt) {
+    await this._uiBusyPromise;
+
+    let [origin, httpRealm] = prompt.prompter._getAuthTarget(
+      prompt.channel,
+      prompt.authInfo
+    );
+
+    // No UI to wait for.
+    if (!Services.logins.uiBusy) {
+      return;
+    }
+
+    let hasLogins = Services.logins.countLogins(origin, null, httpRealm) > 0;
+    if (
+      !hasLogins &&
+      lazy.LoginHelper.schemeUpgrades &&
+      origin.startsWith("https://")
+    ) {
+      let httpOrigin = origin.replace(/^https:\/\//, "http://");
+      hasLogins = Services.logins.countLogins(httpOrigin, null, httpRealm) > 0;
+    }
+    // We don't depend on saved logins.
+    if (!hasLogins) {
+      return;
+    }
+
+    this.log("Waiting for primary password UI.");
+
+    this._uiBusyPromise = new Promise(resolve => {
+      this._uiBusyResolve = resolve;
+    });
+    await this._uiBusyPromise;
+  },
+
+  async _doAsyncPrompt(prompt, hashKey) {
+    this._setPendingPrompt(prompt, hashKey);
+
+    // UI might be busy due to the primary password dialog. Wait for it to close.
+    await this._waitForLoginsUI(prompt);
+
+    let ok = false;
+    let promptAborted = false;
+    try {
+      this.log(`Performing the prompt for ${hashKey}.`);
+      ok = await prompt.prompter.promptAuthInternal(
+        prompt.channel,
+        prompt.level,
+        prompt.authInfo
+      );
+    } catch (e) {
+      if (
+        e instanceof Components.Exception &&
+        e.result == Cr.NS_ERROR_NOT_AVAILABLE
+      ) {
+        this.log("Bypassed, UI is not available in this context.");
+        // Prompts throw NS_ERROR_NOT_AVAILABLE if they're aborted.
+        promptAborted = true;
+      } else {
+        console.error("LoginManagerAuthPrompter: _doAsyncPrompt", e);
+      }
+    }
+
+    this._removePendingPrompt(prompt, hashKey);
+
+    // Handle callbacks
+    for (var consumer of prompt.consumers) {
+      if (!consumer.callback) {
+        // Not having a callback means that consumer didn't provide it
+        // or canceled the notification
+        continue;
+      }
+
+      this.log(`Calling back to callback: ${consumer.callback} ok: ${ok}.`);
+      try {
+        if (ok) {
+          consumer.callback.onAuthAvailable(consumer.context, prompt.authInfo);
+        } else {
+          consumer.callback.onAuthCancelled(consumer.context, !promptAborted);
+        }
+      } catch (e) {
+        /* Throw away exceptions caused by callback */
+      }
+    }
+  },
+}; // end of LoginManagerAuthPromptFactory implementation
+
+ChromeUtils.defineLazyGetter(
+  LoginManagerAuthPromptFactory.prototype,
+  "log",
+  () => {
+    let logger = lazy.LoginHelper.createLogger("LoginManagerAuthPromptFactory");
+    return logger.log.bind(logger);
+  }
+);
+
+/* ==================== LoginManagerAuthPrompter ==================== */
+
+/**
+ * Implements interfaces for prompting the user to enter/save/change auth info.
+ *
+ * nsIAuthPrompt: Used by SeaMonkey, Thunderbird, but not Firefox.
+ *
+ * Note this implementation no longer provides `nsIAuthPrompt.promptPassword()`
+ * and `nsIAuthPrompt.promptUsernameAndPassword()`. Use their async
+ * counterparts `asyncPromptPassword` and `asyncPromptUsernameAndPassword`
+ * instead.
+ *
+ * nsIAuthPrompt2: Is invoked by a channel for protocol-based authentication
+ * (eg HTTP Authenticate, FTP login).
+ *
+ * nsILoginManagerAuthPrompter: Used by consumers to indicate which tab/window a
+ * prompt should appear on.
+ */
+export function LoginManagerAuthPrompter() {}
+
+LoginManagerAuthPrompter.prototype = {
+  classID: Components.ID("{8aa66d77-1bbb-45a6-991e-b8f47751c291}"),
+  QueryInterface: ChromeUtils.generateQI([
+    "nsIAuthPrompt",
+    "nsIAuthPrompt2",
+    "nsILoginManagerAuthPrompter",
+  ]),
+
+  _factory: null,
+  _chromeWindow: null,
+  _browser: null,
+
+  __strBundle: null, // String bundle for L10N
+  get _strBundle() {
+    if (!this.__strBundle) {
+      this.__strBundle = Services.strings.createBundle(
+        "chrome://passwordmgr/locale/passwordmgr.properties"
+      );
+      if (!this.__strBundle) {
+        throw new Error("String bundle for Login Manager not present!");
+      }
+    }
+
+    return this.__strBundle;
+  },
+
+  __ellipsis: null,
+  get _ellipsis() {
+    if (!this.__ellipsis) {
+      this.__ellipsis = "\u2026";
+      try {
+        this.__ellipsis = Services.prefs.getComplexValue(
+          "intl.ellipsis",
+          Ci.nsIPrefLocalizedString
+        ).data;
+      } catch (e) {}
+    }
+    return this.__ellipsis;
+  },
+
+  // Whether we are in private browsing mode
+  get _inPrivateBrowsing() {
+    if (this._chromeWindow) {
+      return PrivateBrowsingUtils.isWindowPrivate(this._chromeWindow);
+    }
+    // If we don't that we're in private browsing mode if the caller did
+    // not provide a window.  The callers which really care about this
+    // will indeed pass down a window to us, and for those who don't,
+    // we can just assume that we don't want to save the entered login
+    // information.
+    this.log("We have no chromeWindow so assume we're in a private context.");
+    return true;
+  },
+
+  get _allowRememberLogin() {
+    if (!this._inPrivateBrowsing) {
+      return true;
+    }
+    return lazy.LoginHelper.privateBrowsingCaptureEnabled;
+  },
+
+  /* ---------- nsIAuthPrompt prompts ---------- */
+
+  /**
+   * Wrapper around the prompt service prompt. Saving random fields here
+   * doesn't really make sense and therefore isn't implemented.
+   */
+  prompt(
+    aDialogTitle,
+    aText,
+    aPasswordRealm,
+    aSavePassword,
+    aDefaultText,
+    aResult
+  ) {
+    if (aSavePassword != Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER) {
+      throw new Components.Exception(
+        "prompt only supports SAVE_PASSWORD_NEVER",
+        Cr.NS_ERROR_NOT_IMPLEMENTED
+      );
+    }
+
+    if (aDefaultText) {
+      aResult.value = aDefaultText;
+    }
+
+    return Services.prompt.prompt(
+      this._chromeWindow,
+      aDialogTitle,
+      aText,
+      aResult,
+      null,
+      {}
+    );
+  },
+
+  /**
+   * Looks up a username and password in the database. Will prompt the user
+   * with a dialog, even if a username and password are found.
+   */
+  async asyncPromptUsernameAndPassword(
+    aDialogTitle,
+    aText,
+    aPasswordRealm,
+    aSavePassword,
+    aUsername,
+    aPassword
+  ) {
+    if (aSavePassword == Ci.nsIAuthPrompt.SAVE_PASSWORD_FOR_SESSION) {
+      throw new Components.Exception(
+        "asyncPromptUsernameAndPassword doesn't support SAVE_PASSWORD_FOR_SESSION",
+        Cr.NS_ERROR_NOT_IMPLEMENTED
+      );
+    }
+
+    let foundLogins = null;
+    let canRememberLogin = false;
+    var selectedLogin = null;
+    var [origin, realm] = this._getRealmInfo(aPasswordRealm);
+
+    // If origin is null, we can't save this login.
+    if (origin) {
+      if (this._allowRememberLogin) {
+        canRememberLogin =
+          aSavePassword == Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY &&
+          Services.logins.getLoginSavingEnabled(origin);
+      }
+
+      // Look for existing logins.
+      // We don't use searchLoginsAsync here and in asyncPromptPassword
+      // because of bug 1848682
+      let matchData = lazy.LoginHelper.newPropertyBag({
+        origin,
+        httpRealm: realm,
+      });
+      foundLogins = Services.logins.searchLogins(matchData);
+
+      // XXX Like the original code, we can't deal with multiple
+      // account selection. (bug 227632)
+      if (foundLogins.length) {
+        selectedLogin = foundLogins[0];
+
+        // If the caller provided a username, try to use it. If they
+        // provided only a password, this will try to find a password-only
+        // login (or return null if none exists).
+        if (aUsername.value) {
+          selectedLogin = this._repickSelectedLogin(
+            foundLogins,
+            aUsername.value
+          );
+        }
+
+        if (selectedLogin) {
+          aUsername.value = selectedLogin.username;
+          // If the caller provided a password, prefer it.
+          if (!aPassword.value) {
+            aPassword.value = selectedLogin.password;
+          }
+        }
+      }
+    }
+
+    let autofilled = !!aPassword.value;
+    var ok = Services.prompt.promptUsernameAndPassword(
+      this._chromeWindow,
+      aDialogTitle,
+      aText,
+      aUsername,
+      aPassword
+    );
+
+    if (!ok || !canRememberLogin) {
+      return ok;
+    }
+
+    if (!aPassword.value) {
+      this.log("No password entered, so won't offer to save.");
+      return ok;
+    }
+
+    // XXX We can't prompt with multiple logins yet (bug 227632), so
+    // the entered login might correspond to an existing login
+    // other than the one we originally selected.
+    selectedLogin = this._repickSelectedLogin(foundLogins, aUsername.value);
+
+    // If we didn't find an existing login, or if the username
+    // changed, save as a new login.
+    let newLogin = new LoginInfo(
+      origin,
+      null,
+      realm,
+      aUsername.value,
+      aPassword.value
+    );
+    if (!selectedLogin) {
+      // add as new
+      this.log(`New login seen for: ${realm}.`);
+      await Services.logins.addLoginAsync(newLogin);
+    } else if (aPassword.value != selectedLogin.password) {
+      // update password
+      this.log(`Updating password for ${realm}.`);
+      this._updateLogin(selectedLogin, newLogin);
+    } else {
+      this.log("Login unchanged, no further action needed.");
+      Services.logins.recordPasswordUse(
+        selectedLogin,
+        this._inPrivateBrowsing,
+        "prompt_login",
+        autofilled
+      );
+    }
+
+    return ok;
+  },
+
+  /**
+   * If a password is found in the database for the password realm, it is
+   * returned straight away without displaying a dialog.
+   *
+   * If a password is not found in the database, the user will be prompted
+   * with a dialog with a text field and ok/cancel buttons. If the user
+   * allows it, then the password will be saved in the database.
+   */
+  async asyncPromptPassword(
+    aDialogTitle,
+    aText,
+    aPasswordRealm,
+    aSavePassword,
+    aPassword
+  ) {
+    if (aSavePassword == Ci.nsIAuthPrompt.SAVE_PASSWORD_FOR_SESSION) {
+      throw new Components.Exception(
+        "promptPassword doesn't support SAVE_PASSWORD_FOR_SESSION",
+        Cr.NS_ERROR_NOT_IMPLEMENTED
+      );
+    }
+
+    var [origin, realm, username] = this._getRealmInfo(aPasswordRealm);
+
+    username = decodeURIComponent(username);
+
+    let canRememberLogin = false;
+    // If origin is null, we can't save this login.
+    if (origin && !this._inPrivateBrowsing) {
+      canRememberLogin =
+        aSavePassword == Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY &&
+        Services.logins.getLoginSavingEnabled(origin);
+      if (!aPassword.value) {
+        // Look for existing logins.
+        let matchData = lazy.LoginHelper.newPropertyBag({
+          origin,
+          httpRealm: realm,
+        });
+        let foundLogins = Services.logins.searchLogins(matchData);
+
+        // XXX Like the original code, we can't deal with multiple
+        // account selection (bug 227632). We can deal with finding the
+        // account based on the supplied username - but in this case we'll
+        // just return the first match.
+        for (var i = 0; i < foundLogins.length; ++i) {
+          if (foundLogins[i].username == username) {
+            aPassword.value = foundLogins[i].password;
+            // wallet returned straight away, so this mimics that code
+            return true;
+          }
+        }
+      }
+    }
+
+    var ok = Services.prompt.promptPassword(
+      this._chromeWindow,
+      aDialogTitle,
+      aText,
+      aPassword
+    );
+
+    if (ok && canRememberLogin && aPassword.value) {
+      let newLogin = new LoginInfo(
+        origin,
+        null,
+        realm,
+        username,
+        aPassword.value
+      );
+
+      this.log(`New login seen for ${realm}.`);
+
+      await Services.logins.addLoginAsync(newLogin);
+    }
+
+    return ok;
+  },
+
+  /* ---------- nsIAuthPrompt helpers ---------- */
+
+  /**
+   * Given aRealmString, such as "http://user@example.com/foo", returns an
+   * array of:
+   *   - the formatted origin
+   *   - the realm (origin + path)
+   *   - the username, if present
+   *
+   * If aRealmString is in the format produced by NS_GetAuthKey for HTTP[S]
+   * channels, e.g. "example.com:80 (httprealm)", null is returned for all
+   * arguments to let callers know the login can't be saved because we don't
+   * know whether it's http or https.
+   */
+  _getRealmInfo(aRealmString) {
+    var httpRealm = /^.+ \(.+\)$/;
+    if (httpRealm.test(aRealmString)) {
+      return [null, null, null];
+    }
+
+    var uri = Services.io.newURI(aRealmString);
+    var pathname = "";
+
+    if (uri.pathQueryRef != "/") {
+      pathname = uri.pathQueryRef;
+    }
+
+    var formattedOrigin = this._getFormattedOrigin(uri);
+
+    return [formattedOrigin, formattedOrigin + pathname, uri.username];
+  },
+
+  async promptAuthInternal(aChannel, aLevel, aAuthInfo) {
+    var selectedLogin = null;
+    var epicfail = false;
+    var canAutologin = false;
+    var foundLogins;
+    let autofilled = false;
+
+    try {
+      // If the user submits a login but it fails, we need to remove the
+      // notification prompt that was displayed. Conveniently, the user will
+      // be prompted for authentication again, which brings us here.
+      this._factory._dismissPendingSavePrompt(this._browser);
+
+      var [origin, httpRealm] = this._getAuthTarget(aChannel, aAuthInfo);
+
+      // Looks for existing logins to prefill the prompt with.
+      foundLogins = await Services.logins.searchLoginsAsync({
+        origin,
+        httpRealm,
+        schemeUpgrades: lazy.LoginHelper.schemeUpgrades,
+      });
+      this.log(`Found ${foundLogins.length} matching logins.`);
+      let resolveBy = ["scheme", "timePasswordChanged"];
+      foundLogins = lazy.LoginHelper.dedupeLogins(
+        foundLogins,
+        ["username"],
+        resolveBy,
+        origin
+      );
+      this.log(`${foundLogins.length} matching logins remain after deduping.`);
+
+      // XXX Can't select from multiple accounts yet. (bug 227632)
+      if (foundLogins.length) {
+        selectedLogin = foundLogins[0];
+        this._SetAuthInfo(
+          aAuthInfo,
+          selectedLogin.username,
+          selectedLogin.password
+        );
+        autofilled = true;
+
+        // Allow automatic proxy login
+        if (
+          aAuthInfo.flags & Ci.nsIAuthInformation.AUTH_PROXY &&
+          !(aAuthInfo.flags & Ci.nsIAuthInformation.PREVIOUS_FAILED) &&
+          Services.prefs.getBoolPref("signon.autologin.proxy") &&
+          !PrivateBrowsingUtils.permanentPrivateBrowsing
+        ) {
+          this.log("Autologin enabled, skipping auth prompt.");
+          canAutologin = true;
+        }
+      }
+
+      var canRememberLogin = Services.logins.getLoginSavingEnabled(origin);
+      if (!this._allowRememberLogin) {
+        canRememberLogin = false;
+      }
+    } catch (e) {
+      // Ignore any errors and display the prompt anyway.
+      epicfail = true;
+      console.error("LoginManagerAuthPrompter: Epic fail in promptAuth:", e);
+    }
+
+    var ok = canAutologin;
+    let browser = this._browser;
+    let baseDomain;
+
+    // We might not have a browser or browser.currentURI.host could fail
+    // (e.g. on about:blank). Fall back to the subresource hostname in that case.
+    try {
+      let topLevelHost = browser.currentURI.host;
+      baseDomain = PromptAbuseHelper.getBaseDomainOrFallback(topLevelHost);
+    } catch (e) {
+      baseDomain = PromptAbuseHelper.getBaseDomainOrFallback(origin);
+    }
+
+    if (!ok) {
+      if (PromptAbuseHelper.hasReachedAbuseLimit(baseDomain, browser)) {
+        this.log("Blocking auth dialog, due to exceeding dialog bloat limit.");
+        return false;
+      }
+
+      // Set up a counter for ensuring that the basic auth prompt can not
+      // be abused for DOS-style attacks. With this counter, each eTLD+1
+      // per browser will get a limited number of times a user can
+      // cancel the prompt until we stop showing it.
+      PromptAbuseHelper.incrementPromptAbuseCounter(baseDomain, browser);
+
+      if (this._chromeWindow) {
+        PromptUtils.fireDialogEvent(
+          this._chromeWindow,
+          "DOMWillOpenModalDialog",
+          this._browser
+        );
+      }
+
+      ok = await Services.prompt.asyncPromptAuth(
+        this._browser?.browsingContext,
+        LoginManagerAuthPrompter.promptAuthModalType,
+        aChannel,
+        aLevel,
+        aAuthInfo
+      );
+    }
+
+    let [username, password] = this._GetAuthInfo(aAuthInfo);
+
+    // Reset the counter state if the user replied to a prompt and actually
+    // tried to login (vs. simply clicking any button to get out).
+    if (ok && (username || password)) {
+      PromptAbuseHelper.resetPromptAbuseCounter(baseDomain, browser);
+    }
+
+    if (!ok || !canRememberLogin || epicfail) {
+      return ok;
+    }
+
+    try {
+      if (!password) {
+        this.log("No password entered, so won't offer to save.");
+        return ok;
+      }
+
+      // XXX We can't prompt with multiple logins yet (bug 227632), so
+      // the entered login might correspond to an existing login
+      // other than the one we originally selected.
+      selectedLogin = this._repickSelectedLogin(foundLogins, username);
+
+      // If we didn't find an existing login, or if the username
+      // changed, save as a new login.
+      let newLogin = new LoginInfo(origin, null, httpRealm, username, password);
+      if (!selectedLogin) {
+        this.log(`New login seen for origin: ${origin}.`);
+
+        let promptBrowser = lazy.LoginHelper.getBrowserForPrompt(browser);
+        let savePrompt = lazy.gPrompterService.promptToSavePassword(
+          promptBrowser,
+          newLogin
+        );
+        this._factory._setPendingSavePrompt(promptBrowser, savePrompt);
+      } else if (password != selectedLogin.password) {
+        this.log(`Updating password for origin: ${origin}.`);
+
+        let promptBrowser = lazy.LoginHelper.getBrowserForPrompt(browser);
+        let savePrompt = lazy.gPrompterService.promptToChangePassword(
+          promptBrowser,
+          selectedLogin,
+          newLogin
+        );
+        this._factory._setPendingSavePrompt(promptBrowser, savePrompt);
+      } else {
+        this.log("Login unchanged, no further action needed.");
+        Services.logins.recordPasswordUse(
+          selectedLogin,
+          this._inPrivateBrowsing,
+          "auth_login",
+          autofilled
+        );
+      }
+    } catch (e) {
+      console.error("LoginManagerAuthPrompter: Fail2 in promptAuth:", e);
+    }
+
+    return ok;
+  },
+
+  /* ---------- nsIAuthPrompt2 prompts ---------- */
+
+  /**
+   * Implementation of nsIAuthPrompt2.
+   *
+   * @param {nsIChannel} aChannel
+   * @param {int}        aLevel
+   * @param {nsIAuthInformation} aAuthInfo
+   */
+  promptAuth(aChannel, aLevel, aAuthInfo) {
+    let closed = false;
+    let result = false;
+    this.promptAuthInternal(aChannel, aLevel, aAuthInfo)
+      .then(ok => (result = ok))
+      .finally(() => (closed = true));
+    Services.tm.spinEventLoopUntilOrQuit(
+      "LoginManagerAuthPrompter.jsm:promptAuth",
+      () => closed
+    );
+    return result;
+  },
+
+  asyncPromptAuth(aChannel, aCallback, aContext, aLevel, aAuthInfo) {
+    var cancelable = null;
+
+    try {
+      // If the user submits a login but it fails, we need to remove the
+      // notification prompt that was displayed. Conveniently, the user will
+      // be prompted for authentication again, which brings us here.
+      this._factory._dismissPendingSavePrompt(this._browser);
+
+      cancelable = this._newAsyncPromptConsumer(aCallback, aContext);
+
+      let [origin, httpRealm] = this._getAuthTarget(aChannel, aAuthInfo);
+
+      let hashKey = aLevel + "|" + origin + "|" + httpRealm;
+      let pendingPrompt = this._factory.getPendingPrompt(
+        this._browser,
+        hashKey
+      );
+      if (pendingPrompt) {
+        this.log(
+          `Prompt bound to an existing one in the queue, callback: ${aCallback}.`
+        );
+        pendingPrompt.consumers.push(cancelable);
+        return cancelable;
+      }
+
+      this.log(`Adding new async prompt, callback: ${aCallback}.`);
+      let asyncPrompt = {
+        consumers: [cancelable],
+        channel: aChannel,
+        authInfo: aAuthInfo,
+        level: aLevel,
+        prompter: this,
+      };
+
+      this._factory._doAsyncPrompt(asyncPrompt, hashKey);
+    } catch (e) {
+      console.error("LoginManagerAuthPrompter: asyncPromptAuth:", e);
+      console.error("Falling back to promptAuth");
+      // Fail the prompt operation to let the consumer fall back
+      // to synchronous promptAuth method
+      throw e;
+    }
+
+    return cancelable;
+  },
+
+  /* ---------- nsILoginManagerAuthPrompter prompts ---------- */
+
+  init(aWindow = null, aFactory = null) {
+    if (!aWindow) {
+      // There may be no applicable window e.g. in a Sandbox or JSM.
+      this._chromeWindow = null;
+      this._browser = null;
+    } else if (aWindow.isChromeWindow) {
+      this._chromeWindow = aWindow;
+      // needs to be set explicitly using setBrowser
+      this._browser = null;
+    } else {
+      let { win, browser } = this._getChromeWindow(aWindow);
+      this._chromeWindow = win;
+      this._browser = browser;
+    }
+    this._factory = aFactory || null;
+  },
+
+  set browser(aBrowser) {
+    this._browser = aBrowser;
+  },
+
+  get browser() {
+    return this._browser;
+  },
+
+  /* ---------- Internal Methods ---------- */
+
+  _updateLogin(login, aNewLogin) {
+    var now = Date.now();
+    var propBag = Cc["@mozilla.org/hash-property-bag;1"].createInstance(
+      Ci.nsIWritablePropertyBag
+    );
+    propBag.setProperty("formActionOrigin", aNewLogin.formActionOrigin);
+    propBag.setProperty("origin", aNewLogin.origin);
+    propBag.setProperty("password", aNewLogin.password);
+    propBag.setProperty("username", aNewLogin.username);
+    // Explicitly set the password change time here (even though it would
+    // be changed automatically), to ensure that it's exactly the same
+    // value as timeLastUsed.
+    propBag.setProperty("timePasswordChanged", now);
+    propBag.setProperty("timeLastUsed", now);
+    propBag.setProperty("timesUsedIncrement", 1);
+    // Note that we don't call `recordPasswordUse` so we won't potentially record
+    // both a use and a save/update. See bug 1640096.
+    Services.logins.modifyLogin(login, propBag);
+  },
+
+  /**
+   * Given a content DOM window, returns the chrome window and browser it's in.
+   */
+  _getChromeWindow(aWindow) {
+    let browser = aWindow.docShell.chromeEventHandler;
+    if (!browser) {
+      return null;
+    }
+
+    let chromeWin = browser.ownerGlobal;
+    if (!chromeWin) {
+      return null;
+    }
+
+    return { win: chromeWin, browser };
+  },
+
+  /**
+   * The user might enter a login that isn't the one we prefilled, but
+   * is the same as some other existing login. So, pick a login with a
+   * matching username, or return null.
+   */
+  _repickSelectedLogin(foundLogins, username) {
+    for (var i = 0; i < foundLogins.length; i++) {
+      if (foundLogins[i].username == username) {
+        return foundLogins[i];
+      }
+    }
+    return null;
+  },
+
+  /**
+   * Can be called as:
+   *   _getLocalizedString("key1");
+   *   _getLocalizedString("key2", ["arg1"]);
+   *   _getLocalizedString("key3", ["arg1", "arg2"]);
+   *   (etc)
+   *
+   * Returns the localized string for the specified key,
+   * formatted if required.
+   *
+   */
+  _getLocalizedString(key, formatArgs) {
+    if (formatArgs) {
+      return this._strBundle.formatStringFromName(key, formatArgs);
+    }
+    return this._strBundle.GetStringFromName(key);
+  },
+
+  /**
+   * Sanitizes the specified username, by stripping quotes and truncating if
+   * it's too long. This helps prevent an evil site from messing with the
+   * "save password?" prompt too much.
+   */
+  _sanitizeUsername(username) {
+    if (username.length > 30) {
+      username = username.substring(0, 30);
+      username += this._ellipsis;
+    }
+    return username.replace(/['"]/g, "");
+  },
+
+  /**
+   * The aURI parameter may either be a string uri, or an nsIURI instance.
+   *
+   * Returns the origin to use in a nsILoginInfo object (for example,
+   * "http://example.com").
+   */
+  _getFormattedOrigin(aURI) {
+    let uri;
+    if (aURI instanceof Ci.nsIURI) {
+      uri = aURI;
+    } else {
+      uri = Services.io.newURI(aURI);
+    }
+
+    return uri.scheme + "://" + uri.displayHostPort;
+  },
+
+  /**
+   * Converts a login's origin field (a URL) to a short string for
+   * prompting purposes. Eg, "http://foo.com" --> "foo.com", or
+   * "ftp://www.site.co.uk" --> "site.co.uk".
+   */
+  _getShortDisplayHost(aURIString) {
+    var displayHost;
+
+    var idnService = Cc["@mozilla.org/network/idn-service;1"].getService(
+      Ci.nsIIDNService
+    );
+    try {
+      var uri = Services.io.newURI(aURIString);
+      var baseDomain = Services.eTLD.getBaseDomain(uri);
+      displayHost = idnService.convertToDisplayIDN(baseDomain, {});
+    } catch (e) {
+      this.log(`Couldn't process supplied URIString ${aURIString}.`);
+    }
+
+    if (!displayHost) {
+      displayHost = aURIString;
+    }
+
+    return displayHost;
+  },
+
+  /**
+   * Returns the origin and realm for which authentication is being
+   * requested, in the format expected to be used with nsILoginInfo.
+   */
+  _getAuthTarget(aChannel, aAuthInfo) {
+    var origin, realm;
+
+    // If our proxy is demanding authentication, don't use the
+    // channel's actual destination.
+    if (aAuthInfo.flags & Ci.nsIAuthInformation.AUTH_PROXY) {
+      this.log("getAuthTarget is for proxy auth.");
+      if (!(aChannel instanceof Ci.nsIProxiedChannel)) {
+        throw new Error("proxy auth needs nsIProxiedChannel");
+      }
+
+      var info = aChannel.proxyInfo;
+      if (!info) {
+        throw new Error("proxy auth needs nsIProxyInfo");
+      }
+
+      // Proxies don't have a scheme, but we'll use "moz-proxy://"
+      // so that it's more obvious what the login is for.
+      var idnService = Cc["@mozilla.org/network/idn-service;1"].getService(
+        Ci.nsIIDNService
+      );
+      origin =
+        "moz-proxy://" +
+        idnService.convertUTF8toACE(info.host) +
+        ":" +
+        info.port;
+      realm = aAuthInfo.realm;
+      if (!realm) {
+        realm = origin;
+      }
+
+      return [origin, realm];
+    }
+
+    origin = this._getFormattedOrigin(aChannel.URI);
+
+    // If a HTTP WWW-Authenticate header specified a realm, that value
+    // will be available here. If it wasn't set or wasn't HTTP, we'll use
+    // the formatted origin instead.
+    realm = aAuthInfo.realm;
+    if (!realm) {
+      realm = origin;
+    }
+
+    return [origin, realm];
+  },
+
+  /**
+   * Returns [username, password] as extracted from aAuthInfo (which
+   * holds this info after having prompted the user).
+   *
+   * If the authentication was for a Windows domain, we'll prepend the
+   * return username with the domain. (eg, "domain\user")
+   */
+  _GetAuthInfo(aAuthInfo) {
+    var username, password;
+
+    var flags = aAuthInfo.flags;
+    if (flags & Ci.nsIAuthInformation.NEED_DOMAIN && aAuthInfo.domain) {
+      username = aAuthInfo.domain + "\\" + aAuthInfo.username;
+    } else {
+      username = aAuthInfo.username;
+    }
+
+    password = aAuthInfo.password;
+
+    return [username, password];
+  },
+
+  /**
+   * Given a username (possibly in DOMAIN\user form) and password, parses the
+   * domain out of the username if necessary and sets domain, username and
+   * password on the auth information object.
+   */
+  _SetAuthInfo(aAuthInfo, username, password) {
+    var flags = aAuthInfo.flags;
+    if (flags & Ci.nsIAuthInformation.NEED_DOMAIN) {
+      // Domain is separated from username by a backslash
+      var idx = username.indexOf("\\");
+      if (idx == -1) {
+        aAuthInfo.username = username;
+      } else {
+        aAuthInfo.domain = username.substring(0, idx);
+        aAuthInfo.username = username.substring(idx + 1);
+      }
+    } else {
+      aAuthInfo.username = username;
+    }
+    aAuthInfo.password = password;
+  },
+
+  _newAsyncPromptConsumer(aCallback, aContext) {
+    return {
+      QueryInterface: ChromeUtils.generateQI(["nsICancelable"]),
+      callback: aCallback,
+      context: aContext,
+      cancel() {
+        this.callback.onAuthCancelled(this.context, false);
+        this.callback = null;
+        this.context = null;
+      },
+    };
+  },
+}; // end of LoginManagerAuthPrompter implementation
+
+ChromeUtils.defineLazyGetter(LoginManagerAuthPrompter.prototype, "log", () => {
+  let logger = lazy.LoginHelper.createLogger("LoginManagerAuthPrompter");
+  return logger.log.bind(logger);
+});
+
+XPCOMUtils.defineLazyPreferenceGetter(
+  LoginManagerAuthPrompter,
+  "promptAuthModalType",
+  "prompts.modalType.httpAuth",
+  Services.prompt.MODAL_TYPE_WINDOW
+);
diff --git a/toolkit/components/passwordmgr/LoginManagerChild.sys.mjs b/toolkit/components/passwordmgr/LoginManagerChild.sys.mjs
new file mode 100644
index 0000000000..94be604d02
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginManagerChild.sys.mjs
@@ -0,0 +1,3178 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Module doing most of the content process work for the password manager.
+ */
+
+// Disable use-ownerGlobal since LoginForm doesn't have it.
+/* eslint-disable mozilla/use-ownerGlobal */
+
+const PASSWORD_INPUT_ADDED_COALESCING_THRESHOLD_MS = 1;
+// The amount of time a context menu event supresses showing a
+// popup from a focus event in ms. This matches the threshold in
+// toolkit/components/satchel/nsFormFillController.cpp
+const AUTOCOMPLETE_AFTER_RIGHT_CLICK_THRESHOLD_MS = 400;
+const AUTOFILL_STATE = "autofill";
+
+const SUBMIT_FORM_SUBMIT = 1;
+const SUBMIT_PAGE_NAVIGATION = 2;
+const SUBMIT_FORM_IS_REMOVED = 3;
+
+const LOG_MESSAGE_FORM_SUBMISSION = "form submission";
+const LOG_MESSAGE_FIELD_EDIT = "field edit";
+
+export const AUTOFILL_RESULT = {
+  FILLED: "filled",
+  NO_PASSWORD_FIELD: "no_password_field",
+  PASSWORD_DISABLED_READONLY: "password_disabled_readonly",
+  NO_LOGINS_FIT: "no_logins_fit",
+  NO_SAVED_LOGINS: "no_saved_logins",
+  EXISTING_PASSWORD: "existing_password",
+  EXISTING_USERNAME: "existing_username",
+  MULTIPLE_LOGINS: "multiple_logins",
+  NO_AUTOFILL_FORMS: "no_autofill_forms",
+  AUTOCOMPLETE_OFF: "autocomplete_off",
+  INSECURE: "insecure",
+  PASSWORD_AUTOCOMPLETE_NEW_PASSWORD: "password_autocomplete_new_password",
+  TYPE_NO_LONGER_PASSWORD: "type_no_longer_password",
+  FORM_IN_CROSSORIGIN_SUBFRAME: "form_in_crossorigin_subframe",
+  FILLED_USERNAME_ONLY_FORM: "filled_username_only_form",
+};
+
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+import { AppConstants } from "resource://gre/modules/AppConstants.sys.mjs";
+import { PrivateBrowsingUtils } from "resource://gre/modules/PrivateBrowsingUtils.sys.mjs";
+import { CreditCard } from "resource://gre/modules/CreditCard.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  ContentDOMReference: "resource://gre/modules/ContentDOMReference.sys.mjs",
+  DeferredTask: "resource://gre/modules/DeferredTask.sys.mjs",
+  FormLikeFactory: "resource://gre/modules/FormLikeFactory.sys.mjs",
+  FormScenarios: "resource://gre/modules/FormScenarios.sys.mjs",
+  InsecurePasswordUtils: "resource://gre/modules/InsecurePasswordUtils.sys.mjs",
+  LoginFormFactory: "resource://gre/modules/LoginFormFactory.sys.mjs",
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+  LoginRecipesContent: "resource://gre/modules/LoginRecipes.sys.mjs",
+  LoginManagerTelemetry: "resource://gre/modules/LoginManagerTelemetry.sys.mjs",
+});
+
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "gFormFillService",
+  "@mozilla.org/satchel/form-fill-controller;1",
+  "nsIFormFillController"
+);
+
+ChromeUtils.defineLazyGetter(lazy, "log", () => {
+  let logger = lazy.LoginHelper.createLogger("LoginManagerChild");
+  return logger.log.bind(logger);
+});
+
+Services.cpmm.addMessageListener("clearRecipeCache", () => {
+  lazy.LoginRecipesContent._clearRecipeCache();
+});
+
+let gLastRightClickTimeStamp = Number.NEGATIVE_INFINITY;
+
+// Events on pages with Shadow DOM could return the shadow host element
+// (aEvent.target) rather than the actual username or password field
+// (aEvent.composedTarget).
+// Only allow input elements (can be extended later) to avoid false negatives.
+class WeakFieldSet extends WeakSet {
+  add(value) {
+    if (!HTMLInputElement.isInstance(value)) {
+      throw new Error("Non-field type added to a WeakFieldSet");
+    }
+    super.add(value);
+  }
+}
+
+const observer = {
+  QueryInterface: ChromeUtils.generateQI([
+    "nsIObserver",
+    "nsIWebProgressListener",
+    "nsISupportsWeakReference",
+  ]),
+
+  // nsIWebProgressListener
+  onLocationChange(aWebProgress, aRequest, aLocation, aFlags) {
+    // Only handle pushState/replaceState here.
+    if (
+      !(aFlags & Ci.nsIWebProgressListener.LOCATION_CHANGE_SAME_DOCUMENT) ||
+      !(aWebProgress.loadType & Ci.nsIDocShell.LOAD_CMD_PUSHSTATE)
+    ) {
+      return;
+    }
+
+    const window = aWebProgress.DOMWindow;
+    lazy.log(
+      "onLocationChange handled:",
+      aLocation.displaySpec,
+      window.document
+    );
+    LoginManagerChild.forWindow(window)._onNavigation(window.document);
+  },
+
+  onStateChange(aWebProgress, aRequest, aState, aStatus) {
+    const window = aWebProgress.DOMWindow;
+    const loginManagerChild = () => LoginManagerChild.forWindow(window);
+
+    if (
+      aState & Ci.nsIWebProgressListener.STATE_RESTORING &&
+      aState & Ci.nsIWebProgressListener.STATE_STOP
+    ) {
+      // Re-fill a document restored from bfcache since password field values
+      // aren't persisted there.
+      loginManagerChild()._onDocumentRestored(window.document);
+      return;
+    }
+
+    if (!(aState & Ci.nsIWebProgressListener.STATE_START)) {
+      return;
+    }
+
+    // We only care about when a page triggered a load, not the user. For example:
+    // clicking refresh/back/forward, typing a URL and hitting enter, and loading a bookmark aren't
+    // likely to be when a user wants to save a login.
+    let channel = aRequest.QueryInterface(Ci.nsIChannel);
+    let triggeringPrincipal = channel.loadInfo.triggeringPrincipal;
+    if (
+      triggeringPrincipal.isNullPrincipal ||
+      triggeringPrincipal.equals(
+        Services.scriptSecurityManager.getSystemPrincipal()
+      )
+    ) {
+      return;
+    }
+
+    // Don't handle history navigation, reload, or pushState not triggered via chrome UI.
+    // e.g. history.go(-1), location.reload(), history.replaceState()
+    if (!(aWebProgress.loadType & Ci.nsIDocShell.LOAD_CMD_NORMAL)) {
+      lazy.log(`loadType isn't LOAD_CMD_NORMAL: ${aWebProgress.loadType}.`);
+      return;
+    }
+
+    lazy.log(`Handled channel: ${channel}`);
+    loginManagerChild()._onNavigation(window.document);
+  },
+
+  // nsIObserver
+  observe(subject, topic, data) {
+    switch (topic) {
+      case "autocomplete-did-enter-text": {
+        let input = subject.QueryInterface(Ci.nsIAutoCompleteInput);
+        let { selectedIndex } = input.popup;
+        if (selectedIndex < 0 || selectedIndex >= input.controller.matchCount) {
+          break;
+        }
+
+        let { focusedInput } = lazy.gFormFillService;
+        if (focusedInput.nodePrincipal.isNullPrincipal) {
+          // If we have a null principal then prevent any more password manager code from running and
+          // incorrectly using the document `location`.
+          return;
+        }
+
+        let window = focusedInput.ownerGlobal;
+        let loginManagerChild = LoginManagerChild.forWindow(window);
+
+        let style = input.controller.getStyleAt(selectedIndex);
+        if (style == "login" || style == "loginWithOrigin") {
+          let details = JSON.parse(
+            input.controller.getCommentAt(selectedIndex)
+          );
+          loginManagerChild.onFieldAutoComplete(focusedInput, details.guid);
+        } else if (style == "generatedPassword") {
+          loginManagerChild._filledWithGeneratedPassword(focusedInput);
+        }
+        break;
+      }
+    }
+  },
+
+  // nsIDOMEventListener
+  handleEvent(aEvent) {
+    if (!aEvent.isTrusted) {
+      return;
+    }
+
+    if (!lazy.LoginHelper.enabled) {
+      return;
+    }
+
+    const ownerDocument = aEvent.target.ownerDocument;
+    const window = ownerDocument.defaultView;
+    const loginManagerChild = LoginManagerChild.forWindow(window);
+    const docState = loginManagerChild.stateForDocument(ownerDocument);
+    const field = aEvent.composedTarget;
+
+    switch (aEvent.type) {
+      // Used to mask fields with filled generated passwords when blurred.
+      case "blur":
+        this.handleBlur(docState, field);
+        break;
+
+      // Used to watch for changes to username and password fields.
+      case "change":
+        this.handleChange(docState, field, loginManagerChild);
+        break;
+
+      case "input":
+        this.handleInput(
+          aEvent,
+          docState,
+          field,
+          loginManagerChild,
+          ownerDocument
+        );
+        break;
+
+      case "keydown":
+        this.handleKeydown(aEvent, field, loginManagerChild, ownerDocument);
+        break;
+
+      case "focus":
+        this.handleFocus(field, docState, aEvent.target);
+        break;
+
+      case "mousedown":
+        this.handleMousedown(aEvent.button);
+        break;
+
+      default: {
+        throw new Error("Unexpected event");
+      }
+    }
+  },
+
+  handleBlur(docState, field) {
+    if (docState.generatedPasswordFields.has(field)) {
+      docState._togglePasswordFieldMasking(field, false);
+    }
+  },
+
+  handleChange(docState, field, loginManagerChild) {
+    let formLikeRoot = lazy.FormLikeFactory.findRootForField(field);
+    if (!docState.fieldModificationsByRootElement.get(formLikeRoot)) {
+      lazy.log("Ignoring change event on form that hasn't been user-modified.");
+      if (field.hasBeenTypePassword) {
+        // Send notification that the password field has not been changed.
+        // This is used only for testing.
+        loginManagerChild._ignorePasswordEdit();
+      }
+      return;
+    }
+
+    docState.storeUserInput(field);
+    let detail = {
+      possibleValues: {
+        usernames: docState.possibleUsernames,
+        passwords: docState.possiblePasswords,
+      },
+    };
+    loginManagerChild.sendAsyncMessage(
+      "PasswordManager:updateDoorhangerSuggestions",
+      detail
+    );
+
+    if (field.hasBeenTypePassword) {
+      let triggeredByFillingGenerated =
+        docState.generatedPasswordFields.has(field);
+      // Autosave generated password initial fills and subsequent edits
+      if (triggeredByFillingGenerated) {
+        loginManagerChild._passwordEditedOrGenerated(field, {
+          triggeredByFillingGenerated,
+        });
+      } else {
+        // Send a notification that we are not saving the edit to the password field.
+        // This is used only for testing.
+        loginManagerChild._ignorePasswordEdit();
+      }
+    }
+  },
+
+  handleInput(aEvent, docState, field, loginManagerChild, ownerDocument) {
+    let isPasswordType = lazy.LoginHelper.isPasswordFieldType(field);
+    // React to input into fields filled with generated passwords.
+    if (
+      docState.generatedPasswordFields.has(field) &&
+      // Depending on the edit, we may no longer want to consider
+      // the field a generated password field to avoid autosaving.
+      loginManagerChild._doesEventClearPrevFieldValue(aEvent)
+    ) {
+      docState._stopTreatingAsGeneratedPasswordField(field);
+    }
+
+    if (!isPasswordType && !lazy.LoginHelper.isUsernameFieldType(field)) {
+      return;
+    }
+
+    // React to input into potential username or password fields
+    let formLikeRoot = lazy.FormLikeFactory.findRootForField(field);
+
+    if (formLikeRoot !== aEvent.currentTarget) {
+      return;
+    }
+    // flag this form as user-modified for the closest form/root ancestor
+    let alreadyModified =
+      docState.fieldModificationsByRootElement.get(formLikeRoot);
+    let { login: filledLogin, userTriggered: fillWasUserTriggered } =
+      docState.fillsByRootElement.get(formLikeRoot) || {};
+
+    // don't flag as user-modified if the form was autofilled and doesn't appear to have changed
+    let isAutofillInput = filledLogin && !fillWasUserTriggered;
+    if (!alreadyModified && isAutofillInput) {
+      if (isPasswordType && filledLogin.password == field.value) {
+        lazy.log(
+          "Ignoring password input event that doesn't change autofilled values."
+        );
+        return;
+      }
+      if (
+        !isPasswordType &&
+        filledLogin.usernameField &&
+        filledLogin.username == field.value
+      ) {
+        lazy.log(
+          "Ignoring username input event that doesn't change autofilled values."
+        );
+        return;
+      }
+    }
+    docState.fieldModificationsByRootElement.set(formLikeRoot, true);
+    // Keep track of the modified formless password field to trigger form submission
+    // when it is removed from DOM.
+    let alreadyModifiedFormLessField = true;
+    if (!HTMLFormElement.isInstance(formLikeRoot)) {
+      alreadyModifiedFormLessField =
+        docState.formlessModifiedPasswordFields.has(field);
+      if (!alreadyModifiedFormLessField) {
+        docState.formlessModifiedPasswordFields.add(field);
+      }
+    }
+
+    // Infer form submission only when there has been an user interaction on the form
+    // or the formless password field.
+    if (
+      lazy.LoginHelper.formRemovalCaptureEnabled &&
+      (!alreadyModified || !alreadyModifiedFormLessField)
+    ) {
+      loginManagerChild.registerDOMDocFetchSuccessEventListener(ownerDocument);
+    }
+
+    if (
+      // When the password field value is cleared or entirely replaced we don't treat it as
+      // an autofilled form any more. We don't do the same for username edits to avoid snooping
+      // on the autofilled password in the resulting doorhanger
+      isPasswordType &&
+      loginManagerChild._doesEventClearPrevFieldValue(aEvent) &&
+      // Don't clear last recorded autofill if THIS is an autofilled value. This will be true
+      // when filling from the context menu.
+      filledLogin &&
+      filledLogin.password !== field.value
+    ) {
+      docState.fillsByRootElement.delete(formLikeRoot);
+    }
+
+    if (!lazy.LoginHelper.passwordEditCaptureEnabled) {
+      return;
+    }
+    if (field.hasBeenTypePassword) {
+      // When a field is filled with a generated password, we also fill a confirm password field
+      // if found. To do this, _fillConfirmFieldWithGeneratedPassword calls setUserInput, which fires
+      // an "input" event on the confirm password field. compareAndUpdatePreviouslySentValues will
+      // allow that message through due to triggeredByFillingGenerated, so early return here.
+      let form = lazy.LoginFormFactory.createFromField(field);
+      if (
+        docState.generatedPasswordFields.has(field) &&
+        docState._getFormFields(form).confirmPasswordField === field
+      ) {
+        return;
+      }
+      // Don't check for triggeredByFillingGenerated, as we do not want to autosave
+      // a field marked as a generated password field on every "input" event
+      loginManagerChild._passwordEditedOrGenerated(field);
+    } else {
+      let [usernameField, passwordField] =
+        docState.getUserNameAndPasswordFields(field);
+      if (field == usernameField && passwordField?.value) {
+        loginManagerChild._passwordEditedOrGenerated(passwordField, {
+          triggeredByFillingGenerated:
+            docState.generatedPasswordFields.has(passwordField),
+        });
+      }
+    }
+  },
+
+  handleKeydown(aEvent, field, loginManagerChild, ownerDocument) {
+    if (
+      field.value &&
+      (aEvent.keyCode == aEvent.DOM_VK_TAB ||
+        aEvent.keyCode == aEvent.DOM_VK_RETURN)
+    ) {
+      const autofillForm =
+        lazy.LoginHelper.autofillForms &&
+        !PrivateBrowsingUtils.isContentWindowPrivate(ownerDocument.defaultView);
+
+      if (autofillForm) {
+        loginManagerChild.onUsernameAutocompleted(field);
+      }
+    }
+  },
+
+  handleFocus(field, docState, target) {
+    //@sg see if we can drop focusedField (aEvent.target) and use field (aEvent.composedTarget)
+    docState.onFocus(field, target);
+  },
+
+  handleMousedown(button) {
+    if (button == 2) {
+      // Date.now() is used instead of event.timeStamp since
+      // dom.event.highrestimestamp.enabled isn't true on all channels yet.
+      gLastRightClickTimeStamp = Date.now();
+    }
+  },
+};
+
+// Add this observer once for the process.
+Services.obs.addObserver(observer, "autocomplete-did-enter-text");
+
+/**
+ * Form scenario defines what can be done with form.
+ */
+class FormScenario {}
+
+/**
+ * Sign up scenario defines typical account registration flow.
+ */
+class SignUpFormScenario extends FormScenario {
+  usernameField;
+  passwordField;
+}
+
+/**
+ * Logic of Capture and Filling.
+ *
+ * This class will be shared with Firefox iOS and should have no references to
+ * Gecko internals. See Bug 1774208.
+ */
+export class LoginFormState {
+  /**
+   * Keeps track of filled fields and values.
+   */
+  fillsByRootElement = new WeakMap();
+  /**
+   * Keeps track of fields we've filled with generated passwords
+   */
+  generatedPasswordFields = new WeakFieldSet();
+  /**
+   * Keeps track of logins that were last submitted.
+   */
+  lastSubmittedValuesByRootElement = new WeakMap();
+  fieldModificationsByRootElement = new WeakMap();
+  /**
+   * Anything entered into an <input> that we think might be a username
+   */
+  possibleUsernames = new Set();
+  /**
+   * Anything entered into an <input> that we think might be a password
+   */
+  possiblePasswords = new Set();
+
+  /**
+   * Keeps track of the formLike of nodes (form or formless password field)
+   * that we are watching when they are removed from DOM.
+   */
+  formLikeByObservedNode = new WeakMap();
+
+  /**
+   * Keeps track of all formless password fields that have been
+   * updated by the user.
+   */
+  formlessModifiedPasswordFields = new WeakFieldSet();
+
+  /**
+   * Caches the results of the username heuristics
+   */
+  #cachedIsInferredUsernameField = new WeakMap();
+  #cachedIsInferredEmailField = new WeakMap();
+  #cachedIsInferredLoginForm = new WeakMap();
+
+  /**
+   * Records the mock username field when its associated form is submitted.
+   */
+  mockUsernameOnlyField = null;
+
+  /**
+   * Records the number of possible username event received for this document.
+   */
+  numFormHasPossibleUsernameEvent = 0;
+
+  captureLoginTimeStamp = 0;
+
+  // Scenarios detected on this page
+  #scenariosByRoot = new WeakMap();
+
+  getScenario(inputElement) {
+    const formLikeRoot = lazy.FormLikeFactory.findRootForField(inputElement);
+    return this.#scenariosByRoot.get(formLikeRoot);
+  }
+
+  setScenario(formLikeRoot, scenario) {
+    this.#scenariosByRoot.set(formLikeRoot, scenario);
+  }
+
+  storeUserInput(field) {
+    if (field.value && lazy.LoginHelper.captureInputChanges) {
+      if (lazy.LoginHelper.isPasswordFieldType(field)) {
+        this.possiblePasswords.add(field.value);
+      } else if (lazy.LoginHelper.isUsernameFieldType(field)) {
+        this.possibleUsernames.add(field.value);
+      }
+    }
+  }
+
+  /**
+   * Returns true if the input field is considered an email field by
+   * 'LoginHelper.isInferredEmailField'.
+   *
+   * @param {Element} element the field to check.
+   * @returns {boolean} True if the element is likely an email field
+   */
+  isProbablyAnEmailField(inputElement) {
+    if (!inputElement) {
+      return false;
+    }
+
+    let result = this.#cachedIsInferredEmailField.get(inputElement);
+    if (result === undefined) {
+      result = lazy.LoginHelper.isInferredEmailField(inputElement);
+      this.#cachedIsInferredEmailField.set(inputElement, result);
+    }
+
+    return result;
+  }
+
+  /**
+   * Returns true if the input field is considered a username field by
+   * 'LoginHelper.isInferredUsernameField'. The main purpose of this method
+   * is to cache the result because _getFormFields has many call sites and we
+   * want to avoid applying the heuristic every time.
+   *
+   * @param {Element} element the field to check.
+   * @returns {boolean} True if the element is likely a username field
+   */
+  isProbablyAUsernameField(inputElement) {
+    let result = this.#cachedIsInferredUsernameField.get(inputElement);
+    if (result === undefined) {
+      result = lazy.LoginHelper.isInferredUsernameField(inputElement);
+      this.#cachedIsInferredUsernameField.set(inputElement, result);
+    }
+
+    return result;
+  }
+
+  /**
+   * Returns true if the form is considered a username login form if
+   * 1. The input element looks like a username field or the form looks
+   *    like a login form
+   * 2. The input field doesn't match keywords that indicate the username
+   *    is not used for login (ex, search) or the login form is not use
+   *    a username to sign-in (ex, authentication code)
+   *
+   * @param {Element} element the form to check.
+   * @returns {boolean} True if the element is likely a login form
+   */
+  #isProbablyAUsernameLoginForm(formElement, inputElement) {
+    let result = this.#cachedIsInferredLoginForm.get(formElement);
+    if (result === undefined) {
+      // We should revisit these rules after we collect more positive or negative
+      // cases for username-only forms. Right now, if-else-based rules are good
+      // enough to cover the sites we know, but if we find out defining "weight" for each
+      // rule is necessary to improve the heuristic, we should consider switching
+      // this with Fathom.
+
+      result = false;
+      // Check whether the input field looks like a username field or the
+      // form looks like a sign-in or sign-up form.
+      if (
+        this.isProbablyAUsernameField(inputElement) ||
+        lazy.LoginHelper.isInferredLoginForm(formElement)
+      ) {
+        // This is where we collect hints that indicate this is not a username
+        // login form.
+        if (!lazy.LoginHelper.isInferredNonUsernameField(inputElement)) {
+          result = true;
+        }
+      }
+      this.#cachedIsInferredLoginForm.set(formElement, result);
+    }
+
+    return result;
+  }
+
+  /**
+   * Given a field, determine whether that field was last filled as a username
+   * field AND whether the username is still filled in with the username AND
+   * whether the associated password field has the matching password.
+   *
+   * @note This could possibly be unified with getFieldContext but they have
+   * slightly different use cases. getFieldContext looks up recipes whereas this
+   * method doesn't need to since it's only returning a boolean based upon the
+   * recipes used for the last fill (in _fillForm).
+   *
+   * @param {HTMLInputElement} aUsernameField element contained in a LoginForm
+   *                                          cached in LoginFormFactory.
+   * @returns {Boolean} whether the username and password fields still have the
+   *                    last-filled values, if previously filled.
+   */
+  #isLoginAlreadyFilled(aUsernameField) {
+    let formLikeRoot = lazy.FormLikeFactory.findRootForField(aUsernameField);
+    // Look for the existing LoginForm.
+    let existingLoginForm =
+      lazy.LoginFormFactory.getForRootElement(formLikeRoot);
+    if (!existingLoginForm) {
+      throw new Error(
+        "#isLoginAlreadyFilled called with a username field with " +
+          "no rootElement LoginForm"
+      );
+    }
+
+    let { login: filledLogin } =
+      this.fillsByRootElement.get(formLikeRoot) || {};
+    if (!filledLogin) {
+      return false;
+    }
+
+    // Unpack the weak references.
+    let autoFilledUsernameField = filledLogin.usernameField?.get();
+    let autoFilledPasswordField = filledLogin.passwordField?.get();
+
+    // Check username and password values match what was filled.
+    if (
+      !autoFilledUsernameField ||
+      autoFilledUsernameField != aUsernameField ||
+      autoFilledUsernameField.value != filledLogin.username ||
+      (autoFilledPasswordField &&
+        autoFilledPasswordField.value != filledLogin.password)
+    ) {
+      return false;
+    }
+
+    return true;
+  }
+
+  _togglePasswordFieldMasking(passwordField, unmask) {
+    let { editor } = passwordField;
+
+    if (passwordField.type != "password") {
+      // The type may have been changed by the website.
+      lazy.log("Field isn't type=password.");
+      return;
+    }
+
+    if (!unmask && !editor) {
+      // It hasn't been created yet but the default is to be masked anyways.
+      return;
+    }
+
+    if (unmask) {
+      editor.unmask(0);
+      return;
+    }
+
+    if (editor.autoMaskingEnabled) {
+      return;
+    }
+    editor.mask();
+  }
+
+  /**
+   * Track a form field as has having been filled with a generated password. This adds explicit
+   * focus & blur handling to unmask & mask the value, and enables special handling of edits to
+   * generated password values (see the observer's input event handler.)
+   *
+   * @param {HTMLInputElement} passwordField
+   */
+  _treatAsGeneratedPasswordField(passwordField) {
+    this.generatedPasswordFields.add(passwordField);
+
+    // blur/focus: listen for focus changes to we can mask/unmask generated passwords
+    for (let eventType of ["blur", "focus"]) {
+      passwordField.addEventListener(eventType, observer, {
+        capture: true,
+        mozSystemGroup: true,
+      });
+    }
+    if (passwordField.ownerDocument.activeElement == passwordField) {
+      // Unmask the password field
+      this._togglePasswordFieldMasking(passwordField, true);
+    }
+  }
+
+  _formHasModifiedFields(form) {
+    const doc = form.rootElement.ownerDocument;
+    let userHasInteracted;
+    const testOnlyUserHasInteracted =
+      lazy.LoginHelper.testOnlyUserHasInteractedWithDocument;
+    if (Cu.isInAutomation && testOnlyUserHasInteracted !== null) {
+      userHasInteracted = testOnlyUserHasInteracted;
+    } else {
+      userHasInteracted =
+        !lazy.LoginHelper.userInputRequiredToCapture ||
+        this.captureLoginTimeStamp != doc.lastUserGestureTimeStamp;
+    }
+
+    lazy.log(
+      `_formHasModifiedFields: userHasInteracted: ${userHasInteracted}.`
+    );
+
+    // Skip if user didn't interact with the page since last call or ever
+    if (!userHasInteracted) {
+      return false;
+    }
+
+    // check for user inputs to the form fields
+    let fieldsModified = this.fieldModificationsByRootElement.get(
+      form.rootElement
+    );
+    // also consider a form modified if there's a difference between fields' .value and .defaultValue
+    if (!fieldsModified) {
+      fieldsModified = Array.from(form.elements).some(
+        field =>
+          field.defaultValue !== undefined && field.value !== field.defaultValue
+      );
+    }
+    return fieldsModified;
+  }
+
+  _stopTreatingAsGeneratedPasswordField(passwordField) {
+    this.generatedPasswordFields.delete(passwordField);
+
+    // Remove all the event listeners added in _passwordEditedOrGenerated
+    for (let eventType of ["blur", "focus"]) {
+      passwordField.removeEventListener(eventType, observer, {
+        capture: true,
+        mozSystemGroup: true,
+      });
+    }
+
+    // Mask the password field
+    this._togglePasswordFieldMasking(passwordField, false);
+  }
+
+  onFocus(field, focusedField) {
+    if (field.hasBeenTypePassword && this.generatedPasswordFields.has(field)) {
+      // Used to unmask fields with filled generated passwords when focused.
+      this._togglePasswordFieldMasking(field, true);
+      return;
+    }
+
+    // Only used for username fields.
+    this.#onUsernameFocus(focusedField);
+  }
+
+  /**
+   * Focus event handler for username fields to decide whether to show autocomplete.
+   * @param {HTMLInputElement} focusedField
+   */
+  #onUsernameFocus(focusedField) {
+    if (
+      !focusedField.mozIsTextField(true) ||
+      focusedField.hasBeenTypePassword ||
+      focusedField.readOnly
+    ) {
+      return;
+    }
+
+    if (this.#isLoginAlreadyFilled(focusedField)) {
+      lazy.log("Login already filled.");
+      return;
+    }
+
+    /*
+     * A `mousedown` event is fired before the `focus` event if the user right clicks into an
+     * unfocused field. In that case we don't want to show both autocomplete and a context menu
+     * overlapping so we check against the timestamp that was set by the `mousedown` event if the
+     * button code indicated a right click.
+     * We use a timestamp instead of a bool to avoid complexity when dealing with multiple input
+     * forms and the fact that a mousedown into an already focused field does not trigger another focus.
+     * Date.now() is used instead of event.timeStamp since dom.event.highrestimestamp.enabled isn't
+     * true on all channels yet.
+     */
+    let timeDiff = Date.now() - gLastRightClickTimeStamp;
+    if (timeDiff < AUTOCOMPLETE_AFTER_RIGHT_CLICK_THRESHOLD_MS) {
+      lazy.log(
+        `Not opening autocomplete after focus since a context menu was opened within ${timeDiff}ms.`
+      );
+      return;
+    }
+
+    // The login manager is responsible for fields with the "webauthn" credential type.
+    let acCredentialType = focusedField.getAutocompleteInfo()?.credentialType;
+    if (acCredentialType == "webauthn") {
+      lazy.gFormFillService.markAsLoginManagerField(focusedField);
+    }
+
+    lazy.log("Opening the autocomplete popup.");
+    lazy.gFormFillService.showPopup();
+  }
+
+  /** Remove login field highlight when its value is cleared or overwritten.
+   */
+  static #removeFillFieldHighlight(event) {
+    let winUtils = event.target.ownerGlobal.windowUtils;
+    winUtils.removeManuallyManagedState(event.target, AUTOFILL_STATE);
+  }
+
+  /**
+   * Highlight login fields on autocomplete or autofill on page load.
+   * @param {Node} element that needs highlighting.
+   */
+  static _highlightFilledField(element) {
+    let winUtils = element.ownerGlobal.windowUtils;
+
+    winUtils.addManuallyManagedState(element, AUTOFILL_STATE);
+    // Remove highlighting when the field is changed.
+    element.addEventListener(
+      "input",
+      LoginFormState.#removeFillFieldHighlight,
+      {
+        mozSystemGroup: true,
+        once: true,
+      }
+    );
+  }
+
+  /**
+   * Returns the username field of the passed form if the form is a
+   * username-only form.
+   * A form is considered a username-only form only if it meets all the
+   * following conditions:
+   * 1. Does not have any password field,
+   * 2. Only contains one input field whose type is username compatible.
+   * 3. The username compatible input field looks like a username field
+   *    or the form itself looks like a sign-in or sign-up form.
+   *
+   * @param {Element} formElement
+   *                  the form to check.
+   * @param {Object}  recipe=null
+   *                  A relevant field override recipe to use.
+   * @returns {Element} The username field or null (if the form is not a
+   *                    username-only form).
+   */
+  getUsernameFieldFromUsernameOnlyForm(formElement, recipe = null) {
+    if (!HTMLFormElement.isInstance(formElement)) {
+      return null;
+    }
+
+    let candidate = null;
+    for (let element of formElement.elements) {
+      // We are looking for a username-only form, so if there is a password
+      // field in the form, this is NOT a username-only form.
+      if (element.hasBeenTypePassword) {
+        return null;
+      }
+
+      // Ignore input fields whose type are not username compatiable, ex, hidden.
+      if (!lazy.LoginHelper.isUsernameFieldType(element)) {
+        continue;
+      }
+
+      if (
+        recipe?.notUsernameSelector &&
+        element.matches(recipe.notUsernameSelector)
+      ) {
+        continue;
+      }
+
+      // If there are more than two input fields whose type is username
+      // compatiable, this is NOT a username-only form.
+      if (candidate) {
+        return null;
+      }
+      candidate = element;
+    }
+
+    if (
+      candidate &&
+      this.#isProbablyAUsernameLoginForm(formElement, candidate)
+    ) {
+      return candidate;
+    }
+
+    return null;
+  }
+
+  /**
+   * @param {LoginForm} form - the LoginForm to look for password fields in.
+   * @param {Object} options
+   * @param {bool} [options.skipEmptyFields=false] - Whether to ignore password fields with no value.
+   *                                                 Used at capture time since saving empty values isn't
+   *                                                 useful.
+   * @param {Object} [options.fieldOverrideRecipe=null] - A relevant field override recipe to use.
+   * @return {Array|null} Array of password field elements for the specified form.
+   *                      If no pw fields are found, or if more than 5 are found, then null
+   *                      is returned.
+   */
+  static _getPasswordFields(
+    form,
+    {
+      fieldOverrideRecipe = null,
+      minPasswordLength = 0,
+      ignoreConnect = false,
+    } = {}
+  ) {
+    // Locate the password fields in the form.
+    let pwFields = [];
+    for (let i = 0; i < form.elements.length; i++) {
+      let element = form.elements[i];
+      if (
+        !HTMLInputElement.isInstance(element) ||
+        !element.hasBeenTypePassword ||
+        (!element.isConnected && !ignoreConnect)
+      ) {
+        continue;
+      }
+
+      // Exclude ones matching a `notPasswordSelector`, if specified.
+      if (
+        fieldOverrideRecipe?.notPasswordSelector &&
+        element.matches(fieldOverrideRecipe.notPasswordSelector)
+      ) {
+        lazy.log(
+          `Skipping password field with id: ${element.id}, name: ${element.name} due to recipe ${fieldOverrideRecipe}.`
+        );
+        continue;
+      }
+
+      // XXX: Bug 780449 tracks our handling of emoji and multi-code-point characters in
+      // password fields. To avoid surprises, we should be consistent with the visual
+      // representation of the masked password
+      if (
+        minPasswordLength &&
+        element.value.trim().length < minPasswordLength
+      ) {
+        lazy.log(
+          `Skipping password field with id: ${element.id}, name: ${element.name} as value is too short.`
+        );
+        continue; // Ignore empty or too-short passwords fields
+      }
+
+      pwFields[pwFields.length] = {
+        index: i,
+        element,
+      };
+    }
+
+    // If too few or too many fields, bail out.
+    if (!pwFields.length) {
+      lazy.log("Form ignored, no password fields.");
+      return null;
+    }
+
+    if (pwFields.length > 5) {
+      lazy.log(`Form ignored, too many password fields:  ${pwFields.length}.`);
+      return null;
+    }
+
+    return pwFields;
+  }
+
+  /**
+   * Stores passed arguments, and returns whether or not they match the args given the last time
+   * this method was called with the same [formLikeRoot]. This is used to avoid sending duplicate
+   * messages to the parent.
+   *
+   * @param {Element} formLikeRoot
+   * @param {string} usernameValue
+   * @param {string} passwordValue
+   * @param {boolean?} [dismissed=false]
+   * @param {boolean?} [triggeredByFillingGenerated=false] whether or not this call was triggered by a generated
+   *        password being filled into a form-like element.
+   *
+   * @returns {boolean} true if args match the most recently passed values
+   */
+  compareAndUpdatePreviouslySentValues(
+    formLikeRoot,
+    usernameValue,
+    passwordValue,
+    dismissed = false,
+    triggeredByFillingGenerated = false
+  ) {
+    const lastSentValues =
+      this.lastSubmittedValuesByRootElement.get(formLikeRoot);
+    if (lastSentValues) {
+      if (dismissed && !lastSentValues.dismissed) {
+        // preserve previous dismissed value if it was false (i.e. shown/open)
+        dismissed = false;
+      }
+      if (
+        lastSentValues.username == usernameValue &&
+        lastSentValues.password == passwordValue &&
+        lastSentValues.dismissed == dismissed &&
+        lastSentValues.triggeredByFillingGenerated ==
+          triggeredByFillingGenerated
+      ) {
+        lazy.log(
+          "compareAndUpdatePreviouslySentValues: values are equivalent, returning true."
+        );
+        return true;
+      }
+    }
+
+    // Save the last submitted values so we don't prompt twice for the same values using
+    // different capture methods e.g. a form submit event and upon navigation.
+    this.lastSubmittedValuesByRootElement.set(formLikeRoot, {
+      username: usernameValue,
+      password: passwordValue,
+      dismissed,
+      triggeredByFillingGenerated,
+    });
+    lazy.log(
+      "compareAndUpdatePreviouslySentValues: values not equivalent, returning false."
+    );
+    return false;
+  }
+
+  fillConfirmFieldWithGeneratedPassword(passwordField) {
+    // Fill a nearby password input if it looks like a confirm-password field
+    let form = lazy.LoginFormFactory.createFromField(passwordField);
+    let confirmPasswordInput = null;
+    // The confirm-password field shouldn't be more than 3 form elements away from the password field we filled
+    let MAX_CONFIRM_PASSWORD_DISTANCE = 3;
+
+    let startIndex = form.elements.indexOf(passwordField);
+    if (startIndex == -1) {
+      throw new Error(
+        "Password field is not in the form's elements collection"
+      );
+    }
+
+    // If we've already filled another field with a generated password,
+    // this might be the confirm-password field, so don't try and find another
+    let previousGeneratedPasswordField = form.elements.some(
+      inp => inp !== passwordField && this.generatedPasswordFields.has(inp)
+    );
+    if (previousGeneratedPasswordField) {
+      lazy.log("Previously-filled generated password input found.");
+      return;
+    }
+
+    // Get a list of input fields to search in.
+    // Pre-filter type=hidden fields; they don't count against the distance threshold
+    let afterFields = form.elements
+      .slice(startIndex + 1)
+      .filter(elem => elem.type !== "hidden");
+
+    let acFieldName = passwordField.getAutocompleteInfo()?.fieldName;
+
+    // Match same autocomplete values first
+    if (acFieldName == "new-password") {
+      let matchIndex = afterFields.findIndex(
+        elem =>
+          lazy.LoginHelper.isPasswordFieldType(elem) &&
+          elem.getAutocompleteInfo().fieldName == acFieldName &&
+          !elem.disabled &&
+          !elem.readOnly
+      );
+      if (matchIndex >= 0 && matchIndex < MAX_CONFIRM_PASSWORD_DISTANCE) {
+        confirmPasswordInput = afterFields[matchIndex];
+      }
+    }
+    if (!confirmPasswordInput) {
+      for (
+        let idx = 0;
+        idx < Math.min(MAX_CONFIRM_PASSWORD_DISTANCE, afterFields.length);
+        idx++
+      ) {
+        if (
+          lazy.LoginHelper.isPasswordFieldType(afterFields[idx]) &&
+          !afterFields[idx].disabled &&
+          !afterFields[idx].readOnly
+        ) {
+          confirmPasswordInput = afterFields[idx];
+          break;
+        }
+      }
+    }
+    if (confirmPasswordInput && !confirmPasswordInput.value) {
+      this._treatAsGeneratedPasswordField(confirmPasswordInput);
+      confirmPasswordInput.setUserInput(passwordField.value);
+      LoginFormState._highlightFilledField(confirmPasswordInput);
+    }
+  }
+
+  /**
+   * Returns the username and password fields found in the form.
+   * Can handle complex forms by trying to figure out what the
+   * relevant fields are.
+   *
+   * @param {LoginForm} form
+   * @param {bool} isSubmission
+   * @param {Set} recipes
+   * @param {Object} options
+   * @param {bool} [options.ignoreConnect] - Whether to ignore checking isConnected
+   *                                         of the element.
+   * @return {Object} {usernameField, newPasswordField, oldPasswordField, confirmPasswordField}
+   *
+   * usernameField may be null.
+   * newPasswordField may be null. If null, this is a username-only form.
+   * oldPasswordField may be null. If null, newPasswordField is just
+   * "theLoginField". If not null, the form is apparently a
+   * change-password field, with oldPasswordField containing the password
+   * that is being changed.
+   *
+   * Note that even though we can create a LoginForm from a text field,
+   * this method will only return a non-null usernameField if the
+   * LoginForm has a password field.
+   */
+  _getFormFields(form, isSubmission, recipes, { ignoreConnect = false } = {}) {
+    let usernameField = null;
+    let newPasswordField = null;
+    let oldPasswordField = null;
+    let confirmPasswordField = null;
+    let emptyResult = {
+      usernameField: null,
+      newPasswordField: null,
+      oldPasswordField: null,
+      confirmPasswordField: null,
+    };
+
+    let pwFields = null;
+    let fieldOverrideRecipe = lazy.LoginRecipesContent.getFieldOverrides(
+      recipes,
+      form
+    );
+    if (fieldOverrideRecipe) {
+      lazy.log("fieldOverrideRecipe found ", fieldOverrideRecipe);
+      let pwOverrideField = lazy.LoginRecipesContent.queryLoginField(
+        form,
+        fieldOverrideRecipe.passwordSelector
+      );
+      if (pwOverrideField) {
+        lazy.log("pwOverrideField found ", pwOverrideField);
+        // The field from the password override may be in a different LoginForm.
+        let formLike = lazy.LoginFormFactory.createFromField(pwOverrideField);
+        pwFields = [
+          {
+            index: [...formLike.elements].indexOf(pwOverrideField),
+            element: pwOverrideField,
+          },
+        ];
+      }
+
+      let usernameOverrideField = lazy.LoginRecipesContent.queryLoginField(
+        form,
+        fieldOverrideRecipe.usernameSelector
+      );
+      if (usernameOverrideField) {
+        usernameField = usernameOverrideField;
+      }
+    }
+
+    if (!pwFields) {
+      // Locate the password field(s) in the form. Up to 5 supported.
+      // If there's no password field, there's nothing for us to do.
+      const minSubmitPasswordLength = 2;
+      pwFields = LoginFormState._getPasswordFields(form, {
+        fieldOverrideRecipe,
+        minPasswordLength: isSubmission ? minSubmitPasswordLength : 0,
+        ignoreConnect,
+      });
+    }
+
+    // Check whether this is a username-only form when the form doesn't have
+    // a password field. Note that recipes are not supported in username-only
+    // forms currently (Bug 1708455).
+    if (!pwFields) {
+      if (!lazy.LoginHelper.usernameOnlyFormEnabled) {
+        return emptyResult;
+      }
+
+      usernameField = this.getUsernameFieldFromUsernameOnlyForm(
+        form.rootElement,
+        fieldOverrideRecipe
+      );
+
+      if (usernameField) {
+        lazy.log(`Found username field with name: ${usernameField.name}.`);
+      }
+
+      return {
+        ...emptyResult,
+        usernameField,
+      };
+    }
+
+    if (!usernameField) {
+      // Searching backwards from the first password field until we find a field
+      // that looks like a "username" field. If no "username" field is found,
+      // consider an email-like field a username field, if any.
+      // If neither a username-like or an email-like field exists, assume the
+      // first text field before the password field is the username.
+      // We might not find a username field if the user is already logged in to the site.
+      //
+      // Note: We only search fields precede the first password field because we
+      // don't see sites putting a username field after a password field. We can
+      // extend searching to all fields in the form if this turns out not to be the case.
+
+      for (let i = pwFields[0].index - 1; i >= 0; i--) {
+        let element = form.elements[i];
+        if (!lazy.LoginHelper.isUsernameFieldType(element, { ignoreConnect })) {
+          continue;
+        }
+
+        if (
+          fieldOverrideRecipe?.notUsernameSelector &&
+          element.matches(fieldOverrideRecipe.notUsernameSelector)
+        ) {
+          continue;
+        }
+
+        // Assume the first text field is the username by default.
+        // It will be replaced if we find a likely username field afterward.
+        if (!usernameField) {
+          usernameField = element;
+        }
+
+        if (this.isProbablyAUsernameField(element)) {
+          // An username field is found, we are done.
+          usernameField = element;
+          break;
+        } else if (this.isProbablyAnEmailField(element)) {
+          // An email field is found, consider it a username field but continue
+          // to search for an "username" field.
+          // In current implementation, if another email field is found during
+          // the process, we will use the new one.
+          usernameField = element;
+        }
+      }
+    }
+
+    if (!usernameField) {
+      lazy.log("No username field found.");
+    } else {
+      lazy.log(`Found username field with name: ${usernameField.name}.`);
+    }
+
+    let pwGeneratedFields = pwFields.filter(pwField =>
+      this.generatedPasswordFields.has(pwField.element)
+    );
+    if (pwGeneratedFields.length) {
+      // we have at least the newPasswordField
+      [newPasswordField, confirmPasswordField] = pwGeneratedFields.map(
+        pwField => pwField.element
+      );
+      // if the user filled a field with a generated password,
+      // a field immediately previous to that is most likely the old password field
+      let idx = pwFields.findIndex(
+        pwField => pwField.element === newPasswordField
+      );
+      if (idx > 0) {
+        oldPasswordField = pwFields[idx - 1].element;
+      }
+      return {
+        ...emptyResult,
+        usernameField,
+        newPasswordField,
+        oldPasswordField: oldPasswordField || null,
+        confirmPasswordField: confirmPasswordField || null,
+      };
+    }
+
+    // If we're not submitting a form (it's a page load), there are no
+    // password field values for us to use for identifying fields. So,
+    // just assume the first password field is the one to be filled in.
+    if (!isSubmission || pwFields.length == 1) {
+      let passwordField = pwFields[0].element;
+      lazy.log(`Found Password field with name: ${passwordField.name}.`);
+      return {
+        ...emptyResult,
+        usernameField,
+        newPasswordField: passwordField,
+        oldPasswordField: null,
+      };
+    }
+
+    // We're looking for both new and old password field
+    // Try to figure out what is in the form based on the password values.
+    let pw1 = pwFields[0].element.value;
+    let pw2 = pwFields[1] ? pwFields[1].element.value : null;
+    let pw3 = pwFields[2] ? pwFields[2].element.value : null;
+
+    if (pwFields.length == 3) {
+      // Look for two identical passwords, that's the new password
+
+      if (pw1 == pw2 && pw2 == pw3) {
+        // All 3 passwords the same? Weird! Treat as if 1 pw field.
+        newPasswordField = pwFields[0].element;
+        oldPasswordField = null;
+      } else if (pw1 == pw2) {
+        newPasswordField = pwFields[0].element;
+        oldPasswordField = pwFields[2].element;
+      } else if (pw2 == pw3) {
+        oldPasswordField = pwFields[0].element;
+        newPasswordField = pwFields[2].element;
+      } else if (pw1 == pw3) {
+        // A bit odd, but could make sense with the right page layout.
+        newPasswordField = pwFields[0].element;
+        oldPasswordField = pwFields[1].element;
+      } else {
+        // We can't tell which of the 3 passwords should be saved.
+        lazy.log(`Form ignored -- all 3 pw fields differ.`);
+        return emptyResult;
+      }
+    } else if (pw1 == pw2) {
+      // pwFields.length == 2
+      // Treat as if 1 pw field
+      newPasswordField = pwFields[0].element;
+      oldPasswordField = null;
+    } else {
+      // Just assume that the 2nd password is the new password
+      oldPasswordField = pwFields[0].element;
+      newPasswordField = pwFields[1].element;
+    }
+
+    lazy.log(
+      `New Password field id: ${newPasswordField.id}, name: ${newPasswordField.name}.`
+    );
+
+    lazy.log(
+      oldPasswordField
+        ? `Old Password field id: ${oldPasswordField.id}, name: ${oldPasswordField.name}.`
+        : "No Old password field."
+    );
+    return {
+      ...emptyResult,
+      usernameField,
+      newPasswordField,
+      oldPasswordField,
+    };
+  }
+
+  /**
+   * Returns the username and password fields found in the form by input
+   * element into form.
+   *
+   * @param {HTMLInputElement} aField
+   *                           A form field
+   * @return {Array} [usernameField, newPasswordField, oldPasswordField]
+   *
+   * Details of these values are the same as _getFormFields.
+   */
+  getUserNameAndPasswordFields(aField) {
+    const noResult = [null, null, null];
+    if (!HTMLInputElement.isInstance(aField)) {
+      throw new Error("getUserNameAndPasswordFields: input element required");
+    }
+
+    if (aField.nodePrincipal.isNullPrincipal || !aField.isConnected) {
+      return noResult;
+    }
+
+    // If the element is not a login form field, return all null.
+    if (
+      !aField.hasBeenTypePassword &&
+      !lazy.LoginHelper.isUsernameFieldType(aField)
+    ) {
+      return noResult;
+    }
+
+    const form = lazy.LoginFormFactory.createFromField(aField);
+    const doc = aField.ownerDocument;
+    const formOrigin = lazy.LoginHelper.getLoginOrigin(doc.documentURI);
+    const recipes = lazy.LoginRecipesContent.getRecipes(
+      formOrigin,
+      doc.defaultView
+    );
+    const { usernameField, newPasswordField, oldPasswordField } =
+      this._getFormFields(form, false, recipes);
+
+    return [usernameField, newPasswordField, oldPasswordField];
+  }
+
+  /**
+   * Verify if a field is a valid login form field and
+   * returns some information about it's LoginForm.
+   *
+   * @param {Element} aField
+   *                  A form field we want to verify.
+   *
+   * @returns {Object} an object with information about the
+   *                   LoginForm username and password field
+   *                   or null if the passed field is invalid.
+   */
+  getFieldContext(aField) {
+    // If the element is not a proper form field, return null.
+    if (
+      !HTMLInputElement.isInstance(aField) ||
+      (!aField.hasBeenTypePassword &&
+        !lazy.LoginHelper.isUsernameFieldType(aField)) ||
+      aField.nodePrincipal.isNullPrincipal ||
+      aField.nodePrincipal.schemeIs("about") ||
+      !aField.ownerDocument
+    ) {
+      return null;
+    }
+    let { hasBeenTypePassword } = aField;
+
+    // This array provides labels that correspond to the return values from
+    // `getUserNameAndPasswordFields` so we can know which one aField is.
+    const LOGIN_FIELD_ORDER = ["username", "new-password", "current-password"];
+    let usernameAndPasswordFields = this.getUserNameAndPasswordFields(aField);
+    let fieldNameHint;
+    let indexOfFieldInUsernameAndPasswordFields =
+      usernameAndPasswordFields.indexOf(aField);
+    if (indexOfFieldInUsernameAndPasswordFields == -1) {
+      // For fields in the form that are neither username nor password,
+      // set fieldNameHint to "other". Right now, in contextmenu, we treat both
+      // "username" and "other" field as username fields.
+      fieldNameHint = hasBeenTypePassword ? "current-password" : "other";
+    } else {
+      fieldNameHint =
+        LOGIN_FIELD_ORDER[indexOfFieldInUsernameAndPasswordFields];
+    }
+    let [, newPasswordField] = usernameAndPasswordFields;
+
+    return {
+      activeField: {
+        disabled: aField.disabled || aField.readOnly,
+        fieldNameHint,
+      },
+      // `passwordField` may be the same as `activeField`.
+      passwordField: {
+        found: !!newPasswordField,
+        disabled:
+          newPasswordField &&
+          (newPasswordField.disabled || newPasswordField.readOnly),
+      },
+    };
+  }
+}
+
+/**
+ * Integration with browser and IPC with LoginManagerParent.
+ *
+ * NOTE: there are still bits of code here that needs to be moved to
+ * LoginFormState.
+ */
+export class LoginManagerChild extends JSWindowActorChild {
+  /**
+   * WeakMap of the root element of a LoginForm to the DeferredTask to fill its fields.
+   *
+   * This is used to be able to throttle fills for a LoginForm since onDOMInputPasswordAdded gets
+   * dispatched for each password field added to a document but we only want to fill once per
+   * LoginForm when multiple fields are added at once.
+   *
+   * @type {WeakMap}
+   */
+  #deferredPasswordAddedTasksByRootElement = new WeakMap();
+
+  /**
+   * WeakMap of a document to the array of callbacks to execute when it becomes visible
+   *
+   * This is used to defer handling DOMFormHasPassword and onDOMInputPasswordAdded events when the
+   * containing document is hidden.
+   * When the document first becomes visible, any queued events will be handled as normal.
+   *
+   * @type {WeakMap}
+   */
+  #visibleTasksByDocument = new WeakMap();
+
+  /**
+   * Maps all DOM content documents in this content process, including those in
+   * frames, to the current state used by the Login Manager.
+   */
+  #loginFormStateByDocument = new WeakMap();
+
+  /**
+   * Set of fields where the user specifically requested password generation
+   * (from the context menu) even if we wouldn't offer it on this field by default.
+   */
+  #fieldsWithPasswordGenerationForcedOn = new WeakSet();
+
+  static forWindow(window) {
+    return window.windowGlobalChild?.getActor("LoginManager");
+  }
+
+  receiveMessage(msg) {
+    switch (msg.name) {
+      case "PasswordManager:fillForm": {
+        this.fillForm({
+          loginFormOrigin: msg.data.loginFormOrigin,
+          loginsFound: lazy.LoginHelper.vanillaObjectsToLogins(msg.data.logins),
+          recipes: msg.data.recipes,
+          inputElementIdentifier: msg.data.inputElementIdentifier,
+          originMatches: msg.data.originMatches,
+          style: msg.data.style,
+        });
+        break;
+      }
+      case "PasswordManager:useGeneratedPassword": {
+        this.#onUseGeneratedPassword(msg.data.inputElementIdentifier);
+        break;
+      }
+      case "PasswordManager:repopulateAutocompletePopup": {
+        this.repopulateAutocompletePopup();
+        break;
+      }
+      case "PasswordManager:formIsPending": {
+        return this.#visibleTasksByDocument.has(this.document);
+      }
+      case "PasswordManager:formProcessed": {
+        this.notifyObserversOfFormProcessed(msg.data.formid);
+        break;
+      }
+    }
+
+    return undefined;
+  }
+
+  #onUseGeneratedPassword(inputElementIdentifier) {
+    let inputElement = lazy.ContentDOMReference.resolve(inputElementIdentifier);
+    if (!inputElement) {
+      lazy.log("Could not resolve inputElementIdentifier to a living element.");
+      return;
+    }
+
+    if (inputElement != lazy.gFormFillService.focusedInput) {
+      lazy.log("Could not open popup on input that's no longer focused.");
+      return;
+    }
+
+    this.#fieldsWithPasswordGenerationForcedOn.add(inputElement);
+    this.repopulateAutocompletePopup();
+  }
+
+  repopulateAutocompletePopup() {
+    // Clear the cache of previous autocomplete results to show new options.
+    lazy.gFormFillService.QueryInterface(Ci.nsIAutoCompleteInput);
+    lazy.gFormFillService.controller.resetInternalState();
+    lazy.gFormFillService.showPopup();
+  }
+
+  shouldIgnoreLoginManagerEvent(event) {
+    let nodePrincipal = event.target.nodePrincipal;
+    // If we have a system or null principal then prevent any more password manager code from running and
+    // incorrectly using the document `location`. Also skip password manager for about: pages.
+    return (
+      nodePrincipal.isSystemPrincipal ||
+      nodePrincipal.isNullPrincipal ||
+      nodePrincipal.schemeIs("about")
+    );
+  }
+
+  registerDOMDocFetchSuccessEventListener(document) {
+    document.setNotifyFetchSuccess(true);
+    this.docShell.chromeEventHandler.addEventListener(
+      "DOMDocFetchSuccess",
+      this,
+      true
+    );
+  }
+
+  unregisterDOMDocFetchSuccessEventListener(document) {
+    document.setNotifyFetchSuccess(false);
+    this.docShell.chromeEventHandler.removeEventListener(
+      "DOMDocFetchSuccess",
+      this
+    );
+  }
+
+  handleEvent(event) {
+    if (
+      AppConstants.platform == "android" &&
+      Services.prefs.getBoolPref("reftest.remote", false)
+    ) {
+      // XXX known incompatibility between reftest harness and form-fill. Is this still needed?
+      return;
+    }
+
+    if (this.shouldIgnoreLoginManagerEvent(event)) {
+      return;
+    }
+
+    switch (event.type) {
+      case "DOMDocFetchSuccess": {
+        this.#onDOMDocFetchSuccess(event);
+        break;
+      }
+      case "DOMFormBeforeSubmit": {
+        this.#onDOMFormBeforeSubmit(event);
+        break;
+      }
+      case "DOMFormHasPassword": {
+        this.#onDOMFormHasPassword(event, this.document.defaultView);
+        let formLike = lazy.LoginFormFactory.createFromForm(
+          event.originalTarget
+        );
+        lazy.InsecurePasswordUtils.reportInsecurePasswords(formLike);
+        break;
+      }
+      case "DOMFormHasPossibleUsername": {
+        this.#onDOMFormHasPossibleUsername(event);
+        break;
+      }
+      case "DOMFormRemoved":
+      case "DOMInputPasswordRemoved": {
+        this.#onDOMFormRemoved(event);
+        break;
+      }
+      case "DOMInputPasswordAdded": {
+        this.#onDOMInputPasswordAdded(event, this.document.defaultView);
+        let formLike = lazy.LoginFormFactory.createFromField(
+          event.originalTarget
+        );
+        lazy.InsecurePasswordUtils.reportInsecurePasswords(formLike);
+        break;
+      }
+    }
+  }
+
+  notifyObserversOfFormProcessed(formid) {
+    Services.obs.notifyObservers(this, "passwordmgr-processed-form", formid);
+  }
+
+  /**
+   * Get relevant logins and recipes from the parent
+   *
+   * @param {HTMLFormElement} form - form to get login data for
+   * @param {Object} options
+   * @param {boolean} options.guid - guid of a login to retrieve
+   * @param {boolean} options.showPrimaryPassword - whether to show a primary password prompt
+   */
+  _getLoginDataFromParent(form, options) {
+    let actionOrigin = lazy.LoginHelper.getFormActionOrigin(form);
+    let messageData = { actionOrigin, options };
+    let resultPromise = this.sendQuery(
+      "PasswordManager:findLogins",
+      messageData
+    );
+    return resultPromise.then(result => {
+      return {
+        form,
+        importable: result.importable,
+        loginsFound: lazy.LoginHelper.vanillaObjectsToLogins(result.logins),
+        recipes: result.recipes,
+      };
+    });
+  }
+
+  setupProgressListener(window) {
+    if (!lazy.LoginHelper.formlessCaptureEnabled) {
+      return;
+    }
+
+    // Get the highest accessible docshell and attach the progress listener to that.
+    let docShell;
+    for (
+      let browsingContext = BrowsingContext.getFromWindow(window);
+      browsingContext?.docShell;
+      browsingContext = browsingContext.parent
+    ) {
+      docShell = browsingContext.docShell;
+    }
+
+    try {
+      let webProgress = docShell
+        .QueryInterface(Ci.nsIInterfaceRequestor)
+        .getInterface(Ci.nsIWebProgress);
+      webProgress.addProgressListener(
+        observer,
+        Ci.nsIWebProgress.NOTIFY_STATE_DOCUMENT |
+          Ci.nsIWebProgress.NOTIFY_LOCATION
+      );
+    } catch (ex) {
+      // Ignore NS_ERROR_FAILURE if the progress listener was already added
+    }
+  }
+
+  /**
+   * This method sets up form removal listener for form and password fields that
+   * users have interacted with.
+   */
+  #onDOMDocFetchSuccess(event) {
+    let document = event.target;
+    let docState = this.stateForDocument(document);
+    let weakModificationsRootElements =
+      ChromeUtils.nondeterministicGetWeakMapKeys(
+        docState.fieldModificationsByRootElement
+      );
+
+    lazy.log(
+      `modificationsByRootElement approx size: ${weakModificationsRootElements.length}.`
+    );
+    // Start to listen to form/password removed event after receiving a fetch/xhr
+    // complete event.
+    document.setNotifyFormOrPasswordRemoved(true);
+    this.docShell.chromeEventHandler.addEventListener(
+      "DOMFormRemoved",
+      this,
+      true
+    );
+    this.docShell.chromeEventHandler.addEventListener(
+      "DOMInputPasswordRemoved",
+      this,
+      true
+    );
+
+    for (let rootElement of weakModificationsRootElements) {
+      if (HTMLFormElement.isInstance(rootElement)) {
+        // If we create formLike when it is removed, we might not have the
+        // right elements at that point, so create formLike object now.
+        let formLike = lazy.LoginFormFactory.createFromForm(rootElement);
+        docState.formLikeByObservedNode.set(rootElement, formLike);
+      }
+    }
+
+    let weakFormlessModifiedPasswordFields =
+      ChromeUtils.nondeterministicGetWeakSetKeys(
+        docState.formlessModifiedPasswordFields
+      );
+
+    lazy.log(
+      `formlessModifiedPasswordFields approx size: ${weakFormlessModifiedPasswordFields.length}.`
+    );
+    for (let passwordField of weakFormlessModifiedPasswordFields) {
+      let formLike = lazy.LoginFormFactory.createFromField(passwordField);
+      // force elements lazy getter being called.
+      if (formLike.elements.length) {
+        docState.formLikeByObservedNode.set(passwordField, formLike);
+      }
+    }
+
+    // Observers have been set up, remove the listener.
+    this.unregisterDOMDocFetchSuccessEventListener(document);
+  }
+
+  /*
+   * Trigger capture when a form/formless password is removed from DOM.
+   * This method is used to capture logins for cases where form submit events
+   * are not used.
+   *
+   * The heuristic works as follow:
+   * 1. Set up 'DOMDocFetchSuccess' event listener when users have interacted
+   *    with a form (by calling setNotifyFetchSuccess)
+   * 2. After receiving `DOMDocFetchSuccess`, set up form removal event listener
+   *    (see onDOMDocFetchSuccess)
+   * 3. When a form is removed, onDOMFormRemoved triggers the login capture
+   *    code.
+   */
+  #onDOMFormRemoved(event) {
+    let document = event.composedTarget.ownerDocument;
+    let docState = this.stateForDocument(document);
+    let formLike = docState.formLikeByObservedNode.get(event.target);
+    if (!formLike) {
+      return;
+    }
+
+    lazy.log("Form is removed.");
+    this._onFormSubmit(formLike, SUBMIT_FORM_IS_REMOVED);
+
+    docState.formLikeByObservedNode.delete(event.target);
+    let weakObserveredNodes = ChromeUtils.nondeterministicGetWeakMapKeys(
+      docState.formLikeByObservedNode
+    );
+
+    if (!weakObserveredNodes.length) {
+      document.setNotifyFormOrPasswordRemoved(false);
+      this.docShell.chromeEventHandler.removeEventListener(
+        "DOMFormRemoved",
+        this
+      );
+      this.docShell.chromeEventHandler.removeEventListener(
+        "DOMInputPasswordRemoved",
+        this
+      );
+    }
+  }
+
+  #onDOMFormBeforeSubmit(event) {
+    if (!event.isTrusted) {
+      return;
+    }
+
+    // We're invoked before the content's |submit| event handlers, so we
+    // can grab form data before it might be modified (see bug 257781).
+    let formLike = lazy.LoginFormFactory.createFromForm(event.target);
+    this._onFormSubmit(formLike, SUBMIT_FORM_SUBMIT);
+  }
+
+  onDocumentVisibilityChange(event) {
+    if (!event.isTrusted) {
+      return;
+    }
+    let document = event.target;
+    let onVisibleTasks = this.#visibleTasksByDocument.get(document);
+    if (!onVisibleTasks) {
+      return;
+    }
+    for (let task of onVisibleTasks) {
+      lazy.log("onDocumentVisibilityChange: executing queued task.");
+      task();
+    }
+    this.#visibleTasksByDocument.delete(document);
+  }
+
+  _deferHandlingEventUntilDocumentVisible(event, document, fn) {
+    lazy.log(
+      `Defer handling event, document.visibilityState: ${document.visibilityState}, defer handling ${event.type}.`
+    );
+    let onVisibleTasks = this.#visibleTasksByDocument.get(document);
+    if (!onVisibleTasks) {
+      lazy.log(
+        "Defer handling first queued event and register the visibilitychange handler."
+      );
+      onVisibleTasks = [];
+      this.#visibleTasksByDocument.set(document, onVisibleTasks);
+      document.addEventListener(
+        "visibilitychange",
+        event => {
+          this.onDocumentVisibilityChange(event);
+        },
+        { once: true }
+      );
+    }
+    onVisibleTasks.push(fn);
+  }
+
+  #getIsPrimaryPasswordSet() {
+    return Services.cpmm.sharedData.get("isPrimaryPasswordSet");
+  }
+
+  #onDOMFormHasPassword(event, window) {
+    if (!event.isTrusted) {
+      return;
+    }
+
+    this.setupProgressListener(window);
+
+    const isPrimaryPasswordSet = this.#getIsPrimaryPasswordSet();
+    let document = event.target.ownerDocument;
+
+    // don't attempt to defer handling when a primary password is set
+    // Showing the MP modal as soon as possible minimizes its interference with tab interactions
+    // See bug 1539091 and bug 1538460.
+    lazy.log(
+      `#onDOMFormHasPassword: visibilityState: ${document.visibilityState}, isPrimaryPasswordSet: ${isPrimaryPasswordSet}.`
+    );
+
+    if (document.visibilityState == "visible" || isPrimaryPasswordSet) {
+      this._processDOMFormHasPasswordEvent(event);
+    } else {
+      // wait until the document becomes visible before handling this event
+      this._deferHandlingEventUntilDocumentVisible(event, document, () => {
+        this._processDOMFormHasPasswordEvent(event);
+      });
+    }
+  }
+
+  _processDOMFormHasPasswordEvent(event) {
+    let form = event.target;
+    let formLike = lazy.LoginFormFactory.createFromForm(form);
+    this._fetchLoginsFromParentAndFillForm(formLike);
+  }
+
+  #onDOMFormHasPossibleUsername(event) {
+    if (!event.isTrusted) {
+      return;
+    }
+    const isPrimaryPasswordSet = this.#getIsPrimaryPasswordSet();
+    let document = event.target.ownerDocument;
+
+    lazy.log(
+      `#onDOMFormHasPossibleUsername: visibilityState: ${document.visibilityState}, isPrimaryPasswordSet: ${isPrimaryPasswordSet}.`
+    );
+
+    // For simplicity, the result of the telemetry is stacked. This means if a
+    // document receives two `DOMFormHasPossibleEvent`, we add one counter to both
+    // bucket 1 & 2.
+    let docState = this.stateForDocument(document);
+    Services.telemetry
+      .getHistogramById("PWMGR_NUM_FORM_HAS_POSSIBLE_USERNAME_EVENT_PER_DOC")
+      .add(++docState.numFormHasPossibleUsernameEvent);
+
+    // Infer whether a form is a username-only form is expensive, so we restrict the
+    // number of form looked up per document.
+    if (
+      docState.numFormHasPossibleUsernameEvent >
+      lazy.LoginHelper.usernameOnlyFormLookupThreshold
+    ) {
+      return;
+    }
+
+    if (document.visibilityState == "visible" || isPrimaryPasswordSet) {
+      this._processDOMFormHasPossibleUsernameEvent(event);
+    } else {
+      // wait until the document becomes visible before handling this event
+      this._deferHandlingEventUntilDocumentVisible(event, document, () => {
+        this._processDOMFormHasPossibleUsernameEvent(event);
+      });
+    }
+  }
+
+  _processDOMFormHasPossibleUsernameEvent(event) {
+    let form = event.target;
+    let formLike = lazy.LoginFormFactory.createFromForm(form);
+
+    // If the form contains a passoword field, `getUsernameFieldFromUsernameOnlyForm` returns
+    // null, so we don't trigger autofill for those forms here. In this function,
+    // we only care about username-only forms. For forms contain a password, they'll be handled
+    // in onDOMFormHasPassword.
+
+    // We specifically set the recipe to empty here to avoid loading site recipes during page loads.
+    // This is okay because if we end up finding a username-only form that should be ignore by
+    // the site recipe, the form will be skipped while autofilling later.
+    let docState = this.stateForDocument(form.ownerDocument);
+    let usernameField = docState.getUsernameFieldFromUsernameOnlyForm(form, {});
+    if (usernameField) {
+      // Autofill the username-only form.
+      lazy.log("A username-only form is found.");
+      this._fetchLoginsFromParentAndFillForm(formLike);
+    }
+
+    Services.telemetry
+      .getHistogramById("PWMGR_IS_USERNAME_ONLY_FORM")
+      .add(!!usernameField);
+  }
+
+  #onDOMInputPasswordAdded(event, window) {
+    if (!event.isTrusted) {
+      return;
+    }
+
+    this.setupProgressListener(window);
+
+    let pwField = event.originalTarget;
+    if (pwField.form) {
+      // Fill is handled by onDOMFormHasPassword which is already throttled.
+      return;
+    }
+
+    let document = pwField.ownerDocument;
+    const isPrimaryPasswordSet = this.#getIsPrimaryPasswordSet();
+    lazy.log(
+      `#onDOMInputPasswordAdded, visibilityState: ${document.visibilityState}, isPrimaryPasswordSet: ${isPrimaryPasswordSet}.`
+    );
+
+    // don't attempt to defer handling when a primary password is set
+    // Showing the MP modal as soon as possible minimizes its interference with tab interactions
+    // See bug 1539091 and bug 1538460.
+    if (document.visibilityState == "visible" || isPrimaryPasswordSet) {
+      this._processDOMInputPasswordAddedEvent(event);
+    } else {
+      // wait until the document becomes visible before handling this event
+      this._deferHandlingEventUntilDocumentVisible(event, document, () => {
+        this._processDOMInputPasswordAddedEvent(event);
+      });
+    }
+  }
+
+  _processDOMInputPasswordAddedEvent(event) {
+    let pwField = event.originalTarget;
+    let formLike = lazy.LoginFormFactory.createFromField(pwField);
+
+    let deferredTask = this.#deferredPasswordAddedTasksByRootElement.get(
+      formLike.rootElement
+    );
+    if (!deferredTask) {
+      lazy.log(
+        "Creating a DeferredTask to call _fetchLoginsFromParentAndFillForm soon."
+      );
+      lazy.LoginFormFactory.setForRootElement(formLike.rootElement, formLike);
+
+      deferredTask = new lazy.DeferredTask(
+        () => {
+          // Get the updated LoginForm instead of the one at the time of creating the DeferredTask via
+          // a closure since it could be stale since LoginForm.elements isn't live.
+          let formLike2 = lazy.LoginFormFactory.getForRootElement(
+            formLike.rootElement
+          );
+          lazy.log("Running deferred processing of onDOMInputPasswordAdded.");
+          this.#deferredPasswordAddedTasksByRootElement.delete(
+            formLike2.rootElement
+          );
+          this._fetchLoginsFromParentAndFillForm(formLike2);
+        },
+        PASSWORD_INPUT_ADDED_COALESCING_THRESHOLD_MS,
+        0
+      );
+
+      this.#deferredPasswordAddedTasksByRootElement.set(
+        formLike.rootElement,
+        deferredTask
+      );
+    }
+
+    let window = pwField.ownerGlobal;
+    if (deferredTask.isArmed) {
+      lazy.log("DeferredTask is already armed so just updating the LoginForm.");
+      // We update the LoginForm so it (most important .elements) is fresh when the task eventually
+      // runs since changes to the elements could affect our field heuristics.
+      lazy.LoginFormFactory.setForRootElement(formLike.rootElement, formLike);
+    } else if (
+      ["interactive", "complete"].includes(window.document.readyState)
+    ) {
+      lazy.log(
+        "Arming the DeferredTask we just created since document.readyState == 'interactive' or 'complete'."
+      );
+      deferredTask.arm();
+    } else {
+      window.addEventListener(
+        "DOMContentLoaded",
+        function () {
+          lazy.log(
+            "Arming the onDOMInputPasswordAdded DeferredTask due to DOMContentLoaded."
+          );
+          deferredTask.arm();
+        },
+        { once: true }
+      );
+    }
+  }
+
+  /**
+   * Fetch logins from the parent for a given form and then attempt to fill it.
+   *
+   * @param {LoginForm} form to fetch the logins for then try autofill.
+   */
+  _fetchLoginsFromParentAndFillForm(form) {
+    if (!lazy.LoginHelper.enabled) {
+      return;
+    }
+
+    // set up input event listeners so we know if the user has interacted with these fields
+    // * input: Listen for the field getting blanked (without blurring) or a paste
+    // * change: Listen for changes to the field filled with the generated password so we can preserve edits.
+    form.rootElement.addEventListener("input", observer, {
+      capture: true,
+      mozSystemGroup: true,
+    });
+    form.rootElement.addEventListener("change", observer, {
+      capture: true,
+      mozSystemGroup: true,
+    });
+
+    this._getLoginDataFromParent(form, { showPrimaryPassword: true })
+      .then(this.loginsFound.bind(this))
+      .catch(console.error);
+  }
+
+  isPasswordGenerationForcedOn(passwordField) {
+    return this.#fieldsWithPasswordGenerationForcedOn.has(passwordField);
+  }
+
+  /**
+   * Retrieves a reference to the state object associated with the given
+   * document. This is initialized to an object with default values.
+   */
+  stateForDocument(document) {
+    let loginFormState = this.#loginFormStateByDocument.get(document);
+    if (!loginFormState) {
+      loginFormState = new LoginFormState();
+      this.#loginFormStateByDocument.set(document, loginFormState);
+    }
+    return loginFormState;
+  }
+
+  /**
+   * Perform a password fill upon user request coming from the parent process.
+   * The fill will be in the form previously identified during page navigation.
+   *
+   * @param An object with the following properties:
+   *        {
+   *          loginFormOrigin:
+   *            String with the origin for which the login UI was displayed.
+   *            This must match the origin of the form used for the fill.
+   *          loginsFound:
+   *            Array containing the login to fill. While other messages may
+   *            have more logins, for this use case this is expected to have
+   *            exactly one element. The origin of the login may be different
+   *            from the origin of the form used for the fill.
+   *          recipes:
+   *            Fill recipes transmitted together with the original message.
+   *          inputElementIdentifier:
+   *            An identifier generated for the input element via ContentDOMReference.
+   *          originMatches:
+   *            True if the origin of the form matches the page URI.
+   *        }
+   */
+  fillForm({
+    loginFormOrigin,
+    loginsFound,
+    recipes,
+    inputElementIdentifier,
+    originMatches,
+    style,
+  }) {
+    if (!inputElementIdentifier) {
+      lazy.log("No input element specified.");
+      return;
+    }
+
+    let inputElement = lazy.ContentDOMReference.resolve(inputElementIdentifier);
+    if (!inputElement) {
+      lazy.log("Could not resolve inputElementIdentifier to a living element.");
+      return;
+    }
+
+    if (!originMatches) {
+      if (
+        lazy.LoginHelper.getLoginOrigin(
+          inputElement.ownerDocument.documentURI
+        ) != loginFormOrigin
+      ) {
+        lazy.log(
+          "The requested origin doesn't match the one from the",
+          "document. This may mean we navigated to a document from a different",
+          "site before we had a chance to indicate this change in the user",
+          "interface."
+        );
+        return;
+      }
+    }
+
+    let clobberUsername = true;
+    let form = lazy.LoginFormFactory.createFromField(inputElement);
+    if (inputElement.hasBeenTypePassword) {
+      clobberUsername = false;
+    }
+
+    this._fillForm(form, loginsFound, recipes, {
+      inputElement,
+      autofillForm: true,
+      clobberUsername,
+      clobberPassword: true,
+      userTriggered: true,
+      style,
+    });
+  }
+
+  loginsFound({ form, importable, loginsFound, recipes }) {
+    let doc = form.ownerDocument;
+    let autofillForm =
+      lazy.LoginHelper.autofillForms &&
+      !PrivateBrowsingUtils.isContentWindowPrivate(doc.defaultView);
+
+    let formOrigin = lazy.LoginHelper.getLoginOrigin(doc.documentURI);
+    lazy.LoginRecipesContent.cacheRecipes(formOrigin, doc.defaultView, recipes);
+
+    this._fillForm(form, loginsFound, recipes, { autofillForm, importable });
+  }
+
+  /**
+   * A username or password was autocompleted into a field.
+   */
+  onFieldAutoComplete(acInputField, loginGUID) {
+    if (!lazy.LoginHelper.enabled) {
+      return;
+    }
+
+    // This is probably a bit over-conservatative.
+    if (!Document.isInstance(acInputField.ownerDocument)) {
+      return;
+    }
+
+    if (!lazy.LoginFormFactory.createFromField(acInputField)) {
+      return;
+    }
+
+    if (lazy.LoginHelper.isUsernameFieldType(acInputField)) {
+      this.onUsernameAutocompleted(acInputField, loginGUID);
+    } else if (acInputField.hasBeenTypePassword) {
+      // Ensure the field gets re-masked and edits don't overwrite the generated
+      // password in case a generated password was filled into it previously.
+      const docState = this.stateForDocument(acInputField.ownerDocument);
+      docState._stopTreatingAsGeneratedPasswordField(acInputField);
+      LoginFormState._highlightFilledField(acInputField);
+    }
+  }
+
+  /**
+   * A username field was filled or tabbed away from so try fill in the
+   * associated password in the password field.
+   */
+  onUsernameAutocompleted(acInputField, loginGUID = null) {
+    lazy.log(`Autocompleting input field with name: ${acInputField.name}`);
+
+    let acForm = lazy.LoginFormFactory.createFromField(acInputField);
+    let doc = acForm.ownerDocument;
+    let formOrigin = lazy.LoginHelper.getLoginOrigin(doc.documentURI);
+    let recipes = lazy.LoginRecipesContent.getRecipes(
+      formOrigin,
+      doc.defaultView
+    );
+
+    // Make sure the username field fillForm will use is the
+    // same field as the autocomplete was activated on.
+    const docState = this.stateForDocument(acInputField.ownerDocument);
+    let { usernameField, newPasswordField: passwordField } =
+      docState._getFormFields(acForm, false, recipes);
+    if (usernameField == acInputField) {
+      // Fill the form when a password field is present.
+      if (passwordField) {
+        this._getLoginDataFromParent(acForm, {
+          guid: loginGUID,
+          showPrimaryPassword: false,
+        })
+          .then(({ form, loginsFound, recipes }) => {
+            if (!loginGUID) {
+              // not an explicit autocomplete menu selection, filter for exact matches only
+              loginsFound = this._filterForExactFormOriginLogins(
+                loginsFound,
+                acForm
+              );
+              // filter the list for exact matches with the username
+              // NOTE: this could be an empty string which is a valid username
+              let searchString = usernameField.value.toLowerCase();
+              loginsFound = loginsFound.filter(
+                l => l.username.toLowerCase() == searchString
+              );
+            }
+
+            this._fillForm(form, loginsFound, recipes, {
+              autofillForm: true,
+              clobberPassword: true,
+              userTriggered: true,
+            });
+          })
+          .catch(console.error);
+        // Use `loginGUID !== null` to distinguish whether this is called when the
+        // field is filled or tabbed away from. For the latter, don't highlight the field.
+      } else if (loginGUID !== null) {
+        LoginFormState._highlightFilledField(usernameField);
+      }
+    } else {
+      // Ignore the event, it's for some input we don't care about.
+    }
+  }
+
+  /**
+   * @return true if the page requests autocomplete be disabled for the
+   *              specified element.
+   */
+  _isAutocompleteDisabled(element) {
+    return element?.autocomplete == "off";
+  }
+
+  /**
+   * Fill a page that was restored from bfcache since we wouldn't receive
+   * DOMInputPasswordAdded or DOMFormHasPassword events for it.
+   * @param {Document} aDocument that was restored from bfcache.
+   */
+  _onDocumentRestored(aDocument) {
+    let rootElsWeakSet =
+      lazy.LoginFormFactory.getRootElementsWeakSetForDocument(aDocument);
+    let weakLoginFormRootElements =
+      ChromeUtils.nondeterministicGetWeakSetKeys(rootElsWeakSet);
+
+    lazy.log(
+      `loginFormRootElements approx size: ${weakLoginFormRootElements.length}.`
+    );
+
+    for (let formRoot of weakLoginFormRootElements) {
+      if (!formRoot.isConnected) {
+        continue;
+      }
+
+      let formLike = lazy.LoginFormFactory.getForRootElement(formRoot);
+      this._fetchLoginsFromParentAndFillForm(formLike);
+    }
+  }
+
+  /**
+   * Trigger capture on any relevant FormLikes due to a navigation alone (not
+   * necessarily due to an actual form submission). This method is used to
+   * capture logins for cases where form submit events are not used.
+   *
+   * To avoid multiple notifications for the same LoginForm, this currently
+   * avoids capturing when dealing with a real <form> which are ideally already
+   * using a submit event.
+   *
+   * @param {Document} document being navigated
+   */
+  _onNavigation(aDocument) {
+    let rootElsWeakSet =
+      lazy.LoginFormFactory.getRootElementsWeakSetForDocument(aDocument);
+    let weakLoginFormRootElements =
+      ChromeUtils.nondeterministicGetWeakSetKeys(rootElsWeakSet);
+
+    lazy.log(`root elements approx size: ${weakLoginFormRootElements.length}`);
+
+    for (let formRoot of weakLoginFormRootElements) {
+      if (!formRoot.isConnected) {
+        continue;
+      }
+
+      let formLike = lazy.LoginFormFactory.getForRootElement(formRoot);
+      this._onFormSubmit(formLike, SUBMIT_PAGE_NAVIGATION);
+    }
+  }
+
+  /**
+   * Called by our observer when notified of a form submission.
+   * [Note that this happens before any DOM onsubmit handlers are invoked.]
+   * Looks for a password change in the submitted form, so we can update
+   * our stored password.
+   *
+   * @param {LoginForm} form
+   */
+  _onFormSubmit(form, reason) {
+    lazy.log("Detected form submission.");
+
+    this._maybeSendFormInteractionMessage(
+      form,
+      "PasswordManager:ShowDoorhanger",
+      {
+        targetField: null,
+        isSubmission: true,
+        // When this is trigger by inferring from form removal, the form is not
+        // connected anymore, skip checking isConnected in this case.
+        ignoreConnect: reason == SUBMIT_FORM_IS_REMOVED,
+      }
+    );
+  }
+
+  /**
+   * Extracts and validates information from a form-like element on the page.  If validation is
+   * successful, sends a message to the parent process requesting that it show a dialog.
+   *
+   * The validation works are divided into two parts:
+   * 1. Whether this is a valid form with a password (validate in this function)
+   * 2. Whether the password manager decides to send interaction message for this form
+   *    (validate in _maybeSendFormInteractionMessageContinue)
+   *
+   * When the function is triggered by a form submission event, and the form is valid (pass #1),
+   * We still send the message to the parent even the validation of #2 fails. This is because
+   * there might be someone who is interested in form submission events regardless of whether
+   * the password manager decides to show the doorhanger or not.
+   *
+   * @param {LoginForm} form
+   * @param {string} messageName used to categorize the type of message sent to the parent process.
+   * @param {Element?} options.targetField
+   * @param {boolean} options.isSubmission if true, this function call was prompted by a form submission.
+   * @param {boolean?} options.triggeredByFillingGenerated whether or not this call was triggered by a
+   *        generated password being filled into a form-like element.
+   * @param {boolean?} options.ignoreConnect Whether to ignore isConnected attribute of a element.
+   *
+   * @returns {Boolean} whether the message is sent to the parent process.
+   */
+  _maybeSendFormInteractionMessage(
+    form,
+    messageName,
+    { targetField, isSubmission, triggeredByFillingGenerated, ignoreConnect }
+  ) {
+    let logMessagePrefix = isSubmission
+      ? LOG_MESSAGE_FORM_SUBMISSION
+      : LOG_MESSAGE_FIELD_EDIT;
+    let doc = form.ownerDocument;
+    let win = doc.defaultView;
+    let passwordField = null;
+    if (targetField?.hasBeenTypePassword) {
+      passwordField = targetField;
+    }
+
+    let origin = lazy.LoginHelper.getLoginOrigin(doc.documentURI);
+    if (!origin) {
+      lazy.log(`${logMessagePrefix} ignored -- invalid origin.`);
+      return;
+    }
+
+    // Get the appropriate fields from the form.
+    let recipes = lazy.LoginRecipesContent.getRecipes(origin, win);
+    const docState = this.stateForDocument(form.ownerDocument);
+    let fields = {
+      targetField,
+      ...docState._getFormFields(form, true, recipes, { ignoreConnect }),
+    };
+
+    if (fields.usernameField) {
+      lazy.gFormFillService.markAsLoginManagerField(fields.usernameField);
+    }
+
+    // It's possible the field triggering this message isn't one of those found by _getFormFields' heuristics
+    if (
+      passwordField &&
+      passwordField != fields.newPasswordField &&
+      passwordField != fields.oldPasswordField &&
+      passwordField != fields.confirmPasswordField
+    ) {
+      fields.newPasswordField = passwordField;
+    }
+
+    // Need at least 1 valid password field to do anything.
+    if (fields.newPasswordField == null) {
+      if (isSubmission && fields.usernameField) {
+        lazy.log(
+          "_onFormSubmit: username-only form. Record the username field but not sending prompt."
+        );
+        docState.mockUsernameOnlyField = {
+          name: fields.usernameField.name,
+          value: fields.usernameField.value,
+        };
+      }
+      return;
+    }
+
+    this._maybeSendFormInteractionMessageContinue(form, messageName, {
+      ...fields,
+      isSubmission,
+      triggeredByFillingGenerated,
+    });
+
+    if (isSubmission) {
+      // Notify `PasswordManager:onFormSubmit` as long as we detect submission event on a
+      // valid form with a password field.
+      this.sendAsyncMessage(
+        "PasswordManager:onFormSubmit",
+        {},
+        {
+          fields,
+          isSubmission,
+          triggeredByFillingGenerated,
+        }
+      );
+    }
+  }
+
+  /**
+   * Continues the works that are not done in _maybeSendFormInteractionMessage.
+   * See comments in _maybeSendFormInteractionMessage for more details.
+   */
+  _maybeSendFormInteractionMessageContinue(
+    form,
+    messageName,
+    {
+      targetField,
+      usernameField,
+      newPasswordField,
+      oldPasswordField,
+      confirmPasswordField,
+      isSubmission,
+      triggeredByFillingGenerated,
+    }
+  ) {
+    let logMessagePrefix = isSubmission
+      ? LOG_MESSAGE_FORM_SUBMISSION
+      : LOG_MESSAGE_FIELD_EDIT;
+    let doc = form.ownerDocument;
+    let win = doc.defaultView;
+    let detail = { messageSent: false };
+    try {
+      // when filling a generated password, we do still want to message the parent
+      if (
+        !triggeredByFillingGenerated &&
+        PrivateBrowsingUtils.isContentWindowPrivate(win) &&
+        !lazy.LoginHelper.privateBrowsingCaptureEnabled
+      ) {
+        // We won't do anything in private browsing mode anyway,
+        // so there's no need to perform further checks.
+        lazy.log(`${logMessagePrefix} ignored in private browsing mode.`);
+        return;
+      }
+
+      // If password saving is disabled globally, bail out now.
+      if (!lazy.LoginHelper.enabled) {
+        return;
+      }
+
+      let fullyMungedPattern = /^\*+$|^•+$|^\.+$/;
+      // Check `isSubmission` to allow munged passwords in dismissed by default doorhangers (since
+      // they are initiated by the user) in case this matches their actual password.
+      if (isSubmission && newPasswordField?.value.match(fullyMungedPattern)) {
+        lazy.log("New password looks munged. Not sending prompt.");
+        return;
+      }
+
+      // When the username field is empty, check whether we have found it previously from
+      // a username-only form, if yes, fill in its value.
+      // XXX This is not ideal, we only use the previous saved username field when the current
+      // form doesn't have one. This means if there is a username field found in the current
+      // form, we don't compare it to the saved one, which might be a better choice in some cases.
+      // The reason we are not doing it now is because we haven't found a real world example.
+      let docState = this.stateForDocument(doc);
+      if (!usernameField) {
+        if (docState.mockUsernameOnlyField) {
+          usernameField = docState.mockUsernameOnlyField;
+        }
+      }
+      if (usernameField?.value.match(/\.{3,}|\*{3,}|•{3,}/)) {
+        lazy.log(
+          `usernameField with name ${usernameField.name} looks munged, setting to null.`
+        );
+        usernameField = null;
+      }
+
+      // Check for autocomplete=off attribute. We don't use it to prevent
+      // autofilling (for existing logins), but won't save logins when it's
+      // present and the storeWhenAutocompleteOff pref is false.
+      // XXX spin out a bug that we don't update timeLastUsed in this case?
+      if (
+        (this._isAutocompleteDisabled(form) ||
+          this._isAutocompleteDisabled(usernameField) ||
+          this._isAutocompleteDisabled(newPasswordField) ||
+          this._isAutocompleteDisabled(oldPasswordField)) &&
+        !lazy.LoginHelper.storeWhenAutocompleteOff
+      ) {
+        lazy.log(`${logMessagePrefix} ignored -- autocomplete=off found.`);
+        return;
+      }
+
+      // Don't try to send DOM nodes over IPC.
+      let mockUsername = usernameField
+        ? { name: usernameField.name, value: usernameField.value }
+        : null;
+      let mockPassword = {
+        name: newPasswordField.name,
+        value: newPasswordField.value,
+      };
+      let mockOldPassword = oldPasswordField
+        ? { name: oldPasswordField.name, value: oldPasswordField.value }
+        : null;
+
+      let usernameValue = usernameField?.value;
+      // Dismiss prompt if the username field is a credit card number AND
+      // if the password field is a three digit number. Also dismiss prompt if
+      // the password is a credit card number and the password field has attribute
+      // autocomplete="cc-number".
+      let dismissedPrompt = !isSubmission;
+      let newPasswordFieldValue = newPasswordField.value;
+      if (
+        (!dismissedPrompt &&
+          CreditCard.isValidNumber(usernameValue) &&
+          newPasswordFieldValue.trim().match(/^[0-9]{3}$/)) ||
+        (CreditCard.isValidNumber(newPasswordFieldValue) &&
+          newPasswordField.getAutocompleteInfo().fieldName == "cc-number")
+      ) {
+        dismissedPrompt = true;
+      }
+
+      const fieldsModified = docState._formHasModifiedFields(form);
+      if (!fieldsModified && lazy.LoginHelper.userInputRequiredToCapture) {
+        if (targetField) {
+          throw new Error("No user input on targetField");
+        }
+        // we know no fields in this form had user modifications, so don't prompt
+        lazy.log(
+          `${logMessagePrefix} ignored -- submitting values that are not changed by the user.`
+        );
+        return;
+      }
+
+      if (
+        docState.compareAndUpdatePreviouslySentValues(
+          form.rootElement,
+          usernameValue,
+          newPasswordField.value,
+          dismissedPrompt,
+          triggeredByFillingGenerated
+        )
+      ) {
+        lazy.log(
+          `${logMessagePrefix} ignored -- already submitted with the same username and password.`
+        );
+        return;
+      }
+
+      let { login: autoFilledLogin } =
+        docState.fillsByRootElement.get(form.rootElement) || {};
+      let browsingContextId = win.windowGlobalChild.browsingContext.id;
+      let formActionOrigin = lazy.LoginHelper.getFormActionOrigin(form);
+
+      detail = {
+        browsingContextId,
+        formActionOrigin,
+        autoFilledLoginGuid: autoFilledLogin && autoFilledLogin.guid,
+        usernameField: mockUsername,
+        newPasswordField: mockPassword,
+        oldPasswordField: mockOldPassword,
+        dismissedPrompt,
+        triggeredByFillingGenerated,
+        possibleValues: {
+          usernames: docState.possibleUsernames,
+          passwords: docState.possiblePasswords,
+        },
+        messageSent: true,
+      };
+
+      if (messageName == "PasswordManager:ShowDoorhanger") {
+        docState.captureLoginTimeStamp = doc.lastUserGestureTimeStamp;
+      }
+      this.sendAsyncMessage(messageName, detail);
+    } catch (ex) {
+      console.error(ex);
+      throw ex;
+    } finally {
+      detail.form = form;
+      const evt = new CustomEvent(messageName, { detail });
+      win.windowRoot.dispatchEvent(evt);
+    }
+  }
+
+  /**
+   * Heuristic for whether or not we should consider [field]s value to be 'new' (as opposed to
+   * 'changed') after applying [event].
+   *
+   * @param {HTMLInputElement} event.target input element being changed.
+   * @param {string?} event.data new value being input into the field.
+   *
+   * @returns {boolean}
+   */
+  _doesEventClearPrevFieldValue({ target, data, inputType }) {
+    return (
+      !target.value ||
+      // We check inputType here as a proxy for the previous field value.
+      // If the previous field value was empty, e.g. automatically filling
+      // a confirm password field when a new password field is filled with
+      // a generated password, there's nothing to replace.
+      // We may be able to use the "beforeinput" event instead when that
+      // ships (Bug 1609291).
+      (data && data == target.value && inputType !== "insertReplacementText")
+    );
+  }
+
+  /**
+   * The password field has been filled with a generated password, ensure the
+   * field is handled accordingly.
+   * @param {HTMLInputElement} passwordField
+   */
+  _filledWithGeneratedPassword(passwordField) {
+    LoginFormState._highlightFilledField(passwordField);
+    this._passwordEditedOrGenerated(passwordField, {
+      triggeredByFillingGenerated: true,
+    });
+    let docState = this.stateForDocument(passwordField.ownerDocument);
+    docState.fillConfirmFieldWithGeneratedPassword(passwordField);
+  }
+
+  /**
+   * Notify the parent that we are ignoring the password edit
+   * so that tests can listen for this as opposed to waiting for
+   * nothing to happen.
+   */
+  _ignorePasswordEdit() {
+    if (Cu.isInAutomation) {
+      this.sendAsyncMessage("PasswordManager:onIgnorePasswordEdit", {});
+    }
+  }
+  /**
+   * Notify the parent that a generated password was filled into a field or
+   * edited so that it can potentially be saved.
+   * @param {HTMLInputElement} passwordField
+   */
+  _passwordEditedOrGenerated(
+    passwordField,
+    { triggeredByFillingGenerated = false } = {}
+  ) {
+    lazy.log(
+      `Password field with name ${passwordField.name} was filled or edited.`
+    );
+
+    if (!lazy.LoginHelper.enabled && triggeredByFillingGenerated) {
+      throw new Error(
+        "A generated password was filled while the password manager was disabled."
+      );
+    }
+
+    let loginForm = lazy.LoginFormFactory.createFromField(passwordField);
+
+    if (triggeredByFillingGenerated) {
+      LoginFormState._highlightFilledField(passwordField);
+      let docState = this.stateForDocument(passwordField.ownerDocument);
+      docState._treatAsGeneratedPasswordField(passwordField);
+
+      // Once the generated password was filled we no longer want to autocomplete
+      // saved logins into a non-empty password field (see LoginAutoComplete.startSearch)
+      // because it is confusing.
+      this.#fieldsWithPasswordGenerationForcedOn.delete(passwordField);
+    }
+
+    this._maybeSendFormInteractionMessage(
+      loginForm,
+      "PasswordManager:onPasswordEditedOrGenerated",
+      {
+        targetField: passwordField,
+        isSubmission: false,
+        triggeredByFillingGenerated,
+      }
+    );
+  }
+
+  /**
+   * Filter logins for exact origin/formActionOrigin and dedupe on usernamematche
+   * @param {nsILoginInfo[]} logins an array of nsILoginInfo that could be
+   *        used for the form, including ones with a different form action origin
+   *        which are only used when the fill is userTriggered
+   * @param {LoginForm} form
+   */
+  _filterForExactFormOriginLogins(logins, form) {
+    let loginOrigin = lazy.LoginHelper.getLoginOrigin(
+      form.ownerDocument.documentURI
+    );
+    let formActionOrigin = lazy.LoginHelper.getFormActionOrigin(form);
+    logins = logins.filter(l => {
+      let formActionMatches = lazy.LoginHelper.isOriginMatching(
+        l.formActionOrigin,
+        formActionOrigin,
+        {
+          schemeUpgrades: lazy.LoginHelper.schemeUpgrades,
+          acceptWildcardMatch: true,
+          acceptDifferentSubdomains: true,
+        }
+      );
+      let formOriginMatches = lazy.LoginHelper.isOriginMatching(
+        l.origin,
+        loginOrigin,
+        {
+          schemeUpgrades: lazy.LoginHelper.schemeUpgrades,
+          acceptWildcardMatch: true,
+          acceptDifferentSubdomains: false,
+        }
+      );
+      return formActionMatches && formOriginMatches;
+    });
+
+    // Since the logins are already filtered now to only match the origin and formAction,
+    // dedupe to just the username since remaining logins may have different schemes.
+    logins = lazy.LoginHelper.dedupeLogins(
+      logins,
+      ["username"],
+      ["scheme", "timePasswordChanged"],
+      loginOrigin,
+      formActionOrigin
+    );
+    return logins;
+  }
+
+  /**
+   * Attempt to find the username and password fields in a form, and fill them
+   * in using the provided logins and recipes.
+   *
+   * @param {LoginForm} form
+   * @param {nsILoginInfo[]} foundLogins an array of nsILoginInfo that could be
+   *        used for the form, including ones with a different form action origin
+   *        which are only used when the fill is userTriggered
+   * @param {Set} recipes a set of recipes that could be used to affect how the
+   *        form is filled
+   * @param {Object} [options = {}] a list of options for this method
+   * @param {HTMLInputElement} [options.inputElement = null] an optional target
+   *        input element we want to fill
+   * @param {bool} [options.autofillForm = false] denotes if we should fill the
+   *        form in automatically
+   * @param {bool} [options.clobberUsername = false] controls if an existing
+   *        username can be overwritten. If this is false and an inputElement
+   *        of type password is also passed, the username field will be ignored.
+   *        If this is false and no inputElement is passed, if the username
+   *        field value is not found in foundLogins, it will not fill the
+   *        password.
+   * @param {bool} [options.clobberPassword = false] controls if an existing
+   *        password value can be overwritten
+   * @param {bool} [options.userTriggered = false] an indication of whether
+   *        this filling was triggered by the user
+   */
+  // eslint-disable-next-line complexity
+  _fillForm(
+    form,
+    foundLogins,
+    recipes,
+    {
+      inputElement = null,
+      autofillForm = false,
+      importable = null,
+      clobberUsername = false,
+      clobberPassword = false,
+      userTriggered = false,
+      style = null,
+    } = {}
+  ) {
+    if (HTMLFormElement.isInstance(form)) {
+      throw new Error("_fillForm should only be called with LoginForm objects");
+    }
+
+    lazy.log(`Found ${form.elements.length} form elements.`);
+    // Will be set to one of AUTOFILL_RESULT in the `try` block.
+    let autofillResult;
+    const docState = this.stateForDocument(form.ownerDocument);
+
+    // Heuristically determine what the user/pass fields are
+    // We do this before checking to see if logins are stored,
+    // so that the user isn't prompted for a primary password
+    // without need.
+    let { usernameField, newPasswordField: passwordField } =
+      docState._getFormFields(form, false, recipes);
+
+    const passwordACFieldName = passwordField?.getAutocompleteInfo().fieldName;
+
+    let scenario;
+
+    if (usernameField) {
+      const isSignUpForm =
+        lazy.FormScenarios.detect({
+          input: usernameField,
+          formRoot: form.rootElement,
+        }).signUpForm ?? passwordACFieldName == "new-password";
+
+      if (isSignUpForm) {
+        scenario = new SignUpFormScenario(usernameField, passwordField);
+      }
+
+      if (scenario) {
+        docState.setScenario(form.rootElement, scenario);
+        lazy.gFormFillService.markAsLoginManagerField(usernameField);
+      }
+    }
+
+    try {
+      // Nothing to do if we have no matching (excluding form action
+      // checks) logins available, and there isn't a need to show
+      // the insecure form warning.
+      if (
+        !foundLogins.length &&
+        !(importable?.state === "import" && importable?.browsers) &&
+        lazy.InsecurePasswordUtils.isFormSecure(form)
+      ) {
+        // We don't log() here since this is a very common case.
+        autofillResult = AUTOFILL_RESULT.NO_SAVED_LOGINS;
+        return;
+      }
+
+      // If we have a password inputElement parameter and it's not
+      // the same as the one heuristically found, use the parameter
+      // one instead.
+      if (inputElement) {
+        if (inputElement.hasBeenTypePassword) {
+          passwordField = inputElement;
+          if (!clobberUsername) {
+            usernameField = null;
+          }
+        } else if (lazy.LoginHelper.isUsernameFieldType(inputElement)) {
+          usernameField = inputElement;
+        } else {
+          throw new Error("Unexpected input element type.");
+        }
+      }
+
+      // Need a valid password or username field to do anything.
+      if (passwordField == null && usernameField == null) {
+        lazy.log("Not filling form, no password and username field found.");
+        autofillResult = AUTOFILL_RESULT.NO_PASSWORD_FIELD;
+        return;
+      }
+
+      // Attach autocomplete stuff to the username field, if we have
+      // one. This is normally used to select from multiple accounts,
+      // but even with one account we should refill if the user edits.
+      // We would also need this attached to show the insecure login
+      // warning, regardless of saved login.
+      if (usernameField) {
+        lazy.gFormFillService.markAsLoginManagerField(usernameField);
+        usernameField.addEventListener("keydown", observer);
+      }
+
+      // If the password field is disabled or read-only, there's nothing to do.
+      if (passwordField?.disabled || passwordField?.readOnly) {
+        lazy.log("Not filling form, password field disabled or read-only.");
+        autofillResult = AUTOFILL_RESULT.PASSWORD_DISABLED_READONLY;
+        return;
+      }
+
+      if (
+        !userTriggered &&
+        !form.rootElement.ownerGlobal.windowGlobalChild.sameOriginWithTop
+      ) {
+        lazy.log("Not filling form; it is in a cross-origin subframe.");
+        autofillResult = AUTOFILL_RESULT.FORM_IN_CROSSORIGIN_SUBFRAME;
+        return;
+      }
+
+      if (!userTriggered) {
+        // Only autofill logins that match the form's action and origin. In the above code
+        // we have attached autocomplete for logins that don't match the form action.
+        foundLogins = this._filterForExactFormOriginLogins(foundLogins, form);
+      }
+
+      // Nothing to do if we have no matching logins available.
+      // Only insecure pages reach this block and logs the same
+      // telemetry flag.
+      if (!foundLogins.length) {
+        // We don't log() here since this is a very common case.
+        autofillResult = AUTOFILL_RESULT.NO_SAVED_LOGINS;
+        return;
+      }
+
+      // Prevent autofilling insecure forms.
+      if (
+        !userTriggered &&
+        !lazy.LoginHelper.insecureAutofill &&
+        !lazy.InsecurePasswordUtils.isFormSecure(form)
+      ) {
+        lazy.log("Not filling form since it's insecure.");
+        autofillResult = AUTOFILL_RESULT.INSECURE;
+        return;
+      }
+
+      // Discard logins which have username/password values that don't
+      // fit into the fields (as specified by the maxlength attribute).
+      // The user couldn't enter these values anyway, and it helps
+      // with sites that have an extra PIN to be entered (bug 391514)
+      let maxUsernameLen = Number.MAX_VALUE;
+      let maxPasswordLen = Number.MAX_VALUE;
+
+      // If attribute wasn't set, default is -1.
+      if (usernameField?.maxLength >= 0) {
+        maxUsernameLen = usernameField.maxLength;
+      }
+      if (passwordField?.maxLength >= 0) {
+        maxPasswordLen = passwordField.maxLength;
+      }
+
+      let logins = foundLogins.filter(function (l) {
+        let fit =
+          l.username.length <= maxUsernameLen &&
+          l.password.length <= maxPasswordLen;
+        if (!fit) {
+          lazy.log(`Ignored login: won't fit ${l.username.length}.`);
+        }
+
+        return fit;
+      }, this);
+
+      if (!logins.length) {
+        lazy.log("Form not filled, none of the logins fit in the field.");
+        autofillResult = AUTOFILL_RESULT.NO_LOGINS_FIT;
+        return;
+      }
+
+      if (passwordField) {
+        if (!userTriggered && passwordField.type != "password") {
+          // We don't want to autofill (without user interaction) into a field
+          // that's unmasked.
+          lazy.log(
+            "Not autofilling, password field isn't currently type=password."
+          );
+          autofillResult = AUTOFILL_RESULT.TYPE_NO_LONGER_PASSWORD;
+          return;
+        }
+
+        // If the password field has the autocomplete value of "new-password"
+        // and we're autofilling without user interaction, there's nothing to do.
+        if (!userTriggered && passwordACFieldName == "new-password") {
+          lazy.log(
+            "Not filling form, password field has the autocomplete new-password value."
+          );
+          autofillResult = AUTOFILL_RESULT.PASSWORD_AUTOCOMPLETE_NEW_PASSWORD;
+          return;
+        }
+
+        // Don't clobber an existing password.
+        if (passwordField.value && !clobberPassword) {
+          lazy.log("Form not filled, the password field was already filled.");
+          autofillResult = AUTOFILL_RESULT.EXISTING_PASSWORD;
+          return;
+        }
+      }
+
+      // Select a login to use for filling in the form.
+      let selectedLogin;
+      if (
+        !clobberUsername &&
+        usernameField &&
+        (usernameField.value ||
+          usernameField.disabled ||
+          usernameField.readOnly)
+      ) {
+        // If username was specified in the field, it's disabled or it's readOnly, only fill in the
+        // password if we find a matching login.
+        let username = usernameField.value.toLowerCase();
+
+        let matchingLogins = logins.filter(
+          l => l.username.toLowerCase() == username
+        );
+        if (!matchingLogins.length) {
+          lazy.log(
+            "Password not filled. None of the stored logins match the username already present."
+          );
+          autofillResult = AUTOFILL_RESULT.EXISTING_USERNAME;
+          return;
+        }
+
+        // If there are multiple, and one matches case, use it
+        for (let l of matchingLogins) {
+          if (l.username == usernameField.value) {
+            selectedLogin = l;
+          }
+        }
+        // Otherwise just use the first
+        if (!selectedLogin) {
+          selectedLogin = matchingLogins[0];
+        }
+      } else if (logins.length == 1) {
+        selectedLogin = logins[0];
+      } else {
+        // We have multiple logins. Handle a special case here, for sites
+        // which have a normal user+pass login *and* a password-only login
+        // (eg, a PIN). Prefer the login that matches the type of the form
+        // (user+pass or pass-only) when there's exactly one that matches.
+        let matchingLogins;
+        if (usernameField) {
+          matchingLogins = logins.filter(l => l.username);
+        } else {
+          matchingLogins = logins.filter(l => !l.username);
+        }
+
+        if (matchingLogins.length != 1) {
+          lazy.log("Multiple logins for form, so not filling any.");
+          autofillResult = AUTOFILL_RESULT.MULTIPLE_LOGINS;
+          return;
+        }
+
+        selectedLogin = matchingLogins[0];
+      }
+
+      // We will always have a selectedLogin at this point.
+
+      if (!autofillForm) {
+        lazy.log("autofillForms=false but form can be filled.");
+        autofillResult = AUTOFILL_RESULT.NO_AUTOFILL_FORMS;
+        return;
+      }
+
+      if (
+        !userTriggered &&
+        passwordACFieldName == "off" &&
+        !lazy.LoginHelper.autofillAutocompleteOff
+      ) {
+        lazy.log(
+          "Not autofilling the login because we're respecting autocomplete=off."
+        );
+        autofillResult = AUTOFILL_RESULT.AUTOCOMPLETE_OFF;
+        return;
+      }
+
+      // Fill the form
+
+      let willAutofill =
+        usernameField || passwordField.value != selectedLogin.password;
+      if (willAutofill) {
+        let autoFilledLogin = {
+          guid: selectedLogin.QueryInterface(Ci.nsILoginMetaInfo).guid,
+          username: selectedLogin.username,
+          usernameField: usernameField
+            ? Cu.getWeakReference(usernameField)
+            : null,
+          password: selectedLogin.password,
+          passwordField: passwordField
+            ? Cu.getWeakReference(passwordField)
+            : null,
+        };
+        // Ensure the state is updated before setUserInput is called.
+        lazy.log(
+          "Saving autoFilledLogin",
+          autoFilledLogin.guid,
+          "for",
+          form.rootElement
+        );
+        docState.fillsByRootElement.set(form.rootElement, {
+          login: autoFilledLogin,
+          userTriggered,
+        });
+      }
+      if (usernameField) {
+        // Don't modify the username field because the user wouldn't be able to change it either.
+        let disabledOrReadOnly =
+          usernameField.disabled || usernameField.readOnly;
+
+        if (selectedLogin.username && !disabledOrReadOnly) {
+          let userNameDiffers = selectedLogin.username != usernameField.value;
+          // Don't replace the username if it differs only in case, and the user triggered
+          // this autocomplete. We assume that if it was user-triggered the entered text
+          // is desired.
+          let userEnteredDifferentCase =
+            userTriggered &&
+            userNameDiffers &&
+            usernameField.value.toLowerCase() ==
+              selectedLogin.username.toLowerCase();
+
+          if (!userEnteredDifferentCase && userNameDiffers) {
+            usernameField.setUserInput(selectedLogin.username);
+          }
+          LoginFormState._highlightFilledField(usernameField);
+        }
+      }
+
+      if (passwordField) {
+        if (passwordField.value != selectedLogin.password) {
+          // Ensure the field gets re-masked in case a generated password was
+          // filled into it previously.
+          docState._stopTreatingAsGeneratedPasswordField(passwordField);
+
+          passwordField.setUserInput(selectedLogin.password);
+        }
+
+        LoginFormState._highlightFilledField(passwordField);
+      }
+
+      if (style === "generatedPassword") {
+        this._filledWithGeneratedPassword(passwordField);
+      }
+
+      lazy.log("_fillForm succeeded");
+      if (passwordField) {
+        autofillResult = AUTOFILL_RESULT.FILLED;
+      } else if (usernameField) {
+        autofillResult = AUTOFILL_RESULT.FILLED_USERNAME_ONLY_FORM;
+      }
+    } catch (ex) {
+      console.error(ex);
+      throw ex;
+    } finally {
+      if (!autofillResult) {
+        // eslint-disable-next-line no-unsafe-finally
+        throw new Error("_fillForm: autofillResult must be specified");
+      }
+
+      if (!userTriggered) {
+        // Ignore fills as a result of user action for this probe.
+
+        lazy.LoginManagerTelemetry.recordAutofillResult(autofillResult);
+
+        if (usernameField) {
+          let focusedElement = lazy.gFormFillService.focusedInput;
+          if (
+            usernameField == focusedElement &&
+            ![
+              AUTOFILL_RESULT.FILLED,
+              AUTOFILL_RESULT.FILLED_USERNAME_ONLY_FORM,
+            ].includes(autofillResult)
+          ) {
+            lazy.log(
+              "Opening username autocomplete popup since the form wasn't autofilled."
+            );
+            lazy.gFormFillService.showPopup();
+          }
+        }
+      }
+
+      if (usernameField) {
+        lazy.log("Attaching event listeners to usernameField.");
+        usernameField.addEventListener("focus", observer);
+        usernameField.addEventListener("mousedown", observer);
+      }
+
+      this.sendAsyncMessage("PasswordManager:formProcessed", {
+        formid: form.rootElement.id,
+        autofillResult,
+      });
+    }
+  }
+
+  getScenario(inputElement) {
+    const docState = this.stateForDocument(inputElement.ownerDocument);
+    return docState.getScenario(inputElement);
+  }
+}
diff --git a/toolkit/components/passwordmgr/LoginManagerContextMenu.sys.mjs b/toolkit/components/passwordmgr/LoginManagerContextMenu.sys.mjs
new file mode 100644
index 0000000000..fc87f5cf58
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginManagerContextMenu.sys.mjs
@@ -0,0 +1,238 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+});
+
+/**
+ * Password manager object for the browser contextual menu.
+ */
+export const LoginManagerContextMenu = {
+  /**
+   * Look for login items and add them to the contextual menu.
+   *
+   * @param {Object} inputElementIdentifier
+   *        An identifier generated for the input element via ContentDOMReference.
+   * @param {xul:browser} browser
+   *        The browser for the document the context menu was open on.
+   * @param {string} formOrigin
+   *        The origin of the document that the context menu was activated from.
+   *        This isn't the same as the browser's top-level document origin
+   *        when subframes are involved.
+   * @returns {DocumentFragment} a document fragment with all the login items.
+   */
+  addLoginsToMenu(inputElementIdentifier, browser, formOrigin) {
+    let foundLogins = this._findLogins(formOrigin);
+
+    if (!foundLogins.length) {
+      return null;
+    }
+
+    let fragment = browser.ownerDocument.createDocumentFragment();
+    let duplicateUsernames = this._findDuplicates(foundLogins);
+    for (let login of foundLogins) {
+      let item = fragment.ownerDocument.createXULElement("menuitem");
+
+      let username = login.username;
+      // If login is empty or duplicated we want to append a modification date to it.
+      if (!username || duplicateUsernames.has(username)) {
+        if (!username) {
+          username = this._getLocalizedString("noUsername");
+        }
+        let meta = login.QueryInterface(Ci.nsILoginMetaInfo);
+        let time = this.dateAndTimeFormatter.format(
+          new Date(meta.timePasswordChanged)
+        );
+        username = this._getLocalizedString("loginHostAge", [username, time]);
+      }
+      item.setAttribute("label", username);
+      item.setAttribute("class", "context-login-item");
+
+      // login is bound so we can keep the reference to each object.
+      item.addEventListener(
+        "command",
+        function (login, event) {
+          this._fillTargetField(
+            login,
+            inputElementIdentifier,
+            browser,
+            formOrigin
+          );
+        }.bind(this, login)
+      );
+
+      fragment.appendChild(item);
+    }
+
+    return fragment;
+  },
+
+  /**
+   * Undoes the work of addLoginsToMenu for the same menu.
+   *
+   * @param {Document}
+   *        The context menu owner document.
+   */
+  clearLoginsFromMenu(document) {
+    let loginItems = document.getElementsByClassName("context-login-item");
+    while (loginItems.item(0)) {
+      loginItems.item(0).remove();
+    }
+  },
+
+  /**
+   * Show the password autocomplete UI with the generation option forced to appear.
+   */
+  async useGeneratedPassword(inputElementIdentifier, documentURI, browser) {
+    let browsingContextId = inputElementIdentifier.browsingContextId;
+    let browsingContext = BrowsingContext.get(browsingContextId);
+    let actor = browsingContext.currentWindowGlobal.getActor("LoginManager");
+
+    actor.sendAsyncMessage("PasswordManager:useGeneratedPassword", {
+      inputElementIdentifier,
+    });
+  },
+
+  /**
+   * Find logins for the specified origin..
+   *
+   * @param {string} formOrigin
+   *        Origin of the logins we want to find that has be sanitized by `getLoginOrigin`.
+   *        This isn't the same as the browser's top-level document URI
+   *        when subframes are involved.
+   *
+   * @returns {nsILoginInfo[]} a login list
+   */
+  _findLogins(formOrigin) {
+    let searchParams = {
+      origin: formOrigin,
+      schemeUpgrades: lazy.LoginHelper.schemeUpgrades,
+    };
+    let logins = lazy.LoginHelper.searchLoginsWithObject(searchParams);
+    let resolveBy = ["scheme", "timePasswordChanged"];
+    logins = lazy.LoginHelper.dedupeLogins(
+      logins,
+      ["username", "password"],
+      resolveBy,
+      formOrigin
+    );
+
+    // Sort logins in alphabetical order and by date.
+    logins.sort((loginA, loginB) => {
+      // Sort alphabetically
+      let result = loginA.username.localeCompare(loginB.username);
+      if (result) {
+        // Forces empty logins to be at the end
+        if (!loginA.username) {
+          return 1;
+        }
+        if (!loginB.username) {
+          return -1;
+        }
+        return result;
+      }
+
+      // Same username logins are sorted by last change date
+      let metaA = loginA.QueryInterface(Ci.nsILoginMetaInfo);
+      let metaB = loginB.QueryInterface(Ci.nsILoginMetaInfo);
+      return metaB.timePasswordChanged - metaA.timePasswordChanged;
+    });
+
+    return logins;
+  },
+
+  /**
+   * Find duplicate usernames in a login list.
+   *
+   * @param {nsILoginInfo[]} loginList
+   *        A list of logins we want to look for duplicate usernames.
+   *
+   * @returns {Set} a set with the duplicate usernames.
+   */
+  _findDuplicates(loginList) {
+    let seen = new Set();
+    let duplicates = new Set();
+    for (let login of loginList) {
+      if (seen.has(login.username)) {
+        duplicates.add(login.username);
+      }
+      seen.add(login.username);
+    }
+    return duplicates;
+  },
+
+  /**
+   * @param {nsILoginInfo} login
+   *        The login we want to fill the form with.
+   * @param {Object} inputElementIdentifier
+   *        An identifier generated for the input element via ContentDOMReference.
+   * @param {xul:browser} browser
+   *        The target tab browser.
+   * @param {string} formOrigin
+   *        Origin of the document we're filling after sanitization via
+   *        `getLoginOrigin`.
+   *        This isn't the same as the browser's top-level
+   *        origin when subframes are involved.
+   */
+  _fillTargetField(login, inputElementIdentifier, browser, formOrigin) {
+    let browsingContextId = inputElementIdentifier.browsingContextId;
+    let browsingContext = BrowsingContext.get(browsingContextId);
+    if (!browsingContext) {
+      return;
+    }
+
+    let actor = browsingContext.currentWindowGlobal.getActor("LoginManager");
+    if (!actor) {
+      return;
+    }
+
+    actor
+      .fillForm({
+        browser,
+        inputElementIdentifier,
+        loginFormOrigin: formOrigin,
+        login,
+      })
+      .catch(console.error);
+  },
+
+  /**
+   * @param {string} key
+   *        The localized string key
+   * @param {string[]} formatArgs
+   *        An array of formatting argument string
+   *
+   * @returns {string} the localized string for the specified key,
+   *          formatted with arguments if required.
+   */
+  _getLocalizedString(key, formatArgs) {
+    if (formatArgs) {
+      return this._stringBundle.formatStringFromName(key, formatArgs);
+    }
+    return this._stringBundle.GetStringFromName(key);
+  },
+};
+
+ChromeUtils.defineLazyGetter(
+  LoginManagerContextMenu,
+  "_stringBundle",
+  function () {
+    return Services.strings.createBundle(
+      "chrome://passwordmgr/locale/passwordmgr.properties"
+    );
+  }
+);
+
+ChromeUtils.defineLazyGetter(
+  LoginManagerContextMenu,
+  "dateAndTimeFormatter",
+  function () {
+    return new Services.intl.DateTimeFormat(undefined, {
+      dateStyle: "medium",
+    });
+  }
+);
diff --git a/toolkit/components/passwordmgr/LoginManagerParent.sys.mjs b/toolkit/components/passwordmgr/LoginManagerParent.sys.mjs
new file mode 100644
index 0000000000..862ab6b846
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginManagerParent.sys.mjs
@@ -0,0 +1,1553 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import { FirefoxRelayTelemetry } from "resource://gre/modules/FirefoxRelayTelemetry.mjs";
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+
+const LoginInfo = new Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  Ci.nsILoginInfo,
+  "init"
+);
+
+const lazy = {};
+
+ChromeUtils.defineLazyGetter(lazy, "LoginRelatedRealmsParent", () => {
+  const { LoginRelatedRealmsParent } = ChromeUtils.importESModule(
+    "resource://gre/modules/LoginRelatedRealms.sys.mjs"
+  );
+  return new LoginRelatedRealmsParent();
+});
+
+ChromeUtils.defineLazyGetter(lazy, "PasswordRulesManager", () => {
+  const { PasswordRulesManagerParent } = ChromeUtils.importESModule(
+    "resource://gre/modules/PasswordRulesManager.sys.mjs"
+  );
+  return new PasswordRulesManagerParent();
+});
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  ChromeMigrationUtils: "resource:///modules/ChromeMigrationUtils.sys.mjs",
+  FirefoxRelay: "resource://gre/modules/FirefoxRelay.sys.mjs",
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+  MigrationUtils: "resource:///modules/MigrationUtils.sys.mjs",
+  NimbusFeatures: "resource://nimbus/ExperimentAPI.sys.mjs",
+  WebAuthnFeature: "resource://gre/modules/WebAuthnFeature.sys.mjs",
+  PasswordGenerator: "resource://gre/modules/PasswordGenerator.sys.mjs",
+  PrivateBrowsingUtils: "resource://gre/modules/PrivateBrowsingUtils.sys.mjs",
+});
+
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "prompterSvc",
+  "@mozilla.org/login-manager/prompter;1",
+  Ci.nsILoginManagerPrompter
+);
+
+ChromeUtils.defineLazyGetter(lazy, "log", () => {
+  let logger = lazy.LoginHelper.createLogger("LoginManagerParent");
+  return logger.log.bind(logger);
+});
+ChromeUtils.defineLazyGetter(lazy, "debug", () => {
+  let logger = lazy.LoginHelper.createLogger("LoginManagerParent");
+  return logger.debug.bind(logger);
+});
+
+/**
+ * A listener for notifications to tests.
+ */
+let gListenerForTests = null;
+
+/**
+ * A map of a principal's origin (including suffixes) to a generated password string and filled flag
+ * so that we can offer the same password later (e.g. in a confirmation field).
+ *
+ * We don't currently evict from this cache so entries should last until the end of the browser
+ * session. That may change later but for now a typical session would max out at a few entries.
+ */
+let gGeneratedPasswordsByPrincipalOrigin = new Map();
+
+/**
+ * Reference to the default LoginRecipesParent (instead of the initialization promise) for
+ * synchronous access. This is a temporary hack and new consumers should yield on
+ * recipeParentPromise instead.
+ *
+ * @type LoginRecipesParent
+ * @deprecated
+ */
+let gRecipeManager = null;
+
+/**
+ * Tracks the last time the user cancelled the primary password prompt,
+ *  to avoid spamming primary password prompts on autocomplete searches.
+ */
+let gLastMPLoginCancelled = Number.NEGATIVE_INFINITY;
+
+let gGeneratedPasswordObserver = {
+  addedObserver: false,
+
+  observe(subject, topic, data) {
+    if (topic == "last-pb-context-exited") {
+      // The last private browsing context closed so clear all cached generated
+      // passwords for private window origins.
+      for (let principalOrigin of gGeneratedPasswordsByPrincipalOrigin.keys()) {
+        let principal =
+          Services.scriptSecurityManager.createContentPrincipalFromOrigin(
+            principalOrigin
+          );
+        if (!principal.privateBrowsingId) {
+          // The origin isn't for a private context so leave it alone.
+          continue;
+        }
+        gGeneratedPasswordsByPrincipalOrigin.delete(principalOrigin);
+      }
+      return;
+    }
+
+    // We cache generated passwords in gGeneratedPasswordsByPrincipalOrigin.
+    // When generated password used on the page,
+    // we store a login with generated password and without username.
+    // When user updates that autosaved login with username,
+    // we must clear cached generated password.
+    // This will generate a new password next time user needs it.
+    if (topic == "passwordmgr-storage-changed" && data == "modifyLogin") {
+      const originalLogin = subject.GetElementAt(0);
+      const updatedLogin = subject.GetElementAt(1);
+
+      if (originalLogin && !originalLogin.username && updatedLogin?.username) {
+        const generatedPassword = gGeneratedPasswordsByPrincipalOrigin.get(
+          originalLogin.origin
+        );
+
+        if (
+          originalLogin.password == generatedPassword.value &&
+          updatedLogin.password == generatedPassword.value
+        ) {
+          gGeneratedPasswordsByPrincipalOrigin.delete(originalLogin.origin);
+        }
+      }
+    }
+
+    if (
+      topic == "passwordmgr-autosaved-login-merged" ||
+      (topic == "passwordmgr-storage-changed" && data == "removeLogin")
+    ) {
+      let { origin, guid } = subject;
+      let generatedPW = gGeneratedPasswordsByPrincipalOrigin.get(origin);
+
+      // in the case where an autosaved login removed or merged into an existing login,
+      // clear the guid associated with the generated-password cache entry
+      if (
+        generatedPW &&
+        (guid == generatedPW.storageGUID ||
+          topic == "passwordmgr-autosaved-login-merged")
+      ) {
+        lazy.log(
+          `Removing storageGUID for generated-password cache entry on origin: ${origin}.`
+        );
+        generatedPW.storageGUID = null;
+      }
+    }
+  },
+};
+
+Services.ppmm.addMessageListener("PasswordManager:findRecipes", message => {
+  let formHost = new URL(message.data.formOrigin).host;
+  return gRecipeManager?.getRecipesForHost(formHost) ?? [];
+});
+
+/**
+ * Lazily create a Map of origins to array of browsers with importable logins.
+ *
+ * @param {origin} formOrigin
+ * @returns {Object?} containing array of migration browsers and experiment state.
+ */
+async function getImportableLogins(formOrigin) {
+  // Include the experiment state for data and UI decisions; otherwise skip
+  // importing if not supported or disabled.
+  const state =
+    lazy.LoginHelper.suggestImportCount > 0 &&
+    lazy.LoginHelper.showAutoCompleteImport;
+  return state
+    ? {
+        browsers: await lazy.ChromeMigrationUtils.getImportableLogins(
+          formOrigin
+        ),
+        state,
+      }
+    : null;
+}
+
+export class LoginManagerParent extends JSWindowActorParent {
+  possibleValues = {
+    // This is stored at the parent (i.e., frame) scope because the LoginManagerPrompter
+    // is shared across all frames.
+    //
+    // It is mutated to update values without forcing us to set a new doorhanger.
+    usernames: new Set(),
+    passwords: new Set(),
+  };
+
+  // This is used by tests to listen to form submission.
+  static setListenerForTests(listener) {
+    gListenerForTests = listener;
+  }
+
+  // Used by tests to clean up recipes only when they were actually used.
+  static get _recipeManager() {
+    return gRecipeManager;
+  }
+
+  // Some unit tests need to access this.
+  static getGeneratedPasswordsByPrincipalOrigin() {
+    return gGeneratedPasswordsByPrincipalOrigin;
+  }
+
+  getRootBrowser() {
+    let browsingContext = null;
+    if (this._overrideBrowsingContextId) {
+      browsingContext = BrowsingContext.get(this._overrideBrowsingContextId);
+    } else {
+      browsingContext = this.browsingContext.top;
+    }
+    return browsingContext.embedderElement;
+  }
+
+  /**
+   * @param {origin} formOrigin
+   * @param {object} options
+   * @param {origin?} options.formActionOrigin To match on. Omit this argument to match all action origins.
+   * @param {origin?} options.httpRealm To match on. Omit this argument to match all realms.
+   * @param {boolean} options.acceptDifferentSubdomains Include results for eTLD+1 matches
+   * @param {boolean} options.ignoreActionAndRealm Include all form and HTTP auth logins for the site
+   * @param {string[]} options.relatedRealms Related realms to match against when searching
+   */
+  static async searchAndDedupeLogins(
+    formOrigin,
+    {
+      acceptDifferentSubdomains,
+      formActionOrigin,
+      httpRealm,
+      ignoreActionAndRealm,
+      relatedRealms,
+    } = {}
+  ) {
+    let logins;
+    let matchData = {
+      origin: formOrigin,
+      schemeUpgrades: lazy.LoginHelper.schemeUpgrades,
+      acceptDifferentSubdomains,
+    };
+    if (!ignoreActionAndRealm) {
+      if (typeof formActionOrigin != "undefined") {
+        matchData.formActionOrigin = formActionOrigin;
+      } else if (typeof httpRealm != "undefined") {
+        matchData.httpRealm = httpRealm;
+      }
+    }
+    if (lazy.LoginHelper.relatedRealmsEnabled) {
+      matchData.acceptRelatedRealms = lazy.LoginHelper.relatedRealmsEnabled;
+      matchData.relatedRealms = relatedRealms;
+    }
+    try {
+      logins = await Services.logins.searchLoginsAsync(matchData);
+    } catch (e) {
+      // Record the last time the user cancelled the MP prompt
+      // to avoid spamming them with MP prompts for autocomplete.
+      if (e.result == Cr.NS_ERROR_ABORT) {
+        lazy.log("User cancelled primary password prompt.");
+        gLastMPLoginCancelled = Date.now();
+        return [];
+      }
+      throw e;
+    }
+
+    logins = lazy.LoginHelper.shadowHTTPLogins(logins);
+
+    let resolveBy = [
+      "subdomain",
+      "actionOrigin",
+      "scheme",
+      "timePasswordChanged",
+    ];
+    return lazy.LoginHelper.dedupeLogins(
+      logins,
+      ["username", "password"],
+      resolveBy,
+      formOrigin,
+      formActionOrigin
+    );
+  }
+
+  async receiveMessage(msg) {
+    let data = msg.data;
+    if (data.origin || data.formOrigin) {
+      throw new Error(
+        "The child process should not send an origin to the parent process. See bug 1513003"
+      );
+    }
+    let context = {};
+    ChromeUtils.defineLazyGetter(context, "origin", () => {
+      // We still need getLoginOrigin to remove the path for file: URIs until we fix bug 1625391.
+      let origin = lazy.LoginHelper.getLoginOrigin(
+        this.manager.documentPrincipal?.originNoSuffix
+      );
+      if (!origin) {
+        throw new Error("An origin is required. Message name: " + msg.name);
+      }
+      return origin;
+    });
+
+    switch (msg.name) {
+      case "PasswordManager:updateDoorhangerSuggestions": {
+        this.#onUpdateDoorhangerSuggestions(data.possibleValues);
+        break;
+      }
+
+      case "PasswordManager:decreaseSuggestImportCount": {
+        this.decreaseSuggestImportCount(data);
+        break;
+      }
+
+      case "PasswordManager:findLogins": {
+        return this.sendLoginDataToChild(
+          context.origin,
+          data.actionOrigin,
+          data.options
+        );
+      }
+
+      case "PasswordManager:onFormSubmit": {
+        this.#onFormSubmit(context);
+        break;
+      }
+
+      case "PasswordManager:onPasswordEditedOrGenerated": {
+        this.#onPasswordEditedOrGenerated(context, data);
+        break;
+      }
+
+      case "PasswordManager:onIgnorePasswordEdit": {
+        this.#onIgnorePasswordEdit();
+        break;
+      }
+
+      case "PasswordManager:ShowDoorhanger": {
+        this.#onShowDoorhanger(context, data);
+        break;
+      }
+
+      case "PasswordManager:autoCompleteLogins": {
+        return this.doAutocompleteSearch(context.origin, data);
+      }
+
+      case "PasswordManager:removeLogin": {
+        this.#onRemoveLogin(data.login);
+        break;
+      }
+
+      case "PasswordManager:OpenImportableLearnMore": {
+        this.#onOpenImportableLearnMore();
+        break;
+      }
+
+      case "PasswordManager:HandleImportable": {
+        await this.#onHandleImportable(data.browserId);
+        break;
+      }
+
+      case "PasswordManager:OpenPreferences": {
+        this.#onOpenPreferences(data.hostname, data.entryPoint);
+        break;
+      }
+
+      // Used by tests to detect that a form-fill has occurred. This redirects
+      // to the top-level browsing context.
+      case "PasswordManager:formProcessed": {
+        this.#onFormProcessed(data.formid, data.autofillResult);
+        break;
+      }
+
+      case "PasswordManager:offerRelayIntegration": {
+        FirefoxRelayTelemetry.recordRelayOfferedEvent(
+          "clicked",
+          data.telemetry.flowId,
+          data.telemetry.scenarioName
+        );
+        return this.#offerRelayIntegration(context.origin);
+      }
+
+      case "PasswordManager:generateRelayUsername": {
+        FirefoxRelayTelemetry.recordRelayUsernameFilledEvent(
+          "clicked",
+          data.telemetry.flowId
+        );
+        return this.#generateRelayUsername(context.origin);
+      }
+
+      case "PasswordManager:promptForAuthenticator": {
+        return this.#promptForAuthenticator(data.selection);
+      }
+    }
+
+    return undefined;
+  }
+
+  #onUpdateDoorhangerSuggestions(possibleValues) {
+    this.possibleValues.usernames = possibleValues.usernames;
+    this.possibleValues.passwords = possibleValues.passwords;
+  }
+
+  #onFormSubmit(context) {
+    Services.obs.notifyObservers(
+      null,
+      "passwordmgr-form-submission-detected",
+      context.origin
+    );
+  }
+
+  #onPasswordEditedOrGenerated(context, data) {
+    lazy.log("#onPasswordEditedOrGenerated: Received PasswordManager.");
+    if (gListenerForTests) {
+      lazy.log("#onPasswordEditedOrGenerated: Calling gListenerForTests.");
+      gListenerForTests("PasswordEditedOrGenerated", {});
+    }
+    let browser = this.getRootBrowser();
+    this._onPasswordEditedOrGenerated(browser, context.origin, data);
+  }
+
+  #onIgnorePasswordEdit() {
+    lazy.log("#onIgnorePasswordEdit: Received PasswordManager.");
+    if (gListenerForTests) {
+      lazy.log("#onIgnorePasswordEdit: Calling gListenerForTests.");
+      gListenerForTests("PasswordIgnoreEdit", {});
+    }
+  }
+
+  #onShowDoorhanger(context, data) {
+    const browser = this.getRootBrowser();
+    const submitPromise = this.showDoorhanger(browser, context.origin, data);
+    if (gListenerForTests) {
+      submitPromise.then(() => {
+        gListenerForTests("ShowDoorhanger", {
+          origin: context.origin,
+          data,
+        });
+      });
+    }
+  }
+
+  #onRemoveLogin(login) {
+    login = lazy.LoginHelper.vanillaObjectToLogin(login);
+    Services.logins.removeLogin(login);
+  }
+
+  #onOpenImportableLearnMore() {
+    const window = this.getRootBrowser().ownerGlobal;
+    window.openTrustedLinkIn(
+      Services.urlFormatter.formatURLPref("app.support.baseURL") +
+        "password-import",
+      "tab",
+      { relatedToCurrent: true }
+    );
+  }
+
+  async #onHandleImportable(browserId) {
+    // Directly migrate passwords for a single profile.
+    const migrator = await lazy.MigrationUtils.getMigrator(browserId);
+    const profiles = await migrator.getSourceProfiles();
+    if (
+      profiles.length == 1 &&
+      lazy.NimbusFeatures["password-autocomplete"].getVariable(
+        "directMigrateSingleProfile"
+      )
+    ) {
+      const loginAdded = new Promise(resolve => {
+        const obs = (_subject, _topic, data) => {
+          if (data == "addLogin") {
+            Services.obs.removeObserver(obs, "passwordmgr-storage-changed");
+            resolve();
+          }
+        };
+        Services.obs.addObserver(obs, "passwordmgr-storage-changed");
+      });
+
+      await migrator.migrate(
+        lazy.MigrationUtils.resourceTypes.PASSWORDS,
+        null,
+        profiles[0]
+      );
+      await loginAdded;
+
+      // Reshow the popup with the imported password.
+      this.sendAsyncMessage("PasswordManager:repopulateAutocompletePopup");
+    } else {
+      // Open the migration wizard pre-selecting the appropriate browser.
+      lazy.MigrationUtils.showMigrationWizard(
+        this.getRootBrowser().ownerGlobal,
+        {
+          entrypoint: lazy.MigrationUtils.MIGRATION_ENTRYPOINTS.PASSWORDS,
+          migratorKey: browserId,
+        }
+      );
+    }
+  }
+
+  #onOpenPreferences(hostname, entryPoint) {
+    const window = this.getRootBrowser().ownerGlobal;
+    lazy.LoginHelper.openPasswordManager(window, {
+      filterString: hostname,
+      entryPoint,
+    });
+  }
+
+  #onFormProcessed(formid, autofillResult) {
+    const topActor =
+      this.browsingContext.currentWindowGlobal.getActor("LoginManager");
+    topActor.sendAsyncMessage("PasswordManager:formProcessed", { formid });
+    if (gListenerForTests) {
+      gListenerForTests("FormProcessed", {
+        browsingContext: this.browsingContext,
+        data: {
+          formId: formid,
+          autofillResult,
+        },
+      });
+    }
+  }
+
+  async #offerRelayIntegration(origin) {
+    const browser = lazy.LoginHelper.getBrowserForPrompt(this.getRootBrowser());
+    return lazy.FirefoxRelay.offerRelayIntegration(browser, origin);
+  }
+
+  async #generateRelayUsername(origin) {
+    const browser = lazy.LoginHelper.getBrowserForPrompt(this.getRootBrowser());
+    return lazy.FirefoxRelay.generateUsername(browser, origin);
+  }
+
+  async #promptForAuthenticator(selection) {
+    const browser = lazy.LoginHelper.getBrowserForPrompt(this.getRootBrowser());
+    return lazy.WebAuthnFeature.promptForAuthenticator(browser, selection);
+  }
+
+  /**
+   * Update the remaining number of import suggestion impressions with debounce
+   * to allow multiple popups showing the "same" items to count as one.
+   */
+  decreaseSuggestImportCount(count) {
+    // Delay an existing timer with a potentially larger count.
+    if (this._suggestImportTimer) {
+      this._suggestImportTimer.delay =
+        LoginManagerParent.SUGGEST_IMPORT_DEBOUNCE_MS;
+      this._suggestImportCount = Math.max(count, this._suggestImportCount);
+      return;
+    }
+
+    this._suggestImportTimer = Cc["@mozilla.org/timer;1"].createInstance(
+      Ci.nsITimer
+    );
+    this._suggestImportTimer.init(
+      () => {
+        this._suggestImportTimer = null;
+        Services.prefs.setIntPref(
+          "signon.suggestImportCount",
+          lazy.LoginHelper.suggestImportCount - this._suggestImportCount
+        );
+      },
+      LoginManagerParent.SUGGEST_IMPORT_DEBOUNCE_MS,
+      Ci.nsITimer.TYPE_ONE_SHOT
+    );
+    this._suggestImportCount = count;
+  }
+
+  async #getRecipesForHost(origin) {
+    let recipes;
+    if (origin) {
+      try {
+        const formHost = new URL(origin).host;
+        let recipeManager = await LoginManagerParent.recipeParentPromise;
+        recipes = recipeManager.getRecipesForHost(formHost);
+      } catch (ex) {
+        // Some schemes e.g. chrome aren't supported by URL
+      }
+    }
+
+    return recipes ?? [];
+  }
+
+  /**
+   * Trigger a login form fill and send relevant data (e.g. logins and recipes)
+   * to the child process (LoginManagerChild).
+   */
+  async fillForm({
+    browser,
+    loginFormOrigin,
+    login,
+    inputElementIdentifier,
+    style,
+  }) {
+    const recipes = await this.#getRecipesForHost(loginFormOrigin);
+
+    // Convert the array of nsILoginInfo to vanilla JS objects since nsILoginInfo
+    // doesn't support structured cloning.
+    const jsLogins = [lazy.LoginHelper.loginToVanillaObject(login)];
+
+    const browserURI = browser.currentURI.spec;
+    const originMatches =
+      lazy.LoginHelper.getLoginOrigin(browserURI) == loginFormOrigin;
+
+    this.sendAsyncMessage("PasswordManager:fillForm", {
+      inputElementIdentifier,
+      loginFormOrigin,
+      originMatches,
+      logins: jsLogins,
+      recipes,
+      style,
+    });
+  }
+
+  /**
+   * Send relevant data (e.g. logins and recipes) to the child process (LoginManagerChild).
+   */
+  async sendLoginDataToChild(
+    formOrigin,
+    actionOrigin,
+    { guid, showPrimaryPassword }
+  ) {
+    const recipes = await this.#getRecipesForHost(formOrigin);
+
+    if (!showPrimaryPassword && !Services.logins.isLoggedIn) {
+      return { logins: [], recipes };
+    }
+
+    // If we're currently displaying a primary password prompt, defer
+    // processing this form until the user handles the prompt.
+    if (Services.logins.uiBusy) {
+      lazy.log(
+        "UI is busy. Deferring sendLoginDataToChild for form: ",
+        formOrigin
+      );
+
+      let uiBusyPromiseResolve;
+      const uiBusyPromise = new Promise(resolve => {
+        uiBusyPromiseResolve = resolve;
+      });
+
+      const self = this;
+      const observer = {
+        QueryInterface: ChromeUtils.generateQI([
+          "nsIObserver",
+          "nsISupportsWeakReference",
+        ]),
+
+        observe(_subject, topic, _data) {
+          lazy.log("Got deferred sendLoginDataToChild notification:", topic);
+          // Only run observer once.
+          Services.obs.removeObserver(this, "passwordmgr-crypto-login");
+          Services.obs.removeObserver(this, "passwordmgr-crypto-loginCanceled");
+          if (topic == "passwordmgr-crypto-loginCanceled") {
+            uiBusyPromiseResolve({ logins: [], recipes });
+            return;
+          }
+
+          const result = self.sendLoginDataToChild(formOrigin, actionOrigin, {
+            showPrimaryPassword,
+          });
+          uiBusyPromiseResolve(result);
+        },
+      };
+
+      // Possible leak: it's possible that neither of these notifications
+      // will fire, and if that happens, we'll leak the observer (and
+      // never return). We should guarantee that at least one of these
+      // will fire.
+      // See bug XXX.
+      Services.obs.addObserver(observer, "passwordmgr-crypto-login");
+      Services.obs.addObserver(observer, "passwordmgr-crypto-loginCanceled");
+
+      return uiBusyPromise;
+    }
+
+    // Autocomplete results do not need to match actionOrigin or exact origin.
+    let logins = null;
+    if (guid) {
+      logins = await Services.logins.searchLoginsAsync({
+        guid,
+        origin: formOrigin,
+      });
+    } else {
+      let relatedRealmsOrigins = [];
+      if (lazy.LoginHelper.relatedRealmsEnabled) {
+        relatedRealmsOrigins =
+          await lazy.LoginRelatedRealmsParent.findRelatedRealms(formOrigin);
+      }
+      logins = await LoginManagerParent.searchAndDedupeLogins(formOrigin, {
+        formActionOrigin: actionOrigin,
+        ignoreActionAndRealm: true,
+        acceptDifferentSubdomains:
+          lazy.LoginHelper.includeOtherSubdomainsInLookup,
+        relatedRealms: relatedRealmsOrigins,
+      });
+
+      if (lazy.LoginHelper.relatedRealmsEnabled) {
+        lazy.debug(
+          "Adding related logins on page load",
+          logins.map(l => l.origin)
+        );
+      }
+    }
+    lazy.log(`Deduped ${logins.length} logins.`);
+    // Convert the array of nsILoginInfo to vanilla JS objects since nsILoginInfo
+    // doesn't support structured cloning.
+    let jsLogins = lazy.LoginHelper.loginsToVanillaObjects(logins);
+    return {
+      importable: await getImportableLogins(formOrigin),
+      logins: jsLogins,
+      recipes,
+    };
+  }
+
+  async doAutocompleteSearch(
+    formOrigin,
+    {
+      actionOrigin,
+      searchString,
+      previousResult,
+      forcePasswordGeneration,
+      hasBeenTypePassword,
+      isProbablyANewPasswordField,
+      scenarioName,
+      inputMaxLength,
+      isWebAuthn,
+    }
+  ) {
+    // Note: previousResult is a regular object, not an
+    // nsIAutoCompleteResult.
+
+    // Cancel if the primary password prompt is already showing or we unsuccessfully prompted for it too recently.
+    if (!Services.logins.isLoggedIn) {
+      if (Services.logins.uiBusy) {
+        lazy.log(
+          "Not searching logins for autocomplete since the primary password prompt is already showing."
+        );
+        // Return an empty array to make LoginManagerChild clear the
+        // outstanding request it has temporarily saved.
+        return { logins: [] };
+      }
+
+      const timeDiff = Date.now() - gLastMPLoginCancelled;
+      if (timeDiff < LoginManagerParent._repromptTimeout) {
+        lazy.log(
+          `Not searching logins for autocomplete since the primary password prompt was last cancelled ${Math.round(
+            timeDiff / 1000
+          )} seconds ago.`
+        );
+        // Return an empty array to make LoginManagerChild clear the
+        // outstanding request it has temporarily saved.
+        return { logins: [] };
+      }
+    }
+
+    const searchStringLower = searchString.toLowerCase();
+    let logins;
+    if (
+      previousResult &&
+      searchStringLower.startsWith(previousResult.searchString.toLowerCase())
+    ) {
+      lazy.log("Using previous autocomplete result.");
+
+      // We have a list of results for a shorter search string, so just
+      // filter them further based on the new search string.
+      logins = lazy.LoginHelper.vanillaObjectsToLogins(previousResult.logins);
+    } else {
+      lazy.log("Creating new autocomplete search result.");
+      let relatedRealmsOrigins = [];
+      if (lazy.LoginHelper.relatedRealmsEnabled) {
+        relatedRealmsOrigins =
+          await lazy.LoginRelatedRealmsParent.findRelatedRealms(formOrigin);
+      }
+      // Autocomplete results do not need to match actionOrigin or exact origin.
+      logins = await LoginManagerParent.searchAndDedupeLogins(formOrigin, {
+        formActionOrigin: actionOrigin,
+        ignoreActionAndRealm: true,
+        acceptDifferentSubdomains:
+          lazy.LoginHelper.includeOtherSubdomainsInLookup,
+        relatedRealms: relatedRealmsOrigins,
+      });
+    }
+
+    const matchingLogins = logins.filter(fullMatch => {
+      // Remove results that are too short, or have different prefix.
+      // Also don't offer empty usernames as possible results except
+      // for on password fields.
+      if (hasBeenTypePassword) {
+        return true;
+      }
+
+      const match = fullMatch.username;
+
+      return match && match.toLowerCase().startsWith(searchStringLower);
+    });
+
+    let generatedPassword = null;
+    let willAutoSaveGeneratedPassword = false;
+    if (
+      // If MP was cancelled above, don't try to offer pwgen or access storage again (causing a new MP prompt).
+      Services.logins.isLoggedIn &&
+      (forcePasswordGeneration ||
+        (isProbablyANewPasswordField &&
+          Services.logins.getLoginSavingEnabled(formOrigin)))
+    ) {
+      // We either generate a new password here, or grab the previously generated password
+      // if we're still on the same domain when we generated the password
+      generatedPassword = await this.getGeneratedPassword({ inputMaxLength });
+      const potentialConflictingLogins =
+        await Services.logins.searchLoginsAsync({
+          origin: formOrigin,
+          formActionOrigin: actionOrigin,
+          httpRealm: null,
+        });
+      willAutoSaveGeneratedPassword = !potentialConflictingLogins.find(
+        login => login.username == ""
+      );
+    }
+
+    // Convert the array of nsILoginInfo to vanilla JS objects since nsILoginInfo
+    // doesn't support structured cloning.
+    let jsLogins = lazy.LoginHelper.loginsToVanillaObjects(matchingLogins);
+
+    let autocompleteItems = [];
+
+    if (!hasBeenTypePassword) {
+      autocompleteItems.push(
+        ...(await lazy.FirefoxRelay.autocompleteItemsAsync({
+          formOrigin,
+          scenarioName,
+          hasInput: !!searchStringLower.length,
+        }))
+      );
+    }
+    autocompleteItems.push(
+      ...(await lazy.WebAuthnFeature.autocompleteItemsAsync(
+        this._overrideBrowsingContextId ??
+          this.getRootBrowser().browsingContext.id,
+        formOrigin,
+        scenarioName,
+        isWebAuthn
+      ))
+    );
+
+    return {
+      generatedPassword,
+      importable: await getImportableLogins(formOrigin),
+      autocompleteItems,
+      logins: jsLogins,
+      willAutoSaveGeneratedPassword,
+    };
+  }
+
+  /**
+   * Expose `BrowsingContext` so we can stub it in tests.
+   */
+  static get _browsingContextGlobal() {
+    return BrowsingContext;
+  }
+
+  // Set an override context within a test.
+  useBrowsingContext(browsingContextId = 0) {
+    this._overrideBrowsingContextId = browsingContextId;
+  }
+
+  getBrowsingContextToUse() {
+    if (this._overrideBrowsingContextId) {
+      return BrowsingContext.get(this._overrideBrowsingContextId);
+    }
+
+    return this.browsingContext;
+  }
+
+  async getGeneratedPassword({ inputMaxLength } = {}) {
+    if (
+      !lazy.LoginHelper.enabled ||
+      !lazy.LoginHelper.generationAvailable ||
+      !lazy.LoginHelper.generationEnabled
+    ) {
+      return null;
+    }
+
+    let browsingContext = this.getBrowsingContextToUse();
+    if (!browsingContext) {
+      return null;
+    }
+    let framePrincipalOrigin =
+      browsingContext.currentWindowGlobal.documentPrincipal.origin;
+    // Use the same password if we already generated one for this origin so that it doesn't change
+    // with each search/keystroke and the user can easily re-enter a password in a confirmation field.
+    let generatedPW =
+      gGeneratedPasswordsByPrincipalOrigin.get(framePrincipalOrigin);
+    if (generatedPW) {
+      return generatedPW.value;
+    }
+
+    generatedPW = {
+      autocompleteShown: false,
+      edited: false,
+      filled: false,
+      /**
+       * GUID of a login that was already saved for this generated password that
+       * will be automatically updated with password changes. This shouldn't be
+       * an existing saved login for the site unless the user chose to
+       * merge/overwrite via a doorhanger.
+       */
+      storageGUID: null,
+    };
+    if (lazy.LoginHelper.improvedPasswordRulesEnabled) {
+      generatedPW.value = await lazy.PasswordRulesManager.generatePassword(
+        browsingContext.currentWindowGlobal.documentURI,
+        { inputMaxLength }
+      );
+    } else {
+      generatedPW.value = lazy.PasswordGenerator.generatePassword({
+        inputMaxLength,
+      });
+    }
+
+    // Add these observers when a password is assigned.
+    if (!gGeneratedPasswordObserver.addedObserver) {
+      Services.obs.addObserver(
+        gGeneratedPasswordObserver,
+        "passwordmgr-autosaved-login-merged"
+      );
+      Services.obs.addObserver(
+        gGeneratedPasswordObserver,
+        "passwordmgr-storage-changed"
+      );
+      Services.obs.addObserver(
+        gGeneratedPasswordObserver,
+        "last-pb-context-exited"
+      );
+      gGeneratedPasswordObserver.addedObserver = true;
+    }
+
+    gGeneratedPasswordsByPrincipalOrigin.set(framePrincipalOrigin, generatedPW);
+    return generatedPW.value;
+  }
+
+  maybeRecordPasswordGenerationShownTelemetryEvent(autocompleteResults) {
+    if (!autocompleteResults.some(r => r.style == "generatedPassword")) {
+      return;
+    }
+
+    let browsingContext = this.getBrowsingContextToUse();
+
+    let framePrincipalOrigin =
+      browsingContext.currentWindowGlobal.documentPrincipal.origin;
+    let generatedPW =
+      gGeneratedPasswordsByPrincipalOrigin.get(framePrincipalOrigin);
+
+    // We only want to record the first time it was shown for an origin
+    if (generatedPW.autocompleteShown) {
+      return;
+    }
+
+    generatedPW.autocompleteShown = true;
+
+    Services.telemetry.recordEvent(
+      "pwmgr",
+      "autocomplete_shown",
+      "generatedpassword"
+    );
+  }
+
+  /**
+   * Used for stubbing by tests.
+   */
+  _getPrompter() {
+    return lazy.prompterSvc;
+  }
+
+  // Look for an existing login that matches the form login.
+  #findSameLogin(logins, formLogin) {
+    return logins.find(login => {
+      let same;
+
+      // If one login has a username but the other doesn't, ignore
+      // the username when comparing and only match if they have the
+      // same password. Otherwise, compare the logins and match even
+      // if the passwords differ.
+      if (!login.username && formLogin.username) {
+        let restoreMe = formLogin.username;
+        formLogin.username = "";
+        same = lazy.LoginHelper.doLoginsMatch(formLogin, login, {
+          ignorePassword: false,
+          ignoreSchemes: lazy.LoginHelper.schemeUpgrades,
+        });
+        formLogin.username = restoreMe;
+      } else if (!formLogin.username && login.username) {
+        formLogin.username = login.username;
+        same = lazy.LoginHelper.doLoginsMatch(formLogin, login, {
+          ignorePassword: false,
+          ignoreSchemes: lazy.LoginHelper.schemeUpgrades,
+        });
+        formLogin.username = ""; // we know it's always blank.
+      } else {
+        same = lazy.LoginHelper.doLoginsMatch(formLogin, login, {
+          ignorePassword: true,
+          ignoreSchemes: lazy.LoginHelper.schemeUpgrades,
+        });
+      }
+
+      return same;
+    });
+  }
+
+  async showDoorhanger(
+    browser,
+    formOrigin,
+    {
+      browsingContextId,
+      formActionOrigin,
+      autoFilledLoginGuid,
+      usernameField,
+      newPasswordField,
+      oldPasswordField,
+      dismissedPrompt,
+    }
+  ) {
+    function recordLoginUse(login) {
+      Services.logins.recordPasswordUse(
+        login,
+        browser && lazy.PrivateBrowsingUtils.isBrowserPrivate(browser),
+        login.username ? "form_login" : "form_password",
+        !!autoFilledLoginGuid
+      );
+    }
+
+    // If password storage is disabled, bail out.
+    if (!lazy.LoginHelper.storageEnabled) {
+      return;
+    }
+
+    if (!Services.logins.getLoginSavingEnabled(formOrigin)) {
+      lazy.log(
+        `Form submission ignored because saving is disabled for origin: ${formOrigin}.`
+      );
+      return;
+    }
+
+    let browsingContext = BrowsingContext.get(browsingContextId);
+    let framePrincipalOrigin =
+      browsingContext.currentWindowGlobal.documentPrincipal.origin;
+
+    let formLogin = new LoginInfo(
+      formOrigin,
+      formActionOrigin,
+      null,
+      usernameField?.value ?? "",
+      newPasswordField.value,
+      usernameField?.name ?? "",
+      newPasswordField.name
+    );
+    // we don't auto-save logins on form submit
+    let notifySaved = false;
+
+    if (autoFilledLoginGuid) {
+      let loginsForGuid = await Services.logins.searchLoginsAsync({
+        guid: autoFilledLoginGuid,
+        origin: formOrigin, // Ignored outside of GV.
+      });
+      if (
+        loginsForGuid.length == 1 &&
+        loginsForGuid[0].password == formLogin.password &&
+        (!formLogin.username || // Also cover cases where only the password is requested.
+          loginsForGuid[0].username == formLogin.username)
+      ) {
+        lazy.log(
+          "The filled login matches the form submission. Nothing to change."
+        );
+        recordLoginUse(loginsForGuid[0]);
+        return;
+      }
+    }
+
+    let existingLogin = null;
+    let canMatchExistingLogin = true;
+    // Below here we have one login per hostPort + action + username with the
+    // matching scheme being preferred.
+    const logins = await LoginManagerParent.searchAndDedupeLogins(formOrigin, {
+      formActionOrigin,
+    });
+
+    const generatedPW =
+      gGeneratedPasswordsByPrincipalOrigin.get(framePrincipalOrigin);
+    const autoSavedStorageGUID = generatedPW?.storageGUID ?? "";
+
+    // If we didn't find a username field, but seem to be changing a
+    // password, allow the user to select from a list of applicable
+    // logins to update the password for.
+    if (!usernameField && oldPasswordField && logins.length) {
+      if (logins.length == 1) {
+        existingLogin = logins[0];
+
+        if (existingLogin.password == formLogin.password) {
+          recordLoginUse(existingLogin);
+          lazy.log(
+            "Not prompting to save/change since we have no username and the only saved password matches the new password."
+          );
+          return;
+        }
+
+        formLogin.username = existingLogin.username;
+        formLogin.usernameField = existingLogin.usernameField;
+      } else if (!generatedPW || generatedPW.value != newPasswordField.value) {
+        // Note: It's possible that that we already have the correct u+p saved
+        // but since we don't have the username, we don't know if the user is
+        // changing a second account to the new password so we ask anyways.
+        canMatchExistingLogin = false;
+      }
+    }
+
+    if (canMatchExistingLogin && !existingLogin) {
+      existingLogin = this.#findSameLogin(logins, formLogin);
+    }
+
+    const promptBrowser = lazy.LoginHelper.getBrowserForPrompt(browser);
+    const prompter = this._getPrompter(browser);
+
+    if (!canMatchExistingLogin) {
+      prompter.promptToChangePasswordWithUsernames(
+        promptBrowser,
+        logins,
+        formLogin
+      );
+      return;
+    }
+
+    if (existingLogin) {
+      lazy.log("Found an existing login matching this form submission.");
+
+      // Change password if needed.
+      if (existingLogin.password != formLogin.password) {
+        lazy.log("Passwords differ, prompting to change.");
+        prompter.promptToChangePassword(
+          promptBrowser,
+          existingLogin,
+          formLogin,
+          dismissedPrompt,
+          notifySaved,
+          autoSavedStorageGUID,
+          autoFilledLoginGuid,
+          this.possibleValues
+        );
+      } else if (!existingLogin.username && formLogin.username) {
+        lazy.log("Empty username update, prompting to change.");
+        prompter.promptToChangePassword(
+          promptBrowser,
+          existingLogin,
+          formLogin,
+          dismissedPrompt,
+          notifySaved,
+          autoSavedStorageGUID,
+          autoFilledLoginGuid,
+          this.possibleValues
+        );
+      } else {
+        recordLoginUse(existingLogin);
+      }
+
+      return;
+    }
+
+    // Prompt user to save login (via dialog or notification bar)
+    prompter.promptToSavePassword(
+      promptBrowser,
+      formLogin,
+      dismissedPrompt,
+      notifySaved,
+      autoFilledLoginGuid,
+      this.possibleValues
+    );
+  }
+
+  /**
+   * Performs validation of inputs against already-saved logins in order to determine whether and
+   * how these inputs can be stored. Depending on validation, will either no-op or show a 'save'
+   * or 'update' dialog to the user.
+   *
+   * This is called after any of the following:
+   *   - The user edits a password
+   *   - A generated password is filled
+   *   - The user edits a username (when a matching password field has already been filled)
+   *
+   * @param {Element} browser
+   * @param {string} formOrigin
+   * @param {string} options.formActionOrigin
+   * @param {string?} options.autoFilledLoginGuid
+   * @param {Object} options.newPasswordField
+   * @param {Object?} options.usernameField
+   * @param {Element?} options.oldPasswordField
+   * @param {boolean} [options.triggeredByFillingGenerated = false]
+   */
+  /* eslint-disable-next-line complexity */
+  async _onPasswordEditedOrGenerated(
+    browser,
+    formOrigin,
+    {
+      formActionOrigin,
+      autoFilledLoginGuid,
+      newPasswordField,
+      usernameField = null,
+      oldPasswordField,
+      triggeredByFillingGenerated = false,
+    }
+  ) {
+    lazy.log(
+      `_onPasswordEditedOrGenerated: triggeredByFillingGenerated: ${triggeredByFillingGenerated}.`
+    );
+
+    // If password storage is disabled, bail out.
+    if (!lazy.LoginHelper.storageEnabled) {
+      return;
+    }
+
+    if (!Services.logins.getLoginSavingEnabled(formOrigin)) {
+      // No UI should be shown to offer generation in this case but a user may
+      // disable saving for the site after already filling one and they may then
+      // edit it.
+      lazy.log(`Saving is disabled for origin: ${formOrigin}.`);
+      return;
+    }
+
+    if (!newPasswordField.value) {
+      lazy.log("The password field is empty.");
+      return;
+    }
+
+    if (!browser) {
+      lazy.log("The browser is gone.");
+      return;
+    }
+
+    let browsingContext = this.getBrowsingContextToUse();
+    if (!browsingContext) {
+      return;
+    }
+
+    if (!triggeredByFillingGenerated && !Services.logins.isLoggedIn) {
+      // Don't show the dismissed doorhanger on "input" or "change" events
+      // when the Primary Password is locked
+      lazy.log(
+        "Edited field is not a generated password field, and Primary Password is locked."
+      );
+      return;
+    }
+
+    let framePrincipalOrigin =
+      browsingContext.currentWindowGlobal.documentPrincipal.origin;
+
+    lazy.log("Got framePrincipalOrigin: ", framePrincipalOrigin);
+
+    let formLogin = new LoginInfo(
+      formOrigin,
+      formActionOrigin,
+      null,
+      usernameField?.value ?? "",
+      newPasswordField.value,
+      usernameField?.name ?? "",
+      newPasswordField.name
+    );
+    let existingLogin = null;
+    let canMatchExistingLogin = true;
+    let shouldAutoSaveLogin = triggeredByFillingGenerated;
+    let autoSavedLogin = null;
+    let notifySaved = false;
+
+    if (autoFilledLoginGuid) {
+      let [matchedLogin] = await Services.logins.searchLoginsAsync({
+        guid: autoFilledLoginGuid,
+        origin: formOrigin, // Ignored outside of GV.
+      });
+      if (
+        matchedLogin &&
+        matchedLogin.password == formLogin.password &&
+        (!formLogin.username || // Also cover cases where only the password is requested.
+          matchedLogin.username == formLogin.username)
+      ) {
+        lazy.log(
+          "The filled login matches the changed fields. Nothing to change."
+        );
+        // We may want to update an existing doorhanger
+        existingLogin = matchedLogin;
+      }
+    }
+
+    let generatedPW =
+      gGeneratedPasswordsByPrincipalOrigin.get(framePrincipalOrigin);
+
+    // Below here we have one login per hostPort + action + username with the
+    // matching scheme being preferred.
+    let logins = await LoginManagerParent.searchAndDedupeLogins(formOrigin, {
+      formActionOrigin,
+    });
+    // only used in the generated pw case where we auto-save
+    let formLoginWithoutUsername;
+
+    if (triggeredByFillingGenerated && generatedPW) {
+      lazy.log("Got cached generatedPW.");
+      formLoginWithoutUsername = new LoginInfo(
+        formOrigin,
+        formActionOrigin,
+        null,
+        "",
+        newPasswordField.value
+      );
+
+      if (newPasswordField.value != generatedPW.value) {
+        // The user edited the field after generation to a non-empty value.
+        lazy.log("The field containing the generated password has changed.");
+
+        // Record telemetry for the first edit
+        if (!generatedPW.edited) {
+          Services.telemetry.recordEvent(
+            "pwmgr",
+            "filled_field_edited",
+            "generatedpassword"
+          );
+          lazy.log("filled_field_edited telemetry event recorded.");
+          generatedPW.edited = true;
+        }
+      }
+
+      // This will throw if we can't look up the entry in the password/origin map
+      if (!generatedPW.filled) {
+        if (generatedPW.storageGUID) {
+          throw new Error(
+            "Generated password was saved in storage without being filled first"
+          );
+        }
+        // record first use of this generated password
+        Services.telemetry.recordEvent(
+          "pwmgr",
+          "autocomplete_field",
+          "generatedpassword"
+        );
+        lazy.log("autocomplete_field telemetry event recorded.");
+        generatedPW.filled = true;
+      }
+
+      // We may have already autosaved this login
+      // Note that it could have been saved in a totally different tab in the session.
+      if (generatedPW.storageGUID) {
+        [autoSavedLogin] = await Services.logins.searchLoginsAsync({
+          guid: generatedPW.storageGUID,
+          origin: formOrigin, // Ignored outside of GV.
+        });
+
+        if (autoSavedLogin) {
+          lazy.log("login to change is the auto-saved login.");
+          existingLogin = autoSavedLogin;
+        }
+        // The generated password login may have been deleted in the meantime.
+        // Proceed to maybe save a new login below.
+      }
+      generatedPW.value = newPasswordField.value;
+
+      if (!existingLogin) {
+        lazy.log("Did not match generated-password login.");
+
+        // Check if we already have a login saved for this site since we don't want to overwrite it in
+        // case the user still needs their old password to successfully complete a password change.
+        let matchedLogin = logins.find(login =>
+          formLoginWithoutUsername.matches(login, true)
+        );
+        if (matchedLogin) {
+          shouldAutoSaveLogin = false;
+          if (matchedLogin.password == formLoginWithoutUsername.password) {
+            // This login is already saved so show no new UI.
+            // We may want to update an existing doorhanger though...
+            lazy.log("Matching login already saved.");
+            existingLogin = matchedLogin;
+          }
+          lazy.log(
+            "_onPasswordEditedOrGenerated: Login with empty username already saved for this site."
+          );
+        }
+      }
+    }
+
+    // If we didn't find a username field, but seem to be changing a
+    // password, use the first match if there is only one
+    // If there's more than one we'll prompt to save with the initial formLogin
+    // and let the doorhanger code resolve this
+    if (
+      !triggeredByFillingGenerated &&
+      !existingLogin &&
+      !usernameField &&
+      oldPasswordField &&
+      logins.length
+    ) {
+      if (logins.length == 1) {
+        existingLogin = logins[0];
+
+        if (existingLogin.password == formLogin.password) {
+          lazy.log(
+            "Not prompting to save/change since we have no username and the " +
+              "only saved password matches the new password."
+          );
+          return;
+        }
+
+        formLogin.username = existingLogin.username;
+        formLogin.usernameField = existingLogin.usernameField;
+      } else if (!generatedPW || generatedPW.value != newPasswordField.value) {
+        // Note: It's possible that that we already have the correct u+p saved
+        // but since we don't have the username, we don't know if the user is
+        // changing a second account to the new password so we ask anyways.
+        canMatchExistingLogin = false;
+      }
+    }
+
+    if (canMatchExistingLogin && !existingLogin) {
+      existingLogin = this.#findSameLogin(logins, formLogin);
+      if (existingLogin) {
+        lazy.log("Matched saved login.");
+      }
+    }
+
+    if (shouldAutoSaveLogin) {
+      if (
+        existingLogin &&
+        existingLogin == autoSavedLogin &&
+        existingLogin.password !== formLogin.password
+      ) {
+        lazy.log("Updating auto-saved login.");
+
+        Services.logins.modifyLogin(
+          existingLogin,
+          lazy.LoginHelper.newPropertyBag({
+            password: formLogin.password,
+          })
+        );
+        notifySaved = true;
+        // Update `existingLogin` with the new password if modifyLogin didn't
+        // throw so that the prompts later uses the new password.
+        existingLogin.password = formLogin.password;
+      } else if (!autoSavedLogin) {
+        lazy.log("Auto-saving new login with empty username.");
+        existingLogin = await Services.logins.addLoginAsync(
+          formLoginWithoutUsername
+        );
+        // Remember the GUID where we saved the generated password so we can update
+        // the login if the user later edits the generated password.
+        generatedPW.storageGUID = existingLogin.guid;
+        notifySaved = true;
+      }
+    } else {
+      lazy.log("Not auto-saving this login.");
+    }
+
+    const prompter = this._getPrompter(browser);
+    const promptBrowser = lazy.LoginHelper.getBrowserForPrompt(browser);
+
+    if (existingLogin) {
+      // Show a change doorhanger to allow modifying an already-saved login
+      // e.g. to add a username or update the password.
+      let autoSavedStorageGUID = "";
+      if (
+        generatedPW &&
+        generatedPW.value == existingLogin.password &&
+        generatedPW.storageGUID == existingLogin.guid
+      ) {
+        autoSavedStorageGUID = generatedPW.storageGUID;
+      }
+
+      // Change password if needed.
+      if (
+        (shouldAutoSaveLogin && !formLogin.username) ||
+        existingLogin.password != formLogin.password
+      ) {
+        lazy.log(
+          `promptToChangePassword with autoSavedStorageGUID: ${autoSavedStorageGUID}`
+        );
+        prompter.promptToChangePassword(
+          promptBrowser,
+          existingLogin,
+          formLogin,
+          true, // dismissed prompt
+          notifySaved,
+          autoSavedStorageGUID, // autoSavedLoginGuid
+          autoFilledLoginGuid,
+          this.possibleValues
+        );
+      } else if (!existingLogin.username && formLogin.username) {
+        lazy.log("Empty username update, prompting to change.");
+        prompter.promptToChangePassword(
+          promptBrowser,
+          existingLogin,
+          formLogin,
+          true, // dismissed prompt
+          notifySaved,
+          autoSavedStorageGUID, // autoSavedLoginGuid
+          autoFilledLoginGuid,
+          this.possibleValues
+        );
+      } else {
+        lazy.log("No change to existing login.");
+        // is there a doorhanger we should update?
+        let popupNotifications = promptBrowser.ownerGlobal.PopupNotifications;
+        let notif = popupNotifications.getNotification("password", browser);
+        lazy.log(
+          `_onPasswordEditedOrGenerated: Has doorhanger? ${
+            notif && notif.dismissed
+          }`
+        );
+        if (notif && notif.dismissed) {
+          prompter.promptToChangePassword(
+            promptBrowser,
+            existingLogin,
+            formLogin,
+            true, // dismissed prompt
+            notifySaved,
+            autoSavedStorageGUID, // autoSavedLoginGuid
+            autoFilledLoginGuid,
+            this.possibleValues
+          );
+        }
+      }
+      return;
+    }
+    lazy.log("No matching login to save/update.");
+    prompter.promptToSavePassword(
+      promptBrowser,
+      formLogin,
+      true, // dismissed prompt
+      notifySaved,
+      autoFilledLoginGuid,
+      this.possibleValues
+    );
+  }
+
+  static get recipeParentPromise() {
+    if (!gRecipeManager) {
+      const { LoginRecipesParent } = ChromeUtils.importESModule(
+        "resource://gre/modules/LoginRecipes.sys.mjs"
+      );
+      gRecipeManager = new LoginRecipesParent({
+        defaults: Services.prefs.getStringPref("signon.recipes.path"),
+      });
+    }
+
+    return gRecipeManager.initializationPromise;
+  }
+}
+
+LoginManagerParent.SUGGEST_IMPORT_DEBOUNCE_MS = 10000;
+
+XPCOMUtils.defineLazyPreferenceGetter(
+  LoginManagerParent,
+  "_repromptTimeout",
+  "signon.masterPasswordReprompt.timeout_ms",
+  900000
+); // 15 Minutes
diff --git a/toolkit/components/passwordmgr/LoginManagerPrompter.sys.mjs b/toolkit/components/passwordmgr/LoginManagerPrompter.sys.mjs
new file mode 100644
index 0000000000..2637e8a52f
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginManagerPrompter.sys.mjs
@@ -0,0 +1,1121 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import { PrivateBrowsingUtils } from "resource://gre/modules/PrivateBrowsingUtils.sys.mjs";
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+import { showConfirmation } from "resource://gre/modules/FillHelpers.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+});
+
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "usernameAutocompleteSearch",
+  "@mozilla.org/autocomplete/search;1?name=login-doorhanger-username",
+  "nsIAutoCompleteSimpleSearch"
+);
+
+ChromeUtils.defineLazyGetter(lazy, "l10n", () => {
+  return new Localization(["toolkit/passwordmgr/passwordmgr.ftl"], true);
+});
+
+const LoginInfo = Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  "nsILoginInfo",
+  "init"
+);
+
+/**
+ * The maximum age of the password in ms (using `timePasswordChanged`) whereby
+ * a user can toggle the password visibility in a doorhanger to add a username to
+ * a saved login.
+ */
+const VISIBILITY_TOGGLE_MAX_PW_AGE_MS = 2 * 60 * 1000; // 2 minutes
+
+/**
+ * Constants for password prompt telemetry.
+ */
+const PROMPT_DISPLAYED = 0;
+const PROMPT_ADD_OR_UPDATE = 1;
+const PROMPT_NOTNOW_OR_DONTUPDATE = 2;
+const PROMPT_NEVER = 3;
+const PROMPT_DELETE = 3;
+
+/**
+ * The minimum age of a doorhanger in ms before it will get removed after a locationchange
+ */
+const NOTIFICATION_TIMEOUT_MS = 10 * 1000; // 10 seconds
+
+/**
+ * The minimum age of an attention-requiring dismissed doorhanger in ms
+ * before it will get removed after a locationchange
+ */
+const ATTENTION_NOTIFICATION_TIMEOUT_MS = 60 * 1000; // 1 minute
+
+function autocompleteSelected(popup) {
+  const doc = popup.ownerDocument;
+  const nameField = doc.getElementById("password-notification-username");
+  const passwordField = doc.getElementById("password-notification-password");
+
+  const activeElement = nameField.ownerDocument.activeElement;
+  if (activeElement == nameField) {
+    popup.onUsernameSelect();
+  } else if (activeElement == passwordField) {
+    popup.onPasswordSelect();
+  }
+}
+
+const observer = {
+  QueryInterface: ChromeUtils.generateQI(["nsIObserver"]),
+
+  // nsIObserver
+  observe(subject, topic, data) {
+    switch (topic) {
+      case "autocomplete-did-enter-text": {
+        const input = subject.QueryInterface(Ci.nsIAutoCompleteInput);
+        autocompleteSelected(input.popupElement);
+        break;
+      }
+    }
+  },
+};
+
+/**
+ * Implements interfaces for prompting the user to enter/save/change login info
+ * found in HTML forms.
+ */
+export class LoginManagerPrompter {
+  get classID() {
+    return Components.ID("{c47ff942-9678-44a5-bc9b-05e0d676c79c}");
+  }
+
+  get QueryInterface() {
+    return ChromeUtils.generateQI(["nsILoginManagerPrompter"]);
+  }
+
+  /**
+   * Called when we detect a password or username that is not yet saved as
+   * an existing login.
+   *
+   * @param {Element} aBrowser
+   *                  The browser element that the request came from.
+   * @param {nsILoginInfo} aLogin
+   *                       The new login from the page form.
+   * @param {boolean} [dismissed = false]
+   *                  If the prompt should be automatically dismissed on being shown.
+   * @param {boolean} [notifySaved = false]
+   *                  Whether the notification should indicate that a login has been saved
+   * @param {string} [autoSavedLoginGuid = ""]
+   *                 A guid value for the old login to be removed if the changes match it
+   *                 to a different login
+   * @param {object?} possibleValues
+   *                 Contains values from anything that we think, but are not sure, might be
+   *                 a username or password.  Has two properties, 'usernames' and 'passwords'.
+   * @param {Set<String>} possibleValues.usernames
+   * @param {Set<String>} possibleValues.passwords
+   */
+  promptToSavePassword(
+    aBrowser,
+    aLogin,
+    dismissed = false,
+    notifySaved = false,
+    autoFilledLoginGuid = "",
+    possibleValues = undefined
+  ) {
+    lazy.log.debug("Prompting user to save login.");
+    const inPrivateBrowsing = PrivateBrowsingUtils.isBrowserPrivate(aBrowser);
+    const notification = LoginManagerPrompter._showLoginCaptureDoorhanger(
+      aBrowser,
+      aLogin,
+      "password-save",
+      {
+        dismissed: inPrivateBrowsing || dismissed,
+        extraAttr: notifySaved ? "attention" : "",
+      },
+      possibleValues,
+      {
+        notifySaved,
+        autoFilledLoginGuid,
+      }
+    );
+    Services.obs.notifyObservers(aLogin, "passwordmgr-prompt-save");
+
+    return {
+      dismiss() {
+        const { PopupNotifications } = aBrowser.ownerGlobal.wrappedJSObject;
+        PopupNotifications.remove(notification);
+      },
+    };
+  }
+
+  /**
+   * Displays the PopupNotifications.sys.mjs doorhanger for password save or change.
+   *
+   * @param {Element} browser
+   *        The browser to show the doorhanger on.
+   * @param {nsILoginInfo} login
+   *        Login to save or change. For changes, this login should contain the
+   *        new password and/or username
+   * @param {string} type
+   *        This is "password-save" or "password-change" depending on the
+   *        original notification type. This is used for telemetry and tests.
+   * @param {object} showOptions
+   *        Options to pass along to PopupNotifications.show().
+   * @param {bool} [options.notifySaved = false]
+   *        Whether to indicate to the user that the login was already saved.
+   * @param {string} [options.messageStringID = undefined]
+   *        An optional string ID to override the default message.
+   * @param {string} [options.autoSavedLoginGuid = ""]
+   *        A string guid value for the auto-saved login to be removed if the changes
+   *        match it to a different login
+   * @param {string} [options.autoFilledLoginGuid = ""]
+   *        A string guid value for the autofilled login
+   * @param {object?} possibleValues
+   *                 Contains values from anything that we think, but are not sure, might be
+   *                 a username or password.  Has two properties, 'usernames' and 'passwords'.
+   * @param {Set<String>} possibleValues.usernames
+   * @param {Set<String>} possibleValues.passwords
+   */
+  static _showLoginCaptureDoorhanger(
+    browser,
+    login,
+    type,
+    showOptions = {},
+    possibleValues = undefined,
+    {
+      notifySaved = false,
+      messageStringID,
+      autoSavedLoginGuid = "",
+      autoFilledLoginGuid = "",
+    } = {}
+  ) {
+    lazy.log.debug(
+      `Got autoSavedLoginGuid: ${autoSavedLoginGuid} and autoFilledLoginGuid ${autoFilledLoginGuid}.`
+    );
+
+    const saveMessageIds = {
+      prompt: "password-manager-save-password-message",
+      mainButton: "password-manager-save-password-button-allow",
+      secondaryButton: "password-manager-save-password-button-deny",
+    };
+
+    const changeMessageIds = {
+      prompt: messageStringID ?? "password-manager-update-password-message",
+      mainButton: "password-manager-password-password-button-allow",
+      secondaryButton: "password-manager-update-password-button-deny",
+    };
+
+    const initialMessageIds =
+      type == "password-save" ? saveMessageIds : changeMessageIds;
+
+    const promptId = initialMessageIds.prompt;
+    const host = this._getShortDisplayHost(login.origin);
+    const promptMessage = lazy.l10n.formatValueSync(promptId, { host });
+
+    const histogramName =
+      type == "password-save"
+        ? "PWMGR_PROMPT_REMEMBER_ACTION"
+        : "PWMGR_PROMPT_UPDATE_ACTION";
+    const histogram = Services.telemetry.getHistogramById(histogramName);
+
+    const chromeDoc = browser.ownerDocument;
+    let currentNotification;
+
+    const wasModifiedEvent = {
+      // Values are mutated
+      did_edit_un: "false",
+      did_select_un: "false",
+      did_edit_pw: "false",
+      did_select_pw: "false",
+    };
+
+    const updateButtonStatus = element => {
+      const mainActionButton = element.button;
+      // Disable the main button inside the menu-button if the password field is empty.
+      if (!login.password.length) {
+        mainActionButton.setAttribute("disabled", true);
+        chromeDoc
+          .getElementById("password-notification-password")
+          .classList.add("popup-notification-invalid-input");
+      } else {
+        mainActionButton.removeAttribute("disabled");
+        chromeDoc
+          .getElementById("password-notification-password")
+          .classList.remove("popup-notification-invalid-input");
+      }
+    };
+
+    const updateButtonLabel = () => {
+      if (!currentNotification) {
+        console.error("updateButtonLabel, no currentNotification");
+      }
+      const foundLogins = lazy.LoginHelper.searchLoginsWithObject({
+        formActionOrigin: login.formActionOrigin,
+        origin: login.origin,
+        httpRealm: login.httpRealm,
+        schemeUpgrades: lazy.LoginHelper.schemeUpgrades,
+      });
+
+      const logins = this._filterUpdatableLogins(
+        login,
+        foundLogins,
+        autoSavedLoginGuid
+      );
+      const messageIds = !logins.length ? saveMessageIds : changeMessageIds;
+
+      // Update the label based on whether this will be a new login or not.
+
+      const mainButton = this.getLabelAndAccessKey(messageIds.mainButton);
+
+      // Update the labels for the next time the panel is opened.
+      currentNotification.mainAction.label = mainButton.label;
+      currentNotification.mainAction.accessKey = mainButton.accessKey;
+
+      // Update the labels in real time if the notification is displayed.
+      const element = [...currentNotification.owner.panel.childNodes].find(
+        n => n.notification == currentNotification
+      );
+      if (element) {
+        element.setAttribute("buttonlabel", mainButton.label);
+        element.setAttribute("buttonaccesskey", mainButton.accessKey);
+        updateButtonStatus(element);
+      }
+    };
+
+    const writeDataToUI = () => {
+      const nameField = chromeDoc.getElementById(
+        "password-notification-username"
+      );
+
+      nameField.placeholder = usernamePlaceholder;
+      nameField.value = login.username;
+
+      const toggleCheckbox = chromeDoc.getElementById(
+        "password-notification-visibilityToggle"
+      );
+      toggleCheckbox.removeAttribute("checked");
+      const passwordField = chromeDoc.getElementById(
+        "password-notification-password"
+      );
+      // Ensure the type is reset so the field is masked.
+      passwordField.type = "password";
+      passwordField.value = login.password;
+
+      updateButtonLabel();
+    };
+
+    const readDataFromUI = () => {
+      login.username = chromeDoc.getElementById(
+        "password-notification-username"
+      ).value;
+      login.password = chromeDoc.getElementById(
+        "password-notification-password"
+      ).value;
+    };
+
+    const onInput = () => {
+      readDataFromUI();
+      updateButtonLabel();
+    };
+
+    const onUsernameInput = () => {
+      wasModifiedEvent.did_edit_un = "true";
+      wasModifiedEvent.did_select_un = "false";
+      onInput();
+    };
+
+    const onUsernameSelect = () => {
+      wasModifiedEvent.did_edit_un = "false";
+      wasModifiedEvent.did_select_un = "true";
+    };
+
+    const onPasswordInput = () => {
+      wasModifiedEvent.did_edit_pw = "true";
+      wasModifiedEvent.did_select_pw = "false";
+      onInput();
+    };
+
+    const onPasswordSelect = () => {
+      wasModifiedEvent.did_edit_pw = "false";
+      wasModifiedEvent.did_select_pw = "true";
+    };
+
+    const onKeyUp = e => {
+      if (e.key == "Enter") {
+        e.target.closest("popupnotification").button.doCommand();
+      }
+    };
+
+    const onVisibilityToggle = commandEvent => {
+      const passwordField = chromeDoc.getElementById(
+        "password-notification-password"
+      );
+      // Gets the caret position before changing the type of the textbox
+      const selectionStart = passwordField.selectionStart;
+      const selectionEnd = passwordField.selectionEnd;
+      passwordField.setAttribute(
+        "type",
+        commandEvent.target.checked ? "" : "password"
+      );
+      if (!passwordField.hasAttribute("focused")) {
+        return;
+      }
+      passwordField.selectionStart = selectionStart;
+      passwordField.selectionEnd = selectionEnd;
+    };
+
+    const togglePopup = event => {
+      event.target.parentElement
+        .getElementsByClassName("ac-has-end-icon")[0]
+        .toggleHistoryPopup();
+    };
+
+    const persistData = async () => {
+      const foundLogins = lazy.LoginHelper.searchLoginsWithObject({
+        formActionOrigin: login.formActionOrigin,
+        origin: login.origin,
+        httpRealm: login.httpRealm,
+        schemeUpgrades: lazy.LoginHelper.schemeUpgrades,
+      });
+
+      let logins = this._filterUpdatableLogins(
+        login,
+        foundLogins,
+        autoSavedLoginGuid
+      );
+      const resolveBy = ["scheme", "timePasswordChanged"];
+      logins = lazy.LoginHelper.dedupeLogins(
+        logins,
+        ["username"],
+        resolveBy,
+        login.origin
+      );
+      // sort exact username matches to the top
+      logins.sort(l => (l.username == login.username ? -1 : 1));
+
+      lazy.log.debug(`Matched ${logins.length} logins.`);
+
+      let loginToRemove;
+      const loginToUpdate = logins.shift();
+
+      if (logins.length && logins[0].guid == autoSavedLoginGuid) {
+        loginToRemove = logins.shift();
+      }
+      if (logins.length) {
+        lazy.log.warn(
+          "persistData:",
+          logins.length,
+          "other updatable logins!",
+          logins.map(l => l.guid),
+          "loginToUpdate:",
+          loginToUpdate && loginToUpdate.guid,
+          "loginToRemove:",
+          loginToRemove && loginToRemove.guid
+        );
+        // Proceed with updating the login with the best username match rather
+        // than returning and losing the edit.
+      }
+
+      if (!loginToUpdate) {
+        // Create a new login, don't update an original.
+        // The original login we have been provided with might have its own
+        // metadata, but we don't want it propagated to the newly created one.
+        await Services.logins.addLoginAsync(
+          new LoginInfo(
+            login.origin,
+            login.formActionOrigin,
+            login.httpRealm,
+            login.username,
+            login.password,
+            login.usernameField,
+            login.passwordField
+          )
+        );
+      } else if (
+        loginToUpdate.password == login.password &&
+        loginToUpdate.username == login.username
+      ) {
+        // We only want to touch the login's use count and last used time.
+        lazy.log.debug(`Touch matched login: ${loginToUpdate.guid}.`);
+        Services.logins.recordPasswordUse(
+          loginToUpdate,
+          PrivateBrowsingUtils.isBrowserPrivate(browser),
+          loginToUpdate.username ? "form_password" : "form_login",
+          !!autoFilledLoginGuid
+        );
+      } else {
+        lazy.log.debug(`Update matched login: ${loginToUpdate.guid}.`);
+        this._updateLogin(loginToUpdate, login);
+        // notify that this auto-saved login has been merged
+        if (loginToRemove && loginToRemove.guid == autoSavedLoginGuid) {
+          Services.obs.notifyObservers(
+            loginToRemove,
+            "passwordmgr-autosaved-login-merged"
+          );
+        }
+      }
+
+      if (loginToRemove) {
+        lazy.log.debug(`Removing login ${loginToRemove.guid}.`);
+        Services.logins.removeLogin(loginToRemove);
+      }
+    };
+
+    const supportedHistogramNames = {
+      PWMGR_PROMPT_REMEMBER_ACTION: true,
+      PWMGR_PROMPT_UPDATE_ACTION: true,
+    };
+
+    const mainButton = this.getLabelAndAccessKey(initialMessageIds.mainButton);
+
+    // The main action is the "Save" or "Update" button.
+    const mainAction = {
+      label: mainButton.label,
+      accessKey: mainButton.accessKey,
+      callback: async () => {
+        const eventTypeMapping = {
+          "password-save": {
+            eventObject: "save",
+            confirmationHintFtlId: "confirmation-hint-password-created",
+          },
+          "password-change": {
+            eventObject: "update",
+            confirmationHintFtlId: "confirmation-hint-password-updated",
+          },
+        };
+
+        if (!eventTypeMapping[type]) {
+          throw new Error(`Unexpected doorhanger type: '${type}'`);
+        }
+
+        readDataFromUI();
+        if (
+          type == "password-save" &&
+          !Services.policies.isAllowed("removeMasterPassword")
+        ) {
+          if (!lazy.LoginHelper.isPrimaryPasswordSet()) {
+            browser.ownerGlobal.openDialog(
+              "chrome://mozapps/content/preferences/changemp.xhtml",
+              "",
+              "centerscreen,chrome,modal,titlebar"
+            );
+            if (!lazy.LoginHelper.isPrimaryPasswordSet()) {
+              return;
+            }
+          }
+        }
+        histogram.add(PROMPT_ADD_OR_UPDATE);
+        if (!supportedHistogramNames[histogramName]) {
+          throw new Error("Unknown histogram");
+        }
+
+        showConfirmation(browser, eventTypeMapping[type].confirmationHintFtlId);
+        // The popup does not wait until this promise is resolved, but is
+        // closed immediately when the function is returned. Therefore, we set
+        // the focus before awaiting the asynchronous operation.
+        browser.focus();
+        await persistData();
+
+        Services.telemetry.recordEvent(
+          "pwmgr",
+          "doorhanger_submitted",
+          eventTypeMapping[type].eventObject,
+          null,
+          wasModifiedEvent
+        );
+
+        if (histogramName == "PWMGR_PROMPT_REMEMBER_ACTION") {
+          Services.obs.notifyObservers(browser, "LoginStats:NewSavedPassword");
+        } else if (histogramName == "PWMGR_PROMPT_UPDATE_ACTION") {
+          Services.obs.notifyObservers(browser, "LoginStats:LoginUpdateSaved");
+        }
+
+        Services.obs.notifyObservers(
+          null,
+          "weave:telemetry:histogram",
+          histogramName
+        );
+      },
+    };
+
+    const secondaryButton = this.getLabelAndAccessKey(
+      initialMessageIds.secondaryButton
+    );
+
+    const secondaryActions = [
+      {
+        label: secondaryButton.label,
+        accessKey: secondaryButton.accessKey,
+        callback: () => {
+          histogram.add(PROMPT_NOTNOW_OR_DONTUPDATE);
+          Services.obs.notifyObservers(
+            null,
+            "weave:telemetry:histogram",
+            histogramName
+          );
+          browser.focus();
+        },
+      },
+    ];
+    // Include a "Never for this site" button when saving a new password.
+    if (type == "password-save") {
+      const neverSaveButton = this.getLabelAndAccessKey(
+        "password-manager-save-password-button-never"
+      );
+      secondaryActions.push({
+        label: neverSaveButton.label,
+        accessKey: neverSaveButton.accessKey,
+        callback: () => {
+          histogram.add(PROMPT_NEVER);
+          Services.obs.notifyObservers(
+            null,
+            "weave:telemetry:histogram",
+            histogramName
+          );
+          Services.logins.setLoginSavingEnabled(login.origin, false);
+          browser.focus();
+        },
+      });
+    }
+
+    const updatePasswordButtonDelete = this.getLabelAndAccessKey(
+      "password-manager-update-password-button-delete"
+    );
+
+    // Include a "Delete this login" button when updating an existing password
+    if (type == "password-change") {
+      secondaryActions.push({
+        label: updatePasswordButtonDelete.label,
+        accessKey: updatePasswordButtonDelete.accessKey,
+        callback: async () => {
+          histogram.add(PROMPT_DELETE);
+          Services.obs.notifyObservers(
+            null,
+            "weave:telemetry:histogram",
+            histogramName
+          );
+          const matchingLogins = await Services.logins.searchLoginsAsync({
+            guid: login.guid,
+            origin: login.origin,
+          });
+          Services.logins.removeLogin(matchingLogins[0]);
+          browser.focus();
+          lazy.log.debug("Showing the ConfirmationHint");
+          showConfirmation(browser, "confirmation-hint-password-removed");
+        },
+      });
+    }
+
+    const usernamePlaceholder = lazy.l10n.formatValueSync(
+      "password-manager-no-username-placeholder"
+    );
+    const togglePassword = this.getLabelAndAccessKey(
+      "password-manager-toggle-password"
+    );
+
+    // .wrappedJSObject needed here -- see bug 422974 comment 5.
+    const { PopupNotifications } = browser.ownerGlobal.wrappedJSObject;
+
+    const notificationID = "password";
+    // keep attention notifications around for longer after a locationchange
+    const timeoutMs =
+      showOptions.dismissed && showOptions.extraAttr == "attention"
+        ? ATTENTION_NOTIFICATION_TIMEOUT_MS
+        : NOTIFICATION_TIMEOUT_MS;
+
+    const options = Object.assign(
+      {
+        timeout: Date.now() + timeoutMs,
+        persistWhileVisible: true,
+        passwordNotificationType: type,
+        hideClose: true,
+        eventCallback(topic) {
+          switch (topic) {
+            case "showing":
+              lazy.log.debug("showing");
+              currentNotification = this;
+
+              // Record the first time this instance of the doorhanger is shown.
+              if (!this.timeShown) {
+                histogram.add(PROMPT_DISPLAYED);
+                Services.obs.notifyObservers(
+                  null,
+                  "weave:telemetry:histogram",
+                  histogramName
+                );
+              }
+
+              chromeDoc
+                .getElementById("password-notification-password")
+                .removeAttribute("focused");
+              chromeDoc
+                .getElementById("password-notification-username")
+                .removeAttribute("focused");
+              chromeDoc
+                .getElementById("password-notification-username")
+                .addEventListener("input", onUsernameInput);
+              chromeDoc
+                .getElementById("password-notification-username")
+                .addEventListener("keyup", onKeyUp);
+              chromeDoc
+                .getElementById("password-notification-password")
+                .addEventListener("keyup", onKeyUp);
+              chromeDoc
+                .getElementById("password-notification-password")
+                .addEventListener("input", onPasswordInput);
+              chromeDoc
+                .getElementById("password-notification-username-dropmarker")
+                .addEventListener("click", togglePopup);
+
+              LoginManagerPrompter._getUsernameSuggestions(
+                login,
+                possibleValues?.usernames
+              ).then(usernameSuggestions => {
+                const dropmarker = chromeDoc?.getElementById(
+                  "password-notification-username-dropmarker"
+                );
+                if (dropmarker) {
+                  dropmarker.hidden = !usernameSuggestions.length;
+                }
+
+                const usernameField = chromeDoc?.getElementById(
+                  "password-notification-username"
+                );
+                if (usernameField) {
+                  usernameField.classList.toggle(
+                    "ac-has-end-icon",
+                    !!usernameSuggestions.length
+                  );
+                }
+              });
+
+              const toggleBtn = chromeDoc.getElementById(
+                "password-notification-visibilityToggle"
+              );
+
+              if (
+                Services.prefs.getBoolPref(
+                  "signon.rememberSignons.visibilityToggle"
+                )
+              ) {
+                toggleBtn.addEventListener("command", onVisibilityToggle);
+
+                toggleBtn.setAttribute("label", togglePassword.label);
+                toggleBtn.setAttribute("accesskey", togglePassword.accessKey);
+
+                const hideToggle =
+                  lazy.LoginHelper.isPrimaryPasswordSet() ||
+                  // Don't show the toggle when the login was autofilled
+                  !!autoFilledLoginGuid ||
+                  // Dismissed-by-default prompts should still show the toggle.
+                  (this.timeShown && this.wasDismissed) ||
+                  // If we are only adding a username then the password is
+                  // one that is already saved and we don't want to reveal
+                  // it as the submitter of this form may not be the account
+                  // owner, they may just be using the saved password.
+                  (messageStringID ==
+                    "password-manager-update-login-add-username" &&
+                    login.timePasswordChanged <
+                      Date.now() - VISIBILITY_TOGGLE_MAX_PW_AGE_MS);
+                toggleBtn.hidden = hideToggle;
+              }
+
+              let popup = chromeDoc.getElementById("PopupAutoComplete");
+              popup.onUsernameSelect = onUsernameSelect;
+              popup.onPasswordSelect = onPasswordSelect;
+
+              LoginManagerPrompter._setUsernameAutocomplete(
+                login,
+                possibleValues?.usernames
+              );
+
+              break;
+            case "shown": {
+              lazy.log.debug("shown");
+              writeDataToUI();
+              const anchorIcon = this.anchorElement;
+              if (anchorIcon && this.options.extraAttr == "attention") {
+                anchorIcon.removeAttribute("extraAttr");
+                delete this.options.extraAttr;
+              }
+              break;
+            }
+            case "dismissed":
+              // Note that this can run after `showing` but before `shown` upon tab switch.
+              this.wasDismissed = true;
+            // Fall through.
+            case "removed": {
+              // Note that this can run after `showing` and `shown` for the
+              // notification it's replacing.
+              lazy.log.debug(topic);
+              currentNotification = null;
+
+              const usernameField = chromeDoc.getElementById(
+                "password-notification-username"
+              );
+              usernameField.removeEventListener("input", onUsernameInput);
+              usernameField.removeEventListener("keyup", onKeyUp);
+              const passwordField = chromeDoc.getElementById(
+                "password-notification-password"
+              );
+              passwordField.removeEventListener("input", onPasswordInput);
+              passwordField.removeEventListener("keyup", onKeyUp);
+              passwordField.removeEventListener("command", onVisibilityToggle);
+              chromeDoc
+                .getElementById("password-notification-username-dropmarker")
+                .removeEventListener("click", togglePopup);
+              break;
+            }
+          }
+          return false;
+        },
+      },
+      showOptions
+    );
+
+    const notification = PopupNotifications.show(
+      browser,
+      notificationID,
+      promptMessage,
+      "password-notification-icon",
+      mainAction,
+      secondaryActions,
+      options
+    );
+
+    if (notifySaved) {
+      showConfirmation(
+        browser,
+        "confirmation-hint-password-created",
+        "password-notification-icon"
+      );
+    }
+
+    return notification;
+  }
+
+  /**
+   * Called when we think we detect a password or username change for
+   * an existing login, when the form being submitted contains multiple
+   * password fields.
+   *
+   * @param {Element} aBrowser
+   *                  The browser element that the request came from.
+   * @param {nsILoginInfo} aOldLogin
+   *                       The old login we may want to update.
+   * @param {nsILoginInfo} aNewLogin
+   *                       The new login from the page form.
+   * @param {boolean} [dismissed = false]
+   *                  If the prompt should be automatically dismissed on being shown.
+   * @param {boolean} [notifySaved = false]
+   *                  Whether the notification should indicate that a login has been saved
+   * @param {string} [autoSavedLoginGuid = ""]
+   *                 A guid value for the old login to be removed if the changes match it
+   *                 to a different login
+   * @param {object?} possibleValues
+   *                 Contains values from anything that we think, but are not sure, might be
+   *                 a username or password.  Has two properties, 'usernames' and 'passwords'.
+   * @param {Set<String>} possibleValues.usernames
+   * @param {Set<String>} possibleValues.passwords
+   */
+  promptToChangePassword(
+    aBrowser,
+    aOldLogin,
+    aNewLogin,
+    dismissed = false,
+    notifySaved = false,
+    autoSavedLoginGuid = "",
+    autoFilledLoginGuid = "",
+    possibleValues = undefined
+  ) {
+    const login = aOldLogin.clone();
+    login.origin = aNewLogin.origin;
+    login.formActionOrigin = aNewLogin.formActionOrigin;
+    login.password = aNewLogin.password;
+    login.username = aNewLogin.username;
+
+    let messageStringID;
+    if (
+      aOldLogin.username === "" &&
+      login.username !== "" &&
+      login.password == aOldLogin.password
+    ) {
+      // If the saved password matches the password we're prompting with then we
+      // are only prompting to let the user add a username since there was one in
+      // the form. Change the message so the purpose of the prompt is clearer.
+      messageStringID = "password-manager-update-login-add-username";
+    }
+
+    const notification = LoginManagerPrompter._showLoginCaptureDoorhanger(
+      aBrowser,
+      login,
+      "password-change",
+      {
+        dismissed,
+        extraAttr: notifySaved ? "attention" : "",
+      },
+      possibleValues,
+      {
+        notifySaved,
+        messageStringID,
+        autoSavedLoginGuid,
+        autoFilledLoginGuid,
+      }
+    );
+
+    const oldGUID = aOldLogin.QueryInterface(Ci.nsILoginMetaInfo).guid;
+    Services.obs.notifyObservers(
+      aNewLogin,
+      "passwordmgr-prompt-change",
+      oldGUID
+    );
+
+    return {
+      dismiss() {
+        const { PopupNotifications } = aBrowser.ownerGlobal.wrappedJSObject;
+        PopupNotifications.remove(notification);
+      },
+    };
+  }
+
+  /**
+   * Called when we detect a password change in a form submission, but we
+   * don't know which existing login (username) it's for. Asks the user
+   * to select a username and confirm the password change.
+   *
+   * Note: The caller doesn't know the username for aNewLogin, so this
+   *       function fills in .username and .usernameField with the values
+   *       from the login selected by the user.
+   */
+  promptToChangePasswordWithUsernames(browser, logins, aNewLogin) {
+    lazy.log.debug(
+      `Prompting user to change passowrd for username with count: ${logins.length}.`
+    );
+
+    const noUsernamePlaceholder = lazy.l10n.formatValueSync(
+      "password-manager-no-username-placeholder"
+    );
+    const usernames = logins.map(l => l.username || noUsernamePlaceholder);
+    const dialogText = lazy.l10n.formatValueSync(
+      "password-manager-select-username"
+    );
+    const dialogTitle = lazy.l10n.formatValueSync(
+      "password-manager-confirm-password-change"
+    );
+    const selectedIndex = { value: null };
+
+    // If user selects ok, outparam.value is set to the index
+    // of the selected username.
+    const ok = Services.prompt.select(
+      browser.ownerGlobal,
+      dialogTitle,
+      dialogText,
+      usernames,
+      selectedIndex
+    );
+    if (ok) {
+      // Now that we know which login to use, modify its password.
+      const selectedLogin = logins[selectedIndex.value];
+      lazy.log.debug(`Updating password for origin: ${aNewLogin.origin}.`);
+      const newLoginWithUsername = Cc[
+        "@mozilla.org/login-manager/loginInfo;1"
+      ].createInstance(Ci.nsILoginInfo);
+      newLoginWithUsername.init(
+        aNewLogin.origin,
+        aNewLogin.formActionOrigin,
+        aNewLogin.httpRealm,
+        selectedLogin.username,
+        aNewLogin.password,
+        selectedLogin.usernameField,
+        aNewLogin.passwordField
+      );
+      LoginManagerPrompter._updateLogin(selectedLogin, newLoginWithUsername);
+    }
+  }
+
+  /* ---------- Internal Methods ---------- */
+
+  /**
+   * Helper method to update and persist an existing nsILoginInfo object with new property values.
+   */
+  static _updateLogin(login, aNewLogin) {
+    const now = Date.now();
+    const propBag = Cc["@mozilla.org/hash-property-bag;1"].createInstance(
+      Ci.nsIWritablePropertyBag
+    );
+    propBag.setProperty("formActionOrigin", aNewLogin.formActionOrigin);
+    propBag.setProperty("origin", aNewLogin.origin);
+    propBag.setProperty("password", aNewLogin.password);
+    propBag.setProperty("username", aNewLogin.username);
+    // Explicitly set the password change time here (even though it would
+    // be changed automatically), to ensure that it's exactly the same
+    // value as timeLastUsed.
+    propBag.setProperty("timePasswordChanged", now);
+    propBag.setProperty("timeLastUsed", now);
+    propBag.setProperty("timesUsedIncrement", 1);
+    // Note that we don't call `recordPasswordUse` so telemetry won't record a
+    // use in this case though that is normally correct since we would instead
+    // record the save/update in a separate probe and recording it in both would
+    // be wrong.
+    Services.logins.modifyLogin(login, propBag);
+  }
+
+  /**
+   * Retrieves the message of the given id from fluent
+   * and extracts the label and accesskey
+   *
+   * @param {String} id message id
+   * @returns label and accesskey
+   */
+  static getLabelAndAccessKey(id) {
+    const msg = lazy.l10n.formatMessagesSync([id])[0];
+    return {
+      label: msg.attributes.find(x => x.name == "label").value,
+      accessKey: msg.attributes.find(x => x.name == "accesskey").value,
+    };
+  }
+
+  /**
+   * Converts a login's origin field to a short string for
+   * prompting purposes. Eg, "http://foo.com" --> "foo.com", or
+   * "ftp://www.site.co.uk" --> "site.co.uk".
+   */
+  static _getShortDisplayHost(aURIString) {
+    let displayHost;
+
+    const idnService = Cc["@mozilla.org/network/idn-service;1"].getService(
+      Ci.nsIIDNService
+    );
+    try {
+      const uri = Services.io.newURI(aURIString);
+      const baseDomain = Services.eTLD.getBaseDomain(uri);
+      displayHost = idnService.convertToDisplayIDN(baseDomain, {});
+    } catch (e) {
+      lazy.log.warn(`Couldn't process supplied URIString: ${aURIString}`);
+    }
+
+    if (!displayHost) {
+      displayHost = aURIString;
+    }
+
+    return displayHost;
+  }
+
+  /**
+   * This function looks for existing logins that can be updated
+   * to match a submitted login, instead of creating a new one.
+   *
+   * Given a login and a loginList, it filters the login list
+   * to find every login with either:
+   * - the same username as aLogin
+   * - the same password as aLogin and an empty username
+   *   so the user can add a username.
+   * - the same guid as the given login when it has an empty username
+   *
+   * @param {nsILoginInfo} aLogin
+   *                       login to use as filter.
+   * @param {nsILoginInfo[]} aLoginList
+   *                         Array of logins to filter.
+   * @param {String} includeGUID
+   *                 guid value for login that not be filtered out
+   * @returns {nsILoginInfo[]} the filtered array of logins.
+   */
+  static _filterUpdatableLogins(aLogin, aLoginList, includeGUID) {
+    return aLoginList.filter(
+      l =>
+        l.username == aLogin.username ||
+        (l.password == aLogin.password && !l.username) ||
+        (includeGUID && includeGUID == l.guid)
+    );
+  }
+
+  /**
+   * Set the values that will be used the next time the username autocomplete popup is opened.
+   *
+   * @param {nsILoginInfo} login - used only for its information about the current domain.
+   * @param {Set<String>?} possibleUsernames - values that we believe may be new/changed login usernames.
+   */
+  static async _setUsernameAutocomplete(login, possibleUsernames = new Set()) {
+    const result = Cc[
+      "@mozilla.org/autocomplete/simple-result;1"
+    ].createInstance(Ci.nsIAutoCompleteSimpleResult);
+    result.setDefaultIndex(0);
+
+    const usernames = await this._getUsernameSuggestions(
+      login,
+      possibleUsernames
+    );
+    for (const { text, style } of usernames) {
+      const value = text;
+      const comment = "";
+      const image = "";
+      const _style = style;
+      result.appendMatch(value, comment, image, _style);
+    }
+
+    result.setSearchResult(
+      usernames.length
+        ? Ci.nsIAutoCompleteResult.RESULT_SUCCESS
+        : Ci.nsIAutoCompleteResult.RESULT_NOMATCH
+    );
+
+    lazy.usernameAutocompleteSearch.overrideNextResult(result);
+  }
+
+  /**
+   * @param {nsILoginInfo} login - used only for its information about the current domain.
+   * @param {Set<String>?} possibleUsernames - values that we believe may be new/changed login usernames.
+   *
+   * @returns {object[]} an ordered list of usernames to be used the next time the username autocomplete popup is opened.
+   */
+  static async _getUsernameSuggestions(login, possibleUsernames = new Set()) {
+    if (!Services.prefs.getBoolPref("signon.capture.inputChanges.enabled")) {
+      return [];
+    }
+
+    // Don't reprompt for Primary Password, as we already prompted at least once
+    // to show the doorhanger if it is locked
+    if (!Services.logins.isLoggedIn) {
+      return [];
+    }
+
+    const baseDomainLogins = await Services.logins.searchLoginsAsync({
+      origin: login.origin,
+      schemeUpgrades: lazy.LoginHelper.schemeUpgrades,
+      acceptDifferentSubdomains: true,
+    });
+
+    const saved = baseDomainLogins.map(login => {
+      return { text: login.username, style: "login" };
+    });
+    const possible = [...possibleUsernames].map(username => {
+      return { text: username, style: "possible-username" };
+    });
+
+    return possible
+      .concat(saved)
+      .reduce((acc, next) => {
+        const alreadyInAcc =
+          acc.findIndex(entry => entry.text == next.text) != -1;
+        if (!alreadyInAcc) {
+          acc.push(next);
+        } else if (next.style == "possible-username") {
+          const existingIndex = acc.findIndex(entry => entry.text == next.text);
+          acc[existingIndex] = next;
+        }
+        return acc;
+      }, [])
+      .filter(suggestion => !!suggestion.text);
+  }
+}
+
+// Add this observer once for the process.
+Services.obs.addObserver(observer, "autocomplete-did-enter-text");
+
+ChromeUtils.defineLazyGetter(lazy, "log", () => {
+  return lazy.LoginHelper.createLogger("LoginManagerPrompter");
+});
diff --git a/toolkit/components/passwordmgr/LoginManagerTelemetry.sys.mjs b/toolkit/components/passwordmgr/LoginManagerTelemetry.sys.mjs
new file mode 100644
index 0000000000..ad2e7d80d3
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginManagerTelemetry.sys.mjs
@@ -0,0 +1,54 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Provides the logic for recording all password manager related telemetry data.
+ */
+export class LoginManagerTelemetry {
+  static recordAutofillResult(result) {
+    Glean.pwmgr.formAutofillResult[result].add(1);
+    LoginManagerLegacyTelemetry.recordAutofillResult(result);
+  }
+}
+
+/**
+ * Until the password manager related measurements are fully migrated to Glean,
+ * we need to collect the data in both systems (Legacy Telemetry and Glean) for now.
+ * Not all new Glean metric can be mirrored automatically (using the property telemetry_mirror in metrics.yaml).
+ * Therefore, we need to manually call the Legacy Telemetry API calls in this class.
+ * Once we have collected enough data for all probes in the Glean system, we can remove this class and its references.
+ */
+class LoginManagerLegacyTelemetry {
+  static HISTOGRAM_AUTOFILL_RESULT = "PWMGR_FORM_AUTOFILL_RESULT";
+  static AUTOFILL_RESULT = {
+    filled: 0,
+    no_password_field: 1,
+    password_disabled_readonly: 2,
+    no_logins_fit: 3,
+    no_saved_logins: 4,
+    existing_password: 5,
+    existing_username: 6,
+    multiple_logins: 7,
+    no_autofill_forms: 8,
+    autocomplete_off: 9,
+    insecure: 10,
+    password_autocomplete_new_password: 11,
+    type_no_longer_password: 12,
+    form_in_crossorigin_subframe: 13,
+    filled_username_only_form: 14,
+  };
+
+  static convertToAutofillResultNumber(result) {
+    return LoginManagerLegacyTelemetry.AUTOFILL_RESULT[result];
+  }
+
+  static recordAutofillResult(result) {
+    const autofillResultNumber =
+      LoginManagerLegacyTelemetry.convertToAutofillResultNumber(result);
+    Services.telemetry
+      .getHistogramById(LoginManagerLegacyTelemetry.HISTOGRAM_AUTOFILL_RESULT)
+      .add(autofillResultNumber);
+  }
+}
+export default LoginManagerTelemetry;
diff --git a/toolkit/components/passwordmgr/LoginRecipes.sys.mjs b/toolkit/components/passwordmgr/LoginRecipes.sys.mjs
new file mode 100644
index 0000000000..66d7bf80bd
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginRecipes.sys.mjs
@@ -0,0 +1,381 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const REQUIRED_KEYS = ["hosts"];
+const OPTIONAL_KEYS = [
+  "description",
+  "notPasswordSelector",
+  "notUsernameSelector",
+  "passwordSelector",
+  "pathRegex",
+  "usernameSelector",
+  "schema",
+  "id",
+  "last_modified",
+];
+const SUPPORTED_KEYS = REQUIRED_KEYS.concat(OPTIONAL_KEYS);
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+  RemoteSettings: "resource://services-settings/remote-settings.sys.mjs",
+});
+
+ChromeUtils.defineLazyGetter(lazy, "log", () =>
+  lazy.LoginHelper.createLogger("LoginRecipes")
+);
+
+/**
+ * Create an instance of the object to manage recipes in the parent process.
+ * Consumers should wait until {@link initializationPromise} resolves before
+ * calling methods on the object.
+ *
+ * @constructor
+ * @param {String} [aOptions.defaults=null] the URI to load the recipes from.
+ *                                          If it's null, nothing is loaded.
+ *
+ */
+export function LoginRecipesParent(aOptions = { defaults: null }) {
+  if (Services.appinfo.processType != Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT) {
+    throw new Error(
+      "LoginRecipesParent should only be used from the main process"
+    );
+  }
+  this._defaults = aOptions.defaults;
+  this.reset();
+}
+
+LoginRecipesParent.prototype = {
+  /**
+   * Promise resolved with an instance of itself when the module is ready.
+   *
+   * @type {Promise}
+   */
+  initializationPromise: null,
+
+  /**
+   * @type {bool} Whether default recipes were loaded at construction time.
+   */
+  _defaults: null,
+
+  /**
+   * @type {Map} Map of hosts (including non-default port numbers) to Sets of recipes.
+   *             e.g. "example.com:8080" => Set({...})
+   */
+  _recipesByHost: null,
+
+  /**
+   * @type {Object} Instance of Remote Settings client that has access to the
+   *                "password-recipes" collection
+   */
+  _rsClient: null,
+
+  /**
+   * @param {Object} aRecipes an object containing recipes to load for use. The object
+   *                          should be compatible with JSON (e.g. no RegExp).
+   * @return {Promise} resolving when the recipes are loaded
+   */
+  load(aRecipes) {
+    let recipeErrors = 0;
+    for (let rawRecipe of aRecipes.siteRecipes) {
+      try {
+        rawRecipe.pathRegex = rawRecipe.pathRegex
+          ? new RegExp(rawRecipe.pathRegex)
+          : undefined;
+        this.add(rawRecipe);
+      } catch (e) {
+        recipeErrors++;
+        lazy.log.error("Error loading recipe.", rawRecipe, e);
+      }
+    }
+    if (recipeErrors) {
+      return Promise.reject(`There were ${recipeErrors} recipe error(s)`);
+    }
+    return Promise.resolve();
+  },
+
+  /**
+   * Reset the set of recipes to the ones from the time of construction.
+   */
+  reset() {
+    lazy.log.debug("Resetting recipes with defaults:", this._defaults);
+    this._recipesByHost = new Map();
+    if (this._defaults) {
+      let initPromise;
+      /**
+       * Both branches rely on a JSON dump of the Remote Settings collection, packaged both in Desktop and Android.
+       * The «legacy» mode will read the dump directly from the packaged resources.
+       * With Remote Settings, the dump is used to initialize the local database without network,
+       * and the list of password recipes can be refreshed without restarting and without software update.
+       */
+      if (lazy.LoginHelper.remoteRecipesEnabled) {
+        if (!this._rsClient) {
+          this._rsClient = lazy.RemoteSettings(
+            lazy.LoginHelper.remoteRecipesCollection
+          );
+          // Set up sync observer to update local recipes from Remote Settings recipes
+          this._rsClient.on("sync", event => this.onRemoteSettingsSync(event));
+        }
+        initPromise = this._rsClient.get();
+      } else if (this._defaults.startsWith("resource://")) {
+        initPromise = fetch(this._defaults)
+          .then(resp => resp.json())
+          .then(({ data }) => data);
+      } else {
+        lazy.log.error(
+          "Invalid recipe path found, setting empty recipes list!"
+        );
+        initPromise = new Promise(() => []);
+      }
+      this.initializationPromise = initPromise.then(async siteRecipes => {
+        Services.ppmm.broadcastAsyncMessage("clearRecipeCache");
+        await this.load({ siteRecipes });
+        return this;
+      });
+    } else {
+      this.initializationPromise = Promise.resolve(this);
+    }
+  },
+
+  /**
+   * Validate the recipe is sane and then add it to the set of recipes.
+   *
+   * @param {Object} recipe
+   */
+  add(recipe) {
+    let recipeKeys = Object.keys(recipe);
+    let unknownKeys = recipeKeys.filter(key => !SUPPORTED_KEYS.includes(key));
+    if (unknownKeys.length) {
+      throw new Error(
+        "The following recipe keys aren't supported: " + unknownKeys.join(", ")
+      );
+    }
+
+    let missingRequiredKeys = REQUIRED_KEYS.filter(
+      key => !recipeKeys.includes(key)
+    );
+    if (missingRequiredKeys.length) {
+      throw new Error(
+        "The following required recipe keys are missing: " +
+          missingRequiredKeys.join(", ")
+      );
+    }
+
+    if (!Array.isArray(recipe.hosts)) {
+      throw new Error("'hosts' must be a array");
+    }
+
+    if (!recipe.hosts.length) {
+      throw new Error("'hosts' must be a non-empty array");
+    }
+
+    if (recipe.pathRegex && recipe.pathRegex.constructor.name != "RegExp") {
+      throw new Error("'pathRegex' must be a regular expression");
+    }
+
+    const OPTIONAL_STRING_PROPS = [
+      "description",
+      "passwordSelector",
+      "usernameSelector",
+    ];
+    for (let prop of OPTIONAL_STRING_PROPS) {
+      if (recipe[prop] && typeof recipe[prop] != "string") {
+        throw new Error(`'${prop}' must be a string`);
+      }
+    }
+
+    // Add the recipe to the map for each host
+    for (let host of recipe.hosts) {
+      if (!this._recipesByHost.has(host)) {
+        this._recipesByHost.set(host, new Set());
+      }
+      this._recipesByHost.get(host).add(recipe);
+    }
+  },
+
+  /**
+   * Currently only exact host matches are returned but this will eventually handle parent domains.
+   *
+   * @param {String} aHost (e.g. example.com:8080 [non-default port] or sub.example.com)
+   * @return {Set} of recipes that apply to the host ordered by host priority
+   */
+  getRecipesForHost(aHost) {
+    let hostRecipes = this._recipesByHost.get(aHost);
+    if (!hostRecipes) {
+      return new Set();
+    }
+
+    return hostRecipes;
+  },
+
+  /**
+   * Handles the Remote Settings sync event for the "password-recipes" collection.
+   *
+   * @param {Object} aEvent
+   * @param {Array} event.current Records in the "password-recipes" collection after the sync event
+   * @param {Array} event.created Records that were created with this particular sync
+   * @param {Array} event.updated Records that were updated with this particular sync
+   * @param {Array} event.deleted Records that were deleted with this particular sync
+   */
+  onRemoteSettingsSync(aEvent) {
+    this._recipesByHost = new Map();
+    let {
+      data: { current },
+    } = aEvent;
+    let recipes = {
+      siteRecipes: current,
+    };
+    Services.ppmm.broadcastAsyncMessage("clearRecipeCache");
+    this.load(recipes);
+  },
+};
+
+export const LoginRecipesContent = {
+  _recipeCache: new WeakMap(),
+
+  _clearRecipeCache() {
+    lazy.log.debug("Clearing recipe cache.");
+    this._recipeCache = new WeakMap();
+  },
+
+  /**
+   * Locally caches recipes for a given host.
+   *
+   * @param {String} aHost (e.g. example.com:8080 [non-default port] or sub.example.com)
+   * @param {Object} win - the window of the host
+   * @param {Set} recipes - recipes that apply to the host
+   */
+  cacheRecipes(aHost, win, recipes) {
+    let recipeMap = this._recipeCache.get(win);
+
+    if (!recipeMap) {
+      recipeMap = new Map();
+      this._recipeCache.set(win, recipeMap);
+    }
+
+    recipeMap.set(aHost, recipes);
+  },
+
+  /**
+   * Tries to fetch recipes for a given host, using a local cache if possible.
+   * Otherwise, the recipes are cached for later use.
+   *
+   * @param {String} aHost (e.g. example.com:8080 [non-default port] or sub.example.com)
+   * @param {Object} win - the window of the host
+   * @return {Set} of recipes that apply to the host
+   */
+  getRecipes(aHost, win) {
+    let recipes;
+    const recipeMap = this._recipeCache.get(win);
+
+    if (recipeMap) {
+      recipes = recipeMap.get(aHost);
+
+      if (recipes) {
+        return recipes;
+      }
+    }
+
+    if (!Cu.isInAutomation) {
+      // this is a blocking call we expect in tests and rarely expect in
+      // production, for example when Remote Settings are updated.
+      lazy.log.warn(`Falling back to a synchronous message for: ${aHost}.`);
+    }
+    recipes = Services.cpmm.sendSyncMessage("PasswordManager:findRecipes", {
+      formOrigin: aHost,
+    })[0];
+    this.cacheRecipes(aHost, win, recipes);
+
+    return recipes;
+  },
+
+  /**
+   * @param {Set} aRecipes - Possible recipes that could apply to the form
+   * @param {FormLike} aForm - We use a form instead of just a URL so we can later apply
+   * tests to the page contents.
+   * @return {Set} a subset of recipes that apply to the form with the order preserved
+   */
+  _filterRecipesForForm(aRecipes, aForm) {
+    let formDocURL = aForm.ownerDocument.location;
+    let hostRecipes = aRecipes;
+    let recipes = new Set();
+    if (!hostRecipes) {
+      return recipes;
+    }
+
+    for (let hostRecipe of hostRecipes) {
+      if (
+        hostRecipe.pathRegex &&
+        !hostRecipe.pathRegex.test(formDocURL.pathname)
+      ) {
+        continue;
+      }
+      recipes.add(hostRecipe);
+    }
+
+    return recipes;
+  },
+
+  /**
+   * Given a set of recipes that apply to the host, choose the one most applicable for
+   * overriding login fields in the form.
+   *
+   * @param {Set} aRecipes The set of recipes to consider for the form
+   * @param {FormLike} aForm The form where login fields exist.
+   * @return {Object} The recipe that is most applicable for the form.
+   */
+  getFieldOverrides(aRecipes, aForm) {
+    let recipes = this._filterRecipesForForm(aRecipes, aForm);
+    lazy.log.debug(`Filtered recipes size: ${recipes.size}.`);
+    if (!recipes.size) {
+      return null;
+    }
+
+    let chosenRecipe = null;
+    // Find the first (most-specific recipe that involves field overrides).
+    for (let recipe of recipes) {
+      if (
+        !recipe.usernameSelector &&
+        !recipe.passwordSelector &&
+        !recipe.notUsernameSelector &&
+        !recipe.notPasswordSelector
+      ) {
+        continue;
+      }
+
+      chosenRecipe = recipe;
+      break;
+    }
+
+    return chosenRecipe;
+  },
+
+  /**
+   * @param {HTMLElement} aParent the element to query for the selector from.
+   * @param {CSSSelector} aSelector the CSS selector to query for the login field.
+   * @return {HTMLElement|null}
+   */
+  queryLoginField(aParent, aSelector) {
+    if (!aSelector) {
+      return null;
+    }
+    let field = aParent.ownerDocument.querySelector(aSelector);
+    if (!field) {
+      lazy.log.debug(`Login field selector wasn't matched: ${aSelector}.`);
+      return null;
+    }
+    // ownerGlobal doesn't exist in content privileged windows.
+    if (
+      // eslint-disable-next-line mozilla/use-ownerGlobal
+      !aParent.ownerDocument.defaultView.HTMLInputElement.isInstance(field)
+    ) {
+      lazy.log.warn(
+        `Login field with selector ${aSelector} isn't an <input> so ignoring it.`
+      );
+      return null;
+    }
+    return field;
+  },
+};
diff --git a/toolkit/components/passwordmgr/LoginRelatedRealms.sys.mjs b/toolkit/components/passwordmgr/LoginRelatedRealms.sys.mjs
new file mode 100644
index 0000000000..6ab9ca8642
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginRelatedRealms.sys.mjs
@@ -0,0 +1,108 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+  RemoteSettings: "resource://services-settings/remote-settings.sys.mjs",
+});
+
+ChromeUtils.defineLazyGetter(lazy, "log", () => {
+  let logger = lazy.LoginHelper.createLogger("LoginRelatedRealms");
+  return logger;
+});
+
+export class LoginRelatedRealmsParent extends JSWindowActorParent {
+  /**
+   * @type RemoteSettingsClient
+   *
+   * @memberof LoginRelatedRealmsParent
+   */
+  _sharedCredentialsClient = null;
+  /**
+   * @type string[][]
+   *
+   * @memberof LoginRelatedRealmsParent
+   */
+  _relatedDomainsList = [[]];
+
+  /**
+   * Handles the Remote Settings sync event
+   *
+   * @param {Object} aEvent
+   * @param {Array} aEvent.current Records that are currently in the collection after the sync event
+   * @param {Array} aEvent.created Records that were created
+   * @param {Array} aEvent.updated Records that were updated
+   * @param {Array} aEvent.deleted Records that were deleted
+   * @memberof LoginRelatedRealmsParent
+   */
+  onRemoteSettingsSync(aEvent) {
+    let {
+      data: { current },
+    } = aEvent;
+    this._relatedDomainsList = current;
+  }
+
+  async getSharedCredentialsCollection() {
+    if (!this._sharedCredentialsClient) {
+      this._sharedCredentialsClient = lazy.RemoteSettings(
+        lazy.LoginHelper.relatedRealmsCollection
+      );
+      this._sharedCredentialsClient.on("sync", event =>
+        this.onRemoteSettingsSync(event)
+      );
+      this._relatedDomainsList = await this._sharedCredentialsClient.get();
+    }
+    return this._relatedDomainsList;
+  }
+
+  /**
+   * Determine if there are any related realms of this `formOrigin` using the related realms collection
+   * @param {string} formOrigin A form origin
+   * @return {string[]} filteredRealms An array of domains related to the `formOrigin`
+   * @async
+   * @memberof LoginRelatedRealmsParent
+   */
+  async findRelatedRealms(formOrigin) {
+    try {
+      let formOriginURI = Services.io.newURI(formOrigin);
+      let originDomain = formOriginURI.host;
+      let [{ relatedRealms } = {}] =
+        await this.getSharedCredentialsCollection();
+      if (!relatedRealms) {
+        return [];
+      }
+      let filterOriginIndex;
+      let shouldInclude = false;
+      let filteredRealms = relatedRealms.filter(_realms => {
+        for (let relatedOrigin of _realms) {
+          // We can't have an origin that matches multiple entries in our related realms collection
+          // so we exit the loop early
+          if (shouldInclude) {
+            return false;
+          }
+          if (Services.eTLD.hasRootDomain(originDomain, relatedOrigin)) {
+            shouldInclude = true;
+            break;
+          }
+        }
+        return shouldInclude;
+      });
+      // * Filtered realms is a nested array due to its structure in Remote Settings
+      filteredRealms = filteredRealms.flat();
+
+      filterOriginIndex = filteredRealms.indexOf(originDomain);
+      // Removing the current formOrigin match if it exists in the related realms
+      // so that we don't return duplicates when we search for logins
+      if (filterOriginIndex !== -1) {
+        filteredRealms.splice(filterOriginIndex, 1);
+      }
+      return filteredRealms;
+    } catch (e) {
+      lazy.log.error(e);
+      return [];
+    }
+  }
+}
diff --git a/toolkit/components/passwordmgr/LoginStore.sys.mjs b/toolkit/components/passwordmgr/LoginStore.sys.mjs
new file mode 100644
index 0000000000..ad7a7e3d30
--- /dev/null
+++ b/toolkit/components/passwordmgr/LoginStore.sys.mjs
@@ -0,0 +1,181 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Handles serialization of the data and persistence into a file.
+ *
+ * The file is stored in JSON format, without indentation, using UTF-8 encoding.
+ * With indentation applied, the file would look like this:
+ *
+ * {
+ *   "logins": [
+ *     {
+ *       "id": 2,
+ *       "hostname": "http://www.example.com",
+ *       "httpRealm": null,
+ *       "formSubmitURL": "http://www.example.com",
+ *       "usernameField": "username_field",
+ *       "passwordField": "password_field",
+ *       "encryptedUsername": "...",
+ *       "encryptedPassword": "...",
+ *       "guid": "...",
+ *       "encType": 1,
+ *       "timeCreated": 1262304000000,
+ *       "timeLastUsed": 1262304000000,
+ *       "timePasswordChanged": 1262476800000,
+ *       "timesUsed": 1
+ *        // only present if other clients had fields we didn't know about
+ *       "encryptedUnknownFields: "...",
+ *     },
+ *     {
+ *       "id": 4,
+ *       (...)
+ *     }
+ *   ],
+ *   "nextId": 10,
+ *   "version": 1
+ * }
+ */
+
+// Globals
+
+import { JSONFile } from "resource://gre/modules/JSONFile.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  FXA_PWDMGR_HOST: "resource://gre/modules/FxAccountsCommon.sys.mjs",
+  FXA_PWDMGR_REALM: "resource://gre/modules/FxAccountsCommon.sys.mjs",
+});
+
+/**
+ * Current data version assigned by the code that last touched the data.
+ *
+ * This number should be updated only when it is important to understand whether
+ * an old version of the code has touched the data, for example to execute an
+ * update logic.  In most cases, this number should not be changed, in
+ * particular when no special one-time update logic is needed.
+ *
+ * For example, this number should NOT be changed when a new optional field is
+ * added to a login entry.
+ */
+const kDataVersion = 3;
+
+const MAX_DATE_MS = 8640000000000000;
+
+// LoginStore
+
+/**
+ * Inherits from JSONFile and handles serialization of login-related data and
+ * persistence into a file.
+ *
+ * @param aPath
+ *        String containing the file path where data should be saved.
+ */
+export function LoginStore(aPath, aBackupPath = "") {
+  JSONFile.call(this, {
+    path: aPath,
+    dataPostProcessor: this._dataPostProcessor.bind(this),
+    backupTo: aBackupPath,
+  });
+}
+
+LoginStore.prototype = Object.create(JSONFile.prototype);
+LoginStore.prototype.constructor = LoginStore;
+
+LoginStore.prototype._save = async function () {
+  await JSONFile.prototype._save.call(this);
+  // Notify tests that writes to the login store is complete.
+  Services.obs.notifyObservers(null, "password-storage-updated");
+
+  if (this._options.backupTo) {
+    await this._backupHandler();
+  }
+};
+
+/**
+ * Delete logins backup file if the last saved login was removed using
+ * removeLogin() or if all logins were removed at once using removeAllUserFacingLogins().
+ * Note that if the user has a fxa key stored as a login, we just update the
+ * backup to only store the key when the last saved user facing login is removed.
+ */
+LoginStore.prototype._backupHandler = async function () {
+  const logins = this._data.logins;
+  // Return early if more than one login is stored because the backup won't need
+  // updating in this case.
+  if (logins.length > 1) {
+    return;
+  }
+
+  // If one login is stored and it's a fxa sync key, we update the backup to store the
+  // key only.
+  if (
+    logins.length &&
+    logins[0].hostname == lazy.FXA_PWDMGR_HOST &&
+    logins[0].httpRealm == lazy.FXA_PWDMGR_REALM
+  ) {
+    try {
+      await IOUtils.copy(this.path, this._options.backupTo);
+
+      // This notification is specifically sent out for a test.
+      Services.obs.notifyObservers(null, "logins-backup-updated");
+    } catch (ex) {
+      console.error(ex);
+    }
+  } else if (!logins.length) {
+    // If no logins are stored anymore, delete backup.
+    await IOUtils.remove(this._options.backupTo, {
+      ignoreAbsent: true,
+    });
+  }
+};
+
+/**
+ * Synchronously work on the data just loaded into memory.
+ */
+LoginStore.prototype._dataPostProcessor = function (data) {
+  if (data.nextId === undefined) {
+    data.nextId = 1;
+  }
+
+  // Create any arrays that are not present in the saved file.
+  if (!data.logins) {
+    data.logins = [];
+  }
+
+  if (!data.potentiallyVulnerablePasswords) {
+    data.potentiallyVulnerablePasswords = [];
+  }
+
+  if (!data.dismissedBreachAlertsByLoginGUID) {
+    data.dismissedBreachAlertsByLoginGUID = {};
+  }
+
+  // sanitize dates in logins
+  if (!("version" in data) || data.version < 3) {
+    let dateProperties = ["timeCreated", "timeLastUsed", "timePasswordChanged"];
+    let now = Date.now();
+    function getEarliestDate(login, defaultDate) {
+      let earliestDate = dateProperties.reduce((earliest, pname) => {
+        let ts = login[pname];
+        return !ts ? earliest : Math.min(ts, earliest);
+      }, defaultDate);
+      return earliestDate;
+    }
+    for (let login of data.logins) {
+      for (let pname of dateProperties) {
+        let earliestDate;
+        if (!login[pname] || login[pname] > MAX_DATE_MS) {
+          login[pname] =
+            earliestDate || (earliestDate = getEarliestDate(login, now));
+        }
+      }
+    }
+  }
+
+  // Indicate that the current version of the code has touched the file.
+  data.version = kDataVersion;
+
+  return data;
+};
diff --git a/toolkit/components/passwordmgr/NewPasswordModel.sys.mjs b/toolkit/components/passwordmgr/NewPasswordModel.sys.mjs
new file mode 100644
index 0000000000..142b2e1662
--- /dev/null
+++ b/toolkit/components/passwordmgr/NewPasswordModel.sys.mjs
@@ -0,0 +1,681 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Machine learning model for identifying new password input elements
+ * using Fathom.
+ */
+
+import {
+  dom,
+  element,
+  out,
+  rule,
+  ruleset,
+  score,
+  type,
+  utils,
+  clusters,
+} from "resource://gre/modules/third_party/fathom/fathom.mjs";
+
+let { identity, isVisible, min, setDefault } = utils;
+let { euclidean } = clusters;
+
+/**
+ * ----- Start of model -----
+ *
+ * Everything below this comment up to the "End of model" comment is copied from:
+ * https://github.com/mozilla-services/fathom-login-forms/blob/78d4bf8f301b5aa6d62c06b45e826a0dd9df1afa/new-password/rulesets.js#L14-L613
+ * Deviations from that file:
+ *   - Remove import statements, instead using ``ChromeUtils.defineModuleGetter`` and destructuring assignments above.
+ *   - Set ``DEVELOPMENT`` constant to ``false``.
+ */
+
+// Whether this is running in the Vectorizer, rather than in-application, in a
+// privileged Chrome context
+const DEVELOPMENT = false;
+
+// Run me with confidence cutoff = 0.75.
+const coefficients = {
+  new: [
+    ["hasNewLabel", 2.9195094108581543],
+    ["hasConfirmLabel", 2.1672143936157227],
+    ["hasCurrentLabel", -2.1813206672668457],
+    ["closestLabelMatchesNew", 2.965045213699341],
+    ["closestLabelMatchesConfirm", 2.698647975921631],
+    ["closestLabelMatchesCurrent", -2.147423505783081],
+    ["hasNewAriaLabel", 2.8312134742736816],
+    ["hasConfirmAriaLabel", 1.5153108835220337],
+    ["hasCurrentAriaLabel", -4.368860244750977],
+    ["hasNewPlaceholder", 1.4374250173568726],
+    ["hasConfirmPlaceholder", 1.717592477798462],
+    ["hasCurrentPlaceholder", -1.9401700496673584],
+    ["forgotPasswordInFormLinkTextContent", -0.6736700534820557],
+    ["forgotPasswordInFormLinkHref", -1.3025357723236084],
+    ["forgotPasswordInFormLinkTitle", -2.9019577503204346],
+    ["forgotInFormLinkTextContent", -1.2455425262451172],
+    ["forgotInFormLinkHref", 0.4884686768054962],
+    ["forgotPasswordInFormButtonTextContent", -0.8015769720077515],
+    ["forgotPasswordOnPageLinkTextContent", 0.04422328248620033],
+    ["forgotPasswordOnPageLinkHref", -1.0331494808197021],
+    ["forgotPasswordOnPageLinkTitle", -0.08798415213823318],
+    ["forgotPasswordOnPageButtonTextContent", -1.5396910905838013],
+    ["elementAttrsMatchNew", 2.8492355346679688],
+    ["elementAttrsMatchConfirm", 1.9043376445770264],
+    ["elementAttrsMatchCurrent", -2.056903839111328],
+    ["elementAttrsMatchPassword1", 1.5833512544631958],
+    ["elementAttrsMatchPassword2", 1.3928000926971436],
+    ["elementAttrsMatchLogin", 1.738782525062561],
+    ["formAttrsMatchRegister", 2.1345033645629883],
+    ["formHasRegisterAction", 1.9337323904037476],
+    ["formButtonIsRegister", 3.0930404663085938],
+    ["formAttrsMatchLogin", -0.5816961526870728],
+    ["formHasLoginAction", -0.18886367976665497],
+    ["formButtonIsLogin", -2.332860231399536],
+    ["hasAutocompleteCurrentPassword", -0.029974736273288727],
+    ["formHasRememberMeCheckbox", 0.8600837588310242],
+    ["formHasRememberMeLabel", 0.06663893908262253],
+    ["formHasNewsletterCheckbox", -1.4851698875427246],
+    ["formHasNewsletterLabel", 2.416919231414795],
+    ["closestHeaderAboveIsLoginy", -2.0047383308410645],
+    ["closestHeaderAboveIsRegistery", 2.19451642036438],
+    ["nextInputIsConfirmy", 2.5344431400299072],
+    ["formHasMultipleVisibleInput", 2.81270694732666],
+    ["firstFieldInFormWithThreePasswordFields", -2.8964080810546875],
+  ],
+};
+
+const biases = [["new", -1.3525885343551636]];
+
+const passwordStringRegex =
+  /password|passwort|رمز عبور|mot de passe|パスワード|비밀번호|암호|wachtwoord|senha|Пароль|parol|密码|contraseña|heslo|كلمة السر|kodeord|Κωδικός|pass code|Kata sandi|hasło|รหัสผ่าน|Şifre/i;
+const passwordAttrRegex = /pw|pwd|passwd|pass/i;
+const newStringRegex =
+  /new|erstellen|create|choose|設定|신규|Créer|Nouveau|baru|nouă|nieuw/i;
+const newAttrRegex = /new/i;
+const confirmStringRegex =
+  /wiederholen|wiederholung|confirm|repeat|confirmation|verify|retype|repite|確認|の確認|تکرار|re-enter|확인|bevestigen|confirme|Повторите|tassyklamak|再次输入|ještě jednou|gentag|re-type|confirmar|Répéter|conferma|Repetaţi|again|reenter|再入力|재입력|Ulangi|Bekræft/i;
+const confirmAttrRegex = /confirm|retype/i;
+const currentAttrAndStringRegex =
+  /current|old|aktuelles|derzeitiges|当前|Atual|actuel|curentă|sekarang/i;
+const forgotStringRegex =
+  /vergessen|vergeten|forgot|oublié|dimenticata|Esqueceu|esqueci|Забыли|忘记|找回|Zapomenuté|lost|忘れた|忘れられた|忘れの方|재설정|찾기|help|فراموشی| را فراموش کرده اید|Восстановить|Unuttu|perdus|重新設定|reset|recover|change|remind|find|request|restore|trouble/i;
+const forgotHrefRegex =
+  /forgot|reset|recover|change|lost|remind|find|request|restore/i;
+const password1Regex =
+  /pw1|pwd1|pass1|passwd1|password1|pwone|pwdone|passone|passwdone|passwordone|pwfirst|pwdfirst|passfirst|passwdfirst|passwordfirst/i;
+const password2Regex =
+  /pw2|pwd2|pass2|passwd2|password2|pwtwo|pwdtwo|passtwo|passwdtwo|passwordtwo|pwsecond|pwdsecond|passsecond|passwdsecond|passwordsecond/i;
+const loginRegex =
+  /login|log in|log on|log-on|Войти|sign in|sigin|sign\/in|sign-in|sign on|sign-on|ورود|登录|Přihlásit se|Přihlaste|Авторизоваться|Авторизация|entrar|ログイン|로그인|inloggen|Συνδέσου|accedi|ログオン|Giriş Yap|登入|connecter|connectez-vous|Connexion|Вход/i;
+const loginFormAttrRegex =
+  /login|log in|log on|log-on|sign in|sigin|sign\/in|sign-in|sign on|sign-on/i;
+const registerStringRegex =
+  /create[a-zA-Z\s]+account|activate[a-zA-Z\s]+account|Zugang anlegen|Angaben prüfen|Konto erstellen|register|sign up|ثبت نام|登録|注册|cadastr|Зарегистрироваться|Регистрация|Bellige alynmak|تسجيل|ΕΓΓΡΑΦΗΣ|Εγγραφή|Créer mon compte|Créer un compte|Mendaftar|가입하기|inschrijving|Zarejestruj się|Deschideți un cont|Создать аккаунт|ร่วม|Üye Ol|registr|new account|ساخت حساب کاربری|Schrijf je|S'inscrire/i;
+const registerActionRegex =
+  /register|signup|sign-up|create-account|account\/create|join|new_account|user\/create|sign\/up|membership\/create/i;
+const registerFormAttrRegex =
+  /signup|join|register|regform|registration|new_user|AccountCreate|create_customer|CreateAccount|CreateAcct|create-account|reg-form|newuser|new-reg|new-form|new_membership/i;
+const rememberMeAttrRegex =
+  /remember|auto_login|auto-login|save_mail|save-mail|ricordami|manter|mantenha|savelogin|auto login/i;
+const rememberMeStringRegex =
+  /remember me|keep me logged in|keep me signed in|save email address|save id|stay signed in|ricordami|次回からログオンIDの入力を省略する|メールアドレスを保存する|を保存|아이디저장|아이디 저장|로그인 상태 유지|lembrar|manter conectado|mantenha-me conectado|Запомни меня|запомнить меня|Запомните меня|Не спрашивать в следующий раз|下次自动登录|记住我/i;
+const newsletterStringRegex = /newsletter|ニュースレター/i;
+const passwordStringAndAttrRegex = new RegExp(
+  passwordStringRegex.source + "|" + passwordAttrRegex.source,
+  "i"
+);
+
+function makeRuleset(coeffs, biases) {
+  // HTMLElement => (selector => Array<HTMLElement>) nested map to cache querySelectorAll calls.
+  let elementToSelectors;
+  // We want to clear the cache each time the model is executed to get the latest DOM snapshot
+  // for each classification.
+  function clearCache() {
+    // WeakMaps do not have a clear method
+    elementToSelectors = new WeakMap();
+  }
+
+  function hasLabelMatchingRegex(element, regex) {
+    // Check element.labels
+    const labels = element.labels;
+    // TODO: Should I be concerned with multiple labels?
+    if (labels !== null && labels.length) {
+      return regex.test(labels[0].textContent);
+    }
+
+    // Check element.aria-labelledby
+    let labelledBy = element.getAttribute("aria-labelledby");
+    if (labelledBy !== null) {
+      labelledBy = labelledBy
+        .split(" ")
+        .map(id => element.getRootNode().getElementById(id))
+        .filter(el => el);
+      if (labelledBy.length === 1) {
+        return regex.test(labelledBy[0].textContent);
+      } else if (labelledBy.length > 1) {
+        return regex.test(
+          min(labelledBy, node => euclidean(node, element)).textContent
+        );
+      }
+    }
+
+    const parentElement = element.parentElement;
+    // Bug 1634819: element.parentElement is null if element.parentNode is a ShadowRoot
+    if (!parentElement) {
+      return false;
+    }
+    // Check if the input is in a <td>, and, if so, check the textContent of the containing <tr>
+    if (parentElement.tagName === "TD" && parentElement.parentElement) {
+      // TODO: How bad is the assumption that the <tr> won't be the parent of the <td>?
+      return regex.test(parentElement.parentElement.textContent);
+    }
+
+    // Check if the input is in a <dd>, and, if so, check the textContent of the preceding <dt>
+    if (
+      parentElement.tagName === "DD" &&
+      // previousElementSibling can be null
+      parentElement.previousElementSibling
+    ) {
+      return regex.test(parentElement.previousElementSibling.textContent);
+    }
+    return false;
+  }
+
+  function closestLabelMatchesRegex(element, regex) {
+    const previousElementSibling = element.previousElementSibling;
+    if (
+      previousElementSibling !== null &&
+      previousElementSibling.tagName === "LABEL"
+    ) {
+      return regex.test(previousElementSibling.textContent);
+    }
+
+    const nextElementSibling = element.nextElementSibling;
+    if (nextElementSibling !== null && nextElementSibling.tagName === "LABEL") {
+      return regex.test(nextElementSibling.textContent);
+    }
+
+    const closestLabelWithinForm = closestSelectorElementWithinElement(
+      element,
+      element.form,
+      "label"
+    );
+    return containsRegex(
+      regex,
+      closestLabelWithinForm,
+      closestLabelWithinForm => closestLabelWithinForm.textContent
+    );
+  }
+
+  function containsRegex(regex, thingOrNull, thingToString = identity) {
+    return thingOrNull !== null && regex.test(thingToString(thingOrNull));
+  }
+
+  function closestSelectorElementWithinElement(
+    toElement,
+    withinElement,
+    querySelector
+  ) {
+    if (withinElement !== null) {
+      let nodeList = Array.from(withinElement.querySelectorAll(querySelector));
+      if (nodeList.length) {
+        return min(nodeList, node => euclidean(node, toElement));
+      }
+    }
+    return null;
+  }
+
+  function hasAriaLabelMatchingRegex(element, regex) {
+    return containsRegex(regex, element.getAttribute("aria-label"));
+  }
+
+  function hasPlaceholderMatchingRegex(element, regex) {
+    return containsRegex(regex, element.getAttribute("placeholder"));
+  }
+
+  function testRegexesAgainstAnchorPropertyWithinElement(
+    property,
+    element,
+    ...regexes
+  ) {
+    return hasSomeMatchingPredicateForSelectorWithinElement(
+      element,
+      "a",
+      anchor => {
+        const propertyValue = anchor[property];
+        return regexes.every(regex => regex.test(propertyValue));
+      }
+    );
+  }
+
+  function testFormButtonsAgainst(element, stringRegex) {
+    const form = element.form;
+    if (form !== null) {
+      let inputs = Array.from(
+        form.querySelectorAll("input[type=submit],input[type=button]")
+      );
+      inputs = inputs.filter(input => {
+        return stringRegex.test(input.value);
+      });
+      if (inputs.length) {
+        return true;
+      }
+
+      return hasSomeMatchingPredicateForSelectorWithinElement(
+        form,
+        "button",
+        button => {
+          return (
+            stringRegex.test(button.value) ||
+            stringRegex.test(button.textContent) ||
+            stringRegex.test(button.id) ||
+            stringRegex.test(button.title)
+          );
+        }
+      );
+    }
+    return false;
+  }
+
+  function hasAutocompleteCurrentPassword(fnode) {
+    return fnode.element.autocomplete === "current-password";
+  }
+
+  // Check cache before calling querySelectorAll on element
+  function getElementDescendants(element, selector) {
+    // Use the element to look up the selector map:
+    const selectorToDescendants = setDefault(
+      elementToSelectors,
+      element,
+      () => new Map()
+    );
+
+    // Use the selector to grab the descendants:
+    return setDefault(selectorToDescendants, selector, () =>
+      Array.from(element.querySelectorAll(selector))
+    );
+  }
+
+  /**
+   * Return whether the form element directly after this one looks like a
+   * confirm-password input.
+   */
+  function nextInputIsConfirmy(fnode) {
+    const form = fnode.element.form;
+    const me = fnode.element;
+    if (form !== null) {
+      let afterMe = false;
+      for (const formEl of form.elements) {
+        if (formEl === me) {
+          afterMe = true;
+        } else if (afterMe) {
+          if (
+            formEl.type === "password" &&
+            !formEl.disabled &&
+            formEl.getAttribute("aria-hidden") !== "true"
+          ) {
+            // Now we're looking at a passwordy, visible input[type=password]
+            // directly after me.
+            return elementAttrsMatchRegex(formEl, confirmAttrRegex);
+            // We could check other confirmy smells as well. Balance accuracy
+            // against time and complexity.
+          }
+          // We look only at the very next element, so we may be thrown off by
+          // Hide buttons and such.
+          break;
+        }
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Returns true when the number of visible input found in the form is over
+   * the given threshold.
+   *
+   * Since the idea in the signal is based on the fact that registration pages
+   * often have multiple inputs, this rule only selects inputs whose type is
+   * either email, password, text, tel or empty, which are more likely a input
+   * field for users to fill their information.
+   */
+  function formHasMultipleVisibleInput(element, selector, threshold) {
+    let form = element.form;
+    if (!form) {
+      // For password fields that don't have an associated form, we apply a heuristic
+      // to find a "form" for it. The heuristic works as follow:
+      // 1. Locate the closest preceding input.
+      // 2. Find the lowest common ancestor of the password field and the closet
+      //    preceding input.
+      // 3. Assume the common ancestor is the "form" of the password input.
+      const previous = closestElementAbove(element, selector);
+      if (!previous) {
+        return false;
+      }
+      form = findLowestCommonAncestor(previous, element);
+      if (!form) {
+        return false;
+      }
+    }
+    const inputs = Array.from(form.querySelectorAll(selector));
+    for (const input of inputs) {
+      // don't need to check visibility for the element we're testing against
+      if (element === input || isVisible(input)) {
+        threshold--;
+        if (threshold === 0) {
+          return true;
+        }
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Returns true when there are three password fields in the form and the passed
+   * element is the first one.
+   *
+   * The signal is based on that change-password forms with 3 password fields often
+   * have the "current password", "new password", and "confirm password" pattern.
+   */
+  function firstFieldInFormWithThreePasswordFields(fnode) {
+    const element = fnode.element;
+    const form = element.form;
+    if (form) {
+      let elements = form.querySelectorAll(
+        "input[type=password]:not([disabled], [aria-hidden=true])"
+      );
+      // Only care forms with three password fields. If there are more than three password
+      // fields found, probably we include some hidden fields, so just ignore it.
+      if (elements.length == 3 && elements[0] == element) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  function hasSomeMatchingPredicateForSelectorWithinElement(
+    element,
+    selector,
+    matchingPredicate
+  ) {
+    if (element === null) {
+      return false;
+    }
+    const elements = getElementDescendants(element, selector);
+    return elements.some(matchingPredicate);
+  }
+
+  function textContentMatchesRegexes(element, ...regexes) {
+    const textContent = element.textContent;
+    return regexes.every(regex => regex.test(textContent));
+  }
+
+  function closestHeaderAboveMatchesRegex(element, regex) {
+    const closestHeader = closestElementAbove(
+      element,
+      "h1,h2,h3,h4,h5,h6,div[class*=heading],div[class*=header],div[class*=title],legend"
+    );
+    if (closestHeader !== null) {
+      return regex.test(closestHeader.textContent);
+    }
+    return false;
+  }
+
+  function closestElementAbove(element, selector) {
+    let elements = Array.from(element.ownerDocument.querySelectorAll(selector));
+    for (let i = elements.length - 1; i >= 0; --i) {
+      if (
+        element.compareDocumentPosition(elements[i]) &
+        Node.DOCUMENT_POSITION_PRECEDING
+      ) {
+        return elements[i];
+      }
+    }
+    return null;
+  }
+
+  function findLowestCommonAncestor(elementA, elementB) {
+    // Walk up the ancestor chain of both elements and compare whether the
+    // ancestors in the depth are the same. If they are not the same, the
+    // ancestor in the previous run is the lowest common ancestor.
+    function getAncestorChain(element) {
+      let ancestors = [];
+      let p = element.parentNode;
+      while (p) {
+        ancestors.push(p);
+        p = p.parentNode;
+      }
+      return ancestors;
+    }
+
+    let aAncestors = getAncestorChain(elementA);
+    let bAncestors = getAncestorChain(elementB);
+    let posA = aAncestors.length - 1;
+    let posB = bAncestors.length - 1;
+    for (; posA >= 0 && posB >= 0; posA--, posB--) {
+      if (aAncestors[posA] != bAncestors[posB]) {
+        return aAncestors[posA + 1];
+      }
+    }
+    return null;
+  }
+
+  function elementAttrsMatchRegex(element, regex) {
+    if (element !== null) {
+      return (
+        regex.test(element.id) ||
+        regex.test(element.name) ||
+        regex.test(element.className)
+      );
+    }
+    return false;
+  }
+
+  /**
+   * Let us compactly represent a collection of rules that all take a single
+   * type with no .when() clause and have only a score() call on the right-hand
+   * side.
+   */
+  function* simpleScoringRulesTakingType(inType, ruleMap) {
+    for (const [name, scoringCallback] of Object.entries(ruleMap)) {
+      yield rule(type(inType), score(scoringCallback), { name });
+    }
+  }
+
+  return ruleset(
+    [
+      rule(
+        DEVELOPMENT
+          ? dom(
+              "input[type=password]:not([disabled], [aria-hidden=true])"
+            ).when(isVisible)
+          : element("input"),
+        type("new").note(clearCache)
+      ),
+      ...simpleScoringRulesTakingType("new", {
+        hasNewLabel: fnode =>
+          hasLabelMatchingRegex(fnode.element, newStringRegex),
+        hasConfirmLabel: fnode =>
+          hasLabelMatchingRegex(fnode.element, confirmStringRegex),
+        hasCurrentLabel: fnode =>
+          hasLabelMatchingRegex(fnode.element, currentAttrAndStringRegex),
+        closestLabelMatchesNew: fnode =>
+          closestLabelMatchesRegex(fnode.element, newStringRegex),
+        closestLabelMatchesConfirm: fnode =>
+          closestLabelMatchesRegex(fnode.element, confirmStringRegex),
+        closestLabelMatchesCurrent: fnode =>
+          closestLabelMatchesRegex(fnode.element, currentAttrAndStringRegex),
+        hasNewAriaLabel: fnode =>
+          hasAriaLabelMatchingRegex(fnode.element, newStringRegex),
+        hasConfirmAriaLabel: fnode =>
+          hasAriaLabelMatchingRegex(fnode.element, confirmStringRegex),
+        hasCurrentAriaLabel: fnode =>
+          hasAriaLabelMatchingRegex(fnode.element, currentAttrAndStringRegex),
+        hasNewPlaceholder: fnode =>
+          hasPlaceholderMatchingRegex(fnode.element, newStringRegex),
+        hasConfirmPlaceholder: fnode =>
+          hasPlaceholderMatchingRegex(fnode.element, confirmStringRegex),
+        hasCurrentPlaceholder: fnode =>
+          hasPlaceholderMatchingRegex(fnode.element, currentAttrAndStringRegex),
+        forgotPasswordInFormLinkTextContent: fnode =>
+          testRegexesAgainstAnchorPropertyWithinElement(
+            "textContent",
+            fnode.element.form,
+            passwordStringRegex,
+            forgotStringRegex
+          ),
+        forgotPasswordInFormLinkHref: fnode =>
+          testRegexesAgainstAnchorPropertyWithinElement(
+            "href",
+            fnode.element.form,
+            passwordStringAndAttrRegex,
+            forgotHrefRegex
+          ),
+        forgotPasswordInFormLinkTitle: fnode =>
+          testRegexesAgainstAnchorPropertyWithinElement(
+            "title",
+            fnode.element.form,
+            passwordStringRegex,
+            forgotStringRegex
+          ),
+        forgotInFormLinkTextContent: fnode =>
+          testRegexesAgainstAnchorPropertyWithinElement(
+            "textContent",
+            fnode.element.form,
+            forgotStringRegex
+          ),
+        forgotInFormLinkHref: fnode =>
+          testRegexesAgainstAnchorPropertyWithinElement(
+            "href",
+            fnode.element.form,
+            forgotHrefRegex
+          ),
+        forgotPasswordInFormButtonTextContent: fnode =>
+          hasSomeMatchingPredicateForSelectorWithinElement(
+            fnode.element.form,
+            "button",
+            button =>
+              textContentMatchesRegexes(
+                button,
+                passwordStringRegex,
+                forgotStringRegex
+              )
+          ),
+        forgotPasswordOnPageLinkTextContent: fnode =>
+          testRegexesAgainstAnchorPropertyWithinElement(
+            "textContent",
+            fnode.element.ownerDocument,
+            passwordStringRegex,
+            forgotStringRegex
+          ),
+        forgotPasswordOnPageLinkHref: fnode =>
+          testRegexesAgainstAnchorPropertyWithinElement(
+            "href",
+            fnode.element.ownerDocument,
+            passwordStringAndAttrRegex,
+            forgotHrefRegex
+          ),
+        forgotPasswordOnPageLinkTitle: fnode =>
+          testRegexesAgainstAnchorPropertyWithinElement(
+            "title",
+            fnode.element.ownerDocument,
+            passwordStringRegex,
+            forgotStringRegex
+          ),
+        forgotPasswordOnPageButtonTextContent: fnode =>
+          hasSomeMatchingPredicateForSelectorWithinElement(
+            fnode.element.ownerDocument,
+            "button",
+            button =>
+              textContentMatchesRegexes(
+                button,
+                passwordStringRegex,
+                forgotStringRegex
+              )
+          ),
+        elementAttrsMatchNew: fnode =>
+          elementAttrsMatchRegex(fnode.element, newAttrRegex),
+        elementAttrsMatchConfirm: fnode =>
+          elementAttrsMatchRegex(fnode.element, confirmAttrRegex),
+        elementAttrsMatchCurrent: fnode =>
+          elementAttrsMatchRegex(fnode.element, currentAttrAndStringRegex),
+        elementAttrsMatchPassword1: fnode =>
+          elementAttrsMatchRegex(fnode.element, password1Regex),
+        elementAttrsMatchPassword2: fnode =>
+          elementAttrsMatchRegex(fnode.element, password2Regex),
+        elementAttrsMatchLogin: fnode =>
+          elementAttrsMatchRegex(fnode.element, loginRegex),
+        formAttrsMatchRegister: fnode =>
+          elementAttrsMatchRegex(fnode.element.form, registerFormAttrRegex),
+        formHasRegisterAction: fnode =>
+          containsRegex(
+            registerActionRegex,
+            fnode.element.form,
+            form => form.action
+          ),
+        formButtonIsRegister: fnode =>
+          testFormButtonsAgainst(fnode.element, registerStringRegex),
+        formAttrsMatchLogin: fnode =>
+          elementAttrsMatchRegex(fnode.element.form, loginFormAttrRegex),
+        formHasLoginAction: fnode =>
+          containsRegex(loginRegex, fnode.element.form, form => form.action),
+        formButtonIsLogin: fnode =>
+          testFormButtonsAgainst(fnode.element, loginRegex),
+        hasAutocompleteCurrentPassword,
+        formHasRememberMeCheckbox: fnode =>
+          hasSomeMatchingPredicateForSelectorWithinElement(
+            fnode.element.form,
+            "input[type=checkbox]",
+            checkbox =>
+              rememberMeAttrRegex.test(checkbox.id) ||
+              rememberMeAttrRegex.test(checkbox.name)
+          ),
+        formHasRememberMeLabel: fnode =>
+          hasSomeMatchingPredicateForSelectorWithinElement(
+            fnode.element.form,
+            "label",
+            label => rememberMeStringRegex.test(label.textContent)
+          ),
+        formHasNewsletterCheckbox: fnode =>
+          hasSomeMatchingPredicateForSelectorWithinElement(
+            fnode.element.form,
+            "input[type=checkbox]",
+            checkbox =>
+              checkbox.id.includes("newsletter") ||
+              checkbox.name.includes("newsletter")
+          ),
+        formHasNewsletterLabel: fnode =>
+          hasSomeMatchingPredicateForSelectorWithinElement(
+            fnode.element.form,
+            "label",
+            label => newsletterStringRegex.test(label.textContent)
+          ),
+        closestHeaderAboveIsLoginy: fnode =>
+          closestHeaderAboveMatchesRegex(fnode.element, loginRegex),
+        closestHeaderAboveIsRegistery: fnode =>
+          closestHeaderAboveMatchesRegex(fnode.element, registerStringRegex),
+        nextInputIsConfirmy,
+        formHasMultipleVisibleInput: fnode =>
+          formHasMultipleVisibleInput(
+            fnode.element,
+            "input[type=email],input[type=password],input[type=text],input[type=tel]",
+            3
+          ),
+        firstFieldInFormWithThreePasswordFields,
+      }),
+      rule(type("new"), out("new")),
+    ],
+    coeffs,
+    biases
+  );
+}
+
+/*
+ * ----- End of model -----
+ */
+
+export const NewPasswordModel = {
+  type: "new",
+  rules: makeRuleset([...coefficients.new], biases),
+};
diff --git a/toolkit/components/passwordmgr/OSCrypto_win.sys.mjs b/toolkit/components/passwordmgr/OSCrypto_win.sys.mjs
new file mode 100644
index 0000000000..5b3f1d7929
--- /dev/null
+++ b/toolkit/components/passwordmgr/OSCrypto_win.sys.mjs
@@ -0,0 +1,284 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import { ctypes } from "resource://gre/modules/ctypes.sys.mjs";
+
+const FLAGS_NOT_SET = 0;
+
+const wintypes = {
+  BOOL: ctypes.bool,
+  BYTE: ctypes.uint8_t,
+  DWORD: ctypes.uint32_t,
+  PBYTE: ctypes.unsigned_char.ptr,
+  PCHAR: ctypes.char.ptr,
+  PDWORD: ctypes.uint32_t.ptr,
+  PVOID: ctypes.voidptr_t,
+  WORD: ctypes.uint16_t,
+};
+
+export function OSCrypto() {
+  this._structs = {};
+  this._functions = new Map();
+  this._libs = new Map();
+  this._structs.DATA_BLOB = new ctypes.StructType("DATA_BLOB", [
+    { cbData: wintypes.DWORD },
+    { pbData: wintypes.PVOID },
+  ]);
+
+  try {
+    this._libs.set("crypt32", ctypes.open("Crypt32"));
+    this._libs.set("kernel32", ctypes.open("Kernel32"));
+
+    this._functions.set(
+      "CryptProtectData",
+      this._libs
+        .get("crypt32")
+        .declare(
+          "CryptProtectData",
+          ctypes.winapi_abi,
+          wintypes.DWORD,
+          this._structs.DATA_BLOB.ptr,
+          wintypes.PVOID,
+          wintypes.PVOID,
+          wintypes.PVOID,
+          wintypes.PVOID,
+          wintypes.DWORD,
+          this._structs.DATA_BLOB.ptr
+        )
+    );
+    this._functions.set(
+      "CryptUnprotectData",
+      this._libs
+        .get("crypt32")
+        .declare(
+          "CryptUnprotectData",
+          ctypes.winapi_abi,
+          wintypes.DWORD,
+          this._structs.DATA_BLOB.ptr,
+          wintypes.PVOID,
+          wintypes.PVOID,
+          wintypes.PVOID,
+          wintypes.PVOID,
+          wintypes.DWORD,
+          this._structs.DATA_BLOB.ptr
+        )
+    );
+    this._functions.set(
+      "LocalFree",
+      this._libs
+        .get("kernel32")
+        .declare("LocalFree", ctypes.winapi_abi, wintypes.DWORD, wintypes.PVOID)
+    );
+  } catch (ex) {
+    console.error(ex);
+    this.finalize();
+    throw ex;
+  }
+}
+
+OSCrypto.prototype = {
+  /**
+   * Convert an array containing only two bytes unsigned numbers to a string.
+   * @param {number[]} arr - the array that needs to be converted.
+   * @returns {string} the string representation of the array.
+   */
+  arrayToString(arr) {
+    let str = "";
+    for (let i = 0; i < arr.length; i++) {
+      str += String.fromCharCode(arr[i]);
+    }
+    return str;
+  },
+
+  /**
+   * Convert a string to an array.
+   * @param {string} str - the string that needs to be converted.
+   * @returns {number[]} the array representation of the string.
+   */
+  stringToArray(str) {
+    let arr = [];
+    for (let i = 0; i < str.length; i++) {
+      arr.push(str.charCodeAt(i));
+    }
+    return arr;
+  },
+
+  /**
+   * Calculate the hash value used by IE as the name of the registry value where login details are
+   * stored.
+   * @param {string} data - the string value that needs to be hashed.
+   * @returns {string} the hash value of the string.
+   */
+  getIELoginHash(data) {
+    // return the two-digit hexadecimal code for a byte
+    function toHexString(charCode) {
+      return ("00" + charCode.toString(16)).slice(-2);
+    }
+
+    // the data needs to be encoded in null terminated UTF-16
+    data += "\0";
+
+    // dataArray is an array of bytes
+    let dataArray = new Array(data.length * 2);
+    for (let i = 0; i < data.length; i++) {
+      let c = data.charCodeAt(i);
+      let lo = c & 0xff;
+      let hi = (c & 0xff00) >> 8;
+      dataArray[i * 2] = lo;
+      dataArray[i * 2 + 1] = hi;
+    }
+
+    // calculation of SHA1 hash value
+    let cryptoHash = Cc["@mozilla.org/security/hash;1"].createInstance(
+      Ci.nsICryptoHash
+    );
+    cryptoHash.init(cryptoHash.SHA1);
+    cryptoHash.update(dataArray, dataArray.length);
+    let hash = cryptoHash.finish(false);
+
+    let tail = 0; // variable to calculate value for the last 2 bytes
+    // convert to a character string in hexadecimal notation
+    for (let c of hash) {
+      tail += c.charCodeAt(0);
+    }
+    hash += String.fromCharCode(tail % 256);
+
+    // convert the binary hash data to a hex string.
+    let hashStr = Array.from(hash, (c, i) =>
+      toHexString(hash.charCodeAt(i))
+    ).join("");
+    return hashStr.toUpperCase();
+  },
+
+  _getEntropyParam(entropy) {
+    if (!entropy) {
+      return null;
+    }
+    let entropyArray = this.stringToArray(entropy);
+    entropyArray.push(0); // Null-terminate the data.
+    let entropyData = wintypes.WORD.array(entropyArray.length)(entropyArray);
+    let optionalEntropy = new this._structs.DATA_BLOB(
+      entropyData.length * wintypes.WORD.size,
+      entropyData
+    );
+    return optionalEntropy.address();
+  },
+
+  _convertWinArrayToJSArray(dataBlob) {
+    // Convert DATA_BLOB to JS accessible array
+    return ctypes.cast(
+      dataBlob.pbData,
+      wintypes.BYTE.array(dataBlob.cbData).ptr
+    ).contents;
+  },
+
+  /**
+   * Decrypt a string using the windows CryptUnprotectData API.
+   * @param {string} data - the encrypted string that needs to be decrypted.
+   * @param {?string} entropy - the entropy value of the decryption (could be null). Its value must
+   * be the same as the one used when the data was encrypted.
+   * @param {?string} output - how to return the decrypted data default string
+   * @returns {string|Uint8Array} the decryption of the string.
+   */
+  decryptData(data, entropy = null, output = "string") {
+    let array = this.stringToArray(data);
+    let encryptedData = wintypes.BYTE.array(array.length)(array);
+    let inData = new this._structs.DATA_BLOB(
+      encryptedData.length,
+      encryptedData
+    );
+    let outData = new this._structs.DATA_BLOB();
+    let entropyParam = this._getEntropyParam(entropy);
+
+    try {
+      let status = this._functions.get("CryptUnprotectData")(
+        inData.address(),
+        null,
+        entropyParam,
+        null,
+        null,
+        FLAGS_NOT_SET,
+        outData.address()
+      );
+      if (status === 0) {
+        throw new Error("decryptData failed: " + ctypes.winLastError);
+      }
+
+      let decrypted = this._convertWinArrayToJSArray(outData);
+
+      // Return raw bytes to handle non-string results
+      const bytes = new Uint8Array(decrypted);
+      if (output === "bytes") {
+        return bytes;
+      }
+
+      // Output that may include characters outside of the 0-255 (byte) range needs to use TextDecoder.
+      return new TextDecoder().decode(bytes);
+    } finally {
+      if (outData.pbData) {
+        this._functions.get("LocalFree")(outData.pbData);
+      }
+    }
+  },
+
+  /**
+   * Encrypt a string using the windows CryptProtectData API.
+   * @param {string} data - the string that is going to be encrypted.
+   * @param {?string} entropy - the entropy value of the encryption (could be null). Its value must
+   * be the same as the one that is going to be used for the decryption.
+   * @returns {string} the encrypted string.
+   */
+  encryptData(data, entropy = null) {
+    // Input that may include characters outside of the 0-255 (byte) range needs to use TextEncoder.
+    let decryptedByteData = [...new TextEncoder().encode(data)];
+    let decryptedData = wintypes.BYTE.array(decryptedByteData.length)(
+      decryptedByteData
+    );
+
+    let inData = new this._structs.DATA_BLOB(
+      decryptedData.length,
+      decryptedData
+    );
+    let outData = new this._structs.DATA_BLOB();
+    let entropyParam = this._getEntropyParam(entropy);
+
+    try {
+      let status = this._functions.get("CryptProtectData")(
+        inData.address(),
+        null,
+        entropyParam,
+        null,
+        null,
+        FLAGS_NOT_SET,
+        outData.address()
+      );
+      if (status === 0) {
+        throw new Error("encryptData failed: " + ctypes.winLastError);
+      }
+
+      let encrypted = this._convertWinArrayToJSArray(outData);
+      return this.arrayToString(encrypted);
+    } finally {
+      if (outData.pbData) {
+        this._functions.get("LocalFree")(outData.pbData);
+      }
+    }
+  },
+
+  /**
+   * Must be invoked once after last use of any of the provided helpers.
+   */
+  finalize() {
+    this._structs = {};
+    this._functions.clear();
+    for (let lib of this._libs.values()) {
+      try {
+        lib.close();
+      } catch (ex) {
+        console.error(ex);
+      }
+    }
+    this._libs.clear();
+  },
+};
diff --git a/toolkit/components/passwordmgr/PasswordGenerator.sys.mjs b/toolkit/components/passwordmgr/PasswordGenerator.sys.mjs
new file mode 100644
index 0000000000..0f2a407cea
--- /dev/null
+++ b/toolkit/components/passwordmgr/PasswordGenerator.sys.mjs
@@ -0,0 +1,229 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This file is a port of a subset of Chromium's implementation from
+ * https://cs.chromium.org/chromium/src/components/password_manager/core/browser/generation/password_generator.cc?l=93&rcl=a896a3ac4ea731b5ab3d2ab5bd76a139885d5c4f
+ * which is Copyright 2018 The Chromium Authors. All rights reserved.
+ */
+
+const DEFAULT_PASSWORD_LENGTH = 15;
+const MAX_UINT8 = Math.pow(2, 8) - 1;
+const MAX_UINT32 = Math.pow(2, 32) - 1;
+
+// Some characters are removed due to visual similarity:
+const LOWER_CASE_ALPHA = "abcdefghijkmnpqrstuvwxyz"; // no 'l' or 'o'
+const UPPER_CASE_ALPHA = "ABCDEFGHJKLMNPQRSTUVWXYZ"; // no 'I' or 'O'
+const DIGITS = "23456789"; // no '1' or '0'
+const SPECIAL_CHARACTERS = "-~!@#$%^&*_+=)}:;\"'>,.?]";
+
+const REQUIRED_CHARACTER_CLASSES = [
+  LOWER_CASE_ALPHA,
+  UPPER_CASE_ALPHA,
+  DIGITS,
+  SPECIAL_CHARACTERS,
+];
+
+// Consts for different password rules
+const REQUIRED = "required";
+const MAX_LENGTH = "maxlength";
+const MIN_LENGTH = "minlength";
+const MAX_CONSECUTIVE = "max-consecutive";
+const UPPER = "upper";
+const LOWER = "lower";
+const DIGIT = "digit";
+const SPECIAL = "special";
+
+// Default password rules
+const DEFAULT_RULES = new Map();
+DEFAULT_RULES.set(MIN_LENGTH, REQUIRED_CHARACTER_CLASSES.length);
+DEFAULT_RULES.set(MAX_LENGTH, MAX_UINT8);
+DEFAULT_RULES.set(REQUIRED, [UPPER, LOWER, DIGIT, SPECIAL]);
+
+export const PasswordGenerator = {
+  /**
+   * @param {Object} options
+   * @param {number} options.length - length of the generated password if there are no rules that override the length
+   * @param {Map} options.rules - map of password rules
+   * @returns {string} password that was generated
+   * @throws Error if `length` is invalid
+   * @copyright 2018 The Chromium Authors. All rights reserved.
+   * @see https://cs.chromium.org/chromium/src/components/password_manager/core/browser/generation/password_generator.cc?l=93&rcl=a896a3ac4ea731b5ab3d2ab5bd76a139885d5c4f
+   */
+  generatePassword({
+    length = DEFAULT_PASSWORD_LENGTH,
+    rules = DEFAULT_RULES,
+    inputMaxLength,
+  }) {
+    rules = new Map([...DEFAULT_RULES, ...rules]);
+    if (rules.get(MIN_LENGTH) > length) {
+      length = rules.get(MIN_LENGTH);
+    }
+    if (rules.get(MAX_LENGTH) < length) {
+      length = rules.get(MAX_LENGTH);
+    }
+    if (inputMaxLength > 0 && inputMaxLength < length) {
+      length = inputMaxLength;
+    }
+
+    let password = "";
+    let requiredClasses = [];
+    let allRequiredCharacters = "";
+
+    // Generate one character of each required class and/or required character list from the rules
+    this._addRequiredClassesAndCharacters(rules, requiredClasses);
+
+    // Generate one of each required class
+    for (const charClassString of requiredClasses) {
+      password +=
+        charClassString[this._randomUInt8Index(charClassString.length)];
+      if (Array.isArray(charClassString)) {
+        // Convert array into single string so that commas aren't
+        // concatenated with each character in the arbitrary character array.
+        allRequiredCharacters += charClassString.join("");
+      } else {
+        allRequiredCharacters += charClassString;
+      }
+    }
+
+    // Now fill the rest of the password with random characters.
+    while (password.length < length) {
+      password +=
+        allRequiredCharacters[
+          this._randomUInt8Index(allRequiredCharacters.length)
+        ];
+    }
+
+    // So far the password contains the minimally required characters at the
+    // the beginning. Therefore, we create a random permutation.
+    password = this._shuffleString(password);
+
+    // Make sure the password passes the "max-consecutive" rule, if the rule exists
+    if (rules.has(MAX_CONSECUTIVE)) {
+      // Ensures that a password isn't shuffled an infinite number of times.
+      const DEFAULT_NUMBER_OF_SHUFFLES = 15;
+      let shuffleCount = 0;
+      let consecutiveFlag = this._checkConsecutiveCharacters(
+        password,
+        rules.get(MAX_CONSECUTIVE)
+      );
+      while (!consecutiveFlag) {
+        password = this._shuffleString(password);
+        consecutiveFlag = this._checkConsecutiveCharacters(
+          password,
+          rules.get(MAX_CONSECUTIVE)
+        );
+        ++shuffleCount;
+        if (shuffleCount === DEFAULT_NUMBER_OF_SHUFFLES) {
+          consecutiveFlag = true;
+        }
+      }
+    }
+
+    return password;
+  },
+
+  /**
+   * Adds special characters and/or other required characters to the requiredCharacters array.
+   * @param {Map} rules
+   * @param {string[]} requiredClasses
+   */
+  _addRequiredClassesAndCharacters(rules, requiredClasses) {
+    for (const charClass of rules.get(REQUIRED)) {
+      if (charClass === UPPER) {
+        requiredClasses.push(UPPER_CASE_ALPHA);
+      } else if (charClass === LOWER) {
+        requiredClasses.push(LOWER_CASE_ALPHA);
+      } else if (charClass === DIGIT) {
+        requiredClasses.push(DIGITS);
+      } else if (charClass === SPECIAL) {
+        requiredClasses.push(SPECIAL_CHARACTERS);
+      } else {
+        requiredClasses.push(charClass);
+      }
+    }
+  },
+
+  /**
+   * @param range to generate the number in
+   * @returns a random number in range [0, range).
+   * @copyright 2018 The Chromium Authors. All rights reserved.
+   * @see https://cs.chromium.org/chromium/src/base/rand_util.cc?l=58&rcl=648a59893e4ed5303b5c381b03ce0c75e4165617
+   */
+  _randomUInt8Index(range) {
+    if (range > MAX_UINT8) {
+      throw new Error("`range` cannot fit into uint8");
+    }
+    // We must discard random results above this number, as they would
+    // make the random generator non-uniform (consider e.g. if
+    // MAX_UINT64 was 7 and |range| was 5, then a result of 1 would be twice
+    // as likely as a result of 3 or 4).
+    // See https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle#Modulo_bias
+    const MAX_ACCEPTABLE_VALUE = Math.floor(MAX_UINT8 / range) * range - 1;
+
+    const randomValueArr = new Uint8Array(1);
+    do {
+      crypto.getRandomValues(randomValueArr);
+    } while (randomValueArr[0] > MAX_ACCEPTABLE_VALUE);
+    return randomValueArr[0] % range;
+  },
+
+  /**
+   * Shuffle the order of characters in a string.
+   * @param {string} str to shuffle
+   * @returns {string} shuffled string
+   */
+  _shuffleString(str) {
+    let arr = Array.from(str);
+    // Generate all the random numbers that will be needed.
+    const randomValues = new Uint32Array(arr.length - 1);
+    crypto.getRandomValues(randomValues);
+
+    // Fisher-Yates Shuffle
+    // https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
+    for (let i = arr.length - 1; i > 0; i--) {
+      const j = Math.floor((randomValues[i - 1] / MAX_UINT32) * (i + 1));
+      [arr[i], arr[j]] = [arr[j], arr[i]];
+    }
+    return arr.join("");
+  },
+
+  /**
+   * Determine the number of consecutive characters in a string.
+   * This is primarily used to validate the "max-consecutive" rule
+   * of a generated password.
+   * @param {string} generatedPassword
+   * @param {number} value the number of consecutive characters allowed
+   * @return {boolean} `true` if the generatePassword has less than the value argument number of characters, `false` otherwise
+   */
+  _checkConsecutiveCharacters(generatedPassword, value) {
+    let max = 0;
+    for (let start = 0, end = 1; end < generatedPassword.length; ) {
+      if (generatedPassword[end] === generatedPassword[start]) {
+        if (max < end - start + 1) {
+          max = end - start + 1;
+          if (max > value) {
+            return false;
+          }
+        }
+        end++;
+      } else {
+        start = end++;
+      }
+    }
+    return true;
+  },
+  _getUpperCaseCharacters() {
+    return UPPER_CASE_ALPHA;
+  },
+  _getLowerCaseCharacters() {
+    return LOWER_CASE_ALPHA;
+  },
+  _getDigits() {
+    return DIGITS;
+  },
+  _getSpecialCharacters() {
+    return SPECIAL_CHARACTERS;
+  },
+};
diff --git a/toolkit/components/passwordmgr/PasswordRulesManager.sys.mjs b/toolkit/components/passwordmgr/PasswordRulesManager.sys.mjs
new file mode 100644
index 0000000000..32757e51c1
--- /dev/null
+++ b/toolkit/components/passwordmgr/PasswordRulesManager.sys.mjs
@@ -0,0 +1,128 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+  PasswordGenerator: "resource://gre/modules/PasswordGenerator.sys.mjs",
+  PasswordRulesParser: "resource://gre/modules/PasswordRulesParser.sys.mjs",
+  RemoteSettings: "resource://services-settings/remote-settings.sys.mjs",
+});
+
+ChromeUtils.defineLazyGetter(lazy, "log", () => {
+  let logger = lazy.LoginHelper.createLogger("PasswordRulesManager");
+  return logger.log.bind(logger);
+});
+
+const IMPROVED_PASSWORD_GENERATION_HISTOGRAM =
+  "PWMGR_NUM_IMPROVED_GENERATED_PASSWORDS";
+
+/**
+ * Handles interactions between PasswordRulesParser and the "password-rules" Remote Settings collection
+ *
+ * @class PasswordRulesManagerParent
+ * @extends {JSWindowActorParent}
+ */
+export class PasswordRulesManagerParent extends JSWindowActorParent {
+  /**
+   * @type RemoteSettingsClient
+   *
+   * @memberof PasswordRulesManagerParent
+   */
+  _passwordRulesClient = null;
+
+  async initPasswordRulesCollection() {
+    if (!this._passwordRulesClient) {
+      this._passwordRulesClient = lazy.RemoteSettings(
+        lazy.LoginHelper.improvedPasswordRulesCollection
+      );
+    }
+  }
+  /**
+   * Transforms the parsed rules returned from PasswordRulesParser into a Map for easier access.
+   * The returned Map could have the following keys: "allowed", "required", "maxlength", "minlength", and "max-consecutive"
+   * @example
+   * // Returns a Map with a key-value pair of "allowed": "ascii-printable"
+   * _transformRulesToMap([{ _name: "allowed", value: [{ _name: "ascii-printable" }] }])
+   * @param {Object[]} rules rules from PasswordRulesParser.parsePasswordRules
+   * @return {Map} mapped rules
+   * @memberof PasswordRulesManagerParent
+   */
+  _transformRulesToMap(rules) {
+    let map = new Map();
+    for (let rule of rules) {
+      let { _name, value } = rule;
+      if (
+        _name === "minlength" ||
+        _name === "maxlength" ||
+        _name === "max-consecutive"
+      ) {
+        map.set(_name, value);
+      } else {
+        let _value = [];
+        if (map.get(_name)) {
+          _value = map.get(_name);
+        }
+        for (let _class of value) {
+          let { _name: _className } = _class;
+          if (_className) {
+            _value.push(_className);
+          } else {
+            let { _characters } = _class;
+            _value.push(_characters);
+          }
+        }
+        map.set(_name, _value);
+      }
+    }
+    return map;
+  }
+
+  /**
+   * Generates a password based on rules from the origin parameters.
+   * @param {nsIURI} uri
+   * @return {string} password
+   * @memberof PasswordRulesManagerParent
+   */
+  async generatePassword(uri, { inputMaxLength } = {}) {
+    await this.initPasswordRulesCollection();
+    let originDisplayHost = uri.displayHost;
+    let records = await this._passwordRulesClient.get();
+    let currentRecord;
+    for (let record of records) {
+      if (Services.eTLD.hasRootDomain(originDisplayHost, record.Domain)) {
+        currentRecord = record;
+        break;
+      }
+    }
+    let isCustomRule = false;
+    // If we found a matching result, use that to generate a stronger password.
+    // Otherwise, generate a password using the default rules set.
+    if (currentRecord?.Domain) {
+      isCustomRule = true;
+      lazy.log(
+        `Password rules for ${currentRecord.Domain}:  ${currentRecord["password-rules"]}.`
+      );
+      let currentRules = lazy.PasswordRulesParser.parsePasswordRules(
+        currentRecord["password-rules"]
+      );
+      let mapOfRules = this._transformRulesToMap(currentRules);
+      Services.telemetry
+        .getHistogramById(IMPROVED_PASSWORD_GENERATION_HISTOGRAM)
+        .add(isCustomRule);
+      return lazy.PasswordGenerator.generatePassword({
+        rules: mapOfRules,
+        inputMaxLength,
+      });
+    }
+    lazy.log(
+      `No password rules for specified origin, generating standard password.`
+    );
+    Services.telemetry
+      .getHistogramById(IMPROVED_PASSWORD_GENERATION_HISTOGRAM)
+      .add(isCustomRule);
+    return lazy.PasswordGenerator.generatePassword({ inputMaxLength });
+  }
+}
diff --git a/toolkit/components/passwordmgr/PasswordRulesParser.sys.mjs b/toolkit/components/passwordmgr/PasswordRulesParser.sys.mjs
new file mode 100644
index 0000000000..8ce7cba990
--- /dev/null
+++ b/toolkit/components/passwordmgr/PasswordRulesParser.sys.mjs
@@ -0,0 +1,695 @@
+// Sourced from https://github.com/apple/password-manager-resources/blob/5f6da89483e75cdc4165a6fc4756796e0ced7a21/tools/PasswordRulesParser.js
+// Copyright (c) 2019 - 2020 Apple Inc. Licensed under MIT License.
+
+export const PasswordRulesParser = {
+  parsePasswordRules,
+};
+
+const Identifier = {
+  ASCII_PRINTABLE: "ascii-printable",
+  DIGIT: "digit",
+  LOWER: "lower",
+  SPECIAL: "special",
+  UNICODE: "unicode",
+  UPPER: "upper",
+};
+
+const RuleName = {
+  ALLOWED: "allowed",
+  MAX_CONSECUTIVE: "max-consecutive",
+  REQUIRED: "required",
+  MIN_LENGTH: "minlength",
+  MAX_LENGTH: "maxlength",
+};
+
+const CHARACTER_CLASS_START_SENTINEL = "[";
+const CHARACTER_CLASS_END_SENTINEL = "]";
+const PROPERTY_VALUE_SEPARATOR = ",";
+const PROPERTY_SEPARATOR = ";";
+const PROPERTY_VALUE_START_SENTINEL = ":";
+
+const SPACE_CODE_POINT = " ".codePointAt(0);
+
+const SHOULD_NOT_BE_REACHED = "Should not be reached";
+
+class Rule {
+  constructor(name, value) {
+    this._name = name;
+    this.value = value;
+  }
+  get name() {
+    return this._name;
+  }
+  toString() {
+    return JSON.stringify(this);
+  }
+}
+
+class NamedCharacterClass {
+  constructor(name) {
+    console.assert(_isValidRequiredOrAllowedPropertyValueIdentifier(name));
+    this._name = name;
+  }
+  get name() {
+    return this._name.toLowerCase();
+  }
+  toString() {
+    return this._name;
+  }
+  toHTMLString() {
+    return this._name;
+  }
+}
+
+class CustomCharacterClass {
+  constructor(characters) {
+    console.assert(characters instanceof Array);
+    this._characters = characters;
+  }
+  get characters() {
+    return this._characters;
+  }
+  toString() {
+    return `[${this._characters.join("")}]`;
+  }
+  toHTMLString() {
+    return `[${this._characters.join("").replace('"', "&quot;")}]`;
+  }
+}
+
+// MARK: Lexer functions
+
+function _isIdentifierCharacter(c) {
+  console.assert(c.length === 1);
+  return (c >= "a" && c <= "z") || (c >= "A" && c <= "Z") || c === "-";
+}
+
+function _isASCIIDigit(c) {
+  console.assert(c.length === 1);
+  return c >= "0" && c <= "9";
+}
+
+function _isASCIIPrintableCharacter(c) {
+  console.assert(c.length === 1);
+  return c >= " " && c <= "~";
+}
+
+function _isASCIIWhitespace(c) {
+  console.assert(c.length === 1);
+  return c === " " || c === "\f" || c === "\n" || c === "\r" || c === "\t";
+}
+
+// MARK: ASCII printable character bit set and canonicalization functions
+
+function _bitSetIndexForCharacter(c) {
+  console.assert(c.length == 1);
+  return c.codePointAt(0) - SPACE_CODE_POINT;
+}
+
+function _characterAtBitSetIndex(index) {
+  return String.fromCodePoint(index + SPACE_CODE_POINT);
+}
+
+function _markBitsForNamedCharacterClass(bitSet, namedCharacterClass) {
+  console.assert(bitSet instanceof Array);
+  console.assert(namedCharacterClass.name !== Identifier.UNICODE);
+  console.assert(namedCharacterClass.name !== Identifier.ASCII_PRINTABLE);
+  if (namedCharacterClass.name === Identifier.UPPER) {
+    bitSet.fill(
+      true,
+      _bitSetIndexForCharacter("A"),
+      _bitSetIndexForCharacter("Z") + 1
+    );
+  } else if (namedCharacterClass.name === Identifier.LOWER) {
+    bitSet.fill(
+      true,
+      _bitSetIndexForCharacter("a"),
+      _bitSetIndexForCharacter("z") + 1
+    );
+  } else if (namedCharacterClass.name === Identifier.DIGIT) {
+    bitSet.fill(
+      true,
+      _bitSetIndexForCharacter("0"),
+      _bitSetIndexForCharacter("9") + 1
+    );
+  } else if (namedCharacterClass.name === Identifier.SPECIAL) {
+    bitSet.fill(
+      true,
+      _bitSetIndexForCharacter(" "),
+      _bitSetIndexForCharacter("/") + 1
+    );
+    bitSet.fill(
+      true,
+      _bitSetIndexForCharacter(":"),
+      _bitSetIndexForCharacter("@") + 1
+    );
+    bitSet.fill(
+      true,
+      _bitSetIndexForCharacter("["),
+      _bitSetIndexForCharacter("`") + 1
+    );
+    bitSet.fill(
+      true,
+      _bitSetIndexForCharacter("{"),
+      _bitSetIndexForCharacter("~") + 1
+    );
+  } else {
+    console.assert(false, SHOULD_NOT_BE_REACHED, namedCharacterClass);
+  }
+}
+
+function _markBitsForCustomCharacterClass(bitSet, customCharacterClass) {
+  for (let character of customCharacterClass.characters) {
+    bitSet[_bitSetIndexForCharacter(character)] = true;
+  }
+}
+
+function _canonicalizedPropertyValues(
+  propertyValues,
+  keepCustomCharacterClassFormatCompliant
+) {
+  let asciiPrintableBitSet = new Array(
+    "~".codePointAt(0) - " ".codePointAt(0) + 1
+  );
+
+  for (let propertyValue of propertyValues) {
+    if (propertyValue instanceof NamedCharacterClass) {
+      if (propertyValue.name === Identifier.UNICODE) {
+        return [new NamedCharacterClass(Identifier.UNICODE)];
+      }
+
+      if (propertyValue.name === Identifier.ASCII_PRINTABLE) {
+        return [new NamedCharacterClass(Identifier.ASCII_PRINTABLE)];
+      }
+
+      _markBitsForNamedCharacterClass(asciiPrintableBitSet, propertyValue);
+    } else if (propertyValue instanceof CustomCharacterClass) {
+      _markBitsForCustomCharacterClass(asciiPrintableBitSet, propertyValue);
+    }
+  }
+
+  let charactersSeen = [];
+
+  function checkRange(start, end) {
+    let temp = [];
+    for (
+      let i = _bitSetIndexForCharacter(start);
+      i <= _bitSetIndexForCharacter(end);
+      ++i
+    ) {
+      if (asciiPrintableBitSet[i]) {
+        temp.push(_characterAtBitSetIndex(i));
+      }
+    }
+
+    let result =
+      temp.length ===
+      _bitSetIndexForCharacter(end) - _bitSetIndexForCharacter(start) + 1;
+    if (!result) {
+      charactersSeen = charactersSeen.concat(temp);
+    }
+    return result;
+  }
+
+  let hasAllUpper = checkRange("A", "Z");
+  let hasAllLower = checkRange("a", "z");
+  let hasAllDigits = checkRange("0", "9");
+
+  // Check for special characters, accounting for characters that are given special treatment (i.e. '-' and ']')
+  let hasAllSpecial = false;
+  let hasDash = false;
+  let hasRightSquareBracket = false;
+  let temp = [];
+  for (
+    let i = _bitSetIndexForCharacter(" ");
+    i <= _bitSetIndexForCharacter("/");
+    ++i
+  ) {
+    if (!asciiPrintableBitSet[i]) {
+      continue;
+    }
+
+    let character = _characterAtBitSetIndex(i);
+    if (keepCustomCharacterClassFormatCompliant && character === "-") {
+      hasDash = true;
+    } else {
+      temp.push(character);
+    }
+  }
+  for (
+    let i = _bitSetIndexForCharacter(":");
+    i <= _bitSetIndexForCharacter("@");
+    ++i
+  ) {
+    if (asciiPrintableBitSet[i]) {
+      temp.push(_characterAtBitSetIndex(i));
+    }
+  }
+  for (
+    let i = _bitSetIndexForCharacter("[");
+    i <= _bitSetIndexForCharacter("`");
+    ++i
+  ) {
+    if (!asciiPrintableBitSet[i]) {
+      continue;
+    }
+
+    let character = _characterAtBitSetIndex(i);
+    if (keepCustomCharacterClassFormatCompliant && character === "]") {
+      hasRightSquareBracket = true;
+    } else {
+      temp.push(character);
+    }
+  }
+  for (
+    let i = _bitSetIndexForCharacter("{");
+    i <= _bitSetIndexForCharacter("~");
+    ++i
+  ) {
+    if (asciiPrintableBitSet[i]) {
+      temp.push(_characterAtBitSetIndex(i));
+    }
+  }
+
+  if (hasDash) {
+    temp.unshift("-");
+  }
+  if (hasRightSquareBracket) {
+    temp.push("]");
+  }
+
+  let numberOfSpecialCharacters =
+    _bitSetIndexForCharacter("/") -
+    _bitSetIndexForCharacter(" ") +
+    1 +
+    (_bitSetIndexForCharacter("@") - _bitSetIndexForCharacter(":") + 1) +
+    (_bitSetIndexForCharacter("`") - _bitSetIndexForCharacter("[") + 1) +
+    (_bitSetIndexForCharacter("~") - _bitSetIndexForCharacter("{") + 1);
+  hasAllSpecial = temp.length === numberOfSpecialCharacters;
+  if (!hasAllSpecial) {
+    charactersSeen = charactersSeen.concat(temp);
+  }
+
+  let result = [];
+  if (hasAllUpper && hasAllLower && hasAllDigits && hasAllSpecial) {
+    return [new NamedCharacterClass(Identifier.ASCII_PRINTABLE)];
+  }
+  if (hasAllUpper) {
+    result.push(new NamedCharacterClass(Identifier.UPPER));
+  }
+  if (hasAllLower) {
+    result.push(new NamedCharacterClass(Identifier.LOWER));
+  }
+  if (hasAllDigits) {
+    result.push(new NamedCharacterClass(Identifier.DIGIT));
+  }
+  if (hasAllSpecial) {
+    result.push(new NamedCharacterClass(Identifier.SPECIAL));
+  }
+  if (charactersSeen.length) {
+    result.push(new CustomCharacterClass(charactersSeen));
+  }
+  return result;
+}
+
+// MARK: Parser functions
+
+function _indexOfNonWhitespaceCharacter(input, position = 0) {
+  console.assert(position >= 0);
+  console.assert(position <= input.length);
+
+  let length = input.length;
+  while (position < length && _isASCIIWhitespace(input[position])) {
+    ++position;
+  }
+
+  return position;
+}
+
+function _parseIdentifier(input, position) {
+  console.assert(position >= 0);
+  console.assert(position < input.length);
+  console.assert(_isIdentifierCharacter(input[position]));
+
+  let length = input.length;
+  let seenIdentifiers = [];
+  do {
+    let c = input[position];
+    if (!_isIdentifierCharacter(c)) {
+      break;
+    }
+
+    seenIdentifiers.push(c);
+    ++position;
+  } while (position < length);
+
+  return [seenIdentifiers.join(""), position];
+}
+
+function _isValidRequiredOrAllowedPropertyValueIdentifier(identifier) {
+  return (
+    identifier && Object.values(Identifier).includes(identifier.toLowerCase())
+  );
+}
+
+function _parseCustomCharacterClass(input, position) {
+  console.assert(position >= 0);
+  console.assert(position < input.length);
+  console.assert(input[position] === CHARACTER_CLASS_START_SENTINEL);
+
+  let length = input.length;
+  ++position;
+  if (position >= length) {
+    console.error("Found end-of-line instead of character class character");
+    return [null, position];
+  }
+
+  let initialPosition = position;
+  let result = [];
+  do {
+    let c = input[position];
+    if (!_isASCIIPrintableCharacter(c)) {
+      ++position;
+      continue;
+    }
+
+    if (c === "-" && position - initialPosition > 0) {
+      // FIXME: Should this be an error?
+      console.warn(
+        "Ignoring '-'; a '-' may only appear as the first character in a character class"
+      );
+      ++position;
+      continue;
+    }
+
+    result.push(c);
+    ++position;
+    if (c === CHARACTER_CLASS_END_SENTINEL) {
+      break;
+    }
+  } while (position < length);
+
+  if (
+    (position < length && input[position] !== CHARACTER_CLASS_END_SENTINEL) ||
+    (position == length && input[position - 1] == CHARACTER_CLASS_END_SENTINEL)
+  ) {
+    // Fix up result; we over consumed.
+    result.pop();
+    return [result, position];
+  }
+
+  if (position < length && input[position] == CHARACTER_CLASS_END_SENTINEL) {
+    return [result, position + 1];
+  }
+
+  console.error("Found end-of-line instead of end of character class");
+  return [null, position];
+}
+
+function _parsePasswordRequiredOrAllowedPropertyValue(input, position) {
+  console.assert(position >= 0);
+  console.assert(position < input.length);
+
+  let length = input.length;
+  let propertyValues = [];
+  while (true) {
+    if (_isIdentifierCharacter(input[position])) {
+      let identifierStartPosition = position;
+      var [propertyValue, position] = _parseIdentifier(input, position);
+      if (!_isValidRequiredOrAllowedPropertyValueIdentifier(propertyValue)) {
+        console.error(
+          "Unrecognized property value identifier: " + propertyValue
+        );
+        return [null, identifierStartPosition];
+      }
+      propertyValues.push(new NamedCharacterClass(propertyValue));
+    } else if (input[position] == CHARACTER_CLASS_START_SENTINEL) {
+      var [propertyValue, position] = _parseCustomCharacterClass(
+        input,
+        position
+      );
+      if (propertyValue && propertyValue.length) {
+        propertyValues.push(new CustomCharacterClass(propertyValue));
+      }
+    } else {
+      console.error(
+        "Failed to find start of property value: " + input.substr(position)
+      );
+      return [null, position];
+    }
+
+    position = _indexOfNonWhitespaceCharacter(input, position);
+    if (position >= length || input[position] === PROPERTY_SEPARATOR) {
+      break;
+    }
+
+    if (input[position] === PROPERTY_VALUE_SEPARATOR) {
+      position = _indexOfNonWhitespaceCharacter(input, position + 1);
+      if (position >= length) {
+        console.error(
+          "Found end-of-line instead of start of next property value"
+        );
+        return [null, position];
+      }
+      continue;
+    }
+
+    console.error(
+      "Failed to find start of next property or property value: " +
+        input.substr(position)
+    );
+    return [null, position];
+  }
+  return [propertyValues, position];
+}
+
+function _parsePasswordRule(input, position) {
+  console.assert(position >= 0);
+  console.assert(position < input.length);
+  console.assert(_isIdentifierCharacter(input[position]));
+
+  let length = input.length;
+
+  let mayBeIdentifierStartPosition = position;
+  var [identifier, position] = _parseIdentifier(input, position);
+  if (!Object.values(RuleName).includes(identifier)) {
+    console.error("Unrecognized property name: " + identifier);
+    return [null, mayBeIdentifierStartPosition];
+  }
+
+  if (position >= length) {
+    console.error("Found end-of-line instead of start of property value");
+    return [null, position];
+  }
+
+  if (input[position] !== PROPERTY_VALUE_START_SENTINEL) {
+    console.error(
+      "Failed to find start of property value: " + input.substr(position)
+    );
+    return [null, position];
+  }
+
+  let property = { name: identifier, value: null };
+
+  position = _indexOfNonWhitespaceCharacter(input, position + 1);
+  // Empty value
+  if (position >= length || input[position] === PROPERTY_SEPARATOR) {
+    return [new Rule(property.name, property.value), position];
+  }
+
+  switch (identifier) {
+    case RuleName.ALLOWED:
+    case RuleName.REQUIRED: {
+      var [
+        propertyValue,
+        position,
+      ] = _parsePasswordRequiredOrAllowedPropertyValue(input, position);
+      if (propertyValue) {
+        property.value = propertyValue;
+      }
+      return [new Rule(property.name, property.value), position];
+    }
+    case RuleName.MAX_CONSECUTIVE: {
+      var [propertyValue, position] = _parseMaxConsecutivePropertyValue(
+        input,
+        position
+      );
+      if (propertyValue) {
+        property.value = propertyValue;
+      }
+      return [new Rule(property.name, property.value), position];
+    }
+    case RuleName.MIN_LENGTH:
+    case RuleName.MAX_LENGTH: {
+      var [propertyValue, position] = _parseMinLengthMaxLengthPropertyValue(
+        input,
+        position
+      );
+      if (propertyValue) {
+        property.value = propertyValue;
+      }
+      return [new Rule(property.name, property.value), position];
+    }
+  }
+  console.assert(false, SHOULD_NOT_BE_REACHED);
+}
+
+function _parseMinLengthMaxLengthPropertyValue(input, position) {
+  return _parseInteger(input, position);
+}
+
+function _parseMaxConsecutivePropertyValue(input, position) {
+  return _parseInteger(input, position);
+}
+
+function _parseInteger(input, position) {
+  console.assert(position >= 0);
+  console.assert(position < input.length);
+
+  if (!_isASCIIDigit(input[position])) {
+    console.error(
+      "Failed to parse value of type integer; not a number: " +
+        input.substr(position)
+    );
+    return [null, position];
+  }
+
+  let length = input.length;
+  let initialPosition = position;
+  let result = 0;
+  do {
+    result = 10 * result + parseInt(input[position], 10);
+    ++position;
+  } while (
+    position < length &&
+    input[position] !== PROPERTY_SEPARATOR &&
+    _isASCIIDigit(input[position])
+  );
+
+  if (position >= length || input[position] === PROPERTY_SEPARATOR) {
+    return [result, position];
+  }
+
+  console.error(
+    "Failed to parse value of type integer; not a number: " +
+      input.substr(initialPosition)
+  );
+  return [null, position];
+}
+
+function _parsePasswordRulesInternal(input) {
+  let parsedProperties = [];
+  let length = input.length;
+
+  var position = _indexOfNonWhitespaceCharacter(input);
+  while (position < length) {
+    if (!_isIdentifierCharacter(input[position])) {
+      console.warn(
+        "Failed to find start of property: " + input.substr(position)
+      );
+      return parsedProperties;
+    }
+
+    var [parsedProperty, position] = _parsePasswordRule(input, position);
+    if (parsedProperty && parsedProperty.value) {
+      parsedProperties.push(parsedProperty);
+    }
+
+    position = _indexOfNonWhitespaceCharacter(input, position);
+    if (position >= length) {
+      break;
+    }
+
+    if (input[position] === PROPERTY_SEPARATOR) {
+      position = _indexOfNonWhitespaceCharacter(input, position + 1);
+      if (position >= length) {
+        return parsedProperties;
+      }
+
+      continue;
+    }
+
+    console.error(
+      "Failed to find start of next property: " + input.substr(position)
+    );
+    return null;
+  }
+
+  return parsedProperties;
+}
+
+function parsePasswordRules(input, formatRulesForMinifiedVersion) {
+  let passwordRules = _parsePasswordRulesInternal(input) || [];
+
+  // When formatting rules for minified version, we should keep the formatted rules
+  // as similar to the input as possible. Avoid copying required rules to allowed rules.
+  let suppressCopyingRequiredToAllowed = formatRulesForMinifiedVersion;
+
+  let newPasswordRules = [];
+  let newAllowedValues = [];
+  let minimumMaximumConsecutiveCharacters = null;
+  let maximumMinLength = 0;
+  let minimumMaxLength = null;
+
+  for (let rule of passwordRules) {
+    switch (rule.name) {
+      case RuleName.MAX_CONSECUTIVE:
+        minimumMaximumConsecutiveCharacters = minimumMaximumConsecutiveCharacters
+          ? Math.min(rule.value, minimumMaximumConsecutiveCharacters)
+          : rule.value;
+        break;
+
+      case RuleName.MIN_LENGTH:
+        maximumMinLength = Math.max(rule.value, maximumMinLength);
+        break;
+
+      case RuleName.MAX_LENGTH:
+        minimumMaxLength = minimumMaxLength
+          ? Math.min(rule.value, minimumMaxLength)
+          : rule.value;
+        break;
+
+      case RuleName.REQUIRED:
+        rule.value = _canonicalizedPropertyValues(
+          rule.value,
+          formatRulesForMinifiedVersion
+        );
+        newPasswordRules.push(rule);
+        if (!suppressCopyingRequiredToAllowed) {
+          newAllowedValues = newAllowedValues.concat(rule.value);
+        }
+        break;
+
+      case RuleName.ALLOWED:
+        newAllowedValues = newAllowedValues.concat(rule.value);
+        break;
+    }
+  }
+
+  newAllowedValues = _canonicalizedPropertyValues(
+    newAllowedValues,
+    suppressCopyingRequiredToAllowed
+  );
+  if (!suppressCopyingRequiredToAllowed && !newAllowedValues.length) {
+    newAllowedValues = [new NamedCharacterClass(Identifier.ASCII_PRINTABLE)];
+  }
+  if (newAllowedValues.length) {
+    newPasswordRules.push(new Rule(RuleName.ALLOWED, newAllowedValues));
+  }
+
+  if (minimumMaximumConsecutiveCharacters !== null) {
+    newPasswordRules.push(
+      new Rule(RuleName.MAX_CONSECUTIVE, minimumMaximumConsecutiveCharacters)
+    );
+  }
+
+  if (maximumMinLength > 0) {
+    newPasswordRules.push(new Rule(RuleName.MIN_LENGTH, maximumMinLength));
+  }
+
+  if (minimumMaxLength !== null) {
+    newPasswordRules.push(new Rule(RuleName.MAX_LENGTH, minimumMaxLength));
+  }
+
+  return newPasswordRules;
+}
diff --git a/toolkit/components/passwordmgr/components.conf b/toolkit/components/passwordmgr/components.conf
new file mode 100644
index 0000000000..4adb4c3b3f
--- /dev/null
+++ b/toolkit/components/passwordmgr/components.conf
@@ -0,0 +1,65 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+Classes = [
+    {
+        'js_name': 'logins',
+        'cid': '{cb9e0de8-3598-4ed7-857b-827f011ad5d8}',
+        'contract_ids': ['@mozilla.org/login-manager;1'],
+        'interfaces': ['nsILoginManager'],
+        'esModule': 'resource://gre/modules/LoginManager.sys.mjs',
+        'constructor': 'LoginManager',
+    },
+    {
+        'cid': '{749e62f4-60ae-4569-a8a2-de78b649660e}',
+        'contract_ids': ['@mozilla.org/passwordmanager/authpromptfactory;1'],
+        'esModule': 'resource://gre/modules/LoginManagerAuthPrompter.sys.mjs',
+        'constructor': 'LoginManagerAuthPromptFactory',
+    },
+    {
+        'cid': '{2bdac17c-53f1-4896-a521-682ccdeef3a8}',
+        'contract_ids': ['@mozilla.org/login-manager/autocompletesearch;1'],
+        'esModule': 'resource://gre/modules/LoginAutoComplete.sys.mjs',
+        'constructor': 'LoginAutoComplete',
+    },
+    {
+        'cid': '{8aa66d77-1bbb-45a6-991e-b8f47751c291}',
+        'contract_ids': ['@mozilla.org/login-manager/authprompter;1'],
+        'esModule': 'resource://gre/modules/LoginManagerAuthPrompter.sys.mjs',
+        'constructor': 'LoginManagerAuthPrompter',
+    },
+    {
+        'cid': '{0f2f347c-1e4f-40cc-8efd-792dea70a85e}',
+        'contract_ids': ['@mozilla.org/login-manager/loginInfo;1'],
+        'esModule': 'resource://gre/modules/LoginInfo.sys.mjs',
+        'constructor': 'nsLoginInfo',
+    },
+    {
+        'cid': '{dc6c2976-0f73-4f1f-b9ff-3d72b4e28309}',
+        'contract_ids': ['@mozilla.org/login-manager/crypto/SDR;1'],
+        'esModule': 'resource://gre/modules/crypto-SDR.sys.mjs',
+        'constructor': 'LoginManagerCrypto_SDR',
+    },
+]
+
+if buildconfig.substs['OS_TARGET'] != 'Android':
+     Classes += [
+        {
+            'cid': '{c47ff942-9678-44a5-bc9b-05e0d676c79c}',
+            'contract_ids': ['@mozilla.org/login-manager/prompter;1'],
+            'esModule': 'resource://gre/modules/LoginManagerPrompter.sys.mjs',
+            'constructor': 'LoginManagerPrompter',
+        },
+        {
+            'cid': '{dc185a77-ba88-4caa-8f16-465253f7599a}',
+            'contract_ids': [
+                '@mozilla.org/autocomplete/search;1?name=login-doorhanger-username',
+                '@mozilla.org/autocomplete/search;1?name=login-doorhanger-password'
+            ],
+            'esModule': 'resource://gre/modules/AutoCompleteSimpleSearch.sys.mjs',
+            'constructor': 'AutoCompleteSimpleSearch',
+        },
+    ]
diff --git a/toolkit/components/passwordmgr/crypto-SDR.sys.mjs b/toolkit/components/passwordmgr/crypto-SDR.sys.mjs
new file mode 100644
index 0000000000..3bdfecb2b3
--- /dev/null
+++ b/toolkit/components/passwordmgr/crypto-SDR.sys.mjs
@@ -0,0 +1,307 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+});
+
+export function LoginManagerCrypto_SDR() {
+  this.init();
+}
+
+LoginManagerCrypto_SDR.prototype = {
+  classID: Components.ID("{dc6c2976-0f73-4f1f-b9ff-3d72b4e28309}"),
+  QueryInterface: ChromeUtils.generateQI(["nsILoginManagerCrypto"]),
+
+  __decoderRing: null, // nsSecretDecoderRing service
+  get _decoderRing() {
+    if (!this.__decoderRing) {
+      this.__decoderRing = Cc["@mozilla.org/security/sdr;1"].getService(
+        Ci.nsISecretDecoderRing
+      );
+    }
+    return this.__decoderRing;
+  },
+
+  __utfConverter: null, // UCS2 <--> UTF8 string conversion
+  get _utfConverter() {
+    if (!this.__utfConverter) {
+      this.__utfConverter = Cc[
+        "@mozilla.org/intl/scriptableunicodeconverter"
+      ].createInstance(Ci.nsIScriptableUnicodeConverter);
+      this.__utfConverter.charset = "UTF-8";
+    }
+    return this.__utfConverter;
+  },
+
+  _utfConverterReset() {
+    this.__utfConverter = null;
+  },
+
+  _uiBusy: false,
+
+  init() {
+    // Check to see if the internal PKCS#11 token has been initialized.
+    // If not, set a blank password.
+    let tokenDB = Cc["@mozilla.org/security/pk11tokendb;1"].getService(
+      Ci.nsIPK11TokenDB
+    );
+
+    let token = tokenDB.getInternalKeyToken();
+    if (token.needsUserInit) {
+      this.log("Initializing key3.db with default blank password.");
+      token.initPassword("");
+    }
+  },
+
+  /*
+   * encrypt
+   *
+   * Encrypts the specified string, using the SecretDecoderRing.
+   *
+   * Returns the encrypted string, or throws an exception if there was a
+   * problem.
+   */
+  encrypt(plainText) {
+    let cipherText = null;
+
+    let wasLoggedIn = this.isLoggedIn;
+    let canceledMP = false;
+
+    this._uiBusy = !wasLoggedIn;
+    try {
+      let plainOctet = this._utfConverter.ConvertFromUnicode(plainText);
+      plainOctet += this._utfConverter.Finish();
+      cipherText = this._decoderRing.encryptString(plainOctet);
+    } catch (e) {
+      this.log(`Failed to encrypt string with error ${e.name}.`);
+      // If the user clicks Cancel, we get NS_ERROR_FAILURE.
+      // (unlike decrypting, which gets NS_ERROR_NOT_AVAILABLE).
+      if (e.result == Cr.NS_ERROR_FAILURE) {
+        canceledMP = true;
+        throw Components.Exception(
+          "User canceled primary password entry",
+          Cr.NS_ERROR_ABORT
+        );
+      } else {
+        throw Components.Exception(
+          "Couldn't encrypt string",
+          Cr.NS_ERROR_FAILURE
+        );
+      }
+    } finally {
+      this._uiBusy = false;
+      // If we triggered a primary password prompt, notify observers.
+      if (!wasLoggedIn && this.isLoggedIn) {
+        this._notifyObservers("passwordmgr-crypto-login");
+      } else if (canceledMP) {
+        this._notifyObservers("passwordmgr-crypto-loginCanceled");
+      }
+    }
+    return cipherText;
+  },
+
+  /*
+   * encryptMany
+   *
+   * Encrypts the specified strings, using the SecretDecoderRing.
+   *
+   * Returns a promise which resolves with the the encrypted strings,
+   * or throws/rejects with an error if there was a problem.
+   */
+  async encryptMany(plaintexts) {
+    if (!Array.isArray(plaintexts) || !plaintexts.length) {
+      throw Components.Exception(
+        "Need at least one plaintext to encrypt",
+        Cr.NS_ERROR_INVALID_ARG
+      );
+    }
+
+    let cipherTexts;
+
+    let wasLoggedIn = this.isLoggedIn;
+    let canceledMP = false;
+
+    this._uiBusy = !wasLoggedIn;
+    try {
+      cipherTexts = await this._decoderRing.asyncEncryptStrings(plaintexts);
+    } catch (e) {
+      this.log(`Failed to encrypt strings with error ${e.name}.`);
+      // If the user clicks Cancel, we get NS_ERROR_FAILURE.
+      // (unlike decrypting, which gets NS_ERROR_NOT_AVAILABLE).
+      if (e.result == Cr.NS_ERROR_FAILURE) {
+        canceledMP = true;
+        throw Components.Exception(
+          "User canceled primary password entry",
+          Cr.NS_ERROR_ABORT
+        );
+      } else {
+        throw Components.Exception(
+          "Couldn't encrypt strings",
+          Cr.NS_ERROR_FAILURE
+        );
+      }
+    } finally {
+      this._uiBusy = false;
+      // If we triggered a primary password prompt, notify observers.
+      if (!wasLoggedIn && this.isLoggedIn) {
+        this._notifyObservers("passwordmgr-crypto-login");
+      } else if (canceledMP) {
+        this._notifyObservers("passwordmgr-crypto-loginCanceled");
+      }
+    }
+    return cipherTexts;
+  },
+
+  /*
+   * decrypt
+   *
+   * Decrypts the specified string, using the SecretDecoderRing.
+   *
+   * Returns the decrypted string, or throws an exception if there was a
+   * problem.
+   */
+  decrypt(cipherText) {
+    let plainText = null;
+
+    let wasLoggedIn = this.isLoggedIn;
+    let canceledMP = false;
+
+    this._uiBusy = !wasLoggedIn;
+    try {
+      let plainOctet;
+      plainOctet = this._decoderRing.decryptString(cipherText);
+      plainText = this._utfConverter.ConvertToUnicode(plainOctet);
+    } catch (e) {
+      this.log(
+        `Failed to decrypt cipher text of length ${cipherText.length} with error ${e.name}.`
+      );
+
+      // In the unlikely event the converter threw, reset it.
+      this._utfConverterReset();
+
+      // If the user clicks Cancel, we get NS_ERROR_NOT_AVAILABLE.
+      // If the cipherText is bad / wrong key, we get NS_ERROR_FAILURE
+      // Wrong passwords are handled by the decoderRing reprompting;
+      // we get no notification.
+      if (e.result == Cr.NS_ERROR_NOT_AVAILABLE) {
+        canceledMP = true;
+        throw Components.Exception(
+          "User canceled primary password entry",
+          Cr.NS_ERROR_ABORT
+        );
+      } else {
+        throw Components.Exception(
+          "Couldn't decrypt string",
+          Cr.NS_ERROR_FAILURE
+        );
+      }
+    } finally {
+      this._uiBusy = false;
+      // If we triggered a primary password prompt, notify observers.
+      if (!wasLoggedIn && this.isLoggedIn) {
+        this._notifyObservers("passwordmgr-crypto-login");
+      } else if (canceledMP) {
+        this._notifyObservers("passwordmgr-crypto-loginCanceled");
+      }
+    }
+
+    return plainText;
+  },
+
+  /**
+   * Decrypts the specified strings, using the SecretDecoderRing.
+   *
+   * @resolve {string[]} The decrypted strings. If a string cannot
+   * be decrypted, the empty string is returned for that instance.
+   * Callers will need to use decrypt() to determine if the encrypted
+   * string is invalid or intentionally empty. Throws/reject with
+   * an error if there was a problem.
+   */
+  async decryptMany(cipherTexts) {
+    if (!Array.isArray(cipherTexts) || !cipherTexts.length) {
+      throw Components.Exception(
+        "Need at least one ciphertext to decrypt",
+        Cr.NS_ERROR_INVALID_ARG
+      );
+    }
+
+    let plainTexts = [];
+
+    let wasLoggedIn = this.isLoggedIn;
+    let canceledMP = false;
+
+    this._uiBusy = !wasLoggedIn;
+    try {
+      plainTexts = await this._decoderRing.asyncDecryptStrings(cipherTexts);
+    } catch (e) {
+      this.log(`Failed to decrypt strings with error ${e.name}.`);
+      // If the user clicks Cancel, we get NS_ERROR_NOT_AVAILABLE.
+      // If the cipherText is bad / wrong key, we get NS_ERROR_FAILURE
+      // Wrong passwords are handled by the decoderRing reprompting;
+      // we get no notification.
+      if (e.result == Cr.NS_ERROR_NOT_AVAILABLE) {
+        canceledMP = true;
+        throw Components.Exception(
+          "User canceled primary password entry",
+          Cr.NS_ERROR_ABORT
+        );
+      } else {
+        throw Components.Exception(
+          "Couldn't decrypt strings: " + e.result,
+          Cr.NS_ERROR_FAILURE
+        );
+      }
+    } finally {
+      this._uiBusy = false;
+      // If we triggered a primary password prompt, notify observers.
+      if (!wasLoggedIn && this.isLoggedIn) {
+        this._notifyObservers("passwordmgr-crypto-login");
+      } else if (canceledMP) {
+        this._notifyObservers("passwordmgr-crypto-loginCanceled");
+      }
+    }
+    return plainTexts;
+  },
+
+  /*
+   * uiBusy
+   */
+  get uiBusy() {
+    return this._uiBusy;
+  },
+
+  /*
+   * isLoggedIn
+   */
+  get isLoggedIn() {
+    let tokenDB = Cc["@mozilla.org/security/pk11tokendb;1"].getService(
+      Ci.nsIPK11TokenDB
+    );
+    let token = tokenDB.getInternalKeyToken();
+    return !token.hasPassword || token.isLoggedIn();
+  },
+
+  /*
+   * defaultEncType
+   */
+  get defaultEncType() {
+    return Ci.nsILoginManagerCrypto.ENCTYPE_SDR;
+  },
+
+  /*
+   * _notifyObservers
+   */
+  _notifyObservers(topic) {
+    this.log(`Prompted for a primary password, notifying for ${topic}`);
+    Services.obs.notifyObservers(null, topic);
+  },
+}; // end of nsLoginManagerCrypto_SDR implementation
+
+ChromeUtils.defineLazyGetter(LoginManagerCrypto_SDR.prototype, "log", () => {
+  let logger = lazy.LoginHelper.createLogger("Login crypto");
+  return logger.log.bind(logger);
+});
diff --git a/toolkit/components/passwordmgr/jar.mn b/toolkit/components/passwordmgr/jar.mn
new file mode 100644
index 0000000000..f5d3419990
--- /dev/null
+++ b/toolkit/components/passwordmgr/jar.mn
@@ -0,0 +1,12 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+toolkit.jar:
+%   content passwordmgr %content/passwordmgr/
+% resource passwordmgr %passwordmgr/
+#ifdef ANDROID
+  passwordmgr/passwordstorage.sys.mjs (./storage-geckoview.sys.mjs)
+#else
+  passwordmgr/passwordstorage.sys.mjs (./storage-desktop.sys.mjs)
+#endif
diff --git a/toolkit/components/passwordmgr/metrics.yaml b/toolkit/components/passwordmgr/metrics.yaml
new file mode 100644
index 0000000000..a524d10d9b
--- /dev/null
+++ b/toolkit/components/passwordmgr/metrics.yaml
@@ -0,0 +1,41 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# Adding a new metric? We have docs for that!
+# https://firefox-source-docs.mozilla.org/toolkit/components/glean/user/new_definitions_file.html
+
+---
+$schema: moz://mozilla.org/schemas/glean/metrics/2-0-0
+$tags:
+  - 'Toolkit :: Password Manager'
+
+pwmgr:
+  form_autofill_result:
+    type: labeled_counter
+    description:
+      The result of auto-filling a login form.
+    labels:
+      - filled
+      - no_password_field
+      - password_disabled_readonly
+      - no_logins_fit
+      - no_saved_logins
+      - existing_password
+      - existing_username
+      - multiple_logins
+      - no_autofill_forms
+      - autocomplete_off
+      - insecure
+      - password_autocomplete_new_password
+      - type_no_longer_password
+      - form_in_crossorigin_subframe
+      - filled_username_only_form
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1340021
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1833398
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1833398#c3
+    notification_emails:
+      - passwords-dev@mozilla.org
+    expires: never
diff --git a/toolkit/components/passwordmgr/moz.build b/toolkit/components/passwordmgr/moz.build
new file mode 100644
index 0000000000..4fbb9dcbf4
--- /dev/null
+++ b/toolkit/components/passwordmgr/moz.build
@@ -0,0 +1,79 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+if CONFIG["MOZ_BUILD_APP"] == "browser":
+    DEFINES["MOZ_BUILD_APP_IS_BROWSER"] = True
+
+MOCHITEST_MANIFESTS += ["test/mochitest/mochitest.toml"]
+BROWSER_CHROME_MANIFESTS += ["test/browser/browser.toml"]
+XPCSHELL_TESTS_MANIFESTS += ["test/unit/xpcshell.toml"]
+
+TESTING_JS_MODULES += [
+    "test/LoginTestUtils.sys.mjs",
+]
+
+XPIDL_SOURCES += [
+    "nsILoginAutoCompleteSearch.idl",
+    "nsILoginInfo.idl",
+    "nsILoginManager.idl",
+    "nsILoginManagerAuthPrompter.idl",
+    "nsILoginManagerCrypto.idl",
+    "nsILoginManagerPrompter.idl",
+    "nsILoginMetaInfo.idl",
+    "nsIPromptInstance.idl",
+]
+
+XPIDL_MODULE = "loginmgr"
+
+EXTRA_JS_MODULES += [
+    "crypto-SDR.sys.mjs",
+    "InsecurePasswordUtils.sys.mjs",
+    "LoginAutoComplete.sys.mjs",
+    "LoginFormFactory.sys.mjs",
+    "LoginHelper.sys.mjs",
+    "LoginInfo.sys.mjs",
+    "LoginManager.shared.mjs",
+    "LoginManager.sys.mjs",
+    "LoginManagerAuthPrompter.sys.mjs",
+    "LoginManagerChild.sys.mjs",
+    "LoginManagerParent.sys.mjs",
+    "LoginManagerPrompter.sys.mjs",
+    "LoginManagerTelemetry.sys.mjs",
+    "LoginRecipes.sys.mjs",
+    "LoginRelatedRealms.sys.mjs",
+    "NewPasswordModel.sys.mjs",
+    "PasswordGenerator.sys.mjs",
+    "PasswordRulesManager.sys.mjs",
+    "PasswordRulesParser.sys.mjs",
+    "storage-json.sys.mjs",
+]
+
+if CONFIG["OS_TARGET"] != "Android":
+    EXTRA_JS_MODULES += [
+        "CSV.sys.mjs",
+        "LoginCSVImport.sys.mjs",
+        "LoginExport.sys.mjs",
+        "LoginStore.sys.mjs",
+    ]
+
+if CONFIG["OS_TARGET"] == "WINNT":
+    EXTRA_JS_MODULES += [
+        "OSCrypto_win.sys.mjs",
+    ]
+
+if CONFIG["MOZ_BUILD_APP"] == "browser" or CONFIG["MOZ_SUITE"]:
+    EXTRA_JS_MODULES += [
+        "LoginManagerContextMenu.sys.mjs",
+    ]
+
+XPCOM_MANIFESTS += [
+    "components.conf",
+]
+
+JAR_MANIFESTS += ["jar.mn"]
+
+with Files("**"):
+    BUG_COMPONENT = ("Toolkit", "Password Manager")
diff --git a/toolkit/components/passwordmgr/nsILoginAutoCompleteSearch.idl b/toolkit/components/passwordmgr/nsILoginAutoCompleteSearch.idl
new file mode 100644
index 0000000000..6c0e94b445
--- /dev/null
+++ b/toolkit/components/passwordmgr/nsILoginAutoCompleteSearch.idl
@@ -0,0 +1,31 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIAutoCompleteResult;
+interface nsIFormAutoCompleteObserver;
+
+webidl HTMLInputElement;
+
+[scriptable, uuid(2bdac17c-53f1-4896-a521-682ccdeef3a8)]
+interface nsILoginAutoCompleteSearch : nsISupports {
+  /**
+   * Generate results for a login field autocomplete menu.
+   *
+   * NOTE: This interface is provided for use only by the FormFillController,
+   *       which calls it directly. This isn't really ideal, it should
+   *       probably be callback registered through the FFC.
+   * NOTE: This API is different than nsIAutoCompleteSearch.
+   */
+  void startSearch(in AString aSearchString,
+                   in nsIAutoCompleteResult aPreviousResult,
+                   in HTMLInputElement aElement,
+                   in nsIFormAutoCompleteObserver aListener);
+
+  /**
+   * Stop a previously-started search.
+   */
+  void stopSearch();
+};
diff --git a/toolkit/components/passwordmgr/nsILoginInfo.idl b/toolkit/components/passwordmgr/nsILoginInfo.idl
new file mode 100644
index 0000000000..93f4e2808d
--- /dev/null
+++ b/toolkit/components/passwordmgr/nsILoginInfo.idl
@@ -0,0 +1,160 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#include "nsISupports.idl"
+
+/**
+ * An object containing information for a login stored by the
+ * password manager.
+ */
+[scriptable, uuid(c41b7dff-6b9b-42fe-b78d-113051facb05)]
+interface nsILoginInfo : nsISupports {
+  /**
+   * A string to display to the user for the origin which includes the httpRealm,
+   * where applicable.
+   * e.g. "site.com", "site.com:1234", or "site.com (My Secure Realm)"
+   */
+  readonly attribute AString displayOrigin;
+
+  /**
+   * The origin the login applies to.
+   *
+   * For example,
+   * "https://site.com", "http://site.com:1234", "ftp://ftp.site.com",
+   * "moz-proxy://127.0.0.1:8888, "chrome://FirefoxAccounts", "file://".
+   */
+  attribute AString origin;
+
+  /**
+   * The origin the login applies to, incorrectly called a hostname.
+   * @deprecated in favor of `origin`
+   */
+  attribute AString hostname;
+
+  /**
+   * The origin a form-based login was submitted to.
+   *
+   * For logins obtained from HTML forms, this field is the origin of the |action|
+   * attribute from the |form| element. For
+   * example "http://www.site.com". [Forms with no |action| attribute
+   * default to submitting to their origin URL, so we store that.]
+   *
+   * For logins obtained from a HTTP or FTP protocol authentication,
+   * this field is NULL.
+   */
+  attribute AString formActionOrigin;
+
+  /**
+   * The origin a form-based login was submitted to, incorrectly referred to as a URL.
+   * @deprecated in favor of `formActionOrigin`
+   */
+  attribute AString formSubmitURL;
+
+  /**
+   * The HTTP Realm a login was requested for.
+   *
+   * When an HTTP server sends a 401 result, the WWW-Authenticate
+   * header includes a realm to identify the "protection space." See
+   * RFC2617. If the response sent has a missing or blank realm, the
+   * hostname is used instead.
+   *
+   * For logins obtained from HTML forms, this field is NULL.
+   */
+  attribute AString httpRealm;
+
+  /**
+   * The username for the login.
+   */
+  attribute AString username;
+
+  /**
+   * The |name| attribute for the username input field.
+   *
+   * For logins obtained from a HTTP or FTP protocol authentication,
+   * this field is an empty string.
+   *
+   * @note This attribute is currently saved but not used.
+   */
+  attribute AString usernameField;
+
+  /**
+   * The password for the login.
+   */
+  attribute AString password;
+
+  /**
+   * The |name| attribute for the password input field.
+   *
+   * For logins obtained from a HTTP or FTP protocol authentication,
+   * this field is an empty string.
+   *
+   * @note This attribute is currently saved but not used.
+   */
+  attribute AString passwordField;
+
+  /**
+   * Unknown fields this client doesn't know about but will be roundtripped
+   * for other clients to prevent data loss
+   */
+  attribute AString unknownFields;
+
+  /**
+   * True if the login has ever been synced at some point.
+   */
+  attribute boolean everSynced;
+
+  /**
+   * A counter used to indicate that syncing is occuring. It will get restored to 0
+   * once syncing is complete.
+   */
+  attribute long syncCounter;
+
+  /**
+   * Initialize a newly created nsLoginInfo object.
+   *
+   * The arguments are the fields for the new object.
+   */
+  void init(in AString aOrigin,
+            in AString aFormActionOrigin, in AString aHttpRealm,
+            in AString aUsername,      in AString aPassword,
+            [optional] in AString aUsernameField, [optional] in AString aPasswordField);
+
+  /**
+   * Test for strict equality with another nsILoginInfo object.
+   *
+   * @param aLoginInfo
+   *        The other object to test.
+   */
+  boolean equals(in nsILoginInfo aLoginInfo);
+
+  /**
+   * Test for loose equivalency with another nsILoginInfo object. The
+   * passwordField and usernameField values are ignored, and the password
+   * values may be optionally ignored. If one login's formSubmitURL is an
+   * empty string (but not null), it will be treated as a wildcard. [The
+   * blank value indicates the login was stored before bug 360493 was fixed.]
+   *
+   * @param aLoginInfo
+   *        The other object to test.
+   * @param ignorePassword
+   *        If true, ignore the password when checking for match.
+   */
+  boolean matches(in nsILoginInfo aLoginInfo, in boolean ignorePassword);
+
+  /**
+   * Create an identical copy of the login, duplicating all of the login's
+   * nsILoginInfo and nsILoginMetaInfo properties.
+   *
+   * This allows code to be forwards-compatible, when additional properties
+   * are added to nsILoginMetaInfo (or nsILoginInfo) in the future.
+   */
+  nsILoginInfo clone();
+};
+
+%{C++
+
+#define NS_LOGININFO_CONTRACTID "@mozilla.org/login-manager/loginInfo;1"
+
+%}
diff --git a/toolkit/components/passwordmgr/nsILoginManager.idl b/toolkit/components/passwordmgr/nsILoginManager.idl
new file mode 100644
index 0000000000..d9c1571485
--- /dev/null
+++ b/toolkit/components/passwordmgr/nsILoginManager.idl
@@ -0,0 +1,326 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsILoginInfo;
+interface nsIPropertyBag;
+
+[scriptable, uuid(43429075-ede6-41eb-ac69-a8cd4376b041)]
+interface nsILoginSearchCallback : nsISupports
+{
+  /**
+   * Called when a search is complete and the results are ready.
+   *
+   * @param aLogins
+   *        Logins found in the search.
+   */
+  void onSearchComplete(in Array<nsILoginInfo> aLogins);
+};
+
+[scriptable, uuid(38c7f6af-7df9-49c7-b558-2776b24e6cc1)]
+interface nsILoginManager : nsISupports {
+  /**
+   * This promise is resolved when initialization is complete, and is rejected
+   * in case initialization failed.  This includes the initial loading of the
+   * login data as well as any migration from previous versions.
+   *
+   * Calling any method of nsILoginManager before this promise is resolved
+   * might trigger the synchronous initialization fallback.
+   */
+  readonly attribute Promise initializationPromise;
+
+  /**
+   * Store a new login in the login manager.
+   *
+   * @param aLogin
+   *        The login to be added.
+   * @return a clone of the login info with the guid set (even if it was not provided)
+   *
+   * Default values for the login's nsILoginMetaInfo properties will be
+   * created. However, if the caller specifies non-default values, they will
+   * be used instead.
+   */
+  nsILoginInfo addLogin(in nsILoginInfo aLogin);
+
+  /**
+   * Like addLogin, but asynchronous.
+   *
+   * @param aLogin
+   *        The login to be added.
+   * @return A promise which resolves with a cloned login with the guid set.
+   *
+   * Default values for each login's nsILoginMetaInfo properties will be
+   * created. However, if the caller specifies non-default values, they will
+   * be used instead.
+   */
+  Promise addLoginAsync(in nsILoginInfo aLogin);
+
+  /**
+   * Like addLogin, but asynchronous and for many logins.
+   *
+   * @param aLogins
+   *        A JS Array of nsILoginInfos to add.
+   * @return A promise which resolves with a JS Array of cloned logins with
+   *         the guids set.
+   *
+   * Default values for each login's nsILoginMetaInfo properties will be
+   * created. However, if the caller specifies non-default values, they will
+   * be used instead.
+   */
+  Promise addLogins(in jsval aLogins);
+
+  /**
+   * Remove a login from the login manager.
+   *
+   * @param aLogin
+   *        The login to be removed.
+   *
+   * The specified login must exactly match a stored login. However, the
+   * values of any nsILoginMetaInfo properties are ignored.
+   */
+  void removeLogin(in nsILoginInfo aLogin);
+
+  /**
+   * Modify an existing login in the login manager.
+   *
+   * @param oldLogin
+   *        The login to be modified.
+   * @param newLoginData
+   *        The new login values (either a nsILoginInfo or nsIProperyBag)
+   *
+   * If newLoginData is a nsILoginInfo, all of the old login's nsILoginInfo
+   * properties are changed to the values from newLoginData (but the old
+   * login's nsILoginMetaInfo properties are unmodified).
+   *
+   * If newLoginData is a nsIPropertyBag, only the specified properties
+   * will be changed. The nsILoginMetaInfo properties of oldLogin can be
+   * changed in this manner.
+   *
+   * If the propertybag contains an item named "timesUsedIncrement", the
+   * login's timesUsed property will be incremented by the item's value.
+   */
+  void modifyLogin(in nsILoginInfo oldLogin, in nsISupports newLoginData);
+
+  /**
+   * Record that the password of a saved login was used (e.g. submitted or copied).
+   *
+   * @param {nsILoginInfo} aLogin
+   *        The login record of the password that was used.
+   * @param {boolean} aPrivateContextWithoutExplicitConsent
+   *        If the use was in private browsing AND without the user explicitly choosing to save/update.
+   *        Login use metadata will not be updated in this case but it will stil be counted for telemetry.
+   * @param {AString} aLoginType
+   *        One of "form_login", "form_password", "auth_login", or "prompt_login".
+   *        See saved_login_used in Events.yaml.
+   *        Don't assume that an auth. login is never used in a form and vice-versa. This argument
+   *        indicates the context of how it was used.
+   * @param {boolean} aFilled
+   *        Whether the login was filled, rather than being typed manually.
+   *
+   * If only the username was used, this method shouldn't be called as we don't
+   * want to double-count the use if both the username and password are copied.
+   * Copying of the username normally precedes the copying of the password anyways.
+   */
+  void recordPasswordUse(in nsILoginInfo aLogin, in boolean aPrivateContextWithoutExplicitConsent, in AString aLoginType, in boolean aFilled);
+
+  /**
+   * Remove all stored user facing logins.
+   *
+   * This will remove all the logins that a user can access through about:logins.
+   * This will not remove the FxA Sync key which is stored with the rest of a user's logins
+   * but is not accessible through about:logins
+   *
+   * The browser sanitization feature allows the user to clear any stored
+   * passwords. This interface allows that to be done without getting each
+   * login first.
+   *
+   */
+  void removeAllUserFacingLogins();
+
+  /**
+   * Completely remove all logins, including the user's FxA Sync key.
+   *
+   */
+  void removeAllLogins();
+
+  /**
+   * Fetch all logins in the login manager. An array is always returned;
+   * if there are no logins the array is empty. Decryption is handled in
+   * one batch.
+   *
+   * @return A promise which resolves with a JS Array of nsILoginInfo objects.
+   */
+  Promise getAllLogins();
+
+  /**
+   * Like getAllLogins, but with a callback returning the search results.
+   *
+   * @param {nsILoginSearchCallback} aCallback
+   *        The interface to notify when the search is complete.
+   *
+   */
+  void getAllLoginsWithCallback(in nsILoginSearchCallback aCallback);
+
+  /**
+   * Obtain a list of all origins for which password saving is disabled.
+   *
+   * @return An array of origin strings. For example: ["https://www.site.com"].
+   */
+  Array<AString> getAllDisabledHosts();
+
+  /**
+   * Check to see if saving logins has been disabled for an origin.
+   *
+   * @param aHost
+   *        The origin to check. For example: "http://foo.com".
+   */
+  boolean getLoginSavingEnabled(in AString aHost);
+
+  /**
+   * Disable (or enable) storing logins for the specified origin. When
+   * disabled, the login manager will not prompt to store logins for
+   * that origin. Existing logins are not affected.
+   *
+   * @param aHost
+   *        The origin to set. For example: "http://foo.com".
+   * @param isEnabled
+   *        Specify if saving logins should be enabled (true) or
+   *        disabled (false)
+   */
+  void setLoginSavingEnabled(in AString aHost, in boolean isEnabled);
+
+  /**
+   * Search for logins matching the specified criteria. Called when looking
+   * for logins that might be applicable to a form or authentication request.
+   *
+   * @deprecated Use `searchLoginsAsync` instead. This function is retained
+   * for Thunderbird compatibility.
+   *
+   * @param aOrigin
+   *        The origin to restrict searches to. For example: "http://www.site.com".
+   *        To find logins for a given nsIURI, you would typically pass in
+   *        its prePath (excluding userPass).
+   * @param aActionOrigin
+   *        For form logins, this argument should be the origin to which the
+   *        form will be submitted, not the whole URL.
+   *        For HTTP auth. logins, specify null.
+   *        An empty string ("") will match any value (except null).
+   * @param aHttpRealm
+   *        For HTTP auth. logins, this argument should be the HTTP Realm
+   *        for which the login applies. This is obtained from the
+   *        WWW-Authenticate header. See RFC2617. For form logins,
+   *        specify null.
+   *        An empty string ("") will match any value (except null).
+   * @return An array of nsILoginInfo objects.
+   */
+  Array<nsILoginInfo> findLogins(in AString aOrigin, in AString aActionOrigin,
+                                 in AString aHttpRealm);
+
+  /**
+   * Search for logins matching the specified criteria, as with
+   * findLogins(). This interface only returns the number of matching
+   * logins (and not the logins themselves), which allows a caller to
+   * check for logins without causing the user to be prompted for a primary
+   * password to decrypt the logins.
+   *
+   * @param aOrigin
+   *        The origin to restrict searches to. Specify an empty string
+   *        to match all origins. A null value will not match any logins, and
+   *        will thus always return a count of 0.
+   * @param aActionOrigin
+   *        The origin to which a form login will be submitted. To match any
+   *        form login, specify an empty string. To not match any form
+   *        login, specify null.
+   * @param aHttpRealm
+   *        The HTTP Realm for which the login applies. To match logins for
+   *        any realm, specify an empty string. To not match logins for any
+   *        realm, specify null.
+   */
+  unsigned long countLogins(in AString aOrigin, in AString aActionOrigin,
+                            in AString aHttpRealm);
+
+  /**
+   * Asynchonously search for logins in the login manager. The Promise always
+   * resolves to an array; if there are no logins the array is empty.
+   *
+   * @param {object} matchData
+   *        The data used to search as a JS object. This does not follow the same
+   *        requirements as findLogins for those fields. Wildcard matches are
+   *        simply not specified. If a `guid` is specified then no other properties
+   *        are used (outside of GeckoView).
+   * @return A promise resolving to an array of nsILoginInfo objects.
+   */
+  Promise searchLoginsAsync(in jsval matchData);
+
+  /**
+   * Search for logins in the login manager. An array is always returned;
+   * if there are no logins the array is empty.
+   * @deprecated New code should use `searchLoginsAsync`.
+   *             Only autocomplete, prompt, and test code still use this.
+   *
+   * @param matchData
+   *        The data used to search. This does not follow the same
+   *        requirements as findLogins for those fields. Wildcard matches are
+   *        simply not specified. If a `guid` is specified then no other properties
+   *        are used (outside of GeckoView).
+   * @return An array of nsILoginInfo objects.
+   */
+  Array<nsILoginInfo> searchLogins(in nsIPropertyBag matchData);
+
+  /**
+   * Returns the "sync id" used by Sync to know whether the store is current with
+   * respect to the sync servers.
+   *
+   * Returns null if the data doesn't exist or if the data can't be
+   * decrypted (including if the primary-password prompt is cancelled). This is
+   * OK for Sync as it can't even begin syncing if the primary-password is
+   * locked as the sync encrytion keys are stored in this login manager.
+   */
+  Promise getSyncID();
+
+  /**
+   * Sets the "sync id" used by Sync to know whether the store is current with
+   * respect to the sync servers. May be set to null.
+   *
+   * Throws if the data can't be encrypted (including if the primary-password
+   * prompt is cancelled)
+   */
+  Promise setSyncID(in AString syncID);
+
+  /**
+   * Returns the timestamp of the last sync as a double (in seconds since Epoch
+   * rounded to two decimal places), or 0.0 if the data doesn't exist.
+   */
+  Promise getLastSync();
+
+  /**
+   * Sets the timestamp of the last sync.
+   */
+  Promise setLastSync(in double timestamp);
+
+  /**
+   * Ensures that the local sync ID for the engine matches the sync ID for
+   * the collection on the server. If they don't match, then we set
+    * the local sync ID to newSyncID and reset the last sync timestamp.
+   */
+  Promise ensureCurrentSyncID(in AString newSyncID);
+
+ /**
+  * True when a primary password prompt is being displayed.
+  */
+  readonly attribute boolean uiBusy;
+
+ /**
+  * True when the primary password has already been entered, and so a caller
+  * can ask for decrypted logins without triggering a prompt.
+  */
+  readonly attribute boolean isLoggedIn;
+};
+
+%{C++
+
+#define NS_LOGINMANAGER_CONTRACTID "@mozilla.org/login-manager;1"
+
+%}
diff --git a/toolkit/components/passwordmgr/nsILoginManagerAuthPrompter.idl b/toolkit/components/passwordmgr/nsILoginManagerAuthPrompter.idl
new file mode 100644
index 0000000000..422981a0a3
--- /dev/null
+++ b/toolkit/components/passwordmgr/nsILoginManagerAuthPrompter.idl
@@ -0,0 +1,44 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#include "nsISupports.idl"
+
+interface nsILoginInfo;
+interface nsIDOMWindow;
+
+webidl Element;
+
+[scriptable, uuid(425f73b9-b2db-4e8a-88c5-9ac2512934ce)]
+interface nsILoginManagerAuthPrompter : nsISupports {
+  /**
+   * Initialize the prompter. Must be called before using other interfaces.
+   *
+   * @param aWindow
+   *        The window in which the user is doing some login-related action that's
+   *        resulting in a need to prompt them for something. The prompt
+   *        will be associated with this window (or, if a notification bar
+   *        is being used, topmost opener in some cases).
+   *
+   *        aWindow can be null if there is no associated window, e.g. in a JSM
+   *        or Sandbox. In this case there will be no checkbox to save the login
+   *        since the window is needed to know if this is a private context.
+   *
+   *        If this window is a content window, the corresponding window and browser
+   *        elements will be calculated. If this window is a chrome window, the
+   *        corresponding browser element needs to be set using setBrowser.
+   */
+  void init(in nsIDOMWindow aWindow);
+
+  /**
+   * The browser this prompter is being created for.
+   * This is required if the init function received a chrome window as argument.
+   */
+  attribute Element browser;
+};
+%{C++
+
+#define NS_LOGINMANAGERAUTHPROMPTER_CONTRACTID "@mozilla.org/login-manager/authprompter/;1"
+
+%}
diff --git a/toolkit/components/passwordmgr/nsILoginManagerCrypto.idl b/toolkit/components/passwordmgr/nsILoginManagerCrypto.idl
new file mode 100644
index 0000000000..936228548a
--- /dev/null
+++ b/toolkit/components/passwordmgr/nsILoginManagerCrypto.idl
@@ -0,0 +1,89 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#include "nsISupports.idl"
+
+[scriptable, uuid(2030770e-542e-40cd-8061-cd9d4ad4227f)]
+interface nsILoginManagerCrypto : nsISupports {
+
+  const unsigned long ENCTYPE_BASE64 = 0; // obsolete
+  const unsigned long ENCTYPE_SDR = 1;
+
+  /**
+   * encrypt
+   *
+   * @param plainText
+   *        The string to be encrypted.
+   *
+   * Encrypts the specified string, returning the ciphertext value.
+   *
+   * NOTE: The current implemention of this inferface simply uses NSS/PSM's
+   * "Secret Decoder Ring" service. It is not recommended for general
+   * purpose encryption/decryption.
+   *
+   * Can throw if the user cancels entry of their primary password.
+   */
+  AString encrypt(in AString plainText);
+
+  /*
+   * encryptMany
+   *
+   * @param plainTexts
+   *        The strings to be encrypted.
+   *
+   * Encrypts the specified strings, similar to encrypt, but returning a promise
+   * which resolves with the the encrypted strings.
+   */
+  Promise encryptMany(in jsval plainTexts);
+
+  /**
+   * decrypt
+   *
+   * @param cipherText
+   *        The string to be decrypted.
+   *
+   * Decrypts the specified string, returning the plaintext value.
+   *
+   * Can throw if the user cancels entry of their primary password, or if the
+   * cipherText value can not be successfully decrypted (eg, if it was
+   * encrypted with some other key).
+   */
+  AString decrypt(in AString cipherText);
+
+  /**
+   * @param cipherTexts
+   *        The strings to be decrypted.
+   *
+   * Decrypts the specified strings, returning the plaintext values.
+   *
+   * Can throw if the user cancels entry of their primary password, or if the
+   * cipherText value can not be successfully decrypted (eg, if it was
+   * encrypted with some other key).
+   */
+  Promise decryptMany(in jsval cipherTexts);
+
+  /**
+   * uiBusy
+   *
+   * True when a primary password prompt is being displayed.
+   */
+  readonly attribute boolean uiBusy;
+
+  /**
+   * isLoggedIn
+   *
+   * Current login state of the token used for encryption. If the user is
+   * not logged in, performing a crypto operation will result in a primary
+   * password prompt.
+   */
+  readonly attribute boolean isLoggedIn;
+
+  /**
+   * defaultEncType
+   *
+   * Default encryption type used by an implementation of this interface.
+   */
+  readonly attribute unsigned long defaultEncType;
+};
diff --git a/toolkit/components/passwordmgr/nsILoginManagerPrompter.idl b/toolkit/components/passwordmgr/nsILoginManagerPrompter.idl
new file mode 100644
index 0000000000..4f244258c0
--- /dev/null
+++ b/toolkit/components/passwordmgr/nsILoginManagerPrompter.idl
@@ -0,0 +1,103 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#include "nsISupports.idl"
+#include "nsIPromptInstance.idl"
+
+interface nsILoginInfo;
+interface nsIDOMWindow;
+
+webidl Element;
+
+[scriptable, uuid(c47ff942-9678-44a5-bc9b-05e0d676c79c)]
+interface nsILoginManagerPrompter : nsISupports {
+
+  /**
+   * Ask the user if they want to save a login (Yes, Never, Not Now)
+   *
+   * @param aBrowser
+   *        The browser of the webpage request that triggered the prompt.
+   * @param aLogin
+   *        The login to be saved.
+   * @param dismissed
+   *        A boolean value indicating whether the save logins doorhanger should
+   *        be dismissed automatically when shown.
+   * @param notifySaved
+   *        A boolean value indicating whether the notification should indicate that
+   *        a login has been saved
+   * @param autoFilledLoginGuid
+   *        A string guid value for the login which was autofilled into the form
+   * @param possibleValues
+   *        Contains values from anything that we think, but are not sure, might be
+   *        a username or password.  Has two properties, 'usernames' and 'passwords'.
+   */
+  nsIPromptInstance promptToSavePassword(
+          in Element aBrowser,
+          in nsILoginInfo aLogin,
+          [optional] in boolean dismissed,
+          [optional] in boolean notifySaved,
+          [optional] in AString autoFilledLoginGuid,
+          [optional] in jsval possibleValues);
+
+  /**
+   * Ask the user if they want to change a login's password or username.
+   * If the user consents, modifyLogin() will be called.
+   *
+   * @param aBrowser
+   *        The browser of the webpage request that triggered the prompt.
+   * @param aOldLogin
+   *        The existing login (with the old password).
+   * @param aNewLogin
+   *        The new login.
+   * @param dismissed
+   *        A boolean value indicating whether the save logins doorhanger should
+   *        be dismissed automatically when shown.
+   * @param autoSavedLoginGuid
+   *        A string guid value for the old login to be removed if the changes
+   *        match it to a different login
+   * @param autoFilledLoginGuid
+   *        A string guid value for the login which was autofilled into the form
+   * @param possibleValues
+   *        Contains values from anything that we think, but are not sure, might be
+   *        a username or password.  Has two properties, 'usernames' and 'passwords'.
+   */
+  nsIPromptInstance promptToChangePassword(
+          in Element aBrowser,
+          in nsILoginInfo aOldLogin,
+          in nsILoginInfo aNewLogin,
+          [optional] in boolean dismissed,
+          [optional] in boolean notifySaved,
+          [optional] in AString autoSavedLoginGuid,
+          [optional] in AString autoFilledLoginGuid,
+          [optional] in jsval possibleValues);
+
+  /**
+   * Ask the user if they want to change the password for one of
+   * multiple logins, when the caller can't determine exactly which
+   * login should be changed. If the user consents, modifyLogin() will
+   * be called.
+   *
+   * @param aBrowser
+   *        The browser of the webpage request that triggered the prompt.
+   * @param logins
+   *        An array of existing logins.
+   * @param aNewLogin
+   *        The new login.
+   *
+   * Note: Because the caller does not know the username of the login
+   *       to be changed, aNewLogin.username and aNewLogin.usernameField
+   *       will be set (using the user's selection) before modifyLogin()
+   *       is called.
+   */
+  nsIPromptInstance promptToChangePasswordWithUsernames(
+          in Element aBrowser,
+          in Array<nsILoginInfo> logins,
+          in nsILoginInfo aNewLogin);
+};
+%{C++
+
+#define NS_LOGINMANAGERPROMPTER_CONTRACTID "@mozilla.org/login-manager/prompter/;1"
+
+%}
diff --git a/toolkit/components/passwordmgr/nsILoginMetaInfo.idl b/toolkit/components/passwordmgr/nsILoginMetaInfo.idl
new file mode 100644
index 0000000000..0d0c3ec0ea
--- /dev/null
+++ b/toolkit/components/passwordmgr/nsILoginMetaInfo.idl
@@ -0,0 +1,54 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#include "nsISupports.idl"
+
+/**
+ * An object containing metainfo for a login stored by the login manager.
+ *
+ * Code using login manager can generally ignore this interface. When adding
+ * logins, default value will be created. When modifying logins, these
+ * properties will be unchanged unless a change is explicitly requested [by
+ * using modifyLogin() with a nsIPropertyBag]. When deleting a login or
+ * comparing logins, these properties are ignored.
+ */
+[scriptable, uuid(20d8eb40-c494-497f-b2a6-aaa32f807ebd)]
+interface nsILoginMetaInfo : nsISupports {
+  /**
+   * The GUID to uniquely identify the login. This can be any arbitrary
+   * string, but a format as created by nsIUUIDGenerator is recommended.
+   * For example, "{d4e1a1f6-5ea0-40ee-bff5-da57982f21cf}"
+   *
+   * addLogin will generate a random value unless a value is provided.
+   *
+   * addLogin and modifyLogin will throw if the GUID already exists.
+   */
+  attribute AString guid;
+
+  /**
+   * The time, in Unix Epoch milliseconds, when the login was first created.
+   */
+  attribute unsigned long long timeCreated;
+
+  /**
+   * The time, in Unix Epoch milliseconds, when the login was last submitted
+   * in a form or used to begin an HTTP auth session.
+   */
+  attribute unsigned long long timeLastUsed;
+
+  /**
+   * The time, in Unix Epoch milliseconds, when the login was last modified.
+   *
+   * Contrary to what the name may suggest, this attribute takes into account
+   * not only the password but also the username attribute.
+   */
+  attribute unsigned long long timePasswordChanged;
+
+  /**
+   * The number of times the login was submitted in a form or used to begin
+   * an HTTP auth session.
+   */
+  attribute unsigned long timesUsed;
+};
diff --git a/toolkit/components/passwordmgr/nsIPromptInstance.idl b/toolkit/components/passwordmgr/nsIPromptInstance.idl
new file mode 100644
index 0000000000..04cf5c98cd
--- /dev/null
+++ b/toolkit/components/passwordmgr/nsIPromptInstance.idl
@@ -0,0 +1,17 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#include "nsISupports.idl"
+
+/**
+ * An object representing a prompt or doorhanger.
+ */
+[scriptable, uuid(889842e9-052c-46c9-99f3-f4a426571e38)]
+interface nsIPromptInstance : nsISupports {
+  /**
+   * Dismiss this prompt (e.g. because it's not relevant anymore).
+   */
+  void dismiss();
+};
diff --git a/toolkit/components/passwordmgr/storage-desktop.sys.mjs b/toolkit/components/passwordmgr/storage-desktop.sys.mjs
new file mode 100644
index 0000000000..eaa72ae4c8
--- /dev/null
+++ b/toolkit/components/passwordmgr/storage-desktop.sys.mjs
@@ -0,0 +1,20 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import { LoginManagerStorage_json } from "resource://gre/modules/storage-json.sys.mjs";
+
+export class LoginManagerStorage extends LoginManagerStorage_json {
+  static #storage = null;
+
+  static create(callback) {
+    if (!LoginManagerStorage.#storage) {
+      LoginManagerStorage.#storage = new LoginManagerStorage();
+      LoginManagerStorage.#storage.initialize().then(callback);
+    } else if (callback) {
+      callback();
+    }
+
+    return LoginManagerStorage.#storage;
+  }
+}
diff --git a/toolkit/components/passwordmgr/storage-geckoview.sys.mjs b/toolkit/components/passwordmgr/storage-geckoview.sys.mjs
new file mode 100644
index 0000000000..db2ef6d61b
--- /dev/null
+++ b/toolkit/components/passwordmgr/storage-geckoview.sys.mjs
@@ -0,0 +1,245 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * LoginManagerStorage implementation for GeckoView
+ */
+
+import { LoginManagerStorage_json } from "resource://gre/modules/storage-json.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  GeckoViewAutocomplete: "resource://gre/modules/GeckoViewAutocomplete.sys.mjs",
+  LoginEntry: "resource://gre/modules/GeckoViewAutocomplete.sys.mjs",
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+});
+
+export class LoginManagerStorage extends LoginManagerStorage_json {
+  static #storage = null;
+
+  static create(callback) {
+    if (!LoginManagerStorage.#storage) {
+      LoginManagerStorage.#storage = new LoginManagerStorage();
+      LoginManagerStorage.#storage.initialize().then(callback);
+    } else if (callback) {
+      callback();
+    }
+
+    return LoginManagerStorage.#storage;
+  }
+
+  get _crypto() {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  initialize() {
+    try {
+      return Promise.resolve();
+    } catch (e) {
+      this.log("Initialization failed:", e);
+      throw new Error("Initialization failed");
+    }
+  }
+
+  /**
+   * Internal method used by regression tests only.  It is called before
+   * replacing this storage module with a new instance.
+   */
+  terminate() {}
+
+  async addLoginsAsync(logins, continueOnDuplicates = false) {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  removeLogin(login) {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  modifyLogin(oldLogin, newLoginData) {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  recordPasswordUse(login) {
+    lazy.GeckoViewAutocomplete.onLoginPasswordUsed(
+      lazy.LoginEntry.fromLoginInfo(login)
+    );
+  }
+
+  /**
+   * Returns a promise resolving to an array of all saved logins that can be decrypted.
+   *
+   * @resolve {nsILoginInfo[]}
+   */
+  getAllLogins(includeDeleted) {
+    return this._getLoginsAsync({}, includeDeleted);
+  }
+
+  async searchLoginsAsync(matchData, includeDeleted) {
+    this.log(
+      `Searching for matching saved logins for origin: ${matchData.origin}`
+    );
+    return this._getLoginsAsync(matchData, includeDeleted);
+  }
+
+  _baseHostnameFromOrigin(origin) {
+    if (!origin) {
+      return null;
+    }
+
+    let originURI = Services.io.newURI(origin);
+    try {
+      return Services.eTLD.getBaseDomain(originURI);
+    } catch (ex) {
+      if (ex.result == Cr.NS_ERROR_HOST_IS_IP_ADDRESS) {
+        // `getBaseDomain` cannot handle IP addresses and `nsIURI` cannot return
+        // IPv6 hostnames with the square brackets so use `URL.hostname`.
+        return new URL(origin).hostname;
+      } else if (ex.result == Cr.NS_ERROR_INSUFFICIENT_DOMAIN_LEVELS) {
+        return originURI.asciiHost;
+      }
+      throw ex;
+    }
+  }
+
+  async _getLoginsAsync(matchData, includeDeleted) {
+    let baseHostname = this._baseHostnameFromOrigin(matchData.origin);
+
+    // Query all logins for the eTLD+1 and then filter the logins in _searchLogins
+    // so that we can handle the logic for scheme upgrades, subdomains, etc.
+    // Convert from the new shape to one which supports the legacy getters used
+    // by _searchLogins.
+    let candidateLogins = await lazy.GeckoViewAutocomplete.fetchLogins(
+      baseHostname
+    ).catch(_ => {
+      // No GV delegate is attached.
+    });
+
+    if (!candidateLogins) {
+      // May be undefined if there is no delegate attached to handle the request.
+      // Ignore the request.
+      return [];
+    }
+
+    let realMatchData = {};
+    let options = {};
+
+    if (matchData.guid) {
+      // Enforce GUID-based filtering when available, since the origin of the
+      // login may not match the origin of the form in the case of scheme
+      // upgrades.
+      realMatchData = { guid: matchData.guid };
+    } else {
+      for (let [name, value] of Object.entries(matchData)) {
+        switch (name) {
+          // Some property names aren't field names but are special options to
+          // affect the search.
+          case "acceptDifferentSubdomains":
+          case "schemeUpgrades": {
+            options[name] = value;
+            break;
+          }
+          default: {
+            realMatchData[name] = value;
+            break;
+          }
+        }
+      }
+    }
+
+    const [logins] = this._searchLogins(
+      realMatchData,
+      includeDeleted,
+      options,
+      candidateLogins.map(this._vanillaLoginToStorageLogin)
+    );
+    return logins;
+  }
+
+  /**
+   * Convert a modern decrypted vanilla login object to one expected from logins.json.
+   *
+   * The storage login is usually encrypted but not in this case, this aligns
+   * with the `_decryptLogins` method being a no-op.
+   *
+   * @param {object} vanillaLogin using `origin`/`formActionOrigin`/`username` properties.
+   * @returns {object} a vanilla login for logins.json using
+   *                   `hostname`/`formSubmitURL`/`encryptedUsername`.
+   */
+  _vanillaLoginToStorageLogin(vanillaLogin) {
+    return {
+      ...vanillaLogin,
+      hostname: vanillaLogin.origin,
+      formSubmitURL: vanillaLogin.formActionOrigin,
+      encryptedUsername: vanillaLogin.username,
+      encryptedPassword: vanillaLogin.password,
+    };
+  }
+
+  /**
+   * Use `searchLoginsAsync` instead.
+   */
+  searchLogins(matchData) {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  /**
+   * Removes all logins from storage.
+   */
+  removeAllLogins() {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  countLogins(origin, formActionOrigin, httpRealm) {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  get uiBusy() {
+    return false;
+  }
+
+  get isLoggedIn() {
+    return true;
+  }
+
+  /**
+   * GeckoView will encrypt the login itself.
+   */
+  _encryptLogin(login) {
+    return login;
+  }
+
+  /**
+   * GeckoView logins are already decrypted before this component receives them
+   * so this method is a no-op for this backend.
+   * @see _vanillaLoginToStorageLogin
+   */
+  _decryptLogins(logins) {
+    return logins;
+  }
+
+  /**
+   * Sync metadata, which isn't supported by GeckoView.
+   */
+  async getSyncID() {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  async setSyncID(syncID) {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  async getLastSync() {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  async setLastSync(timestamp) {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+}
+
+ChromeUtils.defineLazyGetter(LoginManagerStorage.prototype, "log", () => {
+  let logger = lazy.LoginHelper.createLogger("Login storage");
+  return logger.log.bind(logger);
+});
diff --git a/toolkit/components/passwordmgr/storage-json.sys.mjs b/toolkit/components/passwordmgr/storage-json.sys.mjs
new file mode 100644
index 0000000000..36cc1c3c88
--- /dev/null
+++ b/toolkit/components/passwordmgr/storage-json.sys.mjs
@@ -0,0 +1,1056 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * LoginManagerStorage implementation for the JSON back-end.
+ */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  FXA_PWDMGR_HOST: "resource://gre/modules/FxAccountsCommon.sys.mjs",
+  FXA_PWDMGR_REALM: "resource://gre/modules/FxAccountsCommon.sys.mjs",
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+  LoginStore: "resource://gre/modules/LoginStore.sys.mjs",
+});
+
+const SYNCABLE_LOGIN_FIELDS = [
+  // `nsILoginInfo` fields.
+  "hostname",
+  "formSubmitURL",
+  "httpRealm",
+  "username",
+  "password",
+  "usernameField",
+  "passwordField",
+
+  // `nsILoginMetaInfo` fields.
+  "timeCreated",
+  "timePasswordChanged",
+];
+
+// Compares two logins to determine if their syncable fields changed. The login
+// manager fires `modifyLogin` for changes to all fields, including ones we
+// don't sync. In particular, `timeLastUsed` changes shouldn't mark the login
+// for upload; otherwise, we might overwrite changed passwords before they're
+// downloaded (bug 973166).
+function isSyncableChange(oldLogin, newLogin) {
+  oldLogin.QueryInterface(Ci.nsILoginMetaInfo).QueryInterface(Ci.nsILoginInfo);
+  newLogin.QueryInterface(Ci.nsILoginMetaInfo).QueryInterface(Ci.nsILoginInfo);
+  return SYNCABLE_LOGIN_FIELDS.some(prop => oldLogin[prop] != newLogin[prop]);
+}
+
+// Returns true if the argument is for the FxA login.
+function isFXAHost(login) {
+  return login.hostname == lazy.FXA_PWDMGR_HOST;
+}
+
+export class LoginManagerStorage_json {
+  constructor() {
+    this.__crypto = null; // nsILoginManagerCrypto service
+    this.__decryptedPotentiallyVulnerablePasswords = null;
+  }
+
+  get _crypto() {
+    if (!this.__crypto) {
+      this.__crypto = Cc["@mozilla.org/login-manager/crypto/SDR;1"].getService(
+        Ci.nsILoginManagerCrypto
+      );
+    }
+    return this.__crypto;
+  }
+
+  get _decryptedPotentiallyVulnerablePasswords() {
+    if (!this.__decryptedPotentiallyVulnerablePasswords) {
+      this._store.ensureDataReady();
+      this.__decryptedPotentiallyVulnerablePasswords = [];
+      for (const potentiallyVulnerablePassword of this._store.data
+        .potentiallyVulnerablePasswords) {
+        const decryptedPotentiallyVulnerablePassword = this._crypto.decrypt(
+          potentiallyVulnerablePassword.encryptedPassword
+        );
+        this.__decryptedPotentiallyVulnerablePasswords.push(
+          decryptedPotentiallyVulnerablePassword
+        );
+      }
+    }
+    return this.__decryptedPotentiallyVulnerablePasswords;
+  }
+
+  initialize() {
+    try {
+      // Force initialization of the crypto module.
+      // See bug 717490 comment 17.
+      this._crypto;
+
+      let profileDir = Services.dirsvc.get("ProfD", Ci.nsIFile).path;
+
+      // Set the reference to LoginStore synchronously.
+      let jsonPath = PathUtils.join(profileDir, "logins.json");
+      let backupPath = "";
+      let loginsBackupEnabled = Services.prefs.getBoolPref(
+        "signon.backup.enabled"
+      );
+      if (loginsBackupEnabled) {
+        backupPath = PathUtils.join(profileDir, "logins-backup.json");
+      }
+      this._store = new lazy.LoginStore(jsonPath, backupPath);
+
+      return (async () => {
+        // Load the data asynchronously.
+        this.log(`Opening database at ${this._store.path}.`);
+        await this._store.load();
+      })().catch(console.error);
+    } catch (e) {
+      this.log(`Initialization failed ${e.name}.`);
+      throw new Error("Initialization failed");
+    }
+  }
+
+  /**
+   * Internal method used by regression tests only.  It is called before
+   * replacing this storage module with a new instance.
+   */
+  terminate() {
+    this._store._saver.disarm();
+    return this._store._save();
+  }
+
+  /**
+   * Returns the "sync id" used by Sync to know whether the store is current with
+   * respect to the sync servers. It is stored encrypted, but only so we
+   * can detect failure to decrypt (for example, a "reset" of the primary
+   * password will leave all logins alone, but they will fail to decrypt. We
+   * also want this metadata to be unavailable in that scenario)
+   *
+   * Returns null if the data doesn't exist or if the data can't be
+   * decrypted (including if the primary-password prompt is cancelled). This is
+   * OK for Sync as it can't even begin syncing if the primary-password is
+   * locked as the sync encrytion keys are stored in this login manager.
+   */
+  async getSyncID() {
+    await this._store.load();
+    if (!this._store.data.sync) {
+      return null;
+    }
+    let raw = this._store.data.sync.syncID;
+    try {
+      return raw ? this._crypto.decrypt(raw) : null;
+    } catch (e) {
+      if (e.result == Cr.NS_ERROR_FAILURE) {
+        this.log("Could not decrypt the syncID - returning null.");
+        return null;
+      }
+      // any other errors get re-thrown.
+      throw e;
+    }
+  }
+
+  async setSyncID(syncID) {
+    await this._store.load();
+    if (!this._store.data.sync) {
+      this._store.data.sync = {};
+    }
+    this._store.data.sync.syncID = syncID ? this._crypto.encrypt(syncID) : null;
+    this._store.saveSoon();
+  }
+
+  async getLastSync() {
+    await this._store.load();
+    if (!this._store.data.sync) {
+      return 0;
+    }
+    return this._store.data.sync.lastSync || 0.0;
+  }
+
+  async setLastSync(timestamp) {
+    await this._store.load();
+    if (!this._store.data.sync) {
+      this._store.data.sync = {};
+    }
+    this._store.data.sync.lastSync = timestamp;
+    this._store.saveSoon();
+  }
+
+  #incrementSyncCounter(login) {
+    login.syncCounter++;
+  }
+
+  async resetSyncCounter(guid, value) {
+    this._store.ensureDataReady();
+
+    // This will also find deleted items.
+    let login = this._store.data.logins.find(login => login.guid == guid);
+    if (login?.syncCounter > 0) {
+      login.syncCounter = Math.max(0, login.syncCounter - value);
+      login.everSynced = true;
+    }
+
+    this._store.saveSoon();
+  }
+
+  // Returns false if the login has marked as deleted or doesn't exist.
+  loginIsDeleted(guid) {
+    let login = this._store.data.logins.find(l => l.guid == guid);
+    return !!login?.deleted;
+  }
+
+  // Synrhronuously stores encrypted login, returns login clone with upserted
+  // uuid and updated timestamps
+  #addLogin(login) {
+    this._store.ensureDataReady();
+
+    // Throws if there are bogus values.
+    lazy.LoginHelper.checkLoginValues(login);
+
+    // Clone the login, so we don't modify the caller's object.
+    let loginClone = login.clone();
+
+    // Initialize the nsILoginMetaInfo fields, unless the caller gave us values
+    loginClone.QueryInterface(Ci.nsILoginMetaInfo);
+    if (loginClone.guid) {
+      let guid = loginClone.guid;
+      if (!this._isGuidUnique(guid)) {
+        // We have an existing GUID, but it's possible that entry is unable
+        // to be decrypted - if that's the case we remove the existing one
+        // and allow this one to be added.
+        let existing = this._searchLogins({ guid })[0];
+        if (this._decryptLogins(existing).length) {
+          // Existing item is good, so it's an error to try and re-add it.
+          throw new Error("specified GUID already exists");
+        }
+        // find and remove the existing bad entry.
+        let foundIndex = this._store.data.logins.findIndex(l => l.guid == guid);
+        if (foundIndex == -1) {
+          throw new Error("can't find a matching GUID to remove");
+        }
+        this._store.data.logins.splice(foundIndex, 1);
+      }
+    } else {
+      loginClone.guid = Services.uuid.generateUUID().toString();
+    }
+
+    // Set timestamps
+    let currentTime = Date.now();
+    if (!loginClone.timeCreated) {
+      loginClone.timeCreated = currentTime;
+    }
+    if (!loginClone.timeLastUsed) {
+      loginClone.timeLastUsed = currentTime;
+    }
+    if (!loginClone.timePasswordChanged) {
+      loginClone.timePasswordChanged = currentTime;
+    }
+    if (!loginClone.timesUsed) {
+      loginClone.timesUsed = 1;
+    }
+
+    // If the everSynced is already set, then this login is an incoming
+    // sync record, so there is no need to mark this as needed to be synced.
+    if (!loginClone.everSynced && !isFXAHost(loginClone)) {
+      this.#incrementSyncCounter(loginClone);
+    }
+
+    this._store.data.logins.push({
+      id: this._store.data.nextId++,
+      hostname: loginClone.origin,
+      httpRealm: loginClone.httpRealm,
+      formSubmitURL: loginClone.formActionOrigin,
+      usernameField: loginClone.usernameField,
+      passwordField: loginClone.passwordField,
+      encryptedUsername: loginClone.username,
+      encryptedPassword: loginClone.password,
+      guid: loginClone.guid,
+      encType: this._crypto.defaultEncType,
+      timeCreated: loginClone.timeCreated,
+      timeLastUsed: loginClone.timeLastUsed,
+      timePasswordChanged: loginClone.timePasswordChanged,
+      timesUsed: loginClone.timesUsed,
+      syncCounter: loginClone.syncCounter,
+      everSynced: loginClone.everSynced,
+      encryptedUnknownFields: loginClone.unknownFields,
+    });
+    this._store.saveSoon();
+
+    return loginClone;
+  }
+
+  async addLoginsAsync(logins, continueOnDuplicates = false) {
+    if (logins.length === 0) {
+      return logins;
+    }
+
+    const encryptedLogins = await this.#encryptLogins(logins);
+
+    const resultLogins = [];
+    for (const [login, encryptedLogin] of encryptedLogins) {
+      // check for duplicates
+      let loginData = {
+        origin: login.origin,
+        formActionOrigin: login.formActionOrigin,
+        httpRealm: login.httpRealm,
+      };
+      const existingLogins = await Services.logins.searchLoginsAsync(loginData);
+
+      const matchingLogin = existingLogins.find(l => login.matches(l, true));
+      if (matchingLogin) {
+        if (continueOnDuplicates) {
+          continue;
+        } else {
+          throw lazy.LoginHelper.createLoginAlreadyExistsError(
+            matchingLogin.guid
+          );
+        }
+      }
+
+      const resultLogin = this.#addLogin(encryptedLogin);
+
+      // restore unencrypted username and password for use in `addLogin` event
+      // and return value
+      resultLogin.username = login.username;
+      resultLogin.password = login.password;
+
+      // Send a notification that a login was added.
+      lazy.LoginHelper.notifyStorageChanged("addLogin", resultLogin);
+
+      resultLogins.push(resultLogin);
+    }
+
+    return resultLogins;
+  }
+
+  removeLogin(login, fromSync) {
+    this._store.ensureDataReady();
+
+    let [idToDelete, storedLogin] = this._getIdForLogin(login);
+    if (!idToDelete) {
+      throw new Error("No matching logins");
+    }
+
+    let foundIndex = this._store.data.logins.findIndex(l => l.id == idToDelete);
+    if (foundIndex != -1) {
+      let login = this._store.data.logins[foundIndex];
+      if (!login.deleted) {
+        if (fromSync) {
+          this.#replaceLoginWithTombstone(login);
+        } else if (login.everSynced) {
+          // The login has been synced, so mark it as deleted.
+          this.#incrementSyncCounter(login);
+          this.#replaceLoginWithTombstone(login);
+        } else {
+          // The login was never synced, so just remove it from the data.
+          this._store.data.logins.splice(foundIndex, 1);
+        }
+
+        this._store.saveSoon();
+      }
+    }
+
+    lazy.LoginHelper.notifyStorageChanged("removeLogin", storedLogin);
+  }
+
+  modifyLogin(oldLogin, newLoginData, fromSync) {
+    this._store.ensureDataReady();
+
+    let [idToModify, oldStoredLogin] = this._getIdForLogin(oldLogin);
+    if (!idToModify) {
+      throw new Error("No matching logins");
+    }
+
+    let newLogin = lazy.LoginHelper.buildModifiedLogin(
+      oldStoredLogin,
+      newLoginData
+    );
+
+    // Check if the new GUID is duplicate.
+    if (
+      newLogin.guid != oldStoredLogin.guid &&
+      !this._isGuidUnique(newLogin.guid)
+    ) {
+      throw new Error("specified GUID already exists");
+    }
+
+    // Look for an existing entry in case key properties changed.
+    if (!newLogin.matches(oldLogin, true)) {
+      let loginData = {
+        origin: newLogin.origin,
+        formActionOrigin: newLogin.formActionOrigin,
+        httpRealm: newLogin.httpRealm,
+      };
+
+      let logins = this.searchLogins(
+        lazy.LoginHelper.newPropertyBag(loginData)
+      );
+
+      let matchingLogin = logins.find(login => newLogin.matches(login, true));
+      if (matchingLogin) {
+        throw lazy.LoginHelper.createLoginAlreadyExistsError(
+          matchingLogin.guid
+        );
+      }
+    }
+
+    // Don't sync changes to the accounts password or when changes were only
+    // made to fields that should not be synced.
+    if (
+      !fromSync &&
+      !isFXAHost(newLogin) &&
+      isSyncableChange(oldLogin, newLogin)
+    ) {
+      this.#incrementSyncCounter(newLogin);
+    }
+
+    // Get the encrypted value of the username and password.
+    let [encUsername, encPassword, encType, encUnknownFields] =
+      this._encryptLogin(newLogin);
+
+    for (let loginItem of this._store.data.logins) {
+      if (loginItem.id == idToModify && !loginItem.deleted) {
+        loginItem.hostname = newLogin.origin;
+        loginItem.httpRealm = newLogin.httpRealm;
+        loginItem.formSubmitURL = newLogin.formActionOrigin;
+        loginItem.usernameField = newLogin.usernameField;
+        loginItem.passwordField = newLogin.passwordField;
+        loginItem.encryptedUsername = encUsername;
+        loginItem.encryptedPassword = encPassword;
+        loginItem.guid = newLogin.guid;
+        loginItem.encType = encType;
+        loginItem.timeCreated = newLogin.timeCreated;
+        loginItem.timeLastUsed = newLogin.timeLastUsed;
+        loginItem.timePasswordChanged = newLogin.timePasswordChanged;
+        loginItem.timesUsed = newLogin.timesUsed;
+        loginItem.encryptedUnknownFields = encUnknownFields;
+        loginItem.syncCounter = newLogin.syncCounter;
+        this._store.saveSoon();
+        break;
+      }
+    }
+
+    lazy.LoginHelper.notifyStorageChanged("modifyLogin", [
+      oldStoredLogin,
+      newLogin,
+    ]);
+  }
+
+  // Replace the login with a tombstone. It has a guid and sync-related properties,
+  // but does not contain the login or password information.
+  #replaceLoginWithTombstone(login) {
+    login.deleted = true;
+
+    // Delete all fields except guid, timePasswordChanged, syncCounter
+    // and everSynced;
+    delete login.hostname;
+    delete login.httpRealm;
+    delete login.formSubmitURL;
+    delete login.usernameField;
+    delete login.passwordField;
+    delete login.encryptedUsername;
+    delete login.encryptedPassword;
+    delete login.encType;
+    delete login.timeCreated;
+    delete login.timeLastUsed;
+    delete login.timesUsed;
+    delete login.encryptedUnknownFields;
+  }
+
+  recordPasswordUse(login) {
+    // Update the lastUsed timestamp and increment the use count.
+    let propBag = Cc["@mozilla.org/hash-property-bag;1"].createInstance(
+      Ci.nsIWritablePropertyBag
+    );
+    propBag.setProperty("timeLastUsed", Date.now());
+    propBag.setProperty("timesUsedIncrement", 1);
+    this.modifyLogin(login, propBag);
+  }
+
+  async recordBreachAlertDismissal(loginGUID) {
+    this._store.ensureDataReady();
+    const dismissedBreachAlertsByLoginGUID =
+      this._store._data.dismissedBreachAlertsByLoginGUID;
+
+    dismissedBreachAlertsByLoginGUID[loginGUID] = {
+      timeBreachAlertDismissed: new Date().getTime(),
+    };
+
+    return this._store.saveSoon();
+  }
+
+  getBreachAlertDismissalsByLoginGUID() {
+    this._store.ensureDataReady();
+    return this._store._data.dismissedBreachAlertsByLoginGUID;
+  }
+
+  /**
+   * Returns an array of nsILoginInfo. If decryption of a login
+   * fails due to a corrupt entry, the login is not included in
+   * the resulting array.
+   *
+   * @resolve {nsILoginInfo[]}
+   */
+  async getAllLogins(includeDeleted) {
+    this._store.ensureDataReady();
+
+    let [logins] = this._searchLogins({}, includeDeleted);
+    if (!logins.length) {
+      return [];
+    }
+
+    return this.#decryptLogins(logins);
+  }
+
+  async searchLoginsAsync(matchData, includeDeleted) {
+    this.log(`Searching for matching logins for origin ${matchData.origin}.`);
+    let result = this.searchLogins(
+      lazy.LoginHelper.newPropertyBag(matchData),
+      includeDeleted
+    );
+    // Emulate being async:
+    return Promise.resolve(result);
+  }
+
+  /**
+   * Public wrapper around _searchLogins to convert the nsIPropertyBag to a
+   * JavaScript object and decrypt the results.
+   *
+   * @return {nsILoginInfo[]} which are decrypted.
+   */
+  searchLogins(matchData, includeDeleted) {
+    this._store.ensureDataReady();
+
+    let realMatchData = {};
+    let options = {};
+
+    matchData.QueryInterface(Ci.nsIPropertyBag2);
+    if (matchData.hasKey("guid")) {
+      // Enforce GUID-based filtering when available, since the origin of the
+      // login may not match the origin of the form in the case of scheme
+      // upgrades.
+      realMatchData = { guid: matchData.getProperty("guid") };
+    } else {
+      // Convert nsIPropertyBag to normal JS object.
+      for (let prop of matchData.enumerator) {
+        switch (prop.name) {
+          // Some property names aren't field names but are special options to
+          // affect the search.
+          case "acceptDifferentSubdomains":
+          case "schemeUpgrades":
+          case "acceptRelatedRealms":
+          case "relatedRealms": {
+            options[prop.name] = prop.value;
+            break;
+          }
+          default: {
+            realMatchData[prop.name] = prop.value;
+            break;
+          }
+        }
+      }
+    }
+
+    let [logins] = this._searchLogins(realMatchData, includeDeleted, options);
+
+    // Decrypt entries found for the caller.
+    logins = this._decryptLogins(logins);
+
+    return logins;
+  }
+
+  /**
+   * Private method to perform arbitrary searches on any field. Decryption is
+   * left to the caller.
+   *
+   * formActionOrigin is handled specially for compatibility. If a null string
+   * is passed and other match fields are present, it is treated as if it was
+   * not present.
+   *
+   * Returns [logins, ids] for logins that match the arguments, where logins
+   * is an array of encrypted nsLoginInfo and ids is an array of associated
+   * ids in the database.
+   */
+  _searchLogins(
+    matchData,
+    includeDeleted = false,
+    aOptions = {
+      schemeUpgrades: false,
+      acceptDifferentSubdomains: false,
+      acceptRelatedRealms: false,
+      relatedRealms: [],
+    },
+    candidateLogins = this._store.data.logins
+  ) {
+    function match(aLoginItem) {
+      for (let field in matchData) {
+        let wantedValue = matchData[field];
+
+        // Override the storage field name for some fields due to backwards
+        // compatibility with Sync/storage.
+        let storageFieldName = field;
+        switch (field) {
+          case "formActionOrigin": {
+            storageFieldName = "formSubmitURL";
+            break;
+          }
+          case "origin": {
+            storageFieldName = "hostname";
+            break;
+          }
+        }
+
+        switch (field) {
+          case "formActionOrigin":
+            if (wantedValue != null) {
+              // Historical compatibility requires this special case
+              if (
+                aLoginItem.formSubmitURL == "" ||
+                (wantedValue == "" && Object.keys(matchData).length != 1)
+              ) {
+                break;
+              }
+              if (
+                !lazy.LoginHelper.isOriginMatching(
+                  aLoginItem[storageFieldName],
+                  wantedValue,
+                  aOptions
+                )
+              ) {
+                return false;
+              }
+              break;
+            }
+          // fall through
+          case "origin":
+            if (wantedValue != null) {
+              // needed for formActionOrigin fall through
+              if (
+                !lazy.LoginHelper.isOriginMatching(
+                  aLoginItem[storageFieldName],
+                  wantedValue,
+                  aOptions
+                )
+              ) {
+                return false;
+              }
+              break;
+            }
+          // Normal cases.
+          // fall through
+          case "httpRealm":
+          case "id":
+          case "usernameField":
+          case "passwordField":
+          case "encryptedUsername":
+          case "encryptedPassword":
+          case "guid":
+          case "encType":
+          case "timeCreated":
+          case "timeLastUsed":
+          case "timePasswordChanged":
+          case "timesUsed":
+          case "syncCounter":
+          case "everSynced":
+            if (wantedValue == null && aLoginItem[storageFieldName]) {
+              return false;
+            } else if (aLoginItem[storageFieldName] != wantedValue) {
+              return false;
+            }
+            break;
+          // Fail if caller requests an unknown property.
+          default:
+            throw new Error("Unexpected field: " + field);
+        }
+      }
+      return true;
+    }
+
+    let foundLogins = [],
+      foundIds = [];
+    for (let loginItem of candidateLogins) {
+      if (loginItem.deleted && !includeDeleted) {
+        continue; // skip deleted items
+      }
+
+      if (match(loginItem)) {
+        // Create the new nsLoginInfo object, push to array
+        let login = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(
+          Ci.nsILoginInfo
+        );
+        login.init(
+          loginItem.hostname,
+          loginItem.formSubmitURL,
+          loginItem.httpRealm,
+          loginItem.encryptedUsername,
+          loginItem.encryptedPassword,
+          loginItem.usernameField,
+          loginItem.passwordField
+        );
+        // set nsILoginMetaInfo values
+        login.QueryInterface(Ci.nsILoginMetaInfo);
+        login.guid = loginItem.guid;
+        login.timeCreated = loginItem.timeCreated;
+        login.timeLastUsed = loginItem.timeLastUsed;
+        login.timePasswordChanged = loginItem.timePasswordChanged;
+        login.timesUsed = loginItem.timesUsed;
+        login.syncCounter = loginItem.syncCounter;
+        login.everSynced = loginItem.everSynced;
+
+        // Any unknown fields along for the ride
+        login.unknownFields = loginItem.encryptedUnknownFields;
+        foundLogins.push(login);
+        foundIds.push(loginItem.id);
+      }
+    }
+
+    this.log(
+      `Returning ${foundLogins.length} logins for specified origin with options ${aOptions}`
+    );
+    return [foundLogins, foundIds];
+  }
+
+  /**
+   * Removes all logins from local storage, including FxA Sync key.
+   *
+   * NOTE: You probably want removeAllUserFacingLogins instead of this function.
+   *
+   */
+  removeAllLogins() {
+    this.#removeLogins(false, true);
+  }
+
+  /**
+   * Removes all user facing logins from storage. e.g. all logins except the FxA Sync key
+   *
+   * If you need to remove the FxA key, use `removeAllLogins` instead
+   *
+   * @param fullyRemove remove the logins rather than mark them deleted.
+   */
+  removeAllUserFacingLogins(fullyRemove) {
+    this.#removeLogins(fullyRemove, false);
+  }
+
+  /**
+   * Removes all logins from storage. If removeFXALogin is true, then the FxA Sync
+   * key is also removed.
+   *
+   * @param fullyRemove remove the logins rather than mark them deleted.
+   * @param removeFXALogin also remove the FxA Sync key.
+   */
+  #removeLogins(fullyRemove, removeFXALogin = false) {
+    this._store.ensureDataReady();
+    this.log("Removing all logins.");
+
+    let removedLogins = [];
+    let remainingLogins = [];
+    for (let login of this._store.data.logins) {
+      if (
+        !removeFXALogin &&
+        isFXAHost(login) &&
+        login.httpRealm == lazy.FXA_PWDMGR_REALM
+      ) {
+        remainingLogins.push(login);
+      } else {
+        removedLogins.push(login);
+        if (!fullyRemove && login?.everSynced) {
+          // The login has been synced, so mark it as deleted.
+          this.#incrementSyncCounter(login);
+          this.#replaceLoginWithTombstone(login);
+          remainingLogins.push(login);
+        }
+      }
+    }
+    this._store.data.logins = remainingLogins;
+
+    this._store.data.potentiallyVulnerablePasswords = [];
+    this.__decryptedPotentiallyVulnerablePasswords = null;
+    this._store.data.dismissedBreachAlertsByLoginGUID = {};
+    this._store.saveSoon();
+
+    lazy.LoginHelper.notifyStorageChanged("removeAllLogins", removedLogins);
+  }
+
+  findLogins(origin, formActionOrigin, httpRealm) {
+    this._store.ensureDataReady();
+
+    let loginData = {
+      origin,
+      formActionOrigin,
+      httpRealm,
+    };
+    let matchData = {};
+    for (let field of ["origin", "formActionOrigin", "httpRealm"]) {
+      if (loginData[field] != "") {
+        matchData[field] = loginData[field];
+      }
+    }
+    let [logins] = this._searchLogins(matchData);
+
+    // Decrypt entries found for the caller.
+    logins = this._decryptLogins(logins);
+
+    this.log(`Returning ${logins.length} logins.`);
+    return logins;
+  }
+
+  countLogins(origin, formActionOrigin, httpRealm) {
+    this._store.ensureDataReady();
+
+    let loginData = {
+      origin,
+      formActionOrigin,
+      httpRealm,
+    };
+    let matchData = {};
+    for (let field of ["origin", "formActionOrigin", "httpRealm"]) {
+      if (loginData[field] != "") {
+        matchData[field] = loginData[field];
+      }
+    }
+    let [logins] = this._searchLogins(matchData);
+
+    this.log(`Counted ${logins.length} logins.`);
+    return logins.length;
+  }
+
+  addPotentiallyVulnerablePassword(login) {
+    this._store.ensureDataReady();
+    // this breached password is already stored
+    if (this.isPotentiallyVulnerablePassword(login)) {
+      return;
+    }
+    this.__decryptedPotentiallyVulnerablePasswords.push(login.password);
+
+    this._store.data.potentiallyVulnerablePasswords.push({
+      encryptedPassword: this._crypto.encrypt(login.password),
+    });
+    this._store.saveSoon();
+  }
+
+  isPotentiallyVulnerablePassword(login) {
+    return this._decryptedPotentiallyVulnerablePasswords.includes(
+      login.password
+    );
+  }
+
+  clearAllPotentiallyVulnerablePasswords() {
+    this._store.ensureDataReady();
+    if (!this._store.data.potentiallyVulnerablePasswords.length) {
+      // No need to write to disk
+      return;
+    }
+    this._store.data.potentiallyVulnerablePasswords = [];
+    this._store.saveSoon();
+    this.__decryptedPotentiallyVulnerablePasswords = null;
+  }
+
+  get uiBusy() {
+    return this._crypto.uiBusy;
+  }
+
+  get isLoggedIn() {
+    return this._crypto.isLoggedIn;
+  }
+
+  /**
+   * Returns an array with two items: [id, login]. If the login was not
+   * found, both items will be null. The returned login contains the actual
+   * stored login (useful for looking at the actual nsILoginMetaInfo values).
+   */
+  _getIdForLogin(login) {
+    this._store.ensureDataReady();
+
+    let matchData = {};
+    for (let field of ["origin", "formActionOrigin", "httpRealm"]) {
+      if (login[field] != "") {
+        matchData[field] = login[field];
+      }
+    }
+    let [logins, ids] = this._searchLogins(matchData);
+
+    let id = null;
+    let foundLogin = null;
+
+    // The specified login isn't encrypted, so we need to ensure
+    // the logins we're comparing with are decrypted. We decrypt one entry
+    // at a time, lest _decryptLogins return fewer entries and screw up
+    // indices between the two.
+    for (let i = 0; i < logins.length; i++) {
+      let [decryptedLogin] = this._decryptLogins([logins[i]]);
+
+      if (!decryptedLogin || !decryptedLogin.equals(login)) {
+        continue;
+      }
+
+      // We've found a match, set id and break
+      foundLogin = decryptedLogin;
+      id = ids[i];
+      break;
+    }
+
+    return [id, foundLogin];
+  }
+
+  /**
+   * Checks to see if the specified GUID already exists.
+   */
+  _isGuidUnique(guid) {
+    this._store.ensureDataReady();
+
+    return this._store.data.logins.every(l => l.guid != guid);
+  }
+
+  /*
+   * Asynchronously encrypt multiple logins.
+   * Returns a promise resolving to an array of arrays containing two entries:
+   * the original login and a clone with encrypted properties.
+   */
+  async #encryptLogins(logins) {
+    if (logins.length === 0) {
+      return logins;
+    }
+
+    const plaintexts = logins.reduce(
+      (memo, { username, password, unknownFields }) =>
+        memo.concat([username, password, unknownFields]),
+      []
+    );
+    const ciphertexts = await this._crypto.encryptMany(plaintexts);
+
+    return logins.map((login, i) => {
+      const [encryptedUsername, encryptedPassword, encryptedUnknownFields] =
+        ciphertexts.slice(3 * i, 3 * i + 3);
+
+      const encryptedLogin = login.clone();
+      encryptedLogin.username = encryptedUsername;
+      encryptedLogin.password = encryptedPassword;
+      encryptedLogin.unknownFields = encryptedUnknownFields;
+
+      return [login, encryptedLogin];
+    });
+  }
+
+  /*
+   * Asynchronously decrypt multiple logins.
+   * Returns a promise resolving to an array of clones with decrypted properties.
+   */
+  async #decryptLogins(logins) {
+    if (logins.length === 0) {
+      return logins;
+    }
+
+    const ciphertexts = logins.reduce(
+      (memo, { username, password, unknownFields }) =>
+        memo.concat([username, password, unknownFields]),
+      []
+    );
+    const plaintexts = await this._crypto.decryptMany(ciphertexts);
+
+    return logins
+      .map((login, i) => {
+        // Deleted logins don't have any info to decrypt.
+        const decryptedLogin = login.clone();
+        if (this.loginIsDeleted(login.guid)) {
+          return decryptedLogin;
+        }
+
+        const [username, password, unknownFields] = plaintexts.slice(
+          3 * i,
+          3 * i + 3
+        );
+
+        // If the username or password is blank it means that decryption may have
+        // failed during decryptMany but we can't differentiate an empty string
+        // value from a failure so we attempt to decrypt again and check the
+        // result.
+        if (!username || !password) {
+          try {
+            this._crypto.decrypt(login.username);
+            this._crypto.decrypt(login.password);
+          } catch (e) {
+            // If decryption failed (corrupt entry?), just return it as it is.
+            // Rethrow other errors (like canceling entry of a primary pw)
+            if (e.result == Cr.NS_ERROR_FAILURE) {
+              this.log(
+                `Could not decrypt login: ${
+                  login.QueryInterface(Ci.nsILoginMetaInfo).guid
+                }.`
+              );
+              return null;
+            }
+            throw e;
+          }
+        }
+
+        decryptedLogin.username = username;
+        decryptedLogin.password = password;
+        decryptedLogin.unknownFields = unknownFields;
+
+        return decryptedLogin;
+      })
+      .filter(Boolean);
+  }
+
+  /**
+   * Returns the encrypted username, password, and encrypton type for the specified
+   * login. Can throw if the user cancels a primary password entry.
+   */
+  _encryptLogin(login) {
+    let encUsername = this._crypto.encrypt(login.username);
+    let encPassword = this._crypto.encrypt(login.password);
+
+    // Unknown fields should be encrypted since we can't know whether new fields
+    // from other clients will contain sensitive data or not
+    let encUnknownFields = null;
+    if (login.unknownFields) {
+      encUnknownFields = this._crypto.encrypt(login.unknownFields);
+    }
+    let encType = this._crypto.defaultEncType;
+
+    return [encUsername, encPassword, encType, encUnknownFields];
+  }
+
+  /**
+   * Decrypts username and password fields in the provided array of
+   * logins.
+   *
+   * The entries specified by the array will be decrypted, if possible.
+   * An array of successfully decrypted logins will be returned. The return
+   * value should be given to external callers (since still-encrypted
+   * entries are useless), whereas internal callers generally don't want
+   * to lose unencrypted entries (eg, because the user clicked Cancel
+   * instead of entering their primary password)
+   */
+  _decryptLogins(logins) {
+    let result = [];
+
+    for (let login of logins) {
+      if (this.loginIsDeleted(login.guid)) {
+        result.push(login);
+        continue;
+      }
+
+      try {
+        login.username = this._crypto.decrypt(login.username);
+        login.password = this._crypto.decrypt(login.password);
+        // Verify unknownFields actually has a value
+        if (login.unknownFields) {
+          login.unknownFields = this._crypto.decrypt(login.unknownFields);
+        }
+      } catch (e) {
+        // If decryption failed (corrupt entry?), just skip it.
+        // Rethrow other errors (like canceling entry of a primary pw)
+        if (e.result == Cr.NS_ERROR_FAILURE) {
+          continue;
+        }
+        throw e;
+      }
+      result.push(login);
+    }
+
+    return result;
+  }
+}
+
+ChromeUtils.defineLazyGetter(LoginManagerStorage_json.prototype, "log", () => {
+  let logger = lazy.LoginHelper.createLogger("Login storage");
+  return logger.log.bind(logger);
+});
diff --git a/toolkit/components/passwordmgr/test/LoginTestUtils.sys.mjs b/toolkit/components/passwordmgr/test/LoginTestUtils.sys.mjs
new file mode 100644
index 0000000000..94e48aac6a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/LoginTestUtils.sys.mjs
@@ -0,0 +1,662 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Shared functions generally available for testing login components.
+ */
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  RemoteSettings: "resource://services-settings/remote-settings.sys.mjs",
+});
+
+import { Assert as AssertCls } from "resource://testing-common/Assert.sys.mjs";
+
+let Assert = AssertCls;
+
+import { TestUtils } from "resource://testing-common/TestUtils.sys.mjs";
+import { setTimeout } from "resource://gre/modules/Timer.sys.mjs";
+import { FileTestUtils } from "resource://testing-common/FileTestUtils.sys.mjs";
+
+const LoginInfo = Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  "nsILoginInfo",
+  "init"
+);
+
+export const LoginTestUtils = {
+  setAssertReporter(reporterFunc) {
+    Assert = new AssertCls(Cu.waiveXrays(reporterFunc));
+  },
+
+  /**
+   * Forces the storage module to save all data, and the Login Manager service
+   * to replace the storage module with a newly initialized instance.
+   */
+  async reloadData() {
+    Services.obs.notifyObservers(null, "passwordmgr-storage-replace");
+    await TestUtils.topicObserved("passwordmgr-storage-replace-complete");
+  },
+
+  /**
+   * Erases all the data stored by the Login Manager service.
+   */
+  clearData() {
+    Services.logins.removeAllUserFacingLogins();
+    for (let origin of Services.logins.getAllDisabledHosts()) {
+      Services.logins.setLoginSavingEnabled(origin, true);
+    }
+  },
+
+  /**
+   * Add a new login to the store
+   */
+  async addLogin({
+    username,
+    password,
+    origin = "https://example.com",
+    formActionOrigin,
+  }) {
+    const login = LoginTestUtils.testData.formLogin({
+      origin,
+      formActionOrigin: formActionOrigin || origin,
+      username,
+      password,
+    });
+    return Services.logins.addLoginAsync(login);
+  },
+
+  async modifyLogin(oldLogin, newLogin) {
+    const storageChangedPromise = TestUtils.topicObserved(
+      "passwordmgr-storage-changed",
+      (_, data) => data == "modifyLogin"
+    );
+    Services.logins.modifyLogin(oldLogin, newLogin);
+    await storageChangedPromise;
+  },
+
+  resetGeneratedPasswordsCache() {
+    let { LoginManagerParent } = ChromeUtils.importESModule(
+      "resource://gre/modules/LoginManagerParent.sys.mjs"
+    );
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+  },
+
+  /**
+   * Checks that the currently stored list of nsILoginInfo matches the provided
+   * array.  If no `checkFn` is provided, the comparison uses the "equals"
+   * method of nsILoginInfo, that does not include nsILoginMetaInfo properties in the test.
+   */
+  async checkLogins(expectedLogins, msg = "checkLogins", checkFn = undefined) {
+    this.assertLoginListsEqual(
+      await Services.logins.getAllLogins(),
+      expectedLogins,
+      msg,
+      checkFn
+    );
+  },
+
+  /**
+   * Checks that the two provided arrays of nsILoginInfo have the same length,
+   * and every login in "expected" is also found in "actual".  If no `checkFn`
+   * is provided, the comparison uses the "equals" method of nsILoginInfo, that
+   * does not include nsILoginMetaInfo properties in the test.
+   */
+  assertLoginListsEqual(
+    actual,
+    expected,
+    msg = "assertLoginListsEqual",
+    checkFn = undefined
+  ) {
+    Assert.equal(expected.length, actual.length, msg);
+    Assert.ok(
+      expected.every(e =>
+        actual.some(a => {
+          return checkFn ? checkFn(a, e) : a.equals(e);
+        })
+      ),
+      msg
+    );
+  },
+
+  /**
+   * Checks that the two provided arrays of strings contain the same values,
+   * maybe in a different order, case-sensitively.
+   */
+  assertDisabledHostsEqual(actual, expected) {
+    Assert.deepEqual(actual.sort(), expected.sort());
+  },
+
+  /**
+   * Checks whether the given time, expressed as the number of milliseconds
+   * since January 1, 1970, 00:00:00 UTC, falls within 30 seconds of now.
+   */
+  assertTimeIsAboutNow(timeMs) {
+    Assert.ok(Math.abs(timeMs - Date.now()) < 30000);
+  },
+};
+
+/**
+ * This object contains functions that return new instances of nsILoginInfo for
+ * every call.  The returned instances can be compared using their "equals" or
+ * "matches" methods, or modified for the needs of the specific test being run.
+ *
+ * Any modification to the test data requires updating the tests accordingly, in
+ * particular the search tests.
+ */
+LoginTestUtils.testData = {
+  /**
+   * Returns a new nsILoginInfo for use with form submits.
+   *
+   * @param modifications
+   *        Each property of this object replaces the property of the same name
+   *        in the returned nsILoginInfo or nsILoginMetaInfo.
+   */
+  formLogin(modifications) {
+    let loginInfo = new LoginInfo(
+      "http://www3.example.com",
+      "http://www.example.com",
+      null,
+      "the username",
+      "the password",
+      "form_field_username",
+      "form_field_password"
+    );
+    loginInfo.QueryInterface(Ci.nsILoginMetaInfo);
+    if (modifications) {
+      for (let [name, value] of Object.entries(modifications)) {
+        if (name == "httpRealm" && value !== null) {
+          throw new Error("httpRealm not supported for form logins");
+        }
+        loginInfo[name] = value;
+      }
+    }
+    return loginInfo;
+  },
+
+  /**
+   * Returns a new nsILoginInfo for use with HTTP authentication.
+   *
+   * @param modifications
+   *        Each property of this object replaces the property of the same name
+   *        in the returned nsILoginInfo or nsILoginMetaInfo.
+   */
+  authLogin(modifications) {
+    let loginInfo = new LoginInfo(
+      "http://www.example.org",
+      null,
+      "The HTTP Realm",
+      "the username",
+      "the password"
+    );
+    loginInfo.QueryInterface(Ci.nsILoginMetaInfo);
+    if (modifications) {
+      for (let [name, value] of Object.entries(modifications)) {
+        if (name == "formActionOrigin" && value !== null) {
+          throw new Error(
+            "formActionOrigin not supported for HTTP auth. logins"
+          );
+        }
+        loginInfo[name] = value;
+      }
+    }
+    return loginInfo;
+  },
+
+  /**
+   * Returns an array of typical nsILoginInfo that could be stored in the
+   * database.
+   */
+  loginList() {
+    return [
+      // --- Examples of form logins (subdomains of example.com) ---
+
+      // Simple form login with named fields for username and password.
+      new LoginInfo(
+        "http://www.example.com",
+        "http://www.example.com",
+        null,
+        "the username",
+        "the password for www.example.com",
+        "form_field_username",
+        "form_field_password"
+      ),
+
+      // Different schemes are treated as completely different sites.
+      new LoginInfo(
+        "https://www.example.com",
+        "https://www.example.com",
+        null,
+        "the username",
+        "the password for https",
+        "form_field_username",
+        "form_field_password"
+      ),
+
+      // Subdomains can be treated as completely different sites depending on the UI invoked.
+      new LoginInfo(
+        "https://example.com",
+        "https://example.com",
+        null,
+        "the username",
+        "the password for example.com",
+        "form_field_username",
+        "form_field_password"
+      ),
+
+      // Forms found on the same origin, but with different origins in the
+      // "action" attribute, are handled independently.
+      new LoginInfo(
+        "http://www3.example.com",
+        "http://www.example.com",
+        null,
+        "the username",
+        "the password",
+        "form_field_username",
+        "form_field_password"
+      ),
+      new LoginInfo(
+        "http://www3.example.com",
+        "https://www.example.com",
+        null,
+        "the username",
+        "the password",
+        "form_field_username",
+        "form_field_password"
+      ),
+      new LoginInfo(
+        "http://www3.example.com",
+        "http://example.com",
+        null,
+        "the username",
+        "the password",
+        "form_field_username",
+        "form_field_password"
+      ),
+
+      // It is not possible to store multiple passwords for the same username,
+      // however multiple passwords can be stored when the usernames differ.
+      // An empty username is a valid case and different from the others.
+      new LoginInfo(
+        "http://www4.example.com",
+        "http://www4.example.com",
+        null,
+        "username one",
+        "password one",
+        "form_field_username",
+        "form_field_password"
+      ),
+      new LoginInfo(
+        "http://www4.example.com",
+        "http://www4.example.com",
+        null,
+        "username two",
+        "password two",
+        "form_field_username",
+        "form_field_password"
+      ),
+      new LoginInfo(
+        "http://www4.example.com",
+        "http://www4.example.com",
+        null,
+        "",
+        "password three",
+        "form_field_username",
+        "form_field_password"
+      ),
+
+      // Username and passwords fields in forms may have no "name" attribute.
+      new LoginInfo(
+        "http://www5.example.com",
+        "http://www5.example.com",
+        null,
+        "multi username",
+        "multi password",
+        "",
+        ""
+      ),
+
+      // Forms with PIN-type authentication will typically have no username.
+      new LoginInfo(
+        "http://www6.example.com",
+        "http://www6.example.com",
+        null,
+        "",
+        "12345",
+        "",
+        "form_field_password"
+      ),
+
+      // Logins can be saved on non-default ports
+      new LoginInfo(
+        "https://www7.example.com:8080",
+        "https://www7.example.com:8080",
+        null,
+        "8080_username",
+        "8080_pass"
+      ),
+
+      new LoginInfo(
+        "https://www7.example.com:8080",
+        null,
+        "My dev server",
+        "8080_username2",
+        "8080_pass2"
+      ),
+
+      // --- Examples of authentication logins (subdomains of example.org) ---
+
+      // Simple HTTP authentication login.
+      new LoginInfo(
+        "http://www.example.org",
+        null,
+        "The HTTP Realm",
+        "the username",
+        "the password"
+      ),
+
+      // Simple FTP authentication login.
+      new LoginInfo(
+        "ftp://ftp.example.org",
+        null,
+        "ftp://ftp.example.org",
+        "the username",
+        "the password"
+      ),
+
+      // Multiple HTTP authentication logins can be stored for different realms.
+      new LoginInfo(
+        "http://www2.example.org",
+        null,
+        "The HTTP Realm",
+        "the username",
+        "the password"
+      ),
+      new LoginInfo(
+        "http://www2.example.org",
+        null,
+        "The HTTP Realm Other",
+        "the username other",
+        "the password other"
+      ),
+
+      // --- Both form and authentication logins (example.net) ---
+
+      new LoginInfo(
+        "http://example.net",
+        "http://example.net",
+        null,
+        "the username",
+        "the password",
+        "form_field_username",
+        "form_field_password"
+      ),
+      new LoginInfo(
+        "http://example.net",
+        "http://www.example.net",
+        null,
+        "the username",
+        "the password",
+        "form_field_username",
+        "form_field_password"
+      ),
+      new LoginInfo(
+        "http://example.net",
+        "http://www.example.net",
+        null,
+        "username two",
+        "the password",
+        "form_field_username",
+        "form_field_password"
+      ),
+      new LoginInfo(
+        "http://example.net",
+        null,
+        "The HTTP Realm",
+        "the username",
+        "the password"
+      ),
+      new LoginInfo(
+        "http://example.net",
+        null,
+        "The HTTP Realm Other",
+        "username two",
+        "the password"
+      ),
+      new LoginInfo(
+        "ftp://example.net",
+        null,
+        "ftp://example.net",
+        "the username",
+        "the password"
+      ),
+      // null formActionOrigin, empty httpRealm
+      new LoginInfo(
+        "http://example.net",
+        null,
+        "",
+        "the username",
+        "the password"
+      ),
+
+      // --- Examples of logins added by extensions (chrome scheme) ---
+
+      new LoginInfo(
+        "chrome://example_extension",
+        null,
+        "Example Login One",
+        "the username",
+        "the password one",
+        "",
+        ""
+      ),
+      new LoginInfo(
+        "chrome://example_extension",
+        null,
+        "Example Login Two",
+        "the username",
+        "the password two"
+      ),
+
+      // -- file:// URIs throw accessing nsIURI.host
+
+      new LoginInfo(
+        "file://",
+        "file://",
+        null,
+        "file: username",
+        "file: password"
+      ),
+
+      // -- javascript: URIs throw accessing nsIURI.host.
+      // They should only be used for the formActionOrigin.
+      new LoginInfo(
+        "https://js.example.com",
+        "javascript:",
+        null,
+        "javascript: username",
+        "javascript: password"
+      ),
+    ];
+  },
+};
+
+LoginTestUtils.recipes = {
+  getRecipeParent() {
+    let { LoginManagerParent } = ChromeUtils.importESModule(
+      "resource://gre/modules/LoginManagerParent.sys.mjs"
+    );
+    if (!LoginManagerParent.recipeParentPromise) {
+      return null;
+    }
+    return LoginManagerParent.recipeParentPromise.then(recipeParent => {
+      return recipeParent;
+    });
+  },
+};
+
+LoginTestUtils.primaryPassword = {
+  primaryPassword: "omgsecret!",
+
+  _set(enable, stayLoggedIn) {
+    let oldPW, newPW;
+    if (enable) {
+      oldPW = "";
+      newPW = this.primaryPassword;
+    } else {
+      oldPW = this.primaryPassword;
+      newPW = "";
+    }
+    try {
+      let pk11db = Cc["@mozilla.org/security/pk11tokendb;1"].getService(
+        Ci.nsIPK11TokenDB
+      );
+      let token = pk11db.getInternalKeyToken();
+      if (token.needsUserInit) {
+        dump("MP initialized to " + newPW + "\n");
+        token.initPassword(newPW);
+      } else {
+        token.checkPassword(oldPW);
+        dump("MP change from " + oldPW + " to " + newPW + "\n");
+        token.changePassword(oldPW, newPW);
+        if (!stayLoggedIn) {
+          token.logoutSimple();
+        }
+      }
+    } catch (e) {
+      dump(
+        "Tried to enable an already enabled primary password or disable an already disabled primary password!"
+      );
+    }
+  },
+
+  enable(stayLoggedIn = false) {
+    this._set(true, stayLoggedIn);
+  },
+
+  disable() {
+    this._set(false);
+  },
+};
+
+/**
+ * Utilities related to interacting with login fields in content.
+ */
+LoginTestUtils.loginField = {
+  checkPasswordMasked(field, expected, msg) {
+    let { editor } = field;
+    let valueLength = field.value.length;
+    Assert.equal(
+      editor.autoMaskingEnabled,
+      expected,
+      `Check autoMaskingEnabled: ${msg}`
+    );
+    Assert.equal(editor.unmaskedStart, 0, `unmaskedStart is 0: ${msg}`);
+    if (expected) {
+      Assert.equal(editor.unmaskedEnd, 0, `Password is masked: ${msg}`);
+    } else {
+      Assert.equal(
+        editor.unmaskedEnd,
+        valueLength,
+        `Unmasked to the end: ${msg}`
+      );
+    }
+  },
+};
+
+LoginTestUtils.generation = {
+  LENGTH: 15,
+  REGEX: /^[a-km-np-zA-HJ-NP-Z2-9-~!@#$%^&*_+=)}:;"'>,.?\]]{15}$/,
+};
+
+LoginTestUtils.telemetry = {
+  async waitForEventCount(
+    count,
+    process = "content",
+    category = "pwmgr",
+    method = undefined
+  ) {
+    // The test is already unreliable (see bug 1627419 and 1605494) and relied on
+    // the implicit 100ms initial timer of waitForCondition that bug 1596165 removed.
+    await new Promise(resolve => setTimeout(resolve, 100));
+    let events = await TestUtils.waitForCondition(() => {
+      let events = Services.telemetry.snapshotEvents(
+        Ci.nsITelemetry.DATASET_PRERELEASE_CHANNELS,
+        false
+      )[process];
+
+      if (!events) {
+        return null;
+      }
+
+      events = events.filter(
+        e => e[1] == category && (!method || e[2] == method)
+      );
+      dump(`Waiting for ${count} events, got ${events.length}\n`);
+      return events.length == count ? events : null;
+    }, "waiting for telemetry event count of: " + count);
+    Assert.equal(events.length, count, "waiting for telemetry event count");
+    return events;
+  },
+};
+
+LoginTestUtils.file = {
+  /**
+   * Given an array of strings it creates a temporary CSV file that has them as content.
+   *
+   * @param {string[]} csvLines
+   *        The lines that make up the CSV file.
+   * @param {string} extension
+   *        Optional parameter. Either 'csv' or 'tsv'. Default is 'csv'.
+   * @returns {window.File} The File to the CSV file that was created.
+   */
+  async setupCsvFileWithLines(csvLines, extension = "csv") {
+    let tmpFile = FileTestUtils.getTempFile(`firefox_logins.${extension}`);
+    await IOUtils.writeUTF8(tmpFile.path, csvLines.join("\r\n"));
+    return tmpFile;
+  },
+};
+
+LoginTestUtils.remoteSettings = {
+  relatedRealmsCollection: "websites-with-shared-credential-backends",
+  async setupWebsitesWithSharedCredentials(
+    relatedRealms = [["other-example.com", "example.com", "example.co.uk"]]
+  ) {
+    let db = lazy.RemoteSettings(this.relatedRealmsCollection).db;
+    await db.clear();
+    await db.create({
+      id: "some-fake-ID-abc",
+      relatedRealms,
+    });
+    await db.importChanges({}, Date.now());
+  },
+  async cleanWebsitesWithSharedCredentials() {
+    let db = lazy.RemoteSettings(this.relatedRealmsCollection).db;
+    await db.importChanges({}, Date.now(), [], { clear: true });
+  },
+  improvedPasswordRulesCollection: "password-rules",
+
+  async setupImprovedPasswordRules(
+    origin = "example.com",
+    rules = "minlength: 6; maxlength: 16; required: lower, upper; required: digit; required: [&<>'\"!#$%(),:;=?[^`{|}~]]; max-consecutive: 2;"
+  ) {
+    let db = lazy.RemoteSettings(this.improvedPasswordRulesCollection).db;
+    await db.clear();
+    await db.create({
+      id: "some-fake-ID",
+      Domain: origin,
+      "password-rules": rules,
+    });
+    await db.create({
+      id: "some-fake-ID-2",
+      Domain: origin,
+      "password-rules": rules,
+    });
+    await db.importChanges({}, Date.now());
+  },
+  async cleanImprovedPasswordRules() {
+    let db = lazy.RemoteSettings(this.improvedPasswordRulesCollection).db;
+    await db.importChanges({}, Date.now(), [], { clear: true });
+  },
+};
diff --git a/toolkit/components/passwordmgr/test/authenticate.sjs b/toolkit/components/passwordmgr/test/authenticate.sjs
new file mode 100644
index 0000000000..5d73dfef4c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/authenticate.sjs
@@ -0,0 +1,229 @@
+"use strict";
+
+function handleRequest(request, response) {
+  try {
+    reallyHandleRequest(request, response);
+  } catch (e) {
+    response.setStatusLine("1.0", 200, "AlmostOK");
+    response.write("Error handling request: " + e);
+  }
+}
+
+function reallyHandleRequest(request, response) {
+  let match;
+  let requestAuth = true,
+    requestProxyAuth = true;
+
+  // Allow the caller to drive how authentication is processed via the query.
+  // Eg, http://localhost:8888/authenticate.sjs?user=foo&realm=bar
+  // The extra ? allows the user/pass/realm checks to succeed if the name is
+  // at the beginning of the query string.
+  let query = "?" + request.queryString;
+
+  let expected_user = "",
+    expected_pass = "",
+    realm = "mochitest";
+  let proxy_expected_user = "",
+    proxy_expected_pass = "",
+    proxy_realm = "mochi-proxy";
+  let huge = false,
+    plugin = false,
+    anonymous = false,
+    formauth = false;
+  let authHeaderCount = 1;
+  // user=xxx
+  match = /[^_]user=([^&]*)/.exec(query);
+  if (match) {
+    expected_user = match[1];
+  }
+
+  // pass=xxx
+  match = /[^_]pass=([^&]*)/.exec(query);
+  if (match) {
+    expected_pass = match[1];
+  }
+
+  // realm=xxx
+  match = /[^_]realm=([^&]*)/.exec(query);
+  if (match) {
+    realm = match[1];
+  }
+
+  // proxy_user=xxx
+  match = /proxy_user=([^&]*)/.exec(query);
+  if (match) {
+    proxy_expected_user = match[1];
+  }
+
+  // proxy_pass=xxx
+  match = /proxy_pass=([^&]*)/.exec(query);
+  if (match) {
+    proxy_expected_pass = match[1];
+  }
+
+  // proxy_realm=xxx
+  match = /proxy_realm=([^&]*)/.exec(query);
+  if (match) {
+    proxy_realm = match[1];
+  }
+
+  // huge=1
+  match = /huge=1/.exec(query);
+  if (match) {
+    huge = true;
+  }
+
+  // plugin=1
+  match = /plugin=1/.exec(query);
+  if (match) {
+    plugin = true;
+  }
+
+  // multiple=1
+  match = /multiple=([^&]*)/.exec(query);
+  if (match) {
+    authHeaderCount = match[1] + 0;
+  }
+
+  // anonymous=1
+  match = /anonymous=1/.exec(query);
+  if (match) {
+    anonymous = true;
+  }
+
+  // formauth=1
+  match = /formauth=1/.exec(query);
+  if (match) {
+    formauth = true;
+  }
+
+  // Look for an authentication header, if any, in the request.
+  //
+  // EG: Authorization: Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==
+  //
+  // This test only supports Basic auth. The value sent by the client is
+  // "username:password", obscured with base64 encoding.
+
+  let actual_user = "",
+    actual_pass = "",
+    authHeader,
+    authPresent = false;
+  if (request.hasHeader("Authorization")) {
+    authPresent = true;
+    authHeader = request.getHeader("Authorization");
+    match = /Basic (.+)/.exec(authHeader);
+    if (match.length != 2) {
+      throw new Error("Couldn't parse auth header: " + authHeader);
+    }
+
+    let userpass = atob(match[1]);
+    match = /(.*):(.*)/.exec(userpass);
+    if (match.length != 3) {
+      throw new Error("Couldn't decode auth header: " + userpass);
+    }
+    actual_user = match[1];
+    actual_pass = match[2];
+  }
+
+  let proxy_actual_user = "",
+    proxy_actual_pass = "";
+  if (request.hasHeader("Proxy-Authorization")) {
+    authHeader = request.getHeader("Proxy-Authorization");
+    match = /Basic (.+)/.exec(authHeader);
+    if (match.length != 2) {
+      throw new Error("Couldn't parse auth header: " + authHeader);
+    }
+
+    let userpass = atob(match[1]);
+    match = /(.*):(.*)/.exec(userpass);
+    if (match.length != 3) {
+      throw new Error("Couldn't decode auth header: " + userpass);
+    }
+    proxy_actual_user = match[1];
+    proxy_actual_pass = match[2];
+  }
+
+  // Don't request authentication if the credentials we got were what we
+  // expected.
+  if (expected_user == actual_user && expected_pass == actual_pass) {
+    requestAuth = false;
+  }
+  if (
+    proxy_expected_user == proxy_actual_user &&
+    proxy_expected_pass == proxy_actual_pass
+  ) {
+    requestProxyAuth = false;
+  }
+
+  if (anonymous) {
+    if (authPresent) {
+      response.setStatusLine(
+        "1.0",
+        400,
+        "Unexpected authorization header found"
+      );
+    } else {
+      response.setStatusLine("1.0", 200, "Authorization header not found");
+    }
+  } else if (requestProxyAuth) {
+    response.setStatusLine("1.0", 407, "Proxy authentication required");
+    for (let i = 0; i < authHeaderCount; ++i) {
+      response.setHeader(
+        "Proxy-Authenticate",
+        'basic realm="' + proxy_realm + '"',
+        true
+      );
+    }
+  } else if (requestAuth) {
+    if (formauth && authPresent) {
+      response.setStatusLine("1.0", 403, "Form authentication required");
+    } else {
+      response.setStatusLine("1.0", 401, "Authentication required");
+    }
+    for (let i = 0; i < authHeaderCount; ++i) {
+      response.setHeader(
+        "WWW-Authenticate",
+        'basic realm="' + realm + '"',
+        true
+      );
+    }
+  } else {
+    response.setStatusLine("1.0", 200, "OK");
+  }
+
+  response.setHeader("Content-Type", "application/xhtml+xml", false);
+  response.write("<html xmlns='http://www.w3.org/1999/xhtml'>");
+  response.write(
+    "<p>Login: <span id='ok'>" +
+      (requestAuth ? "FAIL" : "PASS") +
+      "</span></p>\n"
+  );
+  response.write(
+    "<p>Proxy: <span id='proxy'>" +
+      (requestProxyAuth ? "FAIL" : "PASS") +
+      "</span></p>\n"
+  );
+  response.write("<p>Auth: <span id='auth'>" + authHeader + "</span></p>\n");
+  response.write("<p>User: <span id='user'>" + actual_user + "</span></p>\n");
+  response.write("<p>Pass: <span id='pass'>" + actual_pass + "</span></p>\n");
+
+  if (huge) {
+    response.write("<div style='display: none'>");
+    for (let i = 0; i < 100000; i++) {
+      response.write("123456789\n");
+    }
+    response.write("</div>");
+    response.write(
+      "<span id='footnote'>This is a footnote after the huge content fill</span>"
+    );
+  }
+
+  if (plugin) {
+    response.write(
+      "<embed id='embedtest' style='width: 400px; height: 100px;' " +
+        "type='application/x-test'></embed>\n"
+    );
+  }
+
+  response.write("</html>");
+}
diff --git a/toolkit/components/passwordmgr/test/blank.html b/toolkit/components/passwordmgr/test/blank.html
new file mode 100644
index 0000000000..81ddc2235b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/blank.html
@@ -0,0 +1,8 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="utf-8">
+  </head>
+  <body>
+  </body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/.eslintrc.js b/toolkit/components/passwordmgr/test/browser/.eslintrc.js
new file mode 100644
index 0000000000..000a981cbe
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/.eslintrc.js
@@ -0,0 +1,7 @@
+"use strict";
+
+module.exports = {
+  rules: {
+    "no-var": "off",
+  },
+};
diff --git a/toolkit/components/passwordmgr/test/browser/authenticate.sjs b/toolkit/components/passwordmgr/test/browser/authenticate.sjs
new file mode 100644
index 0000000000..8f463dda6f
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/authenticate.sjs
@@ -0,0 +1,84 @@
+function handleRequest(request, response) {
+  var match;
+  var requestAuth = true;
+
+  // Allow the caller to drive how authentication is processed via the query.
+  // Eg, http://localhost:8888/authenticate.sjs?user=foo&realm=bar
+  // The extra ? allows the user/pass/realm checks to succeed if the name is
+  // at the beginning of the query string.
+  var query = "?" + request.queryString;
+
+  var expected_user = "test",
+    expected_pass = "testpass",
+    realm = "mochitest";
+
+  // user=xxx
+  match = /[^_]user=([^&]*)/.exec(query);
+  if (match) {
+    expected_user = match[1];
+  }
+
+  // pass=xxx
+  match = /[^_]pass=([^&]*)/.exec(query);
+  if (match) {
+    expected_pass = match[1];
+  }
+
+  // realm=xxx
+  match = /[^_]realm=([^&]*)/.exec(query);
+  if (match) {
+    realm = match[1];
+  }
+
+  // Look for an authentication header, if any, in the request.
+  //
+  // EG: Authorization: Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==
+  //
+  // This test only supports Basic auth. The value sent by the client is
+  // "username:password", obscured with base64 encoding.
+
+  var actual_user = "",
+    actual_pass = "",
+    authHeader;
+
+  if (request.hasHeader("Authorization")) {
+    authHeader = request.getHeader("Authorization");
+    match = /Basic (.+)/.exec(authHeader);
+    if (match.length != 2) {
+      throw new Error("Couldn't parse auth header: " + authHeader);
+    }
+
+    var userpass = atob(match[1]);
+    match = /(.*):(.*)/.exec(userpass);
+    if (match.length != 3) {
+      throw new Error("Couldn't decode auth header: " + userpass);
+    }
+    actual_user = match[1];
+    actual_pass = match[2];
+  }
+
+  // Don't request authentication if the credentials we got were what we
+  // expected.
+  if (expected_user == actual_user && expected_pass == actual_pass) {
+    requestAuth = false;
+  }
+
+  if (requestAuth) {
+    response.setStatusLine("1.0", 401, "Authentication required");
+    response.setHeader("WWW-Authenticate", 'basic realm="' + realm + '"', true);
+  } else {
+    response.setStatusLine("1.0", 200, "OK");
+  }
+
+  response.setHeader("Content-Type", "application/xhtml+xml", false);
+  response.write("<html xmlns='http://www.w3.org/1999/xhtml'>");
+  response.write(
+    "<p>Login: <span id='ok'>" +
+      (requestAuth ? "FAIL" : "PASS") +
+      "</span></p>\n"
+  );
+  response.write("<p>Auth: <span id='auth'>" + authHeader + "</span></p>\n");
+  response.write("<p>User: <span id='user'>" + actual_user + "</span></p>\n");
+  response.write("<p>Pass: <span id='pass'>" + actual_pass + "</span></p>\n");
+  response.write("</html>");
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser.toml b/toolkit/components/passwordmgr/test/browser/browser.toml
new file mode 100644
index 0000000000..53066c92d4
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser.toml
@@ -0,0 +1,248 @@
+[DEFAULT]
+support-files = [
+  "../formsubmit.sjs",
+  "authenticate.sjs",
+  "empty.html",
+  "form_basic.html",
+  "form_basic_iframe.html",
+  "form_basic_login.html",
+  "form_basic_login_fields_with_max_length.html",
+  "form_basic_no_username.html",
+  "form_basic_password_autocomplete_off.html",
+  "form_basic_password_autocomplete_new_password.html",
+  "form_basic_prefilled_password.html",
+  "form_basic_prefilled_username.html",
+  "form_basic_signup.html",
+  "form_cross_origin_insecure_action.html",
+  "form_cross_origin_secure_action.html",
+  "form_crossframe_no_outer_login_form.html",
+  "form_expanded.html",
+  "form_multipage.html",
+  "form_multiple_passwords.html",
+  "form_same_origin_action.html",
+  "form_unmasked_password_after_pageload.html",
+  "form_username_only.html",
+  "formless_basic.html",
+  "insecure_test_subframe.html",
+  "head.js",
+  "multiple_forms.html",
+  "../../../../../browser/components/aboutlogins/tests/browser/head.js",
+]
+
+
+["browser_DOMFormHasPassword.js"]
+
+["browser_DOMFormHasPossibleUsername.js"]
+
+["browser_DOMInputPasswordAdded.js"]
+skip-if = [
+  "os == 'linux'", # Bug 1337606
+  "os == 'mac'", # Bug 1337606
+]
+
+["browser_autocomplete_autofocus_with_frame.js"]
+support-files = ["form_autofocus_frame.html"]
+
+["browser_autocomplete_disabled_readonly_passwordField.js"]
+support-files = ["form_disabled_readonly_passwordField.html"]
+
+["browser_autocomplete_footer.js"]
+skip-if = ["!debug && os == 'linux' && bits == 64 && os_version == '18.04'"] # Bug 1591126
+
+["browser_autocomplete_generated_password_private_window.js"]
+
+["browser_autocomplete_import.js"]
+https_first_disabled = true
+skip-if = [
+  "os == 'mac'", # Bug 1775902
+  "os == 'win' && !debug", # Bug 1775902
+]
+
+["browser_autocomplete_insecure_warning.js"]
+
+["browser_autocomplete_primary_password.js"]
+
+["browser_autofill_hidden_document.js"]
+skip-if = [
+  "os == 'win' && os_version == '10.0' && debug", # bug 1530935
+  "apple_catalina && fission && !debug", # high frequency intermittent, Bug 1716486
+]
+
+["browser_autofill_http.js"]
+https_first_disabled = true
+skip-if = ["verify"]
+
+["browser_autofill_track_filled_logins.js"]
+
+["browser_basicAuth_multiTab.js"]
+fail-if = ["a11y_checks"] # Bug 1854452 clicked button may not be focusable
+skip-if = ["os == 'android'"]
+
+["browser_basicAuth_rateLimit.js"]
+
+["browser_basicAuth_switchTab.js"]
+skip-if = ["debug && os == 'mac'"] # Bug 1530566
+
+["browser_context_menu.js"]
+
+["browser_context_menu_autocomplete_interaction.js"]
+skip-if = ["verify"]
+
+["browser_context_menu_generated_password.js"]
+
+["browser_context_menu_iframe.js"]
+
+["browser_crossOriginSubmissionUsesCorrectOrigin.js"]
+support-files = ["form_cross_origin_secure_action.html"]
+
+["browser_deleteLoginsBackup.js"]
+skip-if = ["os == 'android'"]
+
+["browser_doorhanger_autocomplete_values.js"]
+fail-if = ["a11y_checks"] # Bug 1854452 clicked password-notification-username-dropmaker may not be focusable and/or labeled
+
+["browser_doorhanger_autofill_then_save_password.js"]
+
+["browser_doorhanger_crossframe.js"]
+support-files = [
+  "form_crossframe.html",
+  "form_crossframe_inner.html",
+]
+
+["browser_doorhanger_dismissed_for_ccnumber.js"]
+
+["browser_doorhanger_empty_password.js"]
+
+["browser_doorhanger_form_password_edit.js"]
+
+["browser_doorhanger_generated_password.js"]
+support-files = [
+  "form_basic_with_confirm_field.html",
+  "form_password_change.html",
+]
+skip-if = [
+  "os == 'linux'", # Bug 1729196
+  "win11_2009 && bits == 64", # Bug 1729196
+  "os == 'mac' && debug", # Bug 1729196
+]
+
+["browser_doorhanger_httpsUpgrade.js"]
+support-files = [
+  "subtst_notifications_1.html",
+  "subtst_notifications_8.html",
+]
+
+["browser_doorhanger_multipage_form.js"]
+
+["browser_doorhanger_password_edits.js"]
+
+["browser_doorhanger_promptToChangePassword.js"]
+
+["browser_doorhanger_remembering.js"]
+
+["browser_doorhanger_replace_dismissed_with_visible_while_opening.js"]
+
+["browser_doorhanger_save_password.js"]
+skip-if = ["a11y_checks"] # Bugs 1858041, 1854454 and 1824058 for causing intermittent crashes
+
+["browser_doorhanger_submit_telemetry.js"]
+fail-if = ["a11y_checks"] # Bug 1854452 clicked dropmaker may not be focusable
+skip-if = [
+  "tsan", # Bug 1661305
+  "os == 'linux' && debug", # Bug 1658056
+  "os == 'linux' && asan", # Bug 1695395
+]
+
+["browser_doorhanger_target_blank.js"]
+support-files = ["subtst_notifications_12_target_blank.html"]
+
+["browser_doorhanger_toggles.js"]
+
+["browser_doorhanger_username_edits.js"]
+
+["browser_doorhanger_window_open.js"]
+support-files = [
+  "subtst_notifications_11.html",
+  "subtst_notifications_11_popup.html",
+]
+skip-if = ["os == 'linux'"] # Bug 1312981, bug 1313136
+
+["browser_entry_point_telemetry.js"]
+
+["browser_exceptions_dialog.js"]
+
+["browser_fileURIOrigin.js"]
+
+["browser_focus_before_first_DOMContentLoaded.js"]
+support-files = ["file_focus_before_DOMContentLoaded.sjs"]
+
+["browser_form_history_fallback.js"]
+https_first_disabled = true # TODO remove that line and move test to HTTPS, see Bug 1776350
+skip-if = ["os == 'linux' && debug"] # Bug 1334336
+support-files = [
+  "subtst_notifications_1.html",
+  "subtst_notifications_2.html",
+  "subtst_notifications_2pw_0un.html",
+  "subtst_notifications_2pw_1un_1text.html",
+  "subtst_notifications_3.html",
+  "subtst_notifications_4.html",
+  "subtst_notifications_5.html",
+  "subtst_notifications_6.html",
+  "subtst_notifications_8.html",
+  "subtst_notifications_9.html",
+  "subtst_notifications_10.html",
+  "subtst_notifications_change_p.html",
+]
+
+["browser_formless_submit_chrome.js"]
+skip-if = ["tsan"] # Bug 1683730
+
+["browser_glean_pwmgr_form_autofill_result.js"]
+
+["browser_insecurePasswordConsoleWarning.js"]
+https_first_disabled = true
+skip-if = ["verify"]
+
+["browser_isProbablyASignUpForm.js"]
+support-files = ["form_signup_detection.html"]
+
+["browser_localip_frame.js"]
+skip-if = [
+  "os == 'mac' && bits == 64", # Bug 1683848
+  "os == 'linux' && !debug && bits == 64", # Bug 1683848
+]
+
+["browser_message_onFormSubmit.js"]
+
+["browser_openPasswordManager.js"]
+
+["browser_preselect_login.js"]
+fail-if = ["a11y_checks"] # Bug 1854452 clicked ac-secondary-action may not be labeled
+skip-if = [
+  "os == 'linux' && (asan || tsan || debug)", # Bug 1840479
+  "os == 'win' && (asan || debug)", # Bug 1840479
+]
+
+["browser_private_window.js"]
+support-files = [
+  "subtst_privbrowsing_1.html",
+  "form_password_change.html",
+]
+skip-if = [
+  "os == 'linux' && bits == 64 && os_version == '18.04' && !debug", # Bug 1744976
+  "os == 'win' && os_version == '10.0' && debug", # Bug 1782656
+]
+
+["browser_proxyAuth_prompt.js"]
+skip-if = ["os == 'android'"]
+
+["browser_relay_telemetry.js"]
+
+["browser_telemetry_SignUpFormRuleset.js"]
+
+["browser_test_changeContentInputValue.js"]
+
+["browser_username_only_form_telemetry.js"]
+
+["browser_username_select_dialog.js"]
+support-files = ["subtst_notifications_change_p.html"]
diff --git a/toolkit/components/passwordmgr/test/browser/browser_DOMFormHasPassword.js b/toolkit/components/passwordmgr/test/browser/browser_DOMFormHasPassword.js
new file mode 100644
index 0000000000..a7dfe071dc
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_DOMFormHasPassword.js
@@ -0,0 +1,152 @@
+const ids = {
+  INPUT_ID: "input1",
+  FORM1_ID: "form1",
+  FORM2_ID: "form2",
+  CHANGE_INPUT_ID: "input2",
+};
+
+function task(contentIds) {
+  let resolve;
+  let promise = new Promise(r => {
+    resolve = r;
+  });
+
+  function unexpectedContentEvent(evt) {
+    Assert.ok(false, "Received a " + evt.type + " event on content");
+  }
+
+  var gDoc = null;
+
+  addEventListener("load", tabLoad, true);
+
+  function tabLoad() {
+    if (content.location.href == "about:blank") {
+      return;
+    }
+    removeEventListener("load", tabLoad, true);
+
+    gDoc = content.document;
+    gDoc.addEventListener("DOMFormHasPassword", unexpectedContentEvent);
+    addEventListener("DOMFormHasPassword", unexpectedContentEvent);
+    gDoc.defaultView.setTimeout(test_inputAdd, 0);
+  }
+
+  function test_inputAdd() {
+    addEventListener("DOMFormHasPassword", test_inputAddHandler, {
+      once: true,
+      capture: true,
+    });
+    let input = gDoc.createElementNS("http://www.w3.org/1999/xhtml", "input");
+    input.setAttribute("type", "password");
+    input.setAttribute("id", contentIds.INPUT_ID);
+    input.setAttribute("data-test", "unique-attribute");
+    gDoc.getElementById(contentIds.FORM1_ID).appendChild(input);
+  }
+
+  function test_inputAddHandler(evt) {
+    evt.stopPropagation();
+    Assert.equal(
+      evt.target.id,
+      contentIds.FORM1_ID,
+      evt.type + " event targets correct form element (added password element)"
+    );
+    gDoc.defaultView.setTimeout(test_inputChangeForm, 0);
+  }
+
+  function test_inputChangeForm() {
+    addEventListener("DOMFormHasPassword", test_inputChangeFormHandler, {
+      once: true,
+      capture: true,
+    });
+    let input = gDoc.getElementById(contentIds.INPUT_ID);
+    input.setAttribute("form", contentIds.FORM2_ID);
+  }
+
+  function test_inputChangeFormHandler(evt) {
+    evt.stopPropagation();
+    Assert.equal(
+      evt.target.id,
+      contentIds.FORM2_ID,
+      evt.type + " event targets correct form element (changed form)"
+    );
+    gDoc.defaultView.setTimeout(test_inputChangesType, 0);
+  }
+
+  function test_inputChangesType() {
+    addEventListener("DOMFormHasPassword", test_inputChangesTypeHandler, {
+      once: true,
+      capture: true,
+    });
+    let input = gDoc.getElementById(contentIds.CHANGE_INPUT_ID);
+    input.setAttribute("type", "password");
+  }
+
+  function test_inputChangesTypeHandler(evt) {
+    evt.stopPropagation();
+    Assert.equal(
+      evt.target.id,
+      contentIds.FORM1_ID,
+      evt.type + " event targets correct form element (changed type)"
+    );
+    gDoc.defaultView.setTimeout(finish, 0);
+  }
+
+  function finish() {
+    removeEventListener("DOMFormHasPassword", unexpectedContentEvent);
+    gDoc.removeEventListener("DOMFormHasPassword", unexpectedContentEvent);
+    resolve();
+  }
+
+  return promise;
+}
+
+add_task(async function test_disconnectedInputs() {
+  const tab = (gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser));
+  await ContentTask.spawn(tab.linkedBrowser, [], async () => {
+    const unexpectedEvent = evt => {
+      Assert.ok(
+        false,
+        `${evt.type} should not be fired for disconnected forms.`
+      );
+    };
+
+    addEventListener("DOMFormHasPassword", unexpectedEvent);
+
+    const form = content.document.createElement("form");
+    const passwordInput = content.document.createElement("input");
+    passwordInput.setAttribute("type", "password");
+    form.appendChild(passwordInput);
+
+    // Delay the execution for a bit to allow time for any asynchronously
+    // dispatched 'DOMFormHasPassword' events to be processed.
+    // This is necessary because such events might not be triggered immediately,
+    // and we want to ensure that if they are dispatched, they are captured
+    // before we remove the event listener.
+    // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+    await new Promise(resolve => setTimeout(resolve, 50));
+    removeEventListener("DOMFormHasPassword", unexpectedEvent);
+  });
+
+  Assert.ok(true, "Test completed");
+  gBrowser.removeCurrentTab();
+});
+
+add_task(async function () {
+  let tab = (gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser));
+
+  let promise = ContentTask.spawn(tab.linkedBrowser, ids, task);
+  BrowserTestUtils.startLoadingURIString(
+    tab.linkedBrowser,
+    `data:text/html;charset=utf-8,
+      <html><body>
+      <form id="${ids.FORM1_ID}">
+        <input id="${ids.CHANGE_INPUT_ID}">
+      </form>
+      <form id="${ids.FORM2_ID}"></form>
+      </body></html>`
+  );
+  await promise;
+
+  Assert.ok(true, "Test completed");
+  gBrowser.removeCurrentTab();
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_DOMFormHasPossibleUsername.js b/toolkit/components/passwordmgr/test/browser/browser_DOMFormHasPossibleUsername.js
new file mode 100644
index 0000000000..fbc8a7a73a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_DOMFormHasPossibleUsername.js
@@ -0,0 +1,254 @@
+const ids = {
+  INPUT_ID: "input1",
+  FORM1_ID: "form1",
+  FORM2_ID: "form2",
+  CHANGE_INPUT_ID: "input2",
+  INPUT_TYPE: "",
+};
+
+function task({ contentIds, expected }) {
+  let resolve;
+  let promise = new Promise(r => {
+    resolve = r;
+  });
+
+  function unexpectedContentEvent(evt) {
+    Assert.ok(false, "Received a " + evt.type + " event on content");
+  }
+
+  var gDoc = null;
+
+  addEventListener("load", tabLoad, true);
+
+  function tabLoad() {
+    if (content.location.href == "about:blank") {
+      return;
+    }
+    removeEventListener("load", tabLoad, true);
+
+    gDoc = content.document;
+    gDoc.addEventListener("DOMFormHasPossibleUsername", unexpectedContentEvent);
+    addEventListener("DOMFormHasPossibleUsername", unexpectedContentEvent);
+    gDoc.defaultView.setTimeout(test_inputAdd, 0);
+  }
+
+  function test_inputAdd() {
+    if (expected) {
+      addEventListener("DOMFormHasPossibleUsername", test_inputAddHandler, {
+        once: true,
+        capture: true,
+      });
+    } else {
+      gDoc.defaultView.setTimeout(test_inputAddHandler, 0);
+    }
+    let input = gDoc.createElementNS("http://www.w3.org/1999/xhtml", "input");
+    input.setAttribute("type", contentIds.INPUT_TYPE);
+    input.setAttribute("id", contentIds.INPUT_ID);
+    input.setAttribute("data-test", "unique-attribute");
+    gDoc.getElementById(contentIds.FORM1_ID).appendChild(input);
+  }
+
+  function test_inputAddHandler(evt) {
+    if (expected) {
+      evt.stopPropagation();
+      Assert.equal(
+        evt.target.id,
+        contentIds.FORM1_ID,
+        evt.type +
+          " event targets correct form element (added possible username element)"
+      );
+    }
+    gDoc.defaultView.setTimeout(test_inputChangeForm, 0);
+  }
+
+  function test_inputChangeForm() {
+    if (expected) {
+      addEventListener(
+        "DOMFormHasPossibleUsername",
+        test_inputChangeFormHandler,
+        { once: true, capture: true }
+      );
+    } else {
+      gDoc.defaultView.setTimeout(test_inputChangeFormHandler, 0);
+    }
+    let input = gDoc.getElementById(contentIds.INPUT_ID);
+    input.setAttribute("form", contentIds.FORM2_ID);
+  }
+
+  function test_inputChangeFormHandler(evt) {
+    if (expected) {
+      evt.stopPropagation();
+      Assert.equal(
+        evt.target.id,
+        contentIds.FORM2_ID,
+        evt.type + " event targets correct form element (changed form)"
+      );
+    }
+    // TODO(Bug 1864405): Refactor this test to not expect a DOM event
+    // when the type is set to the same value
+    const nextTask =
+      expected && contentIds.INPUT_TYPE === "text"
+        ? finish
+        : test_inputChangesType;
+    gDoc.defaultView.setTimeout(nextTask, 0);
+  }
+
+  function test_inputChangesType() {
+    if (expected) {
+      addEventListener(
+        "DOMFormHasPossibleUsername",
+        test_inputChangesTypeHandler,
+        { once: true, capture: true }
+      );
+    } else {
+      gDoc.defaultView.setTimeout(test_inputChangesTypeHandler, 0);
+    }
+    let input = gDoc.getElementById(contentIds.CHANGE_INPUT_ID);
+    input.setAttribute("type", contentIds.INPUT_TYPE);
+  }
+
+  function test_inputChangesTypeHandler(evt) {
+    if (expected) {
+      evt.stopPropagation();
+      Assert.equal(
+        evt.target.id,
+        contentIds.FORM1_ID,
+        evt.type + " event targets correct form element (changed type)"
+      );
+    }
+    gDoc.defaultView.setTimeout(finish, 0);
+  }
+
+  function finish() {
+    removeEventListener("DOMFormHasPossibleUsername", unexpectedContentEvent);
+    gDoc.removeEventListener(
+      "DOMFormHasPossibleUsername",
+      unexpectedContentEvent
+    );
+    resolve();
+  }
+
+  return promise;
+}
+
+add_setup(async function () {
+  Services.prefs.setBoolPref("signon.usernameOnlyForm.enabled", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.usernameOnlyForm.enabled");
+  });
+});
+
+add_task(async function test_disconnectedInputs() {
+  const tab = (gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser));
+  await ContentTask.spawn(tab.linkedBrowser, [], async () => {
+    const unexpectedEvent = evt => {
+      Assert.ok(
+        false,
+        `${evt.type} should not be fired for disconnected forms.`
+      );
+    };
+
+    addEventListener("DOMFormHasPossibleUsername", unexpectedEvent);
+    const form = content.document.createElement("form");
+    const textInput = content.document.createElement("input");
+    textInput.setAttribute("type", "text");
+    form.appendChild(textInput);
+
+    // Delay the execution for a bit to allow time for any asynchronously
+    // dispatched 'DOMFormHasPossibleUsername' events to be processed.
+    // This is necessary because such events might not be triggered immediately,
+    // and we want to ensure that if they are dispatched, they are captured
+    // before we remove the event listener.
+    // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+    await new Promise(resolve => setTimeout(resolve, 50));
+    removeEventListener("DOMFormHasPossibleUsername", unexpectedEvent);
+  });
+
+  Assert.ok(true, "Test completed");
+  gBrowser.removeCurrentTab();
+});
+
+add_task(async function test_usernameOnlyForm() {
+  for (let type of ["text", "email"]) {
+    let tab = (gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser));
+
+    ids.INPUT_TYPE = type;
+    let promise = ContentTask.spawn(
+      tab.linkedBrowser,
+      { contentIds: ids, expected: true },
+      task
+    );
+    BrowserTestUtils.startLoadingURIString(
+      tab.linkedBrowser,
+      `data:text/html;charset=utf-8,
+        <html><body>
+        <form id="${ids.FORM1_ID}">
+          <input id="${ids.CHANGE_INPUT_ID}">
+        </form>
+        <form id="${ids.FORM2_ID}"></form>
+        </body></html>`
+    );
+    await promise;
+
+    Assert.ok(true, "Test completed");
+    gBrowser.removeCurrentTab();
+  }
+});
+
+add_task(async function test_nonSupportedInputType() {
+  for (let type of ["url", "tel", "number"]) {
+    let tab = (gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser));
+
+    ids.INPUT_TYPE = type;
+    let promise = ContentTask.spawn(
+      tab.linkedBrowser,
+      { contentIds: ids, expected: false },
+      task
+    );
+    BrowserTestUtils.startLoadingURIString(
+      tab.linkedBrowser,
+      `data:text/html;charset=utf-8,
+        <html><body>
+        <form id="${ids.FORM1_ID}">
+          <input id="${ids.CHANGE_INPUT_ID}">
+        </form>
+        <form id="${ids.FORM2_ID}"></form>
+        </body></html>`
+    );
+    await promise;
+
+    Assert.ok(true, "Test completed");
+    gBrowser.removeCurrentTab();
+  }
+});
+
+add_task(async function test_usernameOnlyFormPrefOff() {
+  Services.prefs.setBoolPref("signon.usernameOnlyForm.enabled", false);
+
+  for (let type of ["text", "email"]) {
+    let tab = (gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser));
+
+    ids.INPUT_TYPE = type;
+    let promise = ContentTask.spawn(
+      tab.linkedBrowser,
+      { contentIds: ids, expected: false },
+      task
+    );
+    BrowserTestUtils.startLoadingURIString(
+      tab.linkedBrowser,
+      `data:text/html;charset=utf-8,
+        <html><body>
+        <form id="${ids.FORM1_ID}">
+          <input id="${ids.CHANGE_INPUT_ID}">
+        </form>
+        <form id="${ids.FORM2_ID}"></form>
+        </body></html>`
+    );
+    await promise;
+
+    Assert.ok(true, "Test completed");
+    gBrowser.removeCurrentTab();
+  }
+
+  Services.prefs.clearUserPref("signon.usernameOnlyForm.enabled");
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_DOMInputPasswordAdded.js b/toolkit/components/passwordmgr/test/browser/browser_DOMInputPasswordAdded.js
new file mode 100644
index 0000000000..fe7e849baa
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_DOMInputPasswordAdded.js
@@ -0,0 +1,101 @@
+const consts = {
+  HTML_NS: "http://www.w3.org/1999/xhtml",
+
+  INPUT_ID: "input1",
+  FORM1_ID: "form1",
+  FORM2_ID: "form2",
+  CHANGE_INPUT_ID: "input2",
+  BODY_INPUT_ID: "input3",
+};
+
+function task(contentConsts) {
+  let resolve;
+  let promise = new Promise(r => {
+    resolve = r;
+  });
+
+  function unexpectedContentEvent(evt) {
+    Assert.ok(false, "Received a " + evt.type + " event on content");
+  }
+
+  var gDoc = null;
+
+  addEventListener("load", tabLoad, true);
+
+  function tabLoad() {
+    removeEventListener("load", tabLoad, true);
+    gDoc = content.document;
+    // These events shouldn't escape to content.
+    gDoc.addEventListener("DOMInputPasswordAdded", unexpectedContentEvent);
+    gDoc.defaultView.setTimeout(test_inputAddOutsideForm, 0);
+  }
+
+  function test_inputAddOutsideForm() {
+    addEventListener(
+      "DOMInputPasswordAdded",
+      test_inputAddOutsideFormHandler,
+      false
+    );
+    let input = gDoc.createElementNS(contentConsts.HTML_NS, "input");
+    input.setAttribute("type", "password");
+    input.setAttribute("id", contentConsts.BODY_INPUT_ID);
+    input.setAttribute("data-test", "unique-attribute");
+    gDoc.body.appendChild(input);
+    info("Done appending the input element to the body");
+  }
+
+  function test_inputAddOutsideFormHandler(evt) {
+    removeEventListener(evt.type, test_inputAddOutsideFormHandler, false);
+    Assert.equal(
+      evt.target.id,
+      contentConsts.BODY_INPUT_ID,
+      evt.type +
+        " event targets correct input element (added password element outside form)"
+    );
+    gDoc.defaultView.setTimeout(test_inputChangesType, 0);
+  }
+
+  function test_inputChangesType() {
+    addEventListener(
+      "DOMInputPasswordAdded",
+      test_inputChangesTypeHandler,
+      false
+    );
+    let input = gDoc.getElementById(contentConsts.CHANGE_INPUT_ID);
+    input.setAttribute("type", "password");
+  }
+
+  function test_inputChangesTypeHandler(evt) {
+    removeEventListener(evt.type, test_inputChangesTypeHandler, false);
+    Assert.equal(
+      evt.target.id,
+      contentConsts.CHANGE_INPUT_ID,
+      evt.type + " event targets correct input element (changed type)"
+    );
+    gDoc.defaultView.setTimeout(completeTest, 0);
+  }
+
+  function completeTest() {
+    Assert.ok(true, "Test completed");
+    gDoc.removeEventListener("DOMInputPasswordAdded", unexpectedContentEvent);
+    resolve();
+  }
+
+  return promise;
+}
+
+add_task(async function () {
+  let tab = (gBrowser.selectedTab = BrowserTestUtils.addTab(gBrowser));
+  let promise = ContentTask.spawn(tab.linkedBrowser, consts, task);
+  BrowserTestUtils.startLoadingURIString(
+    tab.linkedBrowser,
+    `data:text/html;charset=utf-8,
+      <html><body>
+        <input id="${consts.CHANGE_INPUT_ID}" />
+      </body>
+      </html>
+    `
+  );
+  await promise;
+  gBrowser.removeCurrentTab();
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_autocomplete_autofocus_with_frame.js b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_autofocus_with_frame.js
new file mode 100644
index 0000000000..551e1b939a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_autofocus_with_frame.js
@@ -0,0 +1,48 @@
+const TEST_URL_PATH = "https://example.org" + DIRECTORY_PATH;
+
+add_setup(async function () {
+  let login = LoginTestUtils.testData.formLogin({
+    origin: "https://example.org",
+    formActionOrigin: "https://example.org",
+    username: "username1",
+    password: "password1",
+  });
+  await Services.logins.addLoginAsync(login);
+  login = LoginTestUtils.testData.formLogin({
+    origin: "https://example.org",
+    formActionOrigin: "https://example.org",
+    username: "username2",
+    password: "password2",
+  });
+  await Services.logins.addLoginAsync(login);
+});
+
+// Verify that the autocomplete popup opens when the username field in autofocused.
+add_task(async function test_autofocus_autocomplete() {
+  let popup = document.getElementById("PopupAutoComplete");
+  let popupShown = BrowserTestUtils.waitForEvent(popup, "popupshown");
+
+  let formFilled = listenForTestNotification("FormProcessed");
+  let tab = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    TEST_URL_PATH + "form_autofocus_frame.html"
+  );
+
+  await formFilled;
+  await popupShown;
+
+  Assert.ok(true, "popup opened");
+
+  let promiseHidden = BrowserTestUtils.waitForEvent(popup, "popuphidden");
+  popup.firstChild.getItemAtIndex(0).click();
+  await promiseHidden;
+
+  Assert.ok(true, "popup closed");
+
+  let password = await SpecialPowers.spawn(tab.linkedBrowser, [], () => {
+    return content.document.getElementById("form-basic-password").value;
+  });
+  Assert.equal(password, "password1", "password filled in");
+
+  gBrowser.removeTab(tab);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_autocomplete_disabled_readonly_passwordField.js b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_disabled_readonly_passwordField.js
new file mode 100644
index 0000000000..f6e0a62678
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_disabled_readonly_passwordField.js
@@ -0,0 +1,138 @@
+const TEST_URL_PATH =
+  "https://example.org" +
+  DIRECTORY_PATH +
+  "form_disabled_readonly_passwordField.html";
+const FIRST_ITEM = 0;
+
+/**
+ * Add two logins to prevent autofilling, but the AutocompletePopup will be displayed
+ */
+add_setup(async () => {
+  let login1 = LoginTestUtils.testData.formLogin({
+    origin: "https://example.org",
+    formActionOrigin: "https://example.org",
+    username: "username1",
+    password: "password1",
+  });
+
+  let login2 = LoginTestUtils.testData.formLogin({
+    origin: "https://example.org",
+    formActionOrigin: "https://example.org",
+    username: "username2",
+    password: "password2",
+  });
+
+  await Services.logins.addLogins([login1, login2]);
+});
+
+add_task(
+  async function test_autocomplete_for_usernameField_with_disabled_passwordField() {
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url: TEST_URL_PATH,
+      },
+      async function (browser) {
+        let popup = document.getElementById("PopupAutoComplete");
+
+        Assert.ok(popup, "Got Popup");
+
+        await openACPopup(
+          popup,
+          browser,
+          "#login_form_disabled_password input[name=username]"
+        );
+
+        info("Popup opened");
+
+        let promiseHidden = BrowserTestUtils.waitForEvent(popup, "popuphidden");
+        popup.firstChild.getItemAtIndex(FIRST_ITEM).click();
+        await promiseHidden;
+
+        info("Popup closed");
+
+        let [username, password] = await SpecialPowers.spawn(
+          browser,
+          [],
+          async () => {
+            let doc = content.document;
+            let contentUsername = doc.querySelector(
+              "#login_form_disabled_password input[name=username]"
+            ).value;
+            let contentPassword = doc.querySelector(
+              "#login_form_disabled_password input[name=password]"
+            ).value;
+            return [contentUsername, contentPassword];
+          }
+        );
+        Assert.equal(
+          username,
+          "username1",
+          "Username was autocompleted with correct value."
+        );
+        Assert.equal(
+          password,
+          "",
+          "Password was not autocompleted, because field is disabled."
+        );
+      }
+    );
+  }
+);
+
+add_task(
+  async function test_autocomplete_for_usernameField_with_readonly_passwordField() {
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url: TEST_URL_PATH,
+      },
+      async function (browser) {
+        let popup = document.getElementById("PopupAutoComplete");
+
+        Assert.ok(popup, "Got Popup");
+
+        await openACPopup(
+          popup,
+          browser,
+          "#login_form_readonly_password input[name=username]"
+        );
+
+        info("Popup opened");
+
+        let promiseHidden = BrowserTestUtils.waitForEvent(popup, "popuphidden");
+        popup.firstChild.getItemAtIndex(FIRST_ITEM).click();
+        await promiseHidden;
+
+        info("Popup closed");
+
+        let [username, password] = await SpecialPowers.spawn(
+          browser,
+          [],
+          async () => {
+            let doc = content.document;
+            let contentUsername = doc.querySelector(
+              "#login_form_readonly_password input[name=username]"
+            ).value;
+            info(contentUsername);
+            let contentPassword = doc.querySelector(
+              "#login_form_readonly_password input[name=password]"
+            ).value;
+            info(contentPassword);
+            return [contentUsername, contentPassword];
+          }
+        );
+        Assert.equal(
+          username,
+          "username1",
+          "Username was autocompleted with correct value."
+        );
+        Assert.equal(
+          password,
+          "",
+          "Password was not autocompleted, because field is readonly."
+        );
+      }
+    );
+  }
+);
diff --git a/toolkit/components/passwordmgr/test/browser/browser_autocomplete_footer.js b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_footer.js
new file mode 100644
index 0000000000..6660daec99
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_footer.js
@@ -0,0 +1,125 @@
+"use strict";
+
+const TEST_ORIGIN = "https://example.com";
+const BASIC_FORM_PAGE_PATH = DIRECTORY_PATH + "form_basic.html";
+
+function loginList() {
+  return [
+    LoginTestUtils.testData.formLogin({
+      origin: "https://example.com",
+      formActionOrigin: "https://example.com",
+      username: "username",
+      password: "password",
+    }),
+    LoginTestUtils.testData.formLogin({
+      origin: "https://example.com",
+      formActionOrigin: "https://example.com",
+      username: "username2",
+      password: "password2",
+    }),
+  ];
+}
+
+/**
+ * Initialize logins and set prefs needed for the test.
+ */
+add_task(async function test_initialize() {
+  Services.prefs.setBoolPref("signon.showAutoCompleteFooter", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.showAutoCompleteFooter");
+  });
+
+  await Services.logins.addLogins(loginList());
+});
+
+add_task(async function test_autocomplete_footer_onclick() {
+  let url = TEST_ORIGIN + BASIC_FORM_PAGE_PATH;
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function footer_onclick(browser) {
+      let popup = document.getElementById("PopupAutoComplete");
+      Assert.ok(popup, "Got popup");
+
+      await openACPopup(popup, browser, "#form-basic-username");
+
+      let footer = popup.querySelector(`[originaltype="loginsFooter"]`);
+      Assert.ok(footer, "Got footer richlistitem");
+
+      await TestUtils.waitForCondition(() => {
+        return !EventUtils.isHidden(footer);
+      }, "Waiting for footer to become visible");
+
+      let openingFunc = () => EventUtils.synthesizeMouseAtCenter(footer, {});
+      let passwordManager = await openPasswordManager(openingFunc, false);
+
+      info("Password Manager was opened");
+
+      Assert.ok(
+        !passwordManager.filterValue,
+        "Search string should not be set to filter logins"
+      );
+
+      // open_management
+      await LoginTestUtils.telemetry.waitForEventCount(1);
+
+      // Check event telemetry recorded when opening management UI
+      TelemetryTestUtils.assertEvents(
+        [["pwmgr", "open_management", "autocomplete"]],
+        { category: "pwmgr", method: "open_management" },
+        { clear: true, process: "content" }
+      );
+
+      await passwordManager.close();
+      await closePopup(popup);
+    }
+  );
+});
+
+add_task(async function test_autocomplete_footer_keydown() {
+  let url = TEST_ORIGIN + BASIC_FORM_PAGE_PATH;
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function footer_enter_keydown(browser) {
+      let popup = document.getElementById("PopupAutoComplete");
+      Assert.ok(popup, "Got popup");
+
+      await openACPopup(popup, browser, "#form-basic-username");
+
+      let footer = popup.querySelector(`[originaltype="loginsFooter"]`);
+      Assert.ok(footer, "Got footer richlistitem");
+
+      await TestUtils.waitForCondition(() => {
+        return !EventUtils.isHidden(footer);
+      }, "Waiting for footer to become visible");
+
+      await EventUtils.synthesizeKey("KEY_ArrowDown");
+      await EventUtils.synthesizeKey("KEY_ArrowDown");
+      await EventUtils.synthesizeKey("KEY_ArrowDown");
+      let openingFunc = () => EventUtils.synthesizeKey("KEY_Enter");
+
+      let passwordManager = await openPasswordManager(openingFunc, false);
+      info("Login dialog was opened");
+
+      Assert.ok(
+        !passwordManager.filterValue,
+        "Search string should not be set to filter logins"
+      );
+
+      // Check event telemetry recorded when opening management UI
+      TelemetryTestUtils.assertEvents(
+        [["pwmgr", "open_management", "autocomplete"]],
+        { category: "pwmgr", method: "open_management" },
+        { clear: true, process: "content" }
+      );
+
+      await passwordManager.close();
+      await closePopup(popup);
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_autocomplete_generated_password_private_window.js b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_generated_password_private_window.js
new file mode 100644
index 0000000000..f28a7a1d52
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_generated_password_private_window.js
@@ -0,0 +1,111 @@
+// The origin for the test URIs.
+const TEST_ORIGIN = "https://example.com";
+const FORM_PAGE_PATH =
+  "/browser/toolkit/components/passwordmgr/test/browser/form_basic.html";
+const passwordInputSelector = "#form-basic-password";
+
+add_setup(async function () {
+  Services.telemetry.clearEvents();
+  TelemetryTestUtils.assertEvents([], {
+    category: "pwmgr",
+    method: "autocomplete_shown",
+  });
+});
+
+add_task(async function test_autocomplete_new_password_popup_item_visible() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN,
+    },
+    async function (browser) {
+      info("Generate and cache a password for a non-private context");
+      let lmp =
+        browser.browsingContext.currentWindowGlobal.getActor("LoginManager");
+      await lmp.getGeneratedPassword();
+      Assert.equal(
+        LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().size,
+        1,
+        "Non-Private password should be cached"
+      );
+    }
+  );
+
+  await LoginTestUtils.addLogin({ username: "username", password: "pass1" });
+  const win = await BrowserTestUtils.openNewBrowserWindow({ private: true });
+  const doc = win.document;
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: win.gBrowser,
+      url: TEST_ORIGIN + FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      await ContentTask.spawn(
+        browser,
+        [passwordInputSelector],
+        function openAutocomplete(sel) {
+          content.document.querySelector(sel).autocomplete = "new-password";
+        }
+      );
+
+      let popup = doc.getElementById("PopupAutoComplete");
+      Assert.ok(popup, "Got popup");
+      await openACPopup(popup, browser, passwordInputSelector);
+
+      let item = popup.querySelector(`[originaltype="generatedPassword"]`);
+      Assert.ok(item, "Should get 'Generate password' richlistitem");
+
+      let onPopupClosed = BrowserTestUtils.waitForCondition(
+        () => !popup.popupOpen,
+        "Popup should get closed"
+      );
+
+      await TestUtils.waitForTick();
+
+      TelemetryTestUtils.assertEvents(
+        [["pwmgr", "autocomplete_shown", "generatedpassword"]],
+        { category: "pwmgr", method: "autocomplete_shown" }
+      );
+
+      await closePopup(popup);
+      await onPopupClosed;
+    }
+  );
+
+  let lastPBContextExitedPromise = TestUtils.topicObserved(
+    "last-pb-context-exited"
+  ).then(() => TestUtils.waitForTick());
+  await BrowserTestUtils.closeWindow(win);
+  await lastPBContextExitedPromise;
+  Assert.equal(
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().size,
+    1,
+    "Only private-context passwords should be cleared"
+  );
+});
+
+add_task(async function test_autocomplete_menu_item_enabled() {
+  const win = await BrowserTestUtils.openNewBrowserWindow({ private: true });
+  const doc = win.document;
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: win.gBrowser,
+      url: TEST_ORIGIN + FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser);
+      await openPasswordContextMenu(browser, passwordInputSelector);
+      let generatedPasswordItem = doc.getElementById(
+        "fill-login-generated-password"
+      );
+      Assert.equal(
+        generatedPasswordItem.disabled,
+        false,
+        "Generate password context menu item should be enabled in PB mode"
+      );
+      await closePopup(document.getElementById("contentAreaContextMenu"));
+    }
+  );
+  await BrowserTestUtils.closeWindow(win);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_autocomplete_import.js b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_import.js
new file mode 100644
index 0000000000..7d8ec9f016
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_import.js
@@ -0,0 +1,258 @@
+const { ChromeMigrationUtils } = ChromeUtils.importESModule(
+  "resource:///modules/ChromeMigrationUtils.sys.mjs"
+);
+const { ExperimentAPI } = ChromeUtils.importESModule(
+  "resource://nimbus/ExperimentAPI.sys.mjs"
+);
+const { ExperimentFakes } = ChromeUtils.importESModule(
+  "resource://testing-common/NimbusTestUtils.sys.mjs"
+);
+const { sinon } = ChromeUtils.importESModule(
+  "resource://testing-common/Sinon.sys.mjs"
+);
+
+// Dummy migrator to change and detect importable behavior.
+const gTestMigrator = {
+  profiles: [],
+
+  getSourceProfiles() {
+    return this.profiles;
+  },
+
+  migrate: sinon
+    .stub()
+    .callsFake(() =>
+      LoginTestUtils.addLogin({ username: "import", password: "pass" })
+    ),
+};
+
+// Showing importables updates counts delayed, so adjust and cleanup.
+add_setup(async function setup() {
+  const debounce = sinon
+    .stub(LoginManagerParent, "SUGGEST_IMPORT_DEBOUNCE_MS")
+    .value(0);
+  const importable = sinon
+    .stub(ChromeMigrationUtils, "getImportableLogins")
+    .resolves(["chrome"]);
+  const migrator = sinon
+    .stub(MigrationUtils, "getMigrator")
+    .resolves(gTestMigrator);
+
+  const doExperimentCleanup = await ExperimentFakes.enrollWithFeatureConfig({
+    featureId: "password-autocomplete",
+    value: { directMigrateSingleProfile: true },
+  });
+
+  // This makes the last autocomplete test *not* show import suggestions.
+  Services.prefs.setIntPref("signon.suggestImportCount", 3);
+
+  registerCleanupFunction(async () => {
+    await doExperimentCleanup();
+    debounce.restore();
+    importable.restore();
+    migrator.restore();
+    Services.prefs.clearUserPref("signon.suggestImportCount");
+  });
+});
+
+add_task(async function check_fluent_ids() {
+  await document.l10n.ready;
+  MozXULElement.insertFTLIfNeeded("toolkit/main-window/autocomplete.ftl");
+
+  const host = "testhost.com";
+  for (const browser of ChromeMigrationUtils.CONTEXTUAL_LOGIN_IMPORT_BROWSERS) {
+    const id = `autocomplete-import-logins-${browser}`;
+    const message = await document.l10n.formatValue(id, { host });
+    Assert.ok(
+      message.includes(`data-l10n-name="line1"`),
+      `${id} included line1`
+    );
+    Assert.ok(
+      message.includes(`data-l10n-name="line2"`),
+      `${id} included line2`
+    );
+    Assert.ok(message.includes(host), `${id} replaced host`);
+  }
+});
+
+/**
+ * Tests that if the user selects the password import suggestion from
+ * the autocomplete popup, and there is more than one profile available
+ * to import from, that the migration wizard opens to guide the user
+ * through importing those logins.
+ */
+add_task(async function import_suggestion_wizard() {
+  let wizardTab;
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "https://example.com" + DIRECTORY_PATH + "form_basic.html",
+    },
+    async function (browser) {
+      const popup = document.getElementById("PopupAutoComplete");
+      Assert.ok(popup, "Got popup");
+      await openACPopup(popup, browser, "#form-basic-username");
+
+      const importableItem = popup.querySelector(
+        `[originaltype="importableLogins"]`
+      );
+      Assert.ok(importableItem, "Got importable suggestion richlistitem");
+
+      await BrowserTestUtils.waitForCondition(
+        () => !importableItem.collapsed,
+        "Wait for importable suggestion to show"
+      );
+
+      // Pretend there's 2+ profiles to trigger the wizard.
+      gTestMigrator.profiles.length = 2;
+
+      info("Clicking on importable suggestion");
+      const wizardPromise = BrowserTestUtils.waitForMigrationWizard(window);
+
+      EventUtils.synthesizeMouseAtCenter(importableItem, {});
+
+      wizardTab = await wizardPromise;
+      Assert.ok(wizardTab, "Wizard opened");
+      Assert.equal(
+        gTestMigrator.migrate.callCount,
+        0,
+        "Direct migrate not used"
+      );
+
+      await closePopup(popup);
+    }
+  );
+
+  // Close the wizard tab in the end of the test. If we close the wizard when the tab
+  // is still opened, the username field will be focused again, which triggers another
+  // importable suggestion.
+  await BrowserTestUtils.removeTab(wizardTab);
+});
+
+add_task(async function import_suggestion_learn_more() {
+  let supportTab;
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "https://example.com" + DIRECTORY_PATH + "form_basic.html",
+    },
+    async function (browser) {
+      const popup = document.getElementById("PopupAutoComplete");
+      Assert.ok(popup, "Got popup");
+      await openACPopup(popup, browser, "#form-basic-username");
+
+      const learnMoreItem = popup.querySelector(`[type="importableLearnMore"]`);
+      Assert.ok(learnMoreItem, "Got importable learn more richlistitem");
+
+      await BrowserTestUtils.waitForCondition(
+        () => !learnMoreItem.collapsed,
+        "Wait for importable learn more to show"
+      );
+
+      info("Clicking on importable learn more");
+      const supportTabPromise = BrowserTestUtils.waitForNewTab(
+        gBrowser,
+        Services.urlFormatter.formatURLPref("app.support.baseURL") +
+          "password-import"
+      );
+      EventUtils.synthesizeMouseAtCenter(learnMoreItem, {});
+      supportTab = await supportTabPromise;
+      Assert.ok(supportTab, "Support tab opened");
+
+      await closePopup(popup);
+    }
+  );
+
+  // Close the tab in the end of the test to avoid the username field being
+  // focused again.
+  await BrowserTestUtils.removeTab(supportTab);
+});
+
+add_task(async function import_suggestion_migrate() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "https://example.com" + DIRECTORY_PATH + "form_basic.html",
+    },
+    async function (browser) {
+      const popup = document.getElementById("PopupAutoComplete");
+      Assert.ok(popup, "Got popup");
+      await openACPopup(popup, browser, "#form-basic-username");
+
+      const importableItem = popup.querySelector(
+        `[originaltype="importableLogins"]`
+      );
+      Assert.ok(importableItem, "Got importable suggestion richlistitem");
+
+      await BrowserTestUtils.waitForCondition(
+        () => !importableItem.collapsed,
+        "Wait for importable suggestion to show"
+      );
+
+      // Pretend there's 1 profile to trigger migrate.
+      gTestMigrator.profiles.length = 1;
+
+      info("Clicking on importable suggestion");
+      const migratePromise = BrowserTestUtils.waitForCondition(
+        () => gTestMigrator.migrate.callCount,
+        "Wait for direct migration attempt"
+      );
+      EventUtils.synthesizeMouseAtCenter(importableItem, {});
+
+      const callCount = await migratePromise;
+      Assert.equal(callCount, 1, "Direct migrate used once");
+
+      const importedItem = await BrowserTestUtils.waitForCondition(
+        () => popup.querySelector(`[originaltype="loginWithOrigin"]`),
+        "Wait for imported login to show"
+      );
+      EventUtils.synthesizeMouseAtCenter(importedItem, {});
+
+      const username = await SpecialPowers.spawn(
+        browser,
+        [],
+        () => content.document.getElementById("form-basic-username").value
+      );
+      Assert.equal(username, "import", "username from import filled in");
+
+      LoginTestUtils.clearData();
+    }
+  );
+});
+
+add_task(async function import_suggestion_not_shown() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "https://example.com" + DIRECTORY_PATH + "form_basic.html",
+    },
+    async function (browser) {
+      const popup = document.getElementById("PopupAutoComplete");
+      Assert.ok(popup, "Got popup");
+      let opened = false;
+      openACPopup(popup, browser, "#form-basic-password").then(
+        () => (opened = true)
+      );
+
+      await TestUtils.waitForCondition(() => {
+        EventUtils.synthesizeKey("KEY_ArrowDown");
+        return opened;
+      });
+
+      const footer = popup.querySelector(`[originaltype="loginsFooter"]`);
+      Assert.ok(footer, "Got footer richlistitem");
+
+      await TestUtils.waitForCondition(() => {
+        return !EventUtils.isHidden(footer);
+      }, "Waiting for footer to become visible");
+
+      Assert.ok(
+        !popup.querySelector(`[originaltype="importableLogins"]`),
+        "No importable suggestion shown"
+      );
+
+      await closePopup(popup);
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_autocomplete_insecure_warning.js b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_insecure_warning.js
new file mode 100644
index 0000000000..f00ea80937
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_insecure_warning.js
@@ -0,0 +1,44 @@
+"use strict";
+
+const EXPECTED_SUPPORT_URL =
+  Services.urlFormatter.formatURLPref("app.support.baseURL") +
+  "insecure-password";
+
+add_task(async function test_clickInsecureFieldWarning() {
+  let url =
+    "https://example.com" +
+    DIRECTORY_PATH +
+    "form_cross_origin_insecure_action.html";
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function (browser) {
+      let popup = document.getElementById("PopupAutoComplete");
+      Assert.ok(popup, "Got popup");
+      await openACPopup(popup, browser, "#form-basic-username");
+      await new Promise(requestAnimationFrame);
+
+      let warningItem = popup.querySelector(`[type="insecureWarning"]`);
+      Assert.ok(warningItem, "Got warning richlistitem");
+
+      await BrowserTestUtils.waitForCondition(
+        () => !warningItem.collapsed,
+        "Wait for warning to show"
+      );
+
+      info("Clicking on warning");
+      let supportTabPromise = BrowserTestUtils.waitForNewTab(
+        gBrowser,
+        EXPECTED_SUPPORT_URL
+      );
+      EventUtils.synthesizeMouseAtCenter(warningItem, {});
+      let supportTab = await supportTabPromise;
+      Assert.ok(supportTab, "Support tab opened");
+      await closePopup(popup);
+      BrowserTestUtils.removeTab(supportTab);
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_autocomplete_primary_password.js b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_primary_password.js
new file mode 100644
index 0000000000..c3152740cd
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_autocomplete_primary_password.js
@@ -0,0 +1,121 @@
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
+const HOST = "https://example.com";
+const URL =
+  HOST + "/browser/toolkit/components/passwordmgr/test/browser/form_basic.html";
+const TIMEOUT_PREF = "signon.masterPasswordReprompt.timeout_ms";
+
+const BRAND_BUNDLE = Services.strings.createBundle(
+  "chrome://branding/locale/brand.properties"
+);
+const BRAND_FULL_NAME = BRAND_BUNDLE.GetStringFromName("brandFullName");
+
+// Waits for the primary password prompt and cancels it when close() is called on the return value.
+async function waitForDialog() {
+  let [subject] = await TestUtils.topicObserved("common-dialog-loaded");
+  let dialog = subject.Dialog;
+  let expected = "Password Required - " + BRAND_FULL_NAME;
+  Assert.equal(dialog.args.title, expected, "Check common dialog title");
+  return {
+    async close(win = window) {
+      dialog.ui.button1.click();
+      return BrowserTestUtils.waitForEvent(win, "DOMModalDialogClosed");
+    },
+  };
+}
+
+add_setup(async function () {
+  let login = LoginTestUtils.testData.formLogin({
+    origin: "https://example.com",
+    formActionOrigin: "https://example.com",
+    username: "username",
+    password: "password",
+  });
+  await Services.logins.addLoginAsync(login);
+  LoginTestUtils.primaryPassword.enable();
+
+  registerCleanupFunction(function () {
+    LoginTestUtils.primaryPassword.disable();
+  });
+
+  // Set primary password prompt timeout to 3s.
+  // If this test goes intermittent, you likely have to increase this value.
+  await SpecialPowers.pushPrefEnv({ set: [[TIMEOUT_PREF, 3000]] });
+});
+
+// Test that autocomplete does not trigger a primary password prompt
+// for a certain time after it was cancelled.
+add_task(async function test_mpAutocompleteTimeout() {
+  // Wait for initial primary password dialog after opening the tab.
+  let dialogShown = waitForDialog();
+
+  await BrowserTestUtils.withNewTab(URL, async function (browser) {
+    (await dialogShown).close();
+
+    await SpecialPowers.spawn(browser, [], async function () {
+      // Focus the password field to trigger autocompletion.
+      content.document.getElementById("form-basic-password").focus();
+    });
+
+    // Wait 4s, dialog should not have been shown
+    // (otherwise the code below will not work).
+    await new Promise(c => setTimeout(c, 4000));
+
+    dialogShown = waitForDialog();
+    await SpecialPowers.spawn(browser, [], async function () {
+      // Re-focus the password field to trigger autocompletion.
+      content.document.getElementById("form-basic-username").focus();
+      content.document.getElementById("form-basic-password").focus();
+    });
+    (await dialogShown).close();
+    closePopup(document.getElementById("PopupAutoComplete"));
+  });
+
+  // Wait 4s for the timer to pass again and not interfere with the next test.
+  await new Promise(c => setTimeout(c, 4000));
+});
+
+// Test that autocomplete does not trigger a primary password prompt
+// if one is already showing.
+add_task(async function test_mpAutocompleteUIBusy() {
+  // Wait for initial primary password dialog after adding the login.
+  let dialogShown = waitForDialog();
+
+  let win = await BrowserTestUtils.openNewBrowserWindow();
+
+  Services.tm.dispatchToMainThread(async () => {
+    try {
+      // Trigger a MP prompt in the new window by saving a login
+      await Services.logins.addLoginAsync(LoginTestUtils.testData.formLogin());
+    } catch (e) {
+      // Handle throwing from MP cancellation
+    }
+  });
+  let { close } = await dialogShown;
+
+  let windowGlobal =
+    gBrowser.selectedBrowser.browsingContext.currentWindowGlobal;
+  let loginManagerParent = windowGlobal.getActor("LoginManager");
+  let origin = "https://www.example.com";
+  let data = {
+    actionOrigin: "",
+    searchString: "",
+    previousResult: null,
+    hasBeenTypePassword: true,
+    isSecure: false,
+    isProbablyANewPasswordField: true,
+  };
+
+  function dialogObserver(subject, topic, data) {
+    Assert.ok(false, "A second dialog shouldn't have been shown");
+    Services.obs.removeObserver(dialogObserver, topic);
+  }
+  Services.obs.addObserver(dialogObserver, "common-dialog-loaded");
+
+  let results = await loginManagerParent.doAutocompleteSearch(origin, data);
+  Assert.equal(results.logins.length, 0, "No results since uiBusy is true");
+  await close(win);
+
+  await BrowserTestUtils.closeWindow(win);
+
+  Services.obs.removeObserver(dialogObserver, "common-dialog-loaded");
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_autofill_hidden_document.js b/toolkit/components/passwordmgr/test/browser/browser_autofill_hidden_document.js
new file mode 100644
index 0000000000..14ef8860e8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_autofill_hidden_document.js
@@ -0,0 +1,205 @@
+Services.scriptloader.loadSubScript(
+  "chrome://mochitests/content/browser/browser/components/aboutlogins/tests/browser/head.js",
+  this
+);
+
+const TEST_URL_PATH = "/browser/toolkit/components/passwordmgr/test/browser/";
+const INITIAL_URL = `about:blank`;
+const FORM_URL = `https://example.org${TEST_URL_PATH}form_basic.html`;
+const FORMLESS_URL = `https://example.org${TEST_URL_PATH}formless_basic.html`;
+const FORM_MULTIPAGE_URL = `https://example.org${TEST_URL_PATH}form_multipage.html`;
+const testUrls = [FORM_URL, FORMLESS_URL, FORM_MULTIPAGE_URL];
+const testUrlsWithForm = [FORM_URL, FORM_MULTIPAGE_URL];
+const BRAND_BUNDLE = Services.strings.createBundle(
+  "chrome://branding/locale/brand.properties"
+);
+const BRAND_FULL_NAME = BRAND_BUNDLE.GetStringFromName("brandFullName");
+
+async function getDocumentVisibilityState(browser) {
+  let visibility = await SpecialPowers.spawn(browser, [], async function () {
+    return content.document.visibilityState;
+  });
+  return visibility;
+}
+
+add_setup(async function () {
+  Services.prefs.setBoolPref("signon.usernameOnlyForm.enabled", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.usernameOnlyForm.enabled");
+  });
+
+  Services.logins.removeAllUserFacingLogins();
+  let login = LoginTestUtils.testData.formLogin({
+    origin: "https://example.org",
+    formActionOrigin: "https://example.org",
+    username: "user1",
+    password: "pass1",
+  });
+  await Services.logins.addLoginAsync(login);
+});
+
+testUrlsWithForm.forEach(testUrl => {
+  add_task(async function test_processed_form_fired() {
+    // Sanity check. If this doesnt work any results for the subsequent tasks are suspect
+    const tab1 = await BrowserTestUtils.openNewForegroundTab(
+      gBrowser,
+      INITIAL_URL
+    );
+    let tab1Visibility = await getDocumentVisibilityState(tab1.linkedBrowser);
+    Assert.equal(
+      tab1Visibility,
+      "visible",
+      "The first tab should be foreground"
+    );
+
+    let formProcessedPromise = listenForTestNotification("FormProcessed");
+    BrowserTestUtils.startLoadingURIString(tab1.linkedBrowser, testUrl);
+    await formProcessedPromise;
+    gBrowser.removeTab(tab1);
+  });
+});
+
+testUrls.forEach(testUrl => {
+  add_task(async function test_defer_autofill_until_visible() {
+    let result, tab1Visibility;
+    // open 2 tabs
+    const tab1 = await BrowserTestUtils.openNewForegroundTab(
+      gBrowser,
+      INITIAL_URL
+    );
+    const tab2 = await BrowserTestUtils.openNewForegroundTab(
+      gBrowser,
+      INITIAL_URL
+    );
+
+    // confirm document is hidden
+    tab1Visibility = await getDocumentVisibilityState(tab1.linkedBrowser);
+    Assert.equal(
+      tab1Visibility,
+      "hidden",
+      "The first tab should be backgrounded"
+    );
+
+    // we shouldn't even try to autofill while hidden, so wait for the document to be in the
+    // non-visible pending queue instead.
+    let formFilled = false;
+    listenForTestNotification("FormProcessed").then(() => {
+      formFilled = true;
+    });
+    BrowserTestUtils.startLoadingURIString(tab1.linkedBrowser, testUrl);
+
+    await TestUtils.waitForCondition(() => {
+      let windowGlobal = tab1.linkedBrowser.browsingContext.currentWindowGlobal;
+      if (!windowGlobal || windowGlobal.documentURI.spec == "about:blank") {
+        return false;
+      }
+
+      let actor = windowGlobal.getActor("LoginManager");
+      return actor.sendQuery("PasswordManager:formIsPending");
+    });
+
+    Assert.ok(
+      !formFilled,
+      "Observer should not be notified when form is loaded into a hidden document"
+    );
+
+    // Add the observer before switching tab
+    let formProcessedPromise = listenForTestNotification("FormProcessed");
+    await BrowserTestUtils.switchTab(gBrowser, tab1);
+    result = await formProcessedPromise;
+    tab1Visibility = await getDocumentVisibilityState(tab1.linkedBrowser);
+    Assert.equal(
+      tab1Visibility,
+      "visible",
+      "The first tab should be foreground"
+    );
+    Assert.ok(
+      result,
+      "Observer should be notified when input's document becomes visible"
+    );
+
+    // the form should have been autofilled with the login
+    let fieldValues = await SpecialPowers.spawn(
+      tab1.linkedBrowser,
+      [],
+      function () {
+        let doc = content.document;
+        return {
+          username: doc.getElementById("form-basic-username").value,
+          password: doc.getElementById("form-basic-password")?.value,
+        };
+      }
+    );
+    Assert.equal(fieldValues.username, "user1", "Checking filled username");
+
+    // skip password test for a username-only form
+    if (![FORM_MULTIPAGE_URL].includes(testUrl)) {
+      Assert.equal(fieldValues.password, "pass1", "Checking filled password");
+    }
+
+    gBrowser.removeTab(tab1);
+    gBrowser.removeTab(tab2);
+  });
+});
+
+testUrlsWithForm.forEach(testUrl => {
+  add_task(async function test_immediate_autofill_with_primarypassword() {
+    LoginTestUtils.primaryPassword.enable();
+    await LoginTestUtils.reloadData();
+    info(
+      `Have enabled primaryPassword, now isLoggedIn? ${Services.logins.isLoggedIn}`
+    );
+
+    registerCleanupFunction(async function () {
+      LoginTestUtils.primaryPassword.disable();
+      await LoginTestUtils.reloadData();
+    });
+
+    // open 2 tabs
+    const tab1 = await BrowserTestUtils.openNewForegroundTab(
+      gBrowser,
+      INITIAL_URL
+    );
+    const tab2 = await BrowserTestUtils.openNewForegroundTab(
+      gBrowser,
+      INITIAL_URL
+    );
+
+    info(
+      "load a background login form tab with a matching saved login " +
+        "and wait to see if the primary password dialog is shown"
+    );
+    Assert.equal(
+      await getDocumentVisibilityState(tab2.linkedBrowser),
+      "visible",
+      "The second tab should be visible"
+    );
+
+    const tab1Visibility = await getDocumentVisibilityState(tab1.linkedBrowser);
+    Assert.equal(
+      tab1Visibility,
+      "hidden",
+      "The first tab should be backgrounded"
+    );
+
+    const dialogObserved = waitForMPDialog("authenticate", tab1.ownerGlobal);
+
+    // In this case we will try to autofill while hidden, so look for the passwordmgr-processed-form
+    // to be observed
+    let formProcessedPromise = listenForTestNotification("FormProcessed");
+    BrowserTestUtils.startLoadingURIString(tab1.linkedBrowser, testUrl);
+    await Promise.all([formProcessedPromise, dialogObserved]);
+
+    Assert.ok(
+      formProcessedPromise,
+      "Observer should be notified when form is loaded into a hidden document"
+    );
+    Assert.ok(
+      dialogObserved,
+      "MP Dialog should be shown when form is loaded into a hidden document"
+    );
+
+    gBrowser.removeTab(tab1);
+    gBrowser.removeTab(tab2);
+  });
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_autofill_http.js b/toolkit/components/passwordmgr/test/browser/browser_autofill_http.js
new file mode 100644
index 0000000000..df80693673
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_autofill_http.js
@@ -0,0 +1,135 @@
+const TEST_URL_PATH =
+  "://example.org/browser/toolkit/components/passwordmgr/test/browser/";
+
+add_setup(async function () {
+  const login1 = LoginTestUtils.testData.formLogin({
+    origin: "http://example.org",
+    formActionOrigin: "http://example.org",
+    username: "username",
+    password: "password",
+  });
+  const login2 = LoginTestUtils.testData.formLogin({
+    origin: "http://example.org",
+    formActionOrigin: "http://example.com",
+    username: "username",
+    password: "password",
+  });
+  await Services.logins.addLogins([login1, login2]);
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.autofillForms.http", false]],
+  });
+});
+
+add_task(async function test_http_autofill() {
+  for (let scheme of ["http", "https"]) {
+    let formFilled = listenForTestNotification("FormProcessed");
+
+    let tab = await BrowserTestUtils.openNewForegroundTab(
+      gBrowser,
+      `${scheme}${TEST_URL_PATH}form_basic.html`
+    );
+
+    await formFilled;
+
+    let [username, password] = await SpecialPowers.spawn(
+      gBrowser.selectedBrowser,
+      [],
+      async function () {
+        let doc = content.document;
+        let contentUsername = doc.getElementById("form-basic-username").value;
+        let contentPassword = doc.getElementById("form-basic-password").value;
+        return [contentUsername, contentPassword];
+      }
+    );
+
+    Assert.equal(
+      username,
+      scheme == "http" ? "" : "username",
+      "Username filled correctly"
+    );
+    Assert.equal(
+      password,
+      scheme == "http" ? "" : "password",
+      "Password filled correctly"
+    );
+
+    gBrowser.removeTab(tab);
+  }
+});
+
+add_task(async function test_iframe_in_http_autofill() {
+  for (let scheme of ["http", "https"]) {
+    // Wait for parent and child iframe to be processed.
+    let formFilled = listenForTestNotification("FormProcessed", 2);
+
+    let tab = await BrowserTestUtils.openNewForegroundTab(
+      gBrowser,
+      `${scheme}${TEST_URL_PATH}form_basic_iframe.html`
+    );
+
+    await formFilled;
+
+    let [username, password] = await SpecialPowers.spawn(
+      gBrowser.selectedBrowser.browsingContext.children[0],
+      [],
+      async function () {
+        let doc = this.content.document;
+        return [
+          doc.getElementById("form-basic-username").value,
+          doc.getElementById("form-basic-password").value,
+        ];
+      }
+    );
+
+    Assert.equal(
+      username,
+      scheme == "http" ? "" : "username",
+      "Username filled correctly"
+    );
+    Assert.equal(
+      password,
+      scheme == "http" ? "" : "password",
+      "Password filled correctly"
+    );
+
+    gBrowser.removeTab(tab);
+  }
+});
+
+add_task(async function test_http_action_autofill() {
+  for (let type of ["insecure", "secure"]) {
+    let formFilled = listenForTestNotification("FormProcessed");
+
+    let tab = await BrowserTestUtils.openNewForegroundTab(
+      gBrowser,
+      `https${TEST_URL_PATH}form_cross_origin_${type}_action.html`
+    );
+
+    await formFilled;
+
+    let [username, password] = await SpecialPowers.spawn(
+      gBrowser.selectedBrowser,
+      [],
+      async function () {
+        let doc = this.content.document;
+        return [
+          doc.getElementById("form-basic-username").value,
+          doc.getElementById("form-basic-password").value,
+        ];
+      }
+    );
+
+    Assert.equal(
+      username,
+      type == "insecure" ? "" : "username",
+      "Username filled correctly"
+    );
+    Assert.equal(
+      password,
+      type == "insecure" ? "" : "password",
+      "Password filled correctly"
+    );
+
+    gBrowser.removeTab(tab);
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_autofill_track_filled_logins.js b/toolkit/components/passwordmgr/test/browser/browser_autofill_track_filled_logins.js
new file mode 100644
index 0000000000..8f5c2e3f45
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_autofill_track_filled_logins.js
@@ -0,0 +1,111 @@
+"use strict";
+
+const TEST_HOSTNAME = "https://example.com";
+const BASIC_FORM_PAGE_PATH = DIRECTORY_PATH + "form_basic.html";
+const BASIC_FORM_NO_USERNAME_PAGE_PATH =
+  DIRECTORY_PATH + "form_basic_no_username.html";
+
+add_task(async function test() {
+  let nsLoginInfo = new Components.Constructor(
+    "@mozilla.org/login-manager/loginInfo;1",
+    Ci.nsILoginInfo,
+    "init"
+  );
+  for (let usernameRequested of [true, false]) {
+    info(
+      "Testing page with " +
+        (usernameRequested ? "" : "no ") +
+        "username requested"
+    );
+    let url = usernameRequested
+      ? TEST_HOSTNAME + BASIC_FORM_PAGE_PATH
+      : TEST_HOSTNAME + BASIC_FORM_NO_USERNAME_PAGE_PATH;
+
+    // The login here must be a different domain than the page for this testcase.
+    let login = new nsLoginInfo(
+      "https://example.org",
+      "https://example.org",
+      null,
+      "bob",
+      "mypassword",
+      "form-basic-username",
+      "form-basic-password"
+    );
+    login = await Services.logins.addLoginAsync(login);
+    Assert.equal(
+      login.timesUsed,
+      1,
+      "The timesUsed should be 1 after creation"
+    );
+
+    let tab = await BrowserTestUtils.openNewForegroundTab({
+      gBrowser,
+      url,
+    });
+
+    // Convert the login object to a plain JS object for passing across process boundaries.
+    login = LoginHelper.loginToVanillaObject(login);
+    await SpecialPowers.spawn(
+      tab.linkedBrowser,
+      [{ login, usernameRequested }],
+      async ({ login: addedLogin, usernameRequested: aUsernameRequested }) => {
+        const { LoginFormFactory } = ChromeUtils.importESModule(
+          "resource://gre/modules/LoginFormFactory.sys.mjs"
+        );
+        const { LoginManagerChild } = ChromeUtils.importESModule(
+          "resource://gre/modules/LoginManagerChild.sys.mjs"
+        );
+        const { LoginHelper } = ChromeUtils.importESModule(
+          "resource://gre/modules/LoginHelper.sys.mjs"
+        );
+
+        let password = content.document.querySelector("#form-basic-password");
+        let formLike = LoginFormFactory.createFromField(password);
+        info("Calling _fillForm with FormLike");
+        addedLogin = LoginHelper.vanillaObjectToLogin(addedLogin);
+        LoginManagerChild.forWindow(content)._fillForm(
+          formLike,
+          [addedLogin],
+          null,
+          {
+            autofillForm: true,
+            clobberUsername: true,
+            clobberPassword: true,
+            userTriggered: true,
+          }
+        );
+
+        if (aUsernameRequested) {
+          let username = content.document.querySelector("#form-basic-username");
+          Assert.equal(username.value, "bob", "Filled username should match");
+        }
+        Assert.equal(
+          password.value,
+          "mypassword",
+          "Filled password should match"
+        );
+      }
+    );
+
+    let processedPromise = listenForTestNotification("ShowDoorhanger");
+    SpecialPowers.spawn(tab.linkedBrowser, [], () => {
+      content.document.getElementById("form-basic").submit();
+    });
+    await processedPromise;
+
+    let logins = await Services.logins.getAllLogins();
+
+    Assert.equal(logins.length, 1, "There should only be one login saved");
+    Assert.equal(
+      logins[0].guid,
+      login.guid,
+      "The saved login should match the one added and used above"
+    );
+    await checkOnlyLoginWasUsedTwice({ justChanged: false });
+
+    BrowserTestUtils.removeTab(tab);
+
+    // Reset all passwords before next iteration.
+    Services.logins.removeAllUserFacingLogins();
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_basicAuth_multiTab.js b/toolkit/components/passwordmgr/test/browser/browser_basicAuth_multiTab.js
new file mode 100644
index 0000000000..0069c653a5
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_basicAuth_multiTab.js
@@ -0,0 +1,158 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+/**
+ * Tests that can show multiple auth prompts in different tabs and handle them
+ * correctly.
+ */
+
+const ORIGIN1 = "https://example.com";
+const ORIGIN2 = "https://example.org";
+
+const AUTH_PATH =
+  "/browser/toolkit/components/passwordmgr/test/browser/authenticate.sjs";
+
+/**
+ * Opens a tab and navigates to the auth test path.
+ * @param {String} origin - Origin to open with test path.
+ * @param {Object} authOptions - Authentication options to pass to server and
+ * test for.
+ * @param {String} authOptions.user - Expected username.
+ * @param {String} authOptions.pass - Expected password.
+ * @param {String} authOptions.realm - Realm to return on auth request.
+ * @returns {Object} - An object containing passed origin and authOptions,
+ * opened tab, a promise which resolves once the tab loads, a promise which
+ * resolves once the prompt has been opened.
+ */
+async function openTabWithAuthPrompt(origin, authOptions) {
+  let tab = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    "https://example.com"
+  );
+
+  let promptPromise = PromptTestUtils.waitForPrompt(tab.linkedBrowser, {
+    modalType: Services.prompt.MODAL_TYPE_TAB,
+    promptType: "promptUserAndPass",
+  });
+  let url = new URL(origin + AUTH_PATH);
+  Object.entries(authOptions).forEach(([key, value]) =>
+    url.searchParams.append(key, value)
+  );
+  let loadPromise = BrowserTestUtils.browserLoaded(
+    tab.linkedBrowser,
+    false,
+    url.toString()
+  );
+  info("Loading " + url.toString());
+  BrowserTestUtils.startLoadingURIString(tab.linkedBrowser, url.toString());
+  return { origin, tab, authOptions, loadPromise, promptPromise };
+}
+
+/**
+ * Waits for tab to load and tests for expected auth state.
+ * @param {boolean} expectAuthed - true: auth success, false otherwise.
+ * @param {Object} tabInfo - Information about the tab as generated by
+ * openTabWithAuthPrompt.
+ */
+async function testTabAuthed(expectAuthed, { tab, loadPromise, authOptions }) {
+  // Wait for tab to load after auth.
+  await loadPromise;
+  Assert.ok(true, "Tab loads after auth");
+
+  // Fetch auth results from body (set by authenticate.sjs).
+  let { loginResult, user, pass } = await SpecialPowers.spawn(
+    tab.linkedBrowser,
+    [],
+    () => {
+      let result = {};
+      result.loginResult = content.document.getElementById("ok").innerText;
+      result.user = content.document.getElementById("user").innerText;
+      result.pass = content.document.getElementById("pass").innerText;
+      return result;
+    }
+  );
+
+  Assert.equal(
+    loginResult == "PASS",
+    expectAuthed,
+    "Site has expected auth state"
+  );
+  Assert.equal(user, expectAuthed ? authOptions.user : "", "Sent correct user");
+  Assert.equal(
+    pass,
+    expectAuthed ? authOptions.pass : "",
+    "Sent correct password"
+  );
+}
+
+add_setup(async function () {
+  await SpecialPowers.pushPrefEnv({
+    // This test relies on tab auth prompts.
+    set: [["prompts.modalType.httpAuth", Services.prompt.MODAL_TYPE_TAB]],
+  });
+});
+
+add_task(async function test() {
+  let tabA = await openTabWithAuthPrompt(ORIGIN1, {
+    user: "userA",
+    pass: "passA",
+    realm: "realmA",
+  });
+  // Tab B and C share realm and credentials.
+  // However, since the auth happens in separate tabs we should get two prompts.
+  let tabB = await openTabWithAuthPrompt(ORIGIN2, {
+    user: "userB",
+    pass: "passB",
+    realm: "realmB",
+  });
+  let tabC = await openTabWithAuthPrompt(ORIGIN2, {
+    user: "userB",
+    pass: "passB",
+    realm: "realmB",
+  });
+  let tabs = [tabA, tabB, tabC];
+
+  info(`Opening ${tabs.length} tabs with auth prompts`);
+  let prompts = await Promise.all(tabs.map(tab => tab.promptPromise));
+
+  Assert.equal(prompts.length, tabs.length, "Should have one prompt per tab");
+
+  for (let i = 0; i < prompts.length; i++) {
+    let titleEl = prompts[i].ui.prompt.document.querySelector("#titleText");
+    Assert.equal(
+      titleEl.textContent,
+      new URL(tabs[i].origin).host,
+      "Prompt matches the tab's host"
+    );
+  }
+
+  // Interact with the prompts. This is deliberately done out of order
+  // (no FIFO, LIFO).
+  let [promptA, promptB, promptC] = prompts;
+
+  // Accept prompt B with correct login details.
+  await PromptTestUtils.handlePrompt(promptB, {
+    loginInput: tabB.authOptions.user,
+    passwordInput: tabB.authOptions.pass,
+  });
+  await testTabAuthed(true, tabB);
+
+  // Accept prompt A with correct login details
+  await PromptTestUtils.handlePrompt(promptA, {
+    loginInput: tabA.authOptions.user,
+    passwordInput: tabA.authOptions.pass,
+  });
+  await testTabAuthed(true, tabA);
+
+  // Cancel prompt C
+  await PromptTestUtils.handlePrompt(promptC, {
+    buttonNumClick: 1,
+  });
+  await testTabAuthed(false, tabC);
+
+  // Cleanup tabs
+  tabs.forEach(({ tab }) => BrowserTestUtils.removeTab(tab));
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_basicAuth_rateLimit.js b/toolkit/components/passwordmgr/test/browser/browser_basicAuth_rateLimit.js
new file mode 100644
index 0000000000..1c12a8fec5
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_basicAuth_rateLimit.js
@@ -0,0 +1,146 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// This tests that the basic auth dialog can not be used for DOS attacks
+// and that the protections are reset on user-initiated navigation/reload.
+
+let promptModalType = Services.prefs.getIntPref("prompts.modalType.httpAuth");
+
+function promiseAuthWindowShown() {
+  return PromptTestUtils.handleNextPrompt(
+    window,
+    { modalType: promptModalType, promptType: "promptUserAndPass" },
+    { buttonNumClick: 1 }
+  );
+}
+
+add_task(async function test() {
+  await BrowserTestUtils.withNewTab(
+    "https://example.com",
+    async function (browser) {
+      let cancelDialogLimit = Services.prefs.getIntPref(
+        "prompts.authentication_dialog_abuse_limit"
+      );
+
+      let authShown = promiseAuthWindowShown();
+      let browserLoaded = BrowserTestUtils.browserLoaded(browser);
+      BrowserTestUtils.startLoadingURIString(
+        browser,
+        "https://example.com/browser/toolkit/components/passwordmgr/test/browser/authenticate.sjs"
+      );
+      await authShown;
+      Assert.ok(true, "Seen dialog number 1");
+      await browserLoaded;
+      Assert.ok(true, "Loaded document number 1");
+
+      // Reload the document a bit more often than should be allowed.
+      // As long as we're in the acceptable range we should receive
+      // auth prompts, otherwise we should not receive them and the
+      // page should just load.
+      // We've already seen the dialog once, hence we start the loop at 1.
+      for (let i = 1; i < cancelDialogLimit + 2; i++) {
+        if (i < cancelDialogLimit) {
+          authShown = promiseAuthWindowShown();
+        }
+        browserLoaded = BrowserTestUtils.browserLoaded(browser);
+        SpecialPowers.spawn(browser, [], function () {
+          content.document.location.reload();
+        });
+        if (i < cancelDialogLimit) {
+          await authShown;
+          Assert.ok(true, `Seen dialog number ${i + 1}`);
+        }
+        await browserLoaded;
+        Assert.ok(true, `Loaded document number ${i + 1}`);
+      }
+
+      let reloadButton = document.getElementById("reload-button");
+      await TestUtils.waitForCondition(
+        () => !reloadButton.hasAttribute("disabled")
+      );
+
+      // Verify that we can click the reload button to reset the counter.
+      authShown = promiseAuthWindowShown();
+      browserLoaded = BrowserTestUtils.browserLoaded(browser);
+      reloadButton.click();
+      await authShown;
+      Assert.ok(true, "Seen dialog number 1");
+      await browserLoaded;
+      Assert.ok(true, "Loaded document number 1");
+
+      // Now check loading subresources with auth on the page.
+      browserLoaded = BrowserTestUtils.browserLoaded(browser);
+      BrowserTestUtils.startLoadingURIString(browser, "https://example.com");
+      await browserLoaded;
+
+      // We've already seen the dialog once, hence we start the loop at 1.
+      for (let i = 1; i < cancelDialogLimit + 2; i++) {
+        if (i < cancelDialogLimit) {
+          authShown = promiseAuthWindowShown();
+        }
+
+        let iframeLoaded = SpecialPowers.spawn(browser, [], async function () {
+          let doc = content.document;
+          let iframe = doc.createElement("iframe");
+          doc.body.appendChild(iframe);
+          let loaded = new Promise(resolve => {
+            iframe.addEventListener(
+              "load",
+              function (e) {
+                resolve();
+              },
+              { once: true }
+            );
+          });
+          iframe.src =
+            "https://example.com/browser/toolkit/components/passwordmgr/test/browser/authenticate.sjs";
+          await loaded;
+        });
+
+        if (i < cancelDialogLimit) {
+          await authShown;
+          Assert.ok(true, `Seen dialog number ${i + 1}`);
+        }
+
+        await iframeLoaded;
+        Assert.ok(true, `Loaded iframe number ${i + 1}`);
+      }
+
+      // Verify that third party subresources can not spawn new auth dialogs.
+      let iframeLoaded = SpecialPowers.spawn(browser, [], async function () {
+        let doc = content.document;
+        let iframe = doc.createElement("iframe");
+        doc.body.appendChild(iframe);
+        let loaded = new Promise(resolve => {
+          iframe.addEventListener(
+            "load",
+            function (e) {
+              resolve();
+            },
+            { once: true }
+          );
+        });
+        iframe.src =
+          "https://example.org/browser/toolkit/components/passwordmgr/test/browser/authenticate.sjs";
+        await loaded;
+      });
+
+      await iframeLoaded;
+      Assert.ok(
+        true,
+        "Loaded a third party iframe without showing the auth dialog"
+      );
+
+      // Verify that pressing enter in the urlbar also resets the counter.
+      authShown = promiseAuthWindowShown();
+      browserLoaded = BrowserTestUtils.browserLoaded(browser);
+      gURLBar.value =
+        "https://example.com/browser/toolkit/components/passwordmgr/test/browser/authenticate.sjs";
+      gURLBar.focus();
+      EventUtils.synthesizeKey("KEY_Enter");
+      await authShown;
+      await browserLoaded;
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_basicAuth_switchTab.js b/toolkit/components/passwordmgr/test/browser/browser_basicAuth_switchTab.js
new file mode 100644
index 0000000000..8fddea4c93
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_basicAuth_switchTab.js
@@ -0,0 +1,34 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+let modalType = Services.prefs.getIntPref("prompts.modalType.httpAuth");
+
+add_task(async function test() {
+  let tab = BrowserTestUtils.addTab(gBrowser);
+  isnot(tab, gBrowser.selectedTab, "New tab shouldn't be selected");
+
+  let authPromptShown = PromptTestUtils.waitForPrompt(tab.linkedBrowser, {
+    modalType,
+    promptType: "promptUserAndPass",
+  });
+
+  let loadPromise = BrowserTestUtils.browserLoaded(tab.linkedBrowser);
+  BrowserTestUtils.startLoadingURIString(
+    tab.linkedBrowser,
+    "https://example.com/browser/toolkit/components/passwordmgr/test/browser/authenticate.sjs"
+  );
+
+  // Wait for the basic auth prompt
+  let dialog = await authPromptShown;
+
+  Assert.equal(gBrowser.selectedTab, tab, "Should have selected the new tab");
+
+  // Cancel the auth prompt
+  PromptTestUtils.handlePrompt(dialog, { buttonNumClick: 1 });
+
+  // After closing the prompt the load should finish
+  await loadPromise;
+
+  gBrowser.removeTab(tab);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_context_menu.js b/toolkit/components/passwordmgr/test/browser/browser_context_menu.js
new file mode 100644
index 0000000000..5f97a91324
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_context_menu.js
@@ -0,0 +1,678 @@
+/**
+ * Test the password manager context menu.
+ */
+
+/* eslint no-shadow:"off" */
+
+"use strict";
+
+// The origin for the test URIs.
+const TEST_ORIGIN = "https://example.com";
+const MULTIPLE_FORMS_PAGE_PATH =
+  "/browser/toolkit/components/passwordmgr/test/browser/multiple_forms.html";
+
+const CONTEXT_MENU = document.getElementById("contentAreaContextMenu");
+const POPUP_HEADER = document.getElementById("fill-login");
+
+/**
+ * Initialize logins needed for the tests and disable autofill
+ * for login forms for easier testing of manual fill.
+ */
+add_task(async function test_initialize() {
+  Services.prefs.setBoolPref("signon.autofillForms", false);
+  Services.prefs.setBoolPref("signon.usernameOnlyForm.enabled", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.autofillForms");
+    Services.prefs.clearUserPref("signon.schemeUpgrades");
+    Services.prefs.clearUserPref("signon.usernameOnlyForm.enabled");
+  });
+  await Services.logins.addLogins(loginList());
+});
+
+/**
+ * Check if the context menu is populated with the right
+ * menuitems for the target password input field.
+ */
+add_task(async function test_context_menu_populate_password_noSchemeUpgrades() {
+  Services.prefs.setBoolPref("signon.schemeUpgrades", false);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + MULTIPLE_FORMS_PAGE_PATH,
+    },
+    async function (browser) {
+      await openPasswordContextMenu(browser, "#test-password-1");
+
+      // Check the content of the password manager popup
+      let popupMenu = document.getElementById("fill-login-popup");
+      checkMenu(popupMenu, 2);
+
+      await closePopup(CONTEXT_MENU);
+    }
+  );
+});
+
+/**
+ * Check if the context menu is populated with the right
+ * menuitems for the target password input field.
+ */
+add_task(async function test_context_menu_populate_password_schemeUpgrades() {
+  Services.prefs.setBoolPref("signon.schemeUpgrades", true);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + MULTIPLE_FORMS_PAGE_PATH,
+    },
+    async function (browser) {
+      await openPasswordContextMenu(browser, "#test-password-1");
+
+      // Check the content of the password manager popup
+      let popupMenu = document.getElementById("fill-login-popup");
+      checkMenu(popupMenu, 3);
+
+      await closePopup(CONTEXT_MENU);
+    }
+  );
+});
+
+/**
+ * Check if the context menu is populated with the right menuitems
+ * for the target username field with a password field present.
+ */
+add_task(
+  async function test_context_menu_populate_username_with_password_noSchemeUpgrades() {
+    Services.prefs.setBoolPref("signon.schemeUpgrades", false);
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url:
+          TEST_ORIGIN +
+          "/browser/toolkit/components/" +
+          "passwordmgr/test/browser/multiple_forms.html",
+      },
+      async function (browser) {
+        await openPasswordContextMenu(browser, "#test-username-3");
+
+        // Check the content of the password manager popup
+        let popupMenu = document.getElementById("fill-login-popup");
+        checkMenu(popupMenu, 2);
+
+        await closePopup(CONTEXT_MENU);
+      }
+    );
+  }
+);
+/**
+ * Check if the context menu is populated with the right menuitems
+ * for the target username field with a password field present.
+ */
+add_task(
+  async function test_context_menu_populate_username_with_password_schemeUpgrades() {
+    Services.prefs.setBoolPref("signon.schemeUpgrades", true);
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url:
+          TEST_ORIGIN +
+          "/browser/toolkit/components/" +
+          "passwordmgr/test/browser/multiple_forms.html",
+      },
+      async function (browser) {
+        await openPasswordContextMenu(browser, "#test-username-3");
+
+        // Check the content of the password manager popup
+        let popupMenu = document.getElementById("fill-login-popup");
+        checkMenu(popupMenu, 3);
+
+        await closePopup(CONTEXT_MENU);
+      }
+    );
+  }
+);
+
+/**
+ * Check if the context menu is populated with the right menuitems
+ * for the target username field without a password field present.
+ */
+add_task(
+  async function test_context_menu_populate_username_with_password_noSchemeUpgrades() {
+    Services.prefs.setBoolPref("signon.schemeUpgrades", false);
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url:
+          TEST_ORIGIN +
+          "/browser/toolkit/components/" +
+          "passwordmgr/test/browser/multiple_forms.html",
+      },
+      async function (browser) {
+        await openPasswordContextMenu(browser, "#test-username-1");
+
+        // Check the content of the password manager popup
+        let popupMenu = document.getElementById("fill-login-popup");
+        checkMenu(popupMenu, 2);
+
+        await closePopup(CONTEXT_MENU);
+      }
+    );
+  }
+);
+/**
+ * Check if the context menu is populated with the right menuitems
+ * for the target username field without a password field present.
+ */
+add_task(
+  async function test_context_menu_populate_username_with_password_schemeUpgrades() {
+    Services.prefs.setBoolPref("signon.schemeUpgrades", true);
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url:
+          TEST_ORIGIN +
+          "/browser/toolkit/components/" +
+          "passwordmgr/test/browser/multiple_forms.html",
+      },
+      async function (browser) {
+        await openPasswordContextMenu(browser, "#test-username-1");
+
+        // Check the content of the password manager popup
+        let popupMenu = document.getElementById("fill-login-popup");
+        checkMenu(popupMenu, 3);
+
+        await closePopup(CONTEXT_MENU);
+      }
+    );
+  }
+);
+
+/**
+ * Check if the password field is correctly filled when one
+ * login menuitem is clicked.
+ */
+add_task(async function test_context_menu_password_fill() {
+  Services.prefs.setBoolPref("signon.schemeUpgrades", true);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + MULTIPLE_FORMS_PAGE_PATH,
+    },
+    async function (browser) {
+      let formDescriptions = await SpecialPowers.spawn(
+        browser,
+        [],
+        async function () {
+          let forms = Array.from(
+            content.document.getElementsByClassName("test-form")
+          );
+          return forms.map(f => f.getAttribute("description"));
+        }
+      );
+
+      for (let description of formDescriptions) {
+        info("Testing form: " + description);
+
+        let passwordInputIds = await SpecialPowers.spawn(
+          browser,
+          [{ description }],
+          async function ({ description }) {
+            let formElement = content.document.querySelector(
+              `[description="${description}"]`
+            );
+            let passwords = Array.from(
+              formElement.querySelectorAll(
+                "input[type='password'], input[data-type='password']"
+              )
+            );
+            return passwords.map(p => p.id);
+          }
+        );
+
+        for (let inputId of passwordInputIds) {
+          info("Testing password field: " + inputId);
+
+          // Synthesize a right mouse click over the password input element.
+          await openPasswordContextMenu(
+            browser,
+            "#" + inputId,
+            async function () {
+              let inputDisabled = await SpecialPowers.spawn(
+                browser,
+                [{ inputId }],
+                async function ({ inputId }) {
+                  let input = content.document.getElementById(inputId);
+                  return input.disabled || input.readOnly;
+                }
+              );
+
+              // If the password field is disabled or read-only, we want to see
+              // the disabled Fill Password popup header.
+              if (inputDisabled) {
+                Assert.ok(!POPUP_HEADER.hidden, "Popup menu is not hidden.");
+                Assert.ok(POPUP_HEADER.disabled, "Popup menu is disabled.");
+                await closePopup(CONTEXT_MENU);
+              }
+              Assert.equal(
+                POPUP_HEADER.getAttribute("data-l10n-id"),
+                "main-context-menu-use-saved-password",
+                "top-level label is correct"
+              );
+
+              return !inputDisabled;
+            }
+          );
+
+          if (CONTEXT_MENU.state != "open") {
+            continue;
+          }
+
+          // The only field affected by the password fill
+          // should be the target password field itself.
+          await assertContextMenuFill(browser, description, null, inputId, 1);
+          await SpecialPowers.spawn(
+            browser,
+            [{ inputId }],
+            async function ({ inputId }) {
+              let passwordField = content.document.getElementById(inputId);
+              Assert.equal(
+                passwordField.value,
+                "password1",
+                "Check upgraded login was actually used"
+              );
+            }
+          );
+
+          await closePopup(CONTEXT_MENU);
+        }
+      }
+    }
+  );
+});
+
+/**
+ * Check if the form is correctly filled when one
+ * username context menu login menuitem is clicked.
+ */
+add_task(async function test_context_menu_username_login_fill() {
+  Services.prefs.setBoolPref("signon.schemeUpgrades", true);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + MULTIPLE_FORMS_PAGE_PATH,
+    },
+    async function (browser) {
+      let formDescriptions = await SpecialPowers.spawn(
+        browser,
+        [],
+        async function () {
+          let forms = Array.from(
+            content.document.getElementsByClassName("test-form")
+          );
+          return forms.map(f => f.getAttribute("description"));
+        }
+      );
+
+      for (let description of formDescriptions) {
+        info("Testing form: " + description);
+        let usernameInputIds = await SpecialPowers.spawn(
+          browser,
+          [{ description }],
+          async function ({ description }) {
+            let formElement = content.document.querySelector(
+              `[description="${description}"]`
+            );
+            let inputs = Array.from(
+              formElement.querySelectorAll(
+                "input[type='text']:not([data-type='password'])"
+              )
+            );
+            return inputs.map(p => p.id);
+          }
+        );
+
+        for (let inputId of usernameInputIds) {
+          info("Testing username field: " + inputId);
+
+          // Synthesize a right mouse click over the username input element.
+          await openPasswordContextMenu(
+            browser,
+            "#" + inputId,
+            async function () {
+              let headerHidden = POPUP_HEADER.hidden;
+              let headerDisabled = POPUP_HEADER.disabled;
+              let headerLabelID = POPUP_HEADER.getAttribute("data-l10n-id");
+
+              let data = {
+                description,
+                inputId,
+                headerHidden,
+                headerDisabled,
+                headerLabelID,
+              };
+              let shouldContinue = await SpecialPowers.spawn(
+                browser,
+                [data],
+                async function (data) {
+                  let {
+                    description,
+                    inputId,
+                    headerHidden,
+                    headerDisabled,
+                    headerLabelID,
+                  } = data;
+                  let formElement = content.document.querySelector(
+                    `[description="${description}"]`
+                  );
+                  let usernameField = content.document.getElementById(inputId);
+                  // We always want to check if the first password field is filled,
+                  // since this is the current behavior from the _fillForm function.
+                  let passwordField = formElement.querySelector(
+                    "input[type='password'], input[data-type='password']"
+                  );
+
+                  // If we don't want to see the actual popup menu,
+                  // check if the popup is hidden or disabled.
+                  if (
+                    !passwordField ||
+                    usernameField.disabled ||
+                    usernameField.readOnly ||
+                    passwordField.disabled ||
+                    passwordField.readOnly
+                  ) {
+                    if (!passwordField) {
+                      // Should show popup for a username-only form.
+                      if (usernameField.autocomplete == "username") {
+                        Assert.ok(!headerHidden, "Popup menu is not hidden.");
+                      } else {
+                        Assert.ok(headerHidden, "Popup menu is hidden.");
+                      }
+                    } else {
+                      Assert.ok(!headerHidden, "Popup menu is not hidden.");
+                      Assert.ok(headerDisabled, "Popup menu is disabled.");
+                    }
+                    return false;
+                  }
+                  Assert.equal(
+                    headerLabelID,
+                    "main-context-menu-use-saved-password",
+                    "top-level label is correct"
+                  );
+                  return true;
+                }
+              );
+
+              if (!shouldContinue) {
+                await closePopup(CONTEXT_MENU);
+              }
+
+              return shouldContinue;
+            }
+          );
+
+          if (CONTEXT_MENU.state != "open") {
+            continue;
+          }
+
+          let passwordFieldId = await SpecialPowers.spawn(
+            browser,
+            [{ description }],
+            async function ({ description }) {
+              let formElement = content.document.querySelector(
+                `[description="${description}"]`
+              );
+              return formElement.querySelector(
+                "input[type='password'], input[data-type='password']"
+              ).id;
+            }
+          );
+
+          // We shouldn't change any field that's not the target username field or the first password field
+          await assertContextMenuFill(
+            browser,
+            description,
+            inputId,
+            passwordFieldId,
+            1
+          );
+
+          await SpecialPowers.spawn(
+            browser,
+            [{ passwordFieldId }],
+            async function ({ passwordFieldId }) {
+              let passwordField =
+                content.document.getElementById(passwordFieldId);
+              if (!passwordField.hasAttribute("expectedFail")) {
+                Assert.equal(
+                  passwordField.value,
+                  "password1",
+                  "Check upgraded login was actually used"
+                );
+              }
+            }
+          );
+
+          await closePopup(CONTEXT_MENU);
+        }
+      }
+    }
+  );
+});
+
+/**
+ * Check event telemetry is correctly recorded when opening the saved logins / management UI
+ * from the context menu
+ */
+add_task(async function test_context_menu_open_management() {
+  Services.prefs.setBoolPref("signon.schemeUpgrades", false);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + MULTIPLE_FORMS_PAGE_PATH,
+    },
+    async function (browser) {
+      await openPasswordContextMenu(browser, "#test-password-1");
+
+      let openingFunc = () => gContextMenu.openPasswordManager();
+      // wait until the management UI opens
+      let passwordManager = await openPasswordManager(openingFunc);
+      info("Management UI dialog was opened");
+
+      TelemetryTestUtils.assertEvents(
+        [["pwmgr", "open_management", "contextmenu"]],
+        { category: "pwmgr", method: "open_management" },
+        { clear: true, process: "content" }
+      );
+
+      await passwordManager.close();
+      await closePopup(CONTEXT_MENU);
+    }
+  );
+});
+
+/**
+ * Verify that only the expected form fields are filled.
+ */
+async function assertContextMenuFill(
+  browser,
+  formId,
+  usernameFieldId,
+  passwordFieldId,
+  loginIndex
+) {
+  let popupMenu = document.getElementById("fill-login-popup");
+  let unchangedSelector = `[description="${formId}"] input:not(#${passwordFieldId})`;
+
+  if (usernameFieldId) {
+    unchangedSelector += `:not(#${usernameFieldId})`;
+  }
+
+  await SpecialPowers.spawn(
+    browser,
+    [{ unchangedSelector }],
+    async function ({ unchangedSelector }) {
+      let unchangedFields =
+        content.document.querySelectorAll(unchangedSelector);
+
+      // Store the value of fields that should remain unchanged.
+      if (unchangedFields.length) {
+        for (let field of unchangedFields) {
+          field.setAttribute("original-value", field.value);
+        }
+      }
+    }
+  );
+
+  // Execute the default command of the specified login menuitem found in the context menu.
+  let loginItem =
+    popupMenu.getElementsByClassName("context-login-item")[loginIndex];
+
+  // Find the used login by it's username (Use only unique usernames in this test).
+  let { username, password } = getLoginFromUsername(loginItem.label);
+
+  let data = {
+    username,
+    password,
+    usernameFieldId,
+    passwordFieldId,
+    formId,
+    unchangedSelector,
+  };
+  let continuePromise = ContentTask.spawn(browser, data, async function (data) {
+    let {
+      username,
+      password,
+      usernameFieldId,
+      passwordFieldId,
+      formId,
+      unchangedSelector,
+    } = data;
+    let form = content.document.querySelector(`[description="${formId}"]`);
+    await ContentTaskUtils.waitForEvent(
+      form,
+      "input",
+      "Username input value changed"
+    );
+
+    if (usernameFieldId) {
+      let usernameField = content.document.getElementById(usernameFieldId);
+
+      // If we have an username field, check if it's correctly filled
+      if (usernameField.getAttribute("expectedFail") == null) {
+        Assert.equal(
+          username,
+          usernameField.value,
+          "Username filled and correct."
+        );
+      }
+    }
+
+    if (passwordFieldId) {
+      let passwordField = content.document.getElementById(passwordFieldId);
+
+      // If we have a password field, check if it's correctly filled
+      if (passwordField && passwordField.getAttribute("expectedFail") == null) {
+        Assert.equal(
+          password,
+          passwordField.value,
+          "Password filled and correct."
+        );
+      }
+    }
+
+    let unchangedFields = content.document.querySelectorAll(unchangedSelector);
+
+    // Check that all fields that should not change have the same value as before.
+    if (unchangedFields.length) {
+      Assert.ok(() => {
+        for (let field of unchangedFields) {
+          if (field.value != field.getAttribute("original-value")) {
+            return false;
+          }
+        }
+        return true;
+      }, "Other fields were not changed.");
+    }
+  });
+
+  loginItem.doCommand();
+
+  return continuePromise;
+}
+
+/**
+ * Check if every login that matches the page origin are available at the context menu.
+ * @param {Element} contextMenu
+ * @param {Number} expectedCount - Number of logins expected in the context menu. Used to ensure
+ *                                  we continue testing something useful.
+ */
+function checkMenu(contextMenu, expectedCount) {
+  let logins = loginList().filter(login => {
+    return LoginHelper.isOriginMatching(login.origin, TEST_ORIGIN, {
+      schemeUpgrades: Services.prefs.getBoolPref("signon.schemeUpgrades"),
+    });
+  });
+  // Make an array of menuitems for easier comparison.
+  let menuitems = [
+    ...CONTEXT_MENU.getElementsByClassName("context-login-item"),
+  ];
+  Assert.equal(
+    menuitems.length,
+    expectedCount,
+    "Expected number of menu items"
+  );
+  Assert.ok(
+    logins.every(l => menuitems.some(m => l.username == m.label)),
+    "Every login have an item at the menu."
+  );
+}
+
+/**
+ * Search for a login by it's username.
+ *
+ * Only unique login/origin combinations should be used at this test.
+ */
+function getLoginFromUsername(username) {
+  return loginList().find(login => login.username == username);
+}
+
+/**
+ * List of logins used for the test.
+ *
+ * We should only use unique usernames in this test,
+ * because we need to search logins by username. There is one duplicate u+p combo
+ * in order to test de-duping in the menu.
+ */
+function loginList() {
+  return [
+    LoginTestUtils.testData.formLogin({
+      origin: "https://example.com",
+      formActionOrigin: "https://example.com",
+      username: "username",
+      password: "password",
+    }),
+    // Same as above but HTTP in order to test de-duping.
+    LoginTestUtils.testData.formLogin({
+      origin: "http://example.com",
+      formActionOrigin: "http://example.com",
+      username: "username",
+      password: "password",
+    }),
+    LoginTestUtils.testData.formLogin({
+      origin: "http://example.com",
+      formActionOrigin: "http://example.com",
+      username: "username1",
+      password: "password1",
+    }),
+    LoginTestUtils.testData.formLogin({
+      origin: "https://example.com",
+      formActionOrigin: "https://example.com",
+      username: "username2",
+      password: "password2",
+    }),
+    LoginTestUtils.testData.formLogin({
+      origin: "http://example.org",
+      formActionOrigin: "http://example.org",
+      username: "username-cross-origin",
+      password: "password-cross-origin",
+    }),
+  ];
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_context_menu_autocomplete_interaction.js b/toolkit/components/passwordmgr/test/browser/browser_context_menu_autocomplete_interaction.js
new file mode 100644
index 0000000000..8ffe07a673
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_context_menu_autocomplete_interaction.js
@@ -0,0 +1,120 @@
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
+/*
+ * Test the password manager context menu interaction with autocomplete.
+ */
+
+"use strict";
+
+const TEST_ORIGIN = "https://example.com";
+const BASIC_FORM_PAGE_PATH = DIRECTORY_PATH + "form_basic.html";
+
+/**
+ * Initialize logins needed for the tests and disable autofill
+ * for login forms for easier testing of manual fill.
+ */
+add_task(async function test_initialize() {
+  let autocompletePopup = document.getElementById("PopupAutoComplete");
+  Services.prefs.setBoolPref("signon.autofillForms", false);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.autofillForms");
+    autocompletePopup.removeEventListener(
+      "popupshowing",
+      autocompleteUnexpectedPopupShowing
+    );
+  });
+  await Services.logins.addLogins(loginList());
+  autocompletePopup.addEventListener(
+    "popupshowing",
+    autocompleteUnexpectedPopupShowing
+  );
+});
+
+add_task(async function test_context_menu_username() {
+  let formFilled = listenForTestNotification("FormProcessed");
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + BASIC_FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await formFilled;
+      await openContextMenu(browser, "#form-basic-username");
+
+      let contextMenu = document.getElementById("contentAreaContextMenu");
+      Assert.equal(contextMenu.state, "open", "Context menu opened");
+      contextMenu.hidePopup();
+    }
+  );
+});
+
+add_task(async function test_context_menu_password() {
+  let formFilled = listenForTestNotification("FormProcessed");
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + BASIC_FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await formFilled;
+      await openContextMenu(browser, "#form-basic-password");
+
+      let contextMenu = document.getElementById("contentAreaContextMenu");
+      Assert.equal(contextMenu.state, "open", "Context menu opened");
+      contextMenu.hidePopup();
+    }
+  );
+});
+
+function autocompleteUnexpectedPopupShowing(event) {
+  Assert.ok(false, "Autocomplete shouldn't appear");
+  event.target.hidePopup();
+}
+
+/**
+ * Synthesize mouse clicks to open the context menu popup
+ * for a target login input element.
+ */
+async function openContextMenu(browser, loginInput) {
+  // First synthesize a mousedown. We need this to get the focus event with the "contextmenu" event.
+  let eventDetails1 = { type: "mousedown", button: 2 };
+  await BrowserTestUtils.synthesizeMouseAtCenter(
+    loginInput,
+    eventDetails1,
+    browser
+  );
+
+  // Then synthesize the contextmenu click over the input element.
+  let contextMenuShownPromise = BrowserTestUtils.waitForEvent(
+    window,
+    "popupshown"
+  );
+  let eventDetails = { type: "contextmenu", button: 2 };
+  await BrowserTestUtils.synthesizeMouseAtCenter(
+    loginInput,
+    eventDetails,
+    browser
+  );
+  await contextMenuShownPromise;
+
+  // Wait to see which popups are shown.
+  await new Promise(resolve => setTimeout(resolve, 1000));
+}
+
+function loginList() {
+  return [
+    LoginTestUtils.testData.formLogin({
+      origin: "https://example.com",
+      formActionOrigin: "https://example.com",
+      username: "username",
+      password: "password",
+    }),
+    LoginTestUtils.testData.formLogin({
+      origin: "https://example.com",
+      formActionOrigin: "https://example.com",
+      username: "username2",
+      password: "password2",
+    }),
+  ];
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_context_menu_generated_password.js b/toolkit/components/passwordmgr/test/browser/browser_context_menu_generated_password.js
new file mode 100644
index 0000000000..41e99443c0
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_context_menu_generated_password.js
@@ -0,0 +1,482 @@
+/**
+ * Test the password manager context menu item can fill password fields with a generated password.
+ */
+
+/* eslint no-shadow:"off" */
+
+"use strict";
+
+// The origin for the test URIs.
+const TEST_ORIGIN = "https://example.com";
+const FORM_PAGE_PATH =
+  "/browser/toolkit/components/passwordmgr/test/browser/form_basic_login.html";
+const CONTEXT_MENU = document.getElementById("contentAreaContextMenu");
+
+const passwordInputSelector = "#form-basic-password";
+
+registerCleanupFunction(async function cleanup_resetPrefs() {
+  await SpecialPowers.popPrefEnv();
+});
+
+add_setup(async function () {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["signon.generation.available", true],
+      ["signon.generation.enabled", true],
+    ],
+  });
+  // assert that there are no logins
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 0, "There are no logins");
+});
+
+add_task(async function test_hidden_by_prefs() {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["signon.generation.available", true],
+      ["signon.generation.enabled", false],
+    ],
+  });
+
+  // test that the generated password option is not present when the feature is not enabled
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+      await openPasswordContextMenu(browser, passwordInputSelector);
+      let generatedPasswordItem = document.getElementById(
+        "fill-login-generated-password"
+      );
+      Assert.ok(
+        !BrowserTestUtils.isVisible(generatedPasswordItem),
+        "generated password item is hidden"
+      );
+
+      CONTEXT_MENU.hidePopup();
+    }
+  );
+  await SpecialPowers.popPrefEnv();
+});
+
+add_task(async function test_fill_hidden_by_login_saving_disabled() {
+  // test that the generated password option is not present when the user
+  // disabled password saving for the site.
+  Services.logins.setLoginSavingEnabled(TEST_ORIGIN, false);
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+      await openPasswordContextMenu(browser, passwordInputSelector);
+      let generatedPasswordItem = document.getElementById(
+        "fill-login-generated-password"
+      );
+      Assert.ok(
+        !BrowserTestUtils.isVisible(generatedPasswordItem),
+        "generated password item is hidden"
+      );
+
+      CONTEXT_MENU.hidePopup();
+    }
+  );
+
+  Services.logins.setLoginSavingEnabled(TEST_ORIGIN, true);
+});
+
+add_task(async function test_fill_hidden_by_locked_primary_password() {
+  // test that the generated password option is not present when the user
+  // didn't unlock the primary password.
+  LoginTestUtils.primaryPassword.enable();
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+      await openPasswordContextMenu(
+        browser,
+        passwordInputSelector,
+        () => false
+      );
+      let generatedPasswordItem = document.getElementById(
+        "fill-login-generated-password"
+      );
+      Assert.ok(
+        BrowserTestUtils.isVisible(generatedPasswordItem),
+        "generated password item is visible"
+      );
+      Assert.ok(
+        generatedPasswordItem.disabled,
+        "generated password item is disabled"
+      );
+
+      CONTEXT_MENU.hidePopup();
+    }
+  );
+
+  LoginTestUtils.primaryPassword.disable();
+});
+
+add_task(async function fill_generated_password_empty_field() {
+  // test that we can fill with generated password into an empty password field
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector]],
+        function checkInitialFieldValue(inputSelector) {
+          const input = content.document.querySelector(inputSelector);
+          Assert.equal(input.value.length, 0, "Password field is empty");
+          Assert.ok(
+            !input.matches(":autofill"),
+            "Password field should not be highlighted"
+          );
+        }
+      );
+
+      await doFillGeneratedPasswordContextMenuItem(
+        browser,
+        passwordInputSelector
+      );
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector]],
+        function checkFinalFieldValue(inputSelector) {
+          let { LoginTestUtils: LTU } = ChromeUtils.importESModule(
+            "resource://testing-common/LoginTestUtils.sys.mjs"
+          );
+          const input = content.document.querySelector(inputSelector);
+          Assert.equal(
+            input.value.length,
+            LTU.generation.LENGTH,
+            "Password field was filled with generated password"
+          );
+          Assert.ok(
+            input.matches(":autofill"),
+            "Password field should be highlighted"
+          );
+          LTU.loginField.checkPasswordMasked(input, false, "after fill");
+
+          info("cleaing the field");
+          input.setUserInput("");
+        }
+      );
+
+      let acPopup = document.getElementById("PopupAutoComplete");
+      await openACPopup(acPopup, browser, passwordInputSelector);
+
+      let pwgenItem = acPopup.querySelector(
+        `[originaltype="generatedPassword"]`
+      );
+      Assert.ok(
+        !pwgenItem || EventUtils.isHidden(pwgenItem),
+        "pwgen item should no longer be shown"
+      );
+
+      await closePopup(acPopup);
+    }
+  );
+});
+
+add_task(async function fill_generated_password_nonempty_field() {
+  // test that we can fill with generated password into an non-empty password field
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      await changeContentFormValues(browser, {
+        [passwordInputSelector]: "aa",
+      });
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector]],
+        function checkInitialFieldValue(inputSelector) {
+          const input = content.document.querySelector(inputSelector);
+          Assert.ok(
+            !input.matches(":autofill"),
+            "Password field should not be highlighted"
+          );
+        }
+      );
+
+      await doFillGeneratedPasswordContextMenuItem(
+        browser,
+        passwordInputSelector
+      );
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector]],
+        function checkFinalFieldValue(inputSelector) {
+          let { LoginTestUtils: LTU } = ChromeUtils.importESModule(
+            "resource://testing-common/LoginTestUtils.sys.mjs"
+          );
+          const input = content.document.querySelector(inputSelector);
+          Assert.equal(
+            input.value.length,
+            LTU.generation.LENGTH,
+            "Password field was filled with generated password"
+          );
+          Assert.ok(
+            input.matches(":autofill"),
+            "Password field should be highlighted"
+          );
+          LTU.loginField.checkPasswordMasked(input, false, "after fill");
+        }
+      );
+    }
+  );
+  LoginTestUtils.clearData();
+  LoginTestUtils.resetGeneratedPasswordsCache();
+});
+
+add_task(async function fill_generated_password_with_matching_logins() {
+  // test that we can fill a generated password when there are matching logins
+  let login = LoginTestUtils.testData.formLogin({
+    origin: "https://example.com",
+    formActionOrigin: "https://example.com",
+    username: "username",
+    password: "pass1",
+  });
+  let storageChangedPromised = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    (_, data) => data == "addLogin"
+  );
+  await Services.logins.addLoginAsync(login);
+  await storageChangedPromised;
+
+  let formFilled = listenForTestNotification("FormProcessed");
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      await formFilled;
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector]],
+        function checkInitialFieldValue(inputSelector) {
+          Assert.equal(
+            content.document.querySelector(inputSelector).value,
+            "pass1",
+            "Password field has initial value"
+          );
+        }
+      );
+
+      await doFillGeneratedPasswordContextMenuItem(
+        browser,
+        passwordInputSelector
+      );
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector]],
+        function checkFinalFieldValue(inputSelector) {
+          let { LoginTestUtils: LTU } = ChromeUtils.importESModule(
+            "resource://testing-common/LoginTestUtils.sys.mjs"
+          );
+          const input = content.document.querySelector(inputSelector);
+          Assert.equal(
+            input.value.length,
+            LTU.generation.LENGTH,
+            "Password field was filled with generated password"
+          );
+          Assert.ok(
+            input.matches(":autofill"),
+            "Password field should be highlighted"
+          );
+          LTU.loginField.checkPasswordMasked(input, false, "after fill");
+        }
+      );
+
+      await openPasswordContextMenu(browser, passwordInputSelector);
+
+      // Execute the command of the first login menuitem found at the context menu.
+      let passwordChangedPromise = ContentTask.spawn(
+        browser,
+        null,
+        async function () {
+          let passwordInput = content.document.getElementById(
+            "form-basic-password"
+          );
+          await ContentTaskUtils.waitForEvent(passwordInput, "input");
+        }
+      );
+
+      let popupMenu = document.getElementById("fill-login-popup");
+      let firstLoginItem =
+        popupMenu.getElementsByClassName("context-login-item")[0];
+      firstLoginItem.doCommand();
+
+      await passwordChangedPromise;
+
+      let contextMenu = document.getElementById("contentAreaContextMenu");
+      contextMenu.hidePopup();
+
+      // Blur the field to trigger a 'change' event.
+      await BrowserTestUtils.synthesizeKey("KEY_Tab", undefined, browser);
+      await BrowserTestUtils.synthesizeKey(
+        "KEY_Tab",
+        { shiftKey: true },
+        browser
+      );
+
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector]],
+        function checkFieldNotGeneratedPassword(inputSelector) {
+          let { LoginTestUtils: LTU } = ChromeUtils.importESModule(
+            "resource://testing-common/LoginTestUtils.sys.mjs"
+          );
+          const input = content.document.querySelector(inputSelector);
+          Assert.equal(
+            input.value,
+            "pass1",
+            "Password field was filled with the saved password"
+          );
+          LTU.loginField.checkPasswordMasked(
+            input,
+            true,
+            "after fill of a saved login"
+          );
+        }
+      );
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 2, "Check 2 logins");
+  isnot(
+    logins[0].password,
+    logins[1].password,
+    "Generated password shouldn't have changed to match the filled password"
+  );
+
+  Services.logins.removeAllUserFacingLogins();
+  LoginTestUtils.resetGeneratedPasswordsCache();
+});
+
+add_task(async function test_edited_generated_password_in_new_tab() {
+  // test that we can fill the generated password into an empty password field,
+  // edit it, and then fill the edited password.
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector]],
+        function checkInitialFieldValue(inputSelector) {
+          const input = content.document.querySelector(inputSelector);
+          Assert.equal(input.value.length, 0, "Password field is empty");
+          Assert.ok(
+            !input.matches(":autofill"),
+            "Password field should not be highlighted"
+          );
+        }
+      );
+
+      await doFillGeneratedPasswordContextMenuItem(
+        browser,
+        passwordInputSelector
+      );
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector]],
+        function checkAndEditFieldValue(inputSelector) {
+          let { LoginTestUtils: LTU } = ChromeUtils.importESModule(
+            "resource://testing-common/LoginTestUtils.sys.mjs"
+          );
+          const input = content.document.querySelector(inputSelector);
+          Assert.equal(
+            input.value.length,
+            LTU.generation.LENGTH,
+            "Password field was filled with generated password"
+          );
+          Assert.ok(
+            input.matches(":autofill"),
+            "Password field should be highlighted"
+          );
+          LTU.loginField.checkPasswordMasked(input, false, "after fill");
+        }
+      );
+
+      await BrowserTestUtils.sendChar("!", browser);
+      await BrowserTestUtils.sendChar("@", browser);
+      let storageChangedPromised = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "modifyLogin"
+      );
+      await BrowserTestUtils.synthesizeKey("KEY_Tab", undefined, browser);
+      info("Waiting for storage update");
+      await storageChangedPromised;
+    }
+  );
+
+  info("Now fill again in a new tab and ensure the edited password is used");
+
+  // Disable autofill in the new tab
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.autofillForms", false]],
+  });
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + FORM_PAGE_PATH,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+      await doFillGeneratedPasswordContextMenuItem(
+        browser,
+        passwordInputSelector
+      );
+
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector]],
+        function checkAndEditFieldValue(inputSelector) {
+          let { LoginTestUtils: LTU } = ChromeUtils.importESModule(
+            "resource://testing-common/LoginTestUtils.sys.mjs"
+          );
+          const input = content.document.querySelector(inputSelector);
+          Assert.equal(
+            input.value.length,
+            LTU.generation.LENGTH + 2,
+            "Password field was filled with edited generated password"
+          );
+          LTU.loginField.checkPasswordMasked(input, false, "after fill");
+        }
+      );
+    }
+  );
+
+  LoginTestUtils.clearData();
+  LoginTestUtils.resetGeneratedPasswordsCache();
+  await SpecialPowers.popPrefEnv();
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_context_menu_iframe.js b/toolkit/components/passwordmgr/test/browser/browser_context_menu_iframe.js
new file mode 100644
index 0000000000..f997cf3a72
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_context_menu_iframe.js
@@ -0,0 +1,223 @@
+/*
+ * Test the password manager context menu.
+ */
+
+"use strict";
+
+const TEST_ORIGIN = "https://example.com";
+
+// Test with a page that only has a form within an iframe, not in the top-level document
+const IFRAME_PAGE_PATH =
+  "/browser/toolkit/components/passwordmgr/test/browser/form_basic_iframe.html";
+
+/**
+ * Initialize logins needed for the tests and disable autofill
+ * for login forms for easier testing of manual fill.
+ */
+add_task(async function test_initialize() {
+  Services.prefs.setBoolPref("signon.autofillForms", false);
+  Services.prefs.setBoolPref("signon.schemeUpgrades", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.autofillForms");
+    Services.prefs.clearUserPref("signon.schemeUpgrades");
+  });
+  await Services.logins.addLogins(loginList());
+});
+
+/**
+ * Check if the password field is correctly filled when it's in an iframe.
+ */
+add_task(async function test_context_menu_iframe_fill() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + IFRAME_PAGE_PATH,
+    },
+    async function (browser) {
+      await openPasswordContextMenu(
+        browser,
+        "#form-basic-password",
+        () => true,
+        browser.browsingContext.children[0],
+        true
+      );
+
+      let popupMenu = document.getElementById("fill-login-popup");
+
+      // Stores the original value of username
+      function promiseFrameInputValue(name) {
+        return SpecialPowers.spawn(
+          browser.browsingContext.children[0],
+          [name],
+          function (inputname) {
+            return content.document.getElementById(inputname).value;
+          }
+        );
+      }
+      let usernameOriginalValue = await promiseFrameInputValue(
+        "form-basic-username"
+      );
+
+      // Execute the command of the first login menuitem found at the context menu.
+      let firstLoginItem =
+        popupMenu.getElementsByClassName("context-login-item")[0];
+      Assert.ok(firstLoginItem, "Found the first login item");
+
+      await TestUtils.waitForTick();
+
+      Assert.ok(
+        BrowserTestUtils.isVisible(firstLoginItem),
+        "First login menuitem is visible"
+      );
+
+      info("Clicking on the firstLoginItem");
+      // click on the login item to fill the password field, triggering an "input" event
+      popupMenu.activateItem(firstLoginItem);
+
+      let passwordValue = await TestUtils.waitForCondition(async () => {
+        let value = await promiseFrameInputValue("form-basic-password");
+        return value;
+      });
+
+      // Find the used login by it's username.
+      let login = getLoginFromUsername(firstLoginItem.label);
+      Assert.equal(
+        login.password,
+        passwordValue,
+        "Password filled and correct."
+      );
+
+      let usernameNewValue = await promiseFrameInputValue(
+        "form-basic-username"
+      );
+      Assert.equal(
+        usernameOriginalValue,
+        usernameNewValue,
+        "Username value was not changed."
+      );
+
+      let contextMenu = document.getElementById("contentAreaContextMenu");
+      contextMenu.hidePopup();
+
+      await cleanupDoorhanger();
+      await cleanupPasswordNotifications();
+    }
+  );
+});
+
+/**
+ * Check that the login context menu items don't appear on an opaque origin.
+ */
+add_task(async function test_context_menu_iframe_sandbox() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + IFRAME_PAGE_PATH,
+    },
+    async function (browser) {
+      info("Opening context menu for test_context_menu_iframe_sandbox");
+      await openPasswordContextMenu(
+        browser,
+        "#form-basic-password",
+        function checkDisabled() {
+          info("checkDisabled for test_context_menu_iframe_sandbox");
+          let popupHeader = document.getElementById("fill-login");
+          Assert.ok(
+            popupHeader.hidden,
+            "Check that the Fill Login menu item is hidden"
+          );
+          return false;
+        },
+        browser.browsingContext.children[1]
+      );
+      let contextMenu = document.getElementById("contentAreaContextMenu");
+      contextMenu.hidePopup();
+    }
+  );
+});
+
+/**
+ * Check that the login context menu item appears for sandbox="allow-same-origin"
+ */
+add_task(async function test_context_menu_iframe_sandbox_same_origin() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN + IFRAME_PAGE_PATH,
+    },
+    async function (browser) {
+      await openPasswordContextMenu(
+        browser,
+        "#form-basic-password",
+        function checkDisabled() {
+          let popupHeader = document.getElementById("fill-login");
+          Assert.ok(
+            !popupHeader.hidden,
+            "Check that the Fill Login menu item is visible"
+          );
+          Assert.ok(
+            !popupHeader.disabled,
+            "Check that the Fill Login menu item is disabled"
+          );
+          return false;
+        },
+        browser.browsingContext.children[2]
+      );
+
+      let contextMenu = document.getElementById("contentAreaContextMenu");
+      contextMenu.hidePopup();
+    }
+  );
+});
+
+/**
+ * Search for a login by it's username.
+ *
+ * Only unique login/origin combinations should be used at this test.
+ */
+function getLoginFromUsername(username) {
+  return loginList().find(login => login.username == username);
+}
+
+/**
+ * List of logins used for the test.
+ *
+ * We should only use unique usernames in this test,
+ * because we need to search logins by username. There is one duplicate u+p combo
+ * in order to test de-duping in the menu.
+ */
+function loginList() {
+  return [
+    LoginTestUtils.testData.formLogin({
+      origin: "https://example.com",
+      formActionOrigin: "https://example.com",
+      username: "username",
+      password: "password",
+    }),
+    // Same as above but HTTP in order to test de-duping.
+    LoginTestUtils.testData.formLogin({
+      origin: "http://example.com",
+      formActionOrigin: "http://example.com",
+      username: "username",
+      password: "password",
+    }),
+    LoginTestUtils.testData.formLogin({
+      origin: "http://example.com",
+      formActionOrigin: "http://example.com",
+      username: "username1",
+      password: "password1",
+    }),
+    LoginTestUtils.testData.formLogin({
+      origin: "https://example.com",
+      formActionOrigin: "https://example.com",
+      username: "username2",
+      password: "password2",
+    }),
+    LoginTestUtils.testData.formLogin({
+      origin: "http://example.org",
+      formActionOrigin: "http://example.org",
+      username: "username-cross-origin",
+      password: "password-cross-origin",
+    }),
+  ];
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_crossOriginSubmissionUsesCorrectOrigin.js b/toolkit/components/passwordmgr/test/browser/browser_crossOriginSubmissionUsesCorrectOrigin.js
new file mode 100644
index 0000000000..0aecba63a6
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_crossOriginSubmissionUsesCorrectOrigin.js
@@ -0,0 +1,53 @@
+/* Any copyright is dedicated to the Public Domain.
+ * https://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+function getDataFromNextSubmitMessage() {
+  return new Promise(resolve => {
+    LoginManagerParent.setListenerForTests((msg, data) => {
+      if (msg == "ShowDoorhanger") {
+        resolve(data);
+      }
+    });
+  });
+}
+
+add_task(async function testCrossOriginFormUsesCorrectOrigin() {
+  let dataPromise = getDataFromNextSubmitMessage();
+
+  let url =
+    "https://example.com" +
+    DIRECTORY_PATH +
+    "form_cross_origin_secure_action.html";
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function (browser) {
+      await SpecialPowers.spawn(browser.browsingContext, [], () => {
+        let doc = content.document;
+        doc.getElementById("form-basic-username").setUserInput("username");
+        doc.getElementById("form-basic-password").setUserInput("password");
+        doc.getElementById("form-basic").submit();
+        info("Submitting form");
+      });
+    }
+  );
+
+  let data = await dataPromise;
+  info("Origin retrieved from message listener");
+
+  Assert.equal(
+    data.origin,
+    "https://example.com",
+    "Message origin should match form origin"
+  );
+  isnot(
+    data.origin,
+    data.data.actionOrigin,
+    "If origin and actionOrigin match, this test will false positive"
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_deleteLoginsBackup.js b/toolkit/components/passwordmgr/test/browser/browser_deleteLoginsBackup.js
new file mode 100644
index 0000000000..a122f52845
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_deleteLoginsBackup.js
@@ -0,0 +1,282 @@
+/**
+ * Test that logins backup is deleted as expected when logins are deleted.
+ */
+
+ChromeUtils.defineESModuleGetters(this, {
+  FXA_PWDMGR_HOST: "resource://gre/modules/FxAccountsCommon.sys.mjs",
+  FXA_PWDMGR_REALM: "resource://gre/modules/FxAccountsCommon.sys.mjs",
+});
+
+const nsLoginInfo = new Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  Ci.nsILoginInfo,
+  "init"
+);
+
+const login1 = new nsLoginInfo(
+  "https://example.com",
+  "https://example.com",
+  null,
+  "notifyu1",
+  "notifyp1",
+  "user",
+  "pass"
+);
+const login2 = new nsLoginInfo(
+  "https://example.com",
+  "https://example.com",
+  null,
+  "",
+  "notifyp1",
+  "",
+  "pass"
+);
+
+const fxaKey = new nsLoginInfo(
+  FXA_PWDMGR_HOST,
+  null,
+  FXA_PWDMGR_REALM,
+  "foo@bar.com",
+  "pass2",
+  "",
+  ""
+);
+
+const loginStorePath = PathUtils.join(PathUtils.profileDir, "logins.json");
+const loginBackupPath = PathUtils.join(
+  PathUtils.profileDir,
+  "logins-backup.json"
+);
+
+async function waitForBackupUpdate() {
+  return new Promise(resolve => {
+    Services.obs.addObserver(function observer(subject, topic) {
+      Services.obs.removeObserver(observer, "logins-backup-updated");
+      resolve();
+    }, "logins-backup-updated");
+  });
+}
+
+async function loginStoreExists() {
+  return TestUtils.waitForCondition(() => IOUtils.exists(loginStorePath));
+}
+
+async function loginBackupExists() {
+  return TestUtils.waitForCondition(() => IOUtils.exists(loginBackupPath));
+}
+
+async function loginBackupDeleted() {
+  return TestUtils.waitForCondition(
+    async () => !(await IOUtils.exists(loginBackupPath))
+  );
+}
+
+// If a fxa key is stored as a login, test that logins backup is updated to only store
+// the fxa key when the last user facing login is deleted.
+add_task(
+  async function test_deleteLoginsBackup_removeAllUserFacingLogins_fxaKey() {
+    info(
+      "Testing removeAllUserFacingLogins() case when there is a saved fxa key"
+    );
+    info("Adding two logins: fxa key and one user facing login");
+    let storageUpdatePromise = TestUtils.topicObserved(
+      "password-storage-updated"
+    );
+    await Services.logins.addLoginAsync(login1);
+    Assert.ok(true, "added login1");
+    await loginStoreExists();
+    await Services.logins.addLoginAsync(fxaKey);
+    Assert.ok(true, "added fxaKey");
+    await loginBackupExists();
+    Assert.ok(true, "logins-backup.json now exists");
+    await storageUpdatePromise;
+    info("Writes to storage are complete for addLogin calls");
+
+    storageUpdatePromise = TestUtils.topicObserved("password-storage-updated");
+    info("Removing all user facing logins");
+    Services.logins.removeAllUserFacingLogins();
+    await storageUpdatePromise;
+    info("Writes to storage are complete after removeAllUserFacingLogins call");
+    await waitForBackupUpdate();
+    Assert.ok(
+      true,
+      "logins-backup.json was updated to only store the fxa key, as expected"
+    );
+
+    // Clean up.
+    // Since there is a fxa key left, we need to call removeAllLogins() or removeLogin(fxaKey)
+    // to remove the fxa key. Otherwise the test will fail in verify mode when trying to add login1
+    Services.logins.removeAllLogins();
+    await IOUtils.remove(loginStorePath);
+  }
+);
+
+// Test that logins backup is deleted when Services.logins.removeAllUserFacingLogins() is called.
+add_task(async function test_deleteLoginsBackup_removeAllUserFacingLogins() {
+  // Remove logins.json and logins-backup.json before starting.
+  info("Testing the removeAllUserFacingLogins() case");
+
+  await IOUtils.remove(loginStorePath, { ignoreAbsent: true });
+  await IOUtils.remove(loginBackupPath, { ignoreAbsent: true });
+
+  let storageUpdatePromise = TestUtils.topicObserved(
+    "password-storage-updated"
+  );
+  info("Add a login to create logins.json");
+  await Services.logins.addLoginAsync(login1);
+  await loginStoreExists();
+  Assert.ok(true, "logins.json now exists");
+
+  info("Add a second login to create logins-backup.json");
+  await Services.logins.addLoginAsync(login2);
+  await loginBackupExists();
+  info("logins-backup.json now exists");
+
+  await storageUpdatePromise;
+  info("Writes to storage are complete for addLogin calls");
+
+  storageUpdatePromise = TestUtils.topicObserved("password-storage-updated");
+  info("Removing all user facing logins");
+  Services.logins.removeAllUserFacingLogins();
+
+  await storageUpdatePromise;
+  info(
+    "Writes to storage are complete when removeAllUserFacingLogins() is called"
+  );
+  await loginBackupDeleted();
+  info(
+    "logins-backup.json was deleted as expected when all logins were removed"
+  );
+
+  // Clean up.
+  await IOUtils.remove(loginStorePath);
+});
+
+// 1. Test that logins backup is deleted when Services.logins.removeAllLogins() is called
+// 2. If a FxA key is stored as a login, test that logins backup is deleted when
+//   Services.logins.removeAllLogins() is called
+add_task(async function test_deleteLoginsBackup_removeAllLogins() {
+  // Remove logins.json and logins-backup.json before starting.
+  info("Testing the removeAllLogins() case");
+
+  await IOUtils.remove(loginStorePath, { ignoreAbsent: true });
+  await IOUtils.remove(loginBackupPath, { ignoreAbsent: true });
+
+  let storageUpdatePromise = TestUtils.topicObserved(
+    "password-storage-updated"
+  );
+  info("Add a login to create logins.json");
+  await Services.logins.addLoginAsync(login1);
+  Assert.ok(true, "added login1");
+  await loginStoreExists();
+  Assert.ok(true, "logins.json now exists");
+  await Services.logins.addLoginAsync(login2);
+  Assert.ok(true, "added login2");
+  await loginBackupExists();
+  info("logins-backup.json now exists");
+
+  await storageUpdatePromise;
+  info("Writes to storage are complete for addLogin calls");
+
+  storageUpdatePromise = TestUtils.topicObserved("password-storage-updated");
+  info("Removing all logins");
+  Services.logins.removeAllLogins();
+
+  await storageUpdatePromise;
+  info("Writes to storage are complete when removeAllLogins() is called");
+
+  await loginBackupDeleted();
+  info(
+    "logins-backup.json was deleted as expected when all logins were removed"
+  );
+  await IOUtils.remove(loginStorePath);
+
+  info("Testing the removeAllLogins() case when FxA key is present");
+  storageUpdatePromise = TestUtils.topicObserved("password-storage-updated");
+  await Services.logins.addLoginAsync(login1);
+  await loginStoreExists();
+  await Services.logins.addLoginAsync(fxaKey);
+  await loginBackupExists();
+  info("logins-backup.json now exists");
+  await storageUpdatePromise;
+  info("Write to storage are complete for addLogin calls");
+
+  storageUpdatePromise = TestUtils.topicObserved("password-storage-updated");
+  info("Removing all logins, including FxA key");
+  Services.logins.removeAllLogins();
+  await storageUpdatePromise;
+  info("Writes to storage are complete after the last removeAllLogins call");
+  await loginBackupDeleted();
+  info(
+    "logins-backup.json was deleted when the last logins were removed, as expected"
+  );
+
+  // Clean up.
+  await IOUtils.remove(loginStorePath);
+});
+
+// 1. Test that logins backup is deleted when the last saved login is removed using
+//    Services.logins.removeLogin() when no fxa key is saved.
+// 2. Test that logins backup is updated when the last saved login is removed using
+//    Services.logins.removeLogin() when a fxa key is present.
+add_task(async function test_deleteLoginsBackup_removeLogin() {
+  info("Testing the removeLogin() case when there is no saved fxa key");
+  info("Adding two logins");
+  let storageUpdatePromise = TestUtils.topicObserved(
+    "password-storage-updated"
+  );
+  await Services.logins.addLoginAsync(login1);
+  await loginStoreExists();
+  await Services.logins.addLoginAsync(login2);
+  await loginBackupExists();
+  info("logins-backup.json now exists");
+
+  await storageUpdatePromise;
+  info("Writes to storage are complete for addLogin calls");
+
+  storageUpdatePromise = TestUtils.topicObserved("password-storage-updated");
+  info("Removing one login");
+  Services.logins.removeLogin(login1);
+  await storageUpdatePromise;
+  info("Writes to storage are complete after one removeLogin call");
+  await loginBackupExists();
+
+  storageUpdatePromise = TestUtils.topicObserved("password-storage-updated");
+  info("Removing the last login");
+  Services.logins.removeLogin(login2);
+  await storageUpdatePromise;
+  info("Writes to storage are complete after the last removeLogin call");
+  await loginBackupDeleted();
+  info(
+    "logins-backup.json was deleted as expected when the last saved login was removed"
+  );
+  await IOUtils.remove(loginStorePath);
+
+  info("Testing the removeLogin() case when there is a saved fxa key");
+  info("Adding two logins: one user facing and the fxa key");
+  storageUpdatePromise = TestUtils.topicObserved("password-storage-updated");
+  await Services.logins.addLoginAsync(login1);
+  await loginStoreExists();
+  await Services.logins.addLoginAsync(fxaKey);
+  await loginBackupExists();
+  info("logins-backup.json now exists");
+
+  await storageUpdatePromise;
+  info("Writes to storage are complete for addLogin calls");
+
+  storageUpdatePromise = TestUtils.topicObserved("password-storage-updated");
+  let backupUpdate = waitForBackupUpdate();
+  Services.logins.removeLogin(login1);
+  await storageUpdatePromise;
+  info("Writes to storage are complete after one removeLogin call");
+  await backupUpdate;
+
+  await loginBackupExists();
+  info("logins-backup.json was updated to contain only the fxa key");
+
+  // Clean up.
+  // Since there is a fxa key left, we need to call removeAllLogins() or removeLogin(fxaKey)
+  // to remove the fxa key. Otherwise the test will fail in verify mode when trying to add login1
+  Services.logins.removeAllLogins();
+  await IOUtils.remove(loginStorePath);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_autocomplete_values.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_autocomplete_values.js
new file mode 100644
index 0000000000..2177a3e5e0
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_autocomplete_values.js
@@ -0,0 +1,274 @@
+/**
+ * Modify page elements and verify that they are found as options in the save/update doorhanger.
+ */
+
+const USERNAME_SELECTOR = "#form-expanded-username";
+const PASSWORD_SELECTOR = "#form-expanded-password";
+const SEARCH_SELECTOR = "#form-expanded-search";
+const CAPTCHA_SELECTOR = "#form-expanded-captcha";
+const NON_FORM_SELECTOR = "#form-expanded-non-form-input";
+
+const AUTOCOMPLETE_POPUP_SELECTOR = "#PopupAutoComplete";
+const USERNAME_DROPMARKER_SELECTOR =
+  "#password-notification-username-dropmarker";
+
+const TEST_CASES = [
+  {
+    description: "a modified username should be included in the popup",
+    modifiedFields: [
+      { [USERNAME_SELECTOR]: "new_username" },
+      { [PASSWORD_SELECTOR]: "myPassword" },
+    ],
+    expectUsernameDropmarker: true,
+    expectedValues: ["new_username"],
+  },
+  {
+    description:
+      "if no non-password fields are modified, no popup should be available",
+    modifiedFields: [{ [PASSWORD_SELECTOR]: "myPassword" }],
+    expectUsernameDropmarker: false,
+    expectedValues: [],
+  },
+  {
+    description: "all modified username fields should be included in the popup",
+    modifiedFields: [
+      { [USERNAME_SELECTOR]: "new_username" },
+      { [SEARCH_SELECTOR]: "unrelated search query" },
+      { [CAPTCHA_SELECTOR]: "someCaptcha" },
+      { [PASSWORD_SELECTOR]: "myPassword" },
+    ],
+    expectUsernameDropmarker: true,
+    expectedValues: ["new_username", "unrelated search query", "someCaptcha"],
+  },
+  {
+    description:
+      "any modified fields that don't look like usernames or passwords should not be included in the popup",
+    modifiedFields: [
+      { [PASSWORD_SELECTOR]: "myPassword" },
+      { [NON_FORM_SELECTOR]: "I dont even know what this one is" },
+    ],
+    expectUsernameDropmarker: false,
+    expectedValues: [],
+  },
+  {
+    description:
+      "when a field is modified multiple times, all CHANGE event values should be included in the popup",
+    modifiedFields: [
+      { [USERNAME_SELECTOR]: "new_username1" },
+      { [USERNAME_SELECTOR]: "new_username2" },
+      { [USERNAME_SELECTOR]: "new_username3" },
+      { [PASSWORD_SELECTOR]: "myPassword" },
+    ],
+    expectUsernameDropmarker: true,
+    expectedValues: ["new_username1", "new_username2", "new_username3"],
+  },
+  {
+    description: "empty strings should not be displayed in popup",
+    modifiedFields: [
+      { [PASSWORD_SELECTOR]: "myPassword" },
+      { [USERNAME_SELECTOR]: "new_username" },
+      { [USERNAME_SELECTOR]: "" },
+    ],
+    expectUsernameDropmarker: true,
+    expectedValues: ["new_username"],
+  },
+  {
+    description: "saved logins should be displayed in popup",
+    modifiedFields: [
+      { [USERNAME_SELECTOR]: "new_username" },
+      { [PASSWORD_SELECTOR]: "myPassword" },
+    ],
+    savedLogins: [
+      {
+        username: "savedUn1",
+        password: "somePass",
+      },
+      {
+        username: "savedUn2",
+        password: "otherPass",
+      },
+    ],
+    expectUsernameDropmarker: true,
+    expectedValues: ["new_username", "savedUn1", "savedUn2"],
+  },
+  {
+    description: "duplicated page usernames should only be displayed once",
+    modifiedFields: [
+      { [PASSWORD_SELECTOR]: "myPassword" },
+      { [USERNAME_SELECTOR]: "new_username1" },
+      { [USERNAME_SELECTOR]: "new_username2" },
+      { [USERNAME_SELECTOR]: "new_username1" },
+    ],
+    expectUsernameDropmarker: true,
+    expectedValues: ["new_username1", "new_username2"],
+  },
+  {
+    description: "non-un/pw fields also prompt doorhanger updates",
+    modifiedFields: [
+      { [PASSWORD_SELECTOR]: "myPassword" },
+      { [USERNAME_SELECTOR]: "new_username1" },
+      { [SEARCH_SELECTOR]: "search" },
+      { [CAPTCHA_SELECTOR]: "captcha" },
+    ],
+    expectUsernameDropmarker: true,
+    expectedValues: ["new_username1", "search", "captcha"],
+  },
+  // {
+  //   description: "duplicated saved/page usernames should TODO https://mozilla.invisionapp.com/share/XGXL6WZVKFJ#/screens/420547613/comments",
+  // },
+];
+
+function _validateTestCase(tc) {
+  if (tc.expectUsernameDropmarker) {
+    Assert.ok(
+      !!tc.expectedValues.length,
+      "Validate test case.  A visible dropmarker implies expected values"
+    );
+  } else {
+    Assert.ok(
+      !tc.expectedValues.length,
+      "Validate test case.  A hidden dropmarker implies no expected values"
+    );
+  }
+}
+
+async function _setPrefs() {
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.capture.inputChanges.enabled", true]],
+  });
+}
+
+async function _addSavedLogins(logins) {
+  let loginsData = logins.map(({ username }) =>
+    LoginTestUtils.testData.formLogin({
+      origin: "https://example.com",
+      formActionOrigin: "https://example.com",
+      username,
+      password: "Saved login passwords not used in this test",
+    })
+  );
+  await Services.logins.addLogins(loginsData);
+}
+
+async function _clickDropmarker(document, notificationElement) {
+  let acPopup = document.querySelector(AUTOCOMPLETE_POPUP_SELECTOR);
+  let acPopupShown = BrowserTestUtils.waitForEvent(acPopup, "popupshown");
+
+  notificationElement.querySelector(USERNAME_DROPMARKER_SELECTOR).click();
+  await acPopupShown;
+}
+
+function _getSuggestedValues(document) {
+  let suggestedValues = [];
+  let autocompletePopup = document.querySelector(AUTOCOMPLETE_POPUP_SELECTOR);
+  let numRows = autocompletePopup.view.matchCount;
+  for (let i = 0; i < numRows; i++) {
+    suggestedValues.push(autocompletePopup.view.getValueAt(i));
+  }
+  return suggestedValues;
+}
+
+add_task(async function test_edit_password() {
+  await _setPrefs();
+  for (let testCase of TEST_CASES) {
+    info("Test case: " + JSON.stringify(testCase));
+    _validateTestCase(testCase);
+
+    // Clean state before the test case is executed.
+    await LoginTestUtils.clearData();
+    await cleanupDoorhanger();
+    await cleanupPasswordNotifications();
+    Services.logins.removeAllUserFacingLogins();
+
+    // Create the pre-existing logins when needed.
+    if (testCase.savedLogins) {
+      info("Adding logins " + JSON.stringify(testCase.savedLogins));
+      await _addSavedLogins(testCase.savedLogins);
+    }
+
+    info("Opening tab");
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url:
+          "https://example.com/browser/toolkit/components/" +
+          "passwordmgr/test/browser/form_expanded.html",
+      },
+      async function (browser) {
+        info("Editing the form");
+        for (const change of testCase.modifiedFields) {
+          for (const selector in change) {
+            let newValue = change[selector];
+            info(`Setting field '${selector}' to '${newValue}'`);
+            await changeContentFormValues(browser, change);
+          }
+        }
+
+        let notif = getCaptureDoorhanger("any");
+
+        let { panel } = PopupNotifications;
+
+        let promiseShown = BrowserTestUtils.waitForEvent(panel, "popupshown");
+
+        EventUtils.synthesizeMouseAtCenter(notif.anchorElement, {});
+
+        await promiseShown;
+
+        let notificationElement = panel.childNodes[0];
+
+        let usernameDropmarker = notificationElement.querySelector(
+          USERNAME_DROPMARKER_SELECTOR
+        );
+        Assert.ok(
+          BrowserTestUtils.isVisible(usernameDropmarker) ==
+            testCase.expectUsernameDropmarker,
+          "Confirm dropmarker visibility"
+        );
+
+        if (testCase.expectUsernameDropmarker) {
+          info("Opening autocomplete popup");
+          await _clickDropmarker(document, notificationElement);
+        }
+
+        let suggestedValues = _getSuggestedValues(document);
+
+        let expectedNotFound = testCase.expectedValues.filter(
+          expected => !suggestedValues.includes(expected)
+        );
+        let foundNotExpected = suggestedValues.filter(
+          actual => !testCase.expectedValues.includes(actual)
+        );
+
+        // Log expected/actual inconsistencies
+        Assert.ok(
+          !expectedNotFound.length,
+          `All expected values should be found\nCase: "${
+            testCase.description
+          }"\nExpected: ${JSON.stringify(
+            testCase.expectedValues
+          )}\nActual: ${JSON.stringify(
+            suggestedValues
+          )}\nExpected not found: ${JSON.stringify(expectedNotFound)}
+        `
+        );
+        Assert.ok(
+          !foundNotExpected.length,
+          `All actual values should be expected\nCase: "${
+            testCase.description
+          }"\nExpected: ${JSON.stringify(
+            testCase.expectedValues
+          )}\nActual: ${JSON.stringify(
+            suggestedValues
+          )}\nFound not expected: ${JSON.stringify(foundNotExpected)}
+        `
+        );
+
+        // Clean up state
+        await cleanupDoorhanger();
+        await cleanupPasswordNotifications();
+        await clearMessageCache(browser);
+        Services.logins.removeAllUserFacingLogins();
+      }
+    );
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_autofill_then_save_password.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_autofill_then_save_password.js
new file mode 100644
index 0000000000..b30b575752
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_autofill_then_save_password.js
@@ -0,0 +1,181 @@
+/**
+ * Test that after we autofill, the site makes changes to the login, and then the
+ * user modifies their login, a save/update doorhanger is shown.
+ *
+ * This is a regression test for Bug 1632405.
+ */
+
+const testCases = [
+  {
+    name: "autofill, then delete u/p, then fill new u/p should show 'save'",
+    oldUsername: "oldUsername",
+    oldPassword: "oldPassword",
+    actions: [
+      {
+        setUsername: "newUsername",
+      },
+      {
+        setPassword: "newPassword",
+      },
+    ],
+    expectedNotification: "addLogin",
+    expectedDoorhanger: "password-save",
+  },
+  {
+    name: "autofill, then delete password, then fill new password should show 'update'",
+    oldUsername: "oldUsername",
+    oldPassword: "oldPassword",
+    actions: [
+      {
+        setPassword: "newPassword",
+      },
+    ],
+    expectedNotification: "modifyLogin",
+    expectedDoorhanger: "password-change",
+  },
+];
+
+for (let testData of testCases) {
+  let tmp = {
+    async [testData.name]() {
+      info("testing with: " + JSON.stringify(testData));
+      await test_save_change(testData);
+    },
+  };
+  add_task(tmp[testData.name]);
+}
+
+async function test_save_change({
+  name,
+  oldUsername,
+  oldPassword,
+  actions,
+  expectedNotification,
+  expectedDoorhanger,
+}) {
+  let originalPrefValue = await Services.prefs.getBoolPref(
+    "signon.testOnlyUserHasInteractedByPrefValue"
+  );
+  Services.prefs.setBoolPref(
+    "signon.testOnlyUserHasInteractedByPrefValue",
+    false
+  );
+
+  info("Starting test: " + name);
+
+  await LoginTestUtils.addLogin({
+    username: oldUsername,
+    password: oldPassword,
+    origin: "https://example.com",
+    formActionOrigin: "https://example.com",
+  });
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url:
+        "https://example.com/browser/toolkit/components/" +
+        "passwordmgr/test/browser/form_basic.html",
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+      await ContentTask.spawn(
+        browser,
+        { oldUsername, oldPassword },
+        async function awaitAutofill({ oldUsername, oldPassword }) {
+          await ContentTaskUtils.waitForCondition(
+            () =>
+              content.document.querySelector("#form-basic-username").value ==
+                oldUsername &&
+              content.document.querySelector("#form-basic-password").value ==
+                oldPassword,
+            "Await and verify autofill"
+          );
+
+          info(
+            "Triggering a page navigation that is not initiated by the user"
+          );
+          content.history.replaceState({}, "", "");
+        }
+      );
+
+      Services.prefs.setBoolPref(
+        "signon.testOnlyUserHasInteractedByPrefValue",
+        true
+      );
+
+      for (let action of actions) {
+        info(`As the user, update form with action: ${JSON.stringify(action)}`);
+        if (typeof action.setUsername !== "undefined") {
+          await changeContentFormValues(browser, {
+            "#form-basic-username": action.setUsername,
+          });
+        }
+        if (typeof action.setPassword !== "undefined") {
+          await changeContentFormValues(browser, {
+            "#form-basic-password": action.setPassword,
+          });
+        }
+      }
+
+      let expectedUsername =
+        [...actions]
+          .reverse()
+          .map(action => action.setUsername)
+          .find(username => !!username) ?? oldUsername;
+      let expectedPassword =
+        [...actions]
+          .reverse()
+          .map(action => action.setPassword)
+          .find(username => !!username) ?? oldPassword;
+
+      await ContentTask.spawn(
+        browser,
+        { expectedUsername, expectedPassword },
+        async function awaitAutofill({ expectedUsername, expectedPassword }) {
+          info("Validating updated fields");
+          Assert.equal(
+            expectedUsername,
+            content.document.querySelector("#form-basic-username").value,
+            "Verify username field updated"
+          );
+          Assert.equal(
+            expectedPassword,
+            content.document.querySelector("#form-basic-password").value,
+            "Verify password field updated"
+          );
+        }
+      );
+
+      const formSubmittedPromise = listenForTestNotification("ShowDoorhanger");
+      await SpecialPowers.spawn(browser, [], async function () {
+        let doc = this.content.document;
+        doc.getElementById("form-basic").submit();
+      });
+      await formSubmittedPromise;
+
+      info("Waiting for doorhanger of type: " + expectedDoorhanger);
+      const notif = await waitForDoorhanger(browser, expectedDoorhanger);
+
+      await checkDoorhangerUsernamePassword(expectedUsername, expectedPassword);
+
+      const promiseLogin = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == expectedNotification
+      );
+
+      await clickDoorhangerButton(notif, REMEMBER_BUTTON);
+      await promiseLogin;
+      await cleanupDoorhanger(notif); // clean slate for the next test
+
+      Services.prefs.setBoolPref(
+        "signon.testOnlyUserHasInteractedByPrefValue",
+        originalPrefValue
+      );
+    }
+  );
+
+  // Clean up the database before the next test case is executed.
+  Services.logins.removeAllUserFacingLogins();
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_crossframe.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_crossframe.js
new file mode 100644
index 0000000000..8c4770d510
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_crossframe.js
@@ -0,0 +1,236 @@
+const OUTER_URL =
+  "https://test1.example.com:443" + DIRECTORY_PATH + "form_crossframe.html";
+
+requestLongerTimeout(2);
+
+async function acceptPasswordSave() {
+  let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+  let promiseNewSavedPassword = TestUtils.topicObserved(
+    "LoginStats:NewSavedPassword",
+    (subject, data) => subject == gBrowser.selectedBrowser
+  );
+  clickDoorhangerButton(notif, REMEMBER_BUTTON);
+  await promiseNewSavedPassword;
+}
+
+function checkFormFields(browsingContext, prefix, username, password) {
+  return SpecialPowers.spawn(
+    browsingContext,
+    [prefix, username, password],
+    (formPrefix, expectedUsername, expectedPassword) => {
+      let doc = content.document;
+      Assert.equal(
+        doc.getElementById(formPrefix + "-username").value,
+        expectedUsername,
+        "username matches"
+      );
+      Assert.equal(
+        doc.getElementById(formPrefix + "-password").value,
+        expectedPassword,
+        "password matches"
+      );
+    }
+  );
+}
+
+function listenForNotifications(count, expectedFormOrigin) {
+  return new Promise(resolve => {
+    let notifications = [];
+    LoginManagerParent.setListenerForTests((msg, data) => {
+      if (msg == "FormProcessed") {
+        notifications.push("FormProcessed: " + data.browsingContext.id);
+      } else if (msg == "ShowDoorhanger") {
+        Assert.equal(
+          data.origin,
+          expectedFormOrigin,
+          "Message origin should match expected"
+        );
+        notifications.push("FormSubmit: " + data.data.usernameField.name);
+      }
+      if (notifications.length == count) {
+        resolve(notifications);
+      }
+    });
+  });
+}
+
+async function verifyNotifications(notifyPromise, expected) {
+  let actual = await notifyPromise;
+
+  Assert.equal(actual.length, expected.length, "Extra notification(s) sent");
+  let expectedItem;
+  while ((expectedItem = expected.pop())) {
+    let index = actual.indexOf(expectedItem);
+    if (index >= 0) {
+      actual.splice(index, 1);
+    } else {
+      Assert.ok(false, "Expected notification '" + expectedItem + "' not sent");
+    }
+  }
+}
+
+// Make sure there is an autocomplete result for the frame's saved login and select it.
+async function autocompleteLoginInIFrame(
+  browser,
+  iframeBrowsingContext,
+  selector
+) {
+  let popup = document.getElementById("PopupAutoComplete");
+  Assert.ok(popup, "Got popup");
+
+  await openACPopup(popup, browser, selector, iframeBrowsingContext);
+
+  let autocompleteLoginResult = popup.querySelector(
+    `[originaltype="loginWithOrigin"]`
+  );
+  Assert.ok(autocompleteLoginResult, "Got login richlistitem");
+
+  let promiseHidden = BrowserTestUtils.waitForEvent(popup, "popuphidden");
+
+  await EventUtils.synthesizeKey("KEY_ArrowDown");
+  await EventUtils.synthesizeKey("KEY_Enter");
+
+  await promiseHidden;
+}
+
+/*
+ * In this test, a frame is loaded with a document that contains a username
+ * and password field. This frame also contains another child iframe that
+ * itself contains a username and password field. This inner frame is loaded
+ * from a different domain than the first.
+ *
+ * locationMode should be false to submit forms, or true to click a button
+ * which changes the location instead. The latter should still save the
+ * username and password.
+ */
+async function submitSomeCrossSiteFrames(locationMode) {
+  info("Check with location mode " + locationMode);
+  let notifyPromise = listenForNotifications(2);
+
+  let firsttab = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    OUTER_URL
+  );
+
+  let outerFrameBC = firsttab.linkedBrowser.browsingContext;
+  let innerFrameBC = outerFrameBC.children[0];
+
+  await verifyNotifications(notifyPromise, [
+    "FormProcessed: " + outerFrameBC.id,
+    "FormProcessed: " + innerFrameBC.id,
+  ]);
+
+  // Fill in the username and password for both the outer and inner frame
+  // and submit the inner frame.
+  notifyPromise = listenForNotifications(1, "https://test2.example.org");
+  info("submit page after changing inner form");
+
+  await SpecialPowers.spawn(outerFrameBC, [], () => {
+    let doc = content.document;
+    doc.getElementById("outer-username").setUserInput("outer");
+    doc.getElementById("outer-password").setUserInput("outerpass");
+  });
+
+  await SpecialPowers.spawn(innerFrameBC, [locationMode], doClick => {
+    let doc = content.document;
+    doc.getElementById("inner-username").setUserInput("inner");
+    doc.getElementById("inner-password").setUserInput("innerpass");
+    if (doClick) {
+      doc.getElementById("inner-gobutton").click();
+    } else {
+      doc.getElementById("inner-form").submit();
+    }
+  });
+
+  await acceptPasswordSave();
+
+  await verifyNotifications(notifyPromise, ["FormSubmit: username"]);
+
+  // Next, open a second tab with the same page in it to verify that the data gets filled properly.
+  notifyPromise = listenForNotifications(2);
+  let secondtab = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    OUTER_URL
+  );
+
+  let outerFrameBC2 = secondtab.linkedBrowser.browsingContext;
+  let innerFrameBC2 = outerFrameBC2.children[0];
+  await verifyNotifications(notifyPromise, [
+    "FormProcessed: " + outerFrameBC2.id,
+    "FormProcessed: " + innerFrameBC2.id,
+  ]);
+
+  // We don't expect the innerFrame to be autofilled with the saved login, since
+  // it is cross-origin with the top level frame, so we autocomplete instead.
+  info("Autocompleting saved login into inner form");
+  await autocompleteLoginInIFrame(
+    secondtab.linkedBrowser,
+    innerFrameBC2,
+    "#inner-username"
+  );
+
+  await checkFormFields(outerFrameBC2, "outer", "", "");
+  await checkFormFields(innerFrameBC2, "inner", "inner", "innerpass");
+
+  // Next, change the username and password fields in the outer frame and submit.
+  notifyPromise = listenForNotifications(1, "https://test1.example.com");
+  info("submit page after changing outer form");
+
+  await SpecialPowers.spawn(outerFrameBC2, [locationMode], doClick => {
+    let doc = content.document;
+    doc.getElementById("outer-username").setUserInput("outer2");
+    doc.getElementById("outer-password").setUserInput("outerpass2");
+    if (doClick) {
+      doc.getElementById("outer-gobutton").click();
+    } else {
+      doc.getElementById("outer-form").submit();
+    }
+
+    doc.getElementById("outer-form").submit();
+  });
+
+  await acceptPasswordSave();
+  await verifyNotifications(notifyPromise, ["FormSubmit: outer-username"]);
+
+  // Finally, open a third tab with the same page in it to verify that the data gets filled properly.
+  notifyPromise = listenForNotifications(2);
+  let thirdtab = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    OUTER_URL
+  );
+
+  let outerFrameBC3 = thirdtab.linkedBrowser.browsingContext;
+  let innerFrameBC3 = outerFrameBC3.children[0];
+  await verifyNotifications(notifyPromise, [
+    "FormProcessed: " + outerFrameBC3.id,
+    "FormProcessed: " + innerFrameBC3.id,
+  ]);
+
+  // We don't expect the innerFrame to be autofilled with the saved login, since
+  // it is cross-origin with the top level frame, so we autocomplete instead.
+  info("Autocompleting saved login into inner form");
+  await autocompleteLoginInIFrame(
+    thirdtab.linkedBrowser,
+    innerFrameBC3,
+    "#inner-username"
+  );
+
+  await checkFormFields(outerFrameBC3, "outer", "outer2", "outerpass2");
+  await checkFormFields(innerFrameBC3, "inner", "inner", "innerpass");
+
+  LoginManagerParent.setListenerForTests(null);
+
+  await BrowserTestUtils.removeTab(firsttab);
+  await BrowserTestUtils.removeTab(secondtab);
+  await BrowserTestUtils.removeTab(thirdtab);
+
+  LoginTestUtils.clearData();
+}
+
+add_task(async function cross_site_frames_submit() {
+  await submitSomeCrossSiteFrames(false);
+});
+
+add_task(async function cross_site_frames_changelocation() {
+  await submitSomeCrossSiteFrames(true);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_dismissed_for_ccnumber.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_dismissed_for_ccnumber.js
new file mode 100644
index 0000000000..eeaa211da8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_dismissed_for_ccnumber.js
@@ -0,0 +1,202 @@
+"use strict";
+
+const TEST_ORIGIN = "https://example.com";
+const BASIC_FORM_PAGE_PATH = DIRECTORY_PATH + "form_basic.html";
+
+add_task(async function test_doorhanger_dismissal_un() {
+  let url = TEST_ORIGIN + BASIC_FORM_PAGE_PATH;
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function test_un_value_as_ccnumber(browser) {
+      // If the username field has a credit card number and if
+      // the password field is a three digit numberic value,
+      // we automatically dismiss the save logins prompt on submission.
+
+      let passwordFilledPromise = listenForTestNotification(
+        "PasswordEditedOrGenerated"
+      );
+      await changeContentFormValues(browser, {
+        "#form-basic-password": "123",
+        // We are interested in the state of the doorhanger created and don't want a
+        // false positive from the password-edited handling
+        "#form-basic-username": "4111111111111111",
+      });
+      info("Waiting for passwordFilledPromise");
+      await passwordFilledPromise;
+      // reset doorhanger/notifications, we're only interested in the submit outcome
+      await cleanupDoorhanger();
+      await cleanupPasswordNotifications();
+      // reset message cache so we can disambiguate between dismissed doorhanger from
+      // password edited vs form submitted w. cc number as username
+      await clearMessageCache(browser);
+
+      let processedPromise = listenForTestNotification("ShowDoorhanger");
+      await SpecialPowers.spawn(browser, [], async () => {
+        content.document.getElementById("form-basic-submit").click();
+      });
+      info("Waiting for FormSubmit");
+      await processedPromise;
+
+      let notif = getCaptureDoorhanger("password-save");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(
+        notif.dismissed,
+        "notification popup was automatically dismissed"
+      );
+      await cleanupDoorhanger(notif);
+    }
+  );
+});
+
+add_task(async function test_doorhanger_dismissal_pw() {
+  let url = TEST_ORIGIN + BASIC_FORM_PAGE_PATH;
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function test_pw_value_as_ccnumber(browser) {
+      // If the password field has a credit card number and if
+      // the password field is also tagged autocomplete="cc-number",
+      // we automatically dismiss the save logins prompt on submission.
+
+      let passwordFilledPromise = listenForTestNotification(
+        "PasswordEditedOrGenerated"
+      );
+      await changeContentFormValues(browser, {
+        "#form-basic-password": "4111111111111111",
+        "#form-basic-username": "aaa",
+      });
+      await SpecialPowers.spawn(browser, [], async () => {
+        content.document
+          .getElementById("form-basic-password")
+          .setAttribute("autocomplete", "cc-number");
+      });
+      await passwordFilledPromise;
+      // reset doorhanger/notifications, we're only interested in the submit outcome
+      await cleanupDoorhanger();
+      await cleanupPasswordNotifications();
+      // reset message cache so we can disambiguate between dismissed doorhanger from
+      // password edited vs form submitted w. cc number as password
+      await clearMessageCache(browser);
+
+      let processedPromise = listenForTestNotification("ShowDoorhanger");
+      await SpecialPowers.spawn(browser, [], async () => {
+        content.document.getElementById("form-basic-submit").click();
+      });
+      await processedPromise;
+
+      let notif = getCaptureDoorhanger("password-save");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(
+        notif.dismissed,
+        "notification popup was automatically dismissed"
+      );
+      await cleanupDoorhanger(notif);
+    }
+  );
+});
+
+add_task(async function test_doorhanger_shown_on_un_with_invalid_ccnumber() {
+  let url = TEST_ORIGIN + BASIC_FORM_PAGE_PATH;
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function test_un_with_invalid_cc_number(browser) {
+      // If the username field has a CC number that is invalid,
+      // we show the doorhanger to save logins like we usually do.
+
+      let passwordFilledPromise = listenForTestNotification(
+        "PasswordEditedOrGenerated"
+      );
+      await changeContentFormValues(browser, {
+        "#form-basic-password": "411",
+        "#form-basic-username": "1234123412341234",
+      });
+
+      await passwordFilledPromise;
+      // reset doorhanger/notifications, we're only interested in the submit outcome
+      await cleanupDoorhanger();
+      await cleanupPasswordNotifications();
+      // reset message cache so we can disambiguate between dismissed doorhanger from
+      // password edited vs form submitted w. cc number as password
+      await clearMessageCache(browser);
+
+      let processedPromise = listenForTestNotification("ShowDoorhanger");
+      await SpecialPowers.spawn(browser, [], async () => {
+        content.document.getElementById("form-basic-submit").click();
+      });
+      await processedPromise;
+
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(
+        !notif.dismissed,
+        "notification popup was not automatically dismissed"
+      );
+      await cleanupDoorhanger(notif);
+    }
+  );
+});
+
+add_task(async function test_doorhanger_dismissal_on_change() {
+  let url = TEST_ORIGIN + BASIC_FORM_PAGE_PATH;
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function test_change_in_pw(browser) {
+      let nsLoginInfo = new Components.Constructor(
+        "@mozilla.org/login-manager/loginInfo;1",
+        Ci.nsILoginInfo,
+        "init"
+      );
+      let login = new nsLoginInfo(
+        TEST_ORIGIN,
+        TEST_ORIGIN,
+        null,
+        "4111111111111111",
+        "111", // password looks like a card security code
+        "form-basic-username",
+        "form-basic-password"
+      );
+      await Services.logins.addLoginAsync(login);
+
+      let passwordFilledPromise = listenForTestNotification(
+        "PasswordEditedOrGenerated"
+      );
+
+      await changeContentFormValues(browser, {
+        "#form-basic-password": "222", // password looks like a card security code
+        "#form-basic-username": "4111111111111111",
+      });
+      await passwordFilledPromise;
+      // reset doorhanger/notifications, we're only interested in the submit outcome
+      await cleanupDoorhanger();
+      await cleanupPasswordNotifications();
+      // reset message cache so we can disambiguate between dismissed doorhanger from
+      // password edited vs form submitted w. cc number as username
+      await clearMessageCache(browser);
+
+      let processedPromise = listenForTestNotification("ShowDoorhanger");
+      await SpecialPowers.spawn(browser, [], async () => {
+        content.document.getElementById("form-basic-submit").click();
+      });
+      await processedPromise;
+
+      let notif = getCaptureDoorhanger("password-change");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(
+        notif.dismissed,
+        "notification popup was automatically dismissed"
+      );
+      await cleanupDoorhanger(notif);
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_empty_password.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_empty_password.js
new file mode 100644
index 0000000000..15c3d52263
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_empty_password.js
@@ -0,0 +1,42 @@
+add_setup(async function () {
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.rememberSignons.visibilityToggle", true]],
+  });
+});
+
+/**
+ * Test that the doorhanger main action button is disabled
+ * when the password field is empty.
+ *
+ * Also checks that submiting an empty password throws an error.
+ */
+add_task(async function test_empty_password() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "https://example.com/browser/toolkit/components/passwordmgr/test/browser/form_basic.html",
+    },
+    async function (browser) {
+      // Submit the form in the content page with the credentials from the test
+      // case. This will cause the doorhanger notification to be displayed.
+      await SpecialPowers.spawn(browser, [], async function () {
+        let doc = content.document;
+        doc.getElementById("form-basic-username").setUserInput("username");
+        doc.getElementById("form-basic-password").setUserInput("pw");
+        doc.getElementById("form-basic").submit();
+      });
+
+      await waitForDoorhanger(browser, "password-save");
+      // Synthesize input to empty the field
+      await updateDoorhangerInputValues({
+        password: "",
+      });
+
+      let notificationElement = PopupNotifications.panel.childNodes[0];
+      let mainActionButton = notificationElement.button;
+
+      Assert.ok(mainActionButton.disabled, "Main action button is disabled");
+      await hideDoorhangerPopup();
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_form_password_edit.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_form_password_edit.js
new file mode 100644
index 0000000000..23afd2c6ab
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_form_password_edit.js
@@ -0,0 +1,562 @@
+/**
+ * Test changed (not submitted) passwords produce the right doorhangers/notifications
+ */
+
+/* eslint no-shadow:"off" */
+
+"use strict";
+
+// The origin for the test URIs.
+const TEST_ORIGIN = "https://example.com";
+const BASIC_FORM_PAGE_PATH = DIRECTORY_PATH + "form_basic.html";
+const passwordInputSelector = "#form-basic-password";
+const usernameInputSelector = "#form-basic-username";
+
+let testCases = [
+  {
+    name: "Enter password",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [],
+    formDefaults: {},
+    formChanges: {
+      [passwordInputSelector]: "abcXYZ",
+    },
+    expected: {
+      initialForm: {
+        username: "",
+        password: "",
+      },
+      doorhanger: {
+        type: "password-save",
+        dismissed: true,
+        anchorExtraAttr: "",
+        username: "",
+        password: "abcXYZ",
+        toggle: "visible",
+      },
+    },
+  },
+  {
+    name: "Change password",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [],
+    formDefaults: {
+      [passwordInputSelector]: "pass1",
+    },
+    formChanges: {
+      [passwordInputSelector]: "pass-changed",
+    },
+    expected: {
+      initialForm: {
+        username: "",
+        password: "pass1",
+      },
+      doorhanger: {
+        type: "password-save",
+        dismissed: true,
+        anchorExtraAttr: "",
+        username: "",
+        password: "pass-changed",
+        toggle: "visible",
+      },
+    },
+  },
+  {
+    name: "Change autofilled password",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [{ username: "user1", password: "autopass" }],
+    formDefaults: {},
+    formChanges: {
+      [passwordInputSelector]: "autopass-changed",
+    },
+    expected: {
+      initialForm: {
+        username: "user1",
+        password: "autopass",
+      },
+      doorhanger: {
+        type: "password-change",
+        dismissed: true,
+        anchorExtraAttr: "",
+        username: "user1",
+        password: "autopass-changed",
+      },
+    },
+  },
+  {
+    name: "Change autofilled username and password",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [{ username: "user1", password: "pass1" }],
+    formDefaults: {},
+    formChanges: {
+      [usernameInputSelector]: "user2",
+      [passwordInputSelector]: "pass2",
+    },
+    expected: {
+      initialForm: {
+        username: "user1",
+        password: "pass1",
+      },
+      doorhanger: {
+        type: "password-save",
+        dismissed: true,
+        anchorExtraAttr: "",
+        username: "user2",
+        password: "pass2",
+        toggle: "visible",
+      },
+    },
+  },
+  {
+    name: "Change password pref disabled",
+    prefEnabled: false,
+    isLoggedIn: true,
+    logins: [],
+    formDefaults: {
+      [passwordInputSelector]: "pass1",
+    },
+    formChanges: {
+      [passwordInputSelector]: "pass-changed",
+    },
+    expected: {
+      initialForm: {
+        username: "",
+        password: "pass1",
+      },
+      doorhanger: null,
+    },
+  },
+  {
+    name: "Change to new username",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [{ username: "user1", password: "pass1" }],
+    formDefaults: {},
+    formChanges: {
+      [usernameInputSelector]: "user2",
+    },
+    expected: {
+      initialForm: {
+        username: "user1",
+        password: "pass1",
+      },
+      doorhanger: {
+        type: "password-save",
+        dismissed: true,
+        anchorExtraAttr: "",
+        username: "user2",
+        password: "pass1",
+        toggle: "visible",
+      },
+    },
+  },
+  {
+    name: "Change to existing username, different password",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [{ username: "user-saved", password: "pass1" }],
+    formDefaults: {
+      [usernameInputSelector]: "user-prefilled",
+      [passwordInputSelector]: "pass2",
+    },
+    formChanges: {
+      [usernameInputSelector]: "user-saved",
+    },
+    expected: {
+      initialForm: {
+        username: "user-prefilled",
+        password: "pass2",
+      },
+      doorhanger: {
+        type: "password-change",
+        dismissed: true,
+        anchorExtraAttr: "",
+        username: "user-saved",
+        password: "pass2",
+        toggle: "visible",
+      },
+    },
+  },
+  {
+    name: "Add username to existing password",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [{ username: "", password: "pass1" }],
+    formDefaults: {},
+    formChanges: {
+      [usernameInputSelector]: "user1",
+    },
+    expected: {
+      initialForm: {
+        username: "",
+        password: "pass1",
+      },
+      doorhanger: {
+        type: "password-change",
+        dismissed: true,
+        anchorExtraAttr: "",
+        username: "user1",
+        password: "pass1",
+        toggle: "visible",
+      },
+    },
+  },
+  {
+    name: "Change to existing username, password",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [{ username: "user1", password: "pass1" }],
+    formDefaults: {
+      [usernameInputSelector]: "user",
+      [passwordInputSelector]: "pass",
+    },
+    formChanges: {
+      [passwordInputSelector]: "pass1",
+      [usernameInputSelector]: "user1",
+    },
+    expected: {
+      initialForm: {
+        username: "user",
+        password: "pass",
+      },
+      doorhanger: null,
+    },
+  },
+  {
+    name: "Ensure a dismissed password-save doorhanger appears on an input event when editing an unsaved password",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [],
+    formDefaults: {},
+    formChanges: {
+      [passwordInputSelector]: "a",
+    },
+    shouldBlur: false,
+    expected: {
+      initialForm: {
+        username: "",
+        password: "",
+      },
+      doorhanger: {
+        type: "password-save",
+        dismissed: true,
+        anchorExtraAttr: "",
+        username: "",
+        password: "a",
+        toggle: "visible",
+      },
+    },
+  },
+  {
+    name: "Ensure a dismissed password-save doorhanger appears with the latest input value upon editing an unsaved password",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [],
+    formDefaults: {},
+    formChanges: {
+      [passwordInputSelector]: "a",
+      [passwordInputSelector]: "ab",
+      [passwordInputSelector]: "abc",
+    },
+    shouldBlur: false,
+    expected: {
+      initialForm: {
+        username: "",
+        password: "",
+      },
+      doorhanger: {
+        type: "password-save",
+        dismissed: true,
+        anchorExtraAttr: "",
+        username: "",
+        password: "abc",
+        toggle: "visible",
+      },
+    },
+  },
+  {
+    name: "Ensure a dismissed password-change doorhanger appears on an input event when editing a saved password",
+    prefEnabled: true,
+    isLoggedIn: true,
+    logins: [{ username: "", password: "pass1" }],
+    formDefaults: {},
+    formChanges: {
+      [passwordInputSelector]: "pass",
+    },
+    shouldBlur: false,
+    expected: {
+      initialForm: {
+        username: "",
+        password: "pass1",
+      },
+      doorhanger: {
+        type: "password-change",
+        dismissed: true,
+        anchorExtraAttr: "",
+        username: "",
+        password: "pass",
+        toggle: "visible",
+      },
+    },
+  },
+  {
+    name: "Ensure no dismissed doorhanger is shown on 'input' when Primary Password is locked",
+    prefEnabled: true,
+    isLoggedIn: false,
+    logins: [],
+    formDefaults: {},
+    formChanges: {
+      [passwordInputSelector]: "pass",
+    },
+    shouldBlur: false,
+    expected: {
+      initialForm: {
+        username: "",
+        password: "",
+      },
+      doorhanger: null,
+    },
+  },
+  {
+    name: "Ensure no dismissed doorhanger is shown on 'change' when Primary Password is locked",
+    prefEnabled: true,
+    isLoggedIn: false,
+    logins: [],
+    formDefaults: {},
+    formChanges: {
+      [passwordInputSelector]: "pass",
+    },
+    shouldBlur: true,
+    expected: {
+      initialForm: {
+        username: "",
+        password: "",
+      },
+      doorhanger: null,
+    },
+  },
+];
+
+requestLongerTimeout(2);
+SimpleTest.requestCompleteLog();
+
+for (let testData of testCases) {
+  let tmp = {
+    async [testData.name]() {
+      await SpecialPowers.pushPrefEnv({
+        set: [["signon.passwordEditCapture.enabled", testData.prefEnabled]],
+      });
+      if (!testData.isLoggedIn) {
+        // Enable Primary Password
+        LoginTestUtils.primaryPassword.enable();
+      }
+      for (let passwordFieldType of ["password", "text"]) {
+        info(
+          "testing with type=" +
+            passwordFieldType +
+            ": " +
+            JSON.stringify(testData)
+        );
+        await testPasswordChange(testData, { passwordFieldType });
+      }
+      if (!testData.isLoggedIn) {
+        LoginTestUtils.primaryPassword.disable();
+      }
+      await SpecialPowers.popPrefEnv();
+    },
+  };
+  add_task(tmp[testData.name]);
+}
+
+async function testPasswordChange(
+  {
+    logins = [],
+    formDefaults = {},
+    formChanges = {},
+    expected,
+    isLoggedIn,
+    shouldBlur = true,
+  },
+  { passwordFieldType }
+) {
+  await LoginTestUtils.clearData();
+  await cleanupDoorhanger();
+
+  let url = TEST_ORIGIN + BASIC_FORM_PAGE_PATH;
+  for (let login of logins) {
+    await LoginTestUtils.addLogin(login);
+  }
+
+  for (let login of await Services.logins.getAllLogins()) {
+    info(`Saved login: ${login.username}, ${login.password}, ${login.origin}`);
+  }
+
+  let formProcessedPromise = listenForTestNotification("FormProcessed");
+  info("Opening tab with url: " + url);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function (browser) {
+      info(`Opened tab with url: ${url}, waiting for focus`);
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      info("Waiting for form-processed message");
+      await formProcessedPromise;
+      await initForm(browser, formDefaults, { passwordFieldType });
+      await checkForm(browser, expected.initialForm);
+      info("form checked");
+
+      // A message is still sent to the parent process when Primary Password is enabled
+      let notificationMessage =
+        expected.doorhanger || !isLoggedIn
+          ? "PasswordEditedOrGenerated"
+          : "PasswordIgnoreEdit";
+      let passwordTestNotification =
+        listenForTestNotification(notificationMessage);
+
+      await changeContentFormValues(browser, formChanges, shouldBlur);
+
+      info(
+        `form edited, waiting for test notification of ${notificationMessage}`
+      );
+
+      await passwordTestNotification;
+      info("Resolved passwordTestNotification promise");
+
+      if (!expected.doorhanger) {
+        let notif;
+        try {
+          await TestUtils.waitForCondition(
+            () => {
+              return (notif = PopupNotifications.getNotification(
+                "password",
+                browser
+              ));
+            },
+            `Waiting to ensure no notification`,
+            undefined,
+            25
+          );
+        } catch (ex) {}
+        Assert.ok(!notif, "No doorhanger expected");
+        // the remainder of the test is for doorhanger-expected cases
+        return;
+      }
+
+      let notificationType = expected.doorhanger.type;
+      Assert.ok(
+        /^password-save|password-change$/.test(notificationType),
+        "test provided an expected notification type: " + notificationType
+      );
+      info("waiting for doorhanger");
+      await waitForDoorhanger(browser, notificationType);
+
+      info("verifying doorhanger");
+      let notif = await openAndVerifyDoorhanger(
+        browser,
+        notificationType,
+        expected.doorhanger
+      );
+      Assert.ok(notif, "Doorhanger was shown");
+
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, DONT_CHANGE_BUTTON);
+      await promiseHidden;
+
+      info("cleanup doorhanger");
+      await cleanupDoorhanger(notif);
+    }
+  );
+}
+
+async function initForm(browser, formDefaults, passwordFieldType) {
+  await ContentTask.spawn(
+    browser,
+    { passwordInputSelector, passwordFieldType },
+    async function ({ passwordInputSelector, passwordFieldType }) {
+      content.document.querySelector(passwordInputSelector).type =
+        passwordFieldType;
+    }
+  );
+  await ContentTask.spawn(
+    browser,
+    formDefaults,
+    async function (selectorValues) {
+      for (let [sel, value] of Object.entries(selectorValues)) {
+        content.document.querySelector(sel).value = value;
+      }
+    }
+  );
+}
+
+async function checkForm(browser, expected) {
+  await ContentTask.spawn(
+    browser,
+    {
+      [passwordInputSelector]: expected.password,
+      [usernameInputSelector]: expected.username,
+    },
+    async function contentCheckForm(selectorValues) {
+      for (let [sel, value] of Object.entries(selectorValues)) {
+        let field = content.document.querySelector(sel);
+        Assert.equal(
+          field.value,
+          value,
+          sel + " has the expected initial value"
+        );
+      }
+    }
+  );
+}
+
+async function openAndVerifyDoorhanger(browser, type, expected) {
+  // check a dismissed prompt was shown with extraAttr attribute
+  let notif = getCaptureDoorhanger(type);
+  Assert.ok(notif, `${type} doorhanger was created`);
+  Assert.equal(
+    notif.dismissed,
+    expected.dismissed,
+    "Check notification dismissed property"
+  );
+  Assert.equal(
+    notif.anchorElement.getAttribute("extraAttr"),
+    expected.anchorExtraAttr,
+    "Check icon extraAttr attribute"
+  );
+  let { panel } = PopupNotifications;
+  // if the doorhanged is dimissed, we will open it to check panel contents
+  Assert.equal(panel.state, "closed", "Panel is initially closed");
+  let promiseShown = BrowserTestUtils.waitForEvent(panel, "popupshown");
+  // synthesize click on anchor as this also blurs the form field triggering
+  // a change event
+  EventUtils.synthesizeMouseAtCenter(notif.anchorElement, {});
+  await promiseShown;
+  await Promise.resolve();
+  await checkDoorhangerUsernamePassword(expected.username, expected.password);
+
+  let notificationElement = PopupNotifications.panel.childNodes[0];
+  let checkbox = notificationElement.querySelector(
+    "#password-notification-visibilityToggle"
+  );
+
+  if (expected.toggle == "visible") {
+    // Bug 1692284
+    // Assert.ok(BrowserTestUtils.isVisible(checkbox), "Toggle checkbox visible as expected");
+  } else if (expected.toggle == "hidden") {
+    Assert.ok(
+      BrowserTestUtils.isHidden(checkbox),
+      "Toggle checkbox hidden as expected"
+    );
+  } else {
+    info("Not checking toggle checkbox visibility");
+  }
+  return notif;
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_generated_password.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_generated_password.js
new file mode 100644
index 0000000000..3740dad1b9
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_generated_password.js
@@ -0,0 +1,1845 @@
+/**
+ * Test using the generated passwords produces the right doorhangers/notifications
+ */
+
+/* eslint no-shadow:"off" */
+
+"use strict";
+
+// The origin for the test URIs.
+const TEST_ORIGIN = "https://example.com";
+const FORM_PAGE_PATH =
+  "/browser/toolkit/components/passwordmgr/test/browser/form_basic.html";
+const passwordInputSelector = "#form-basic-password";
+const usernameInputSelector = "#form-basic-username";
+
+requestLongerTimeout(2);
+
+async function task_setup() {
+  Services.logins.removeAllUserFacingLogins();
+  LoginTestUtils.resetGeneratedPasswordsCache();
+  await cleanupPasswordNotifications();
+  await LoginTestUtils.remoteSettings.setupImprovedPasswordRules();
+}
+
+async function setup_withOneLogin(username = "username", password = "pass1") {
+  // Reset to a single, known login
+  await task_setup();
+  let login = await LoginTestUtils.addLogin({ username, password });
+  return login;
+}
+
+async function setup_withNoLogins() {
+  // Reset to a single, known login
+  await task_setup();
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "0 logins at the start of the test"
+  );
+}
+
+async function fillGeneratedPasswordFromACPopup(
+  browser,
+  passwordInputSelector
+) {
+  let popup = document.getElementById("PopupAutoComplete");
+  Assert.ok(popup, "Got popup");
+  await openACPopup(popup, browser, passwordInputSelector);
+  await fillGeneratedPasswordFromOpenACPopup(browser, passwordInputSelector);
+}
+
+async function checkPromptContents(
+  anchorElement,
+  browser,
+  expectedPasswordLength = 0
+) {
+  let { panel } = PopupNotifications;
+  Assert.ok(PopupNotifications.isPanelOpen, "Confirm popup is open");
+  let notificationElement = panel.childNodes[0];
+  if (expectedPasswordLength) {
+    info(
+      `Waiting for password value to be ${expectedPasswordLength} chars long`
+    );
+    await BrowserTestUtils.waitForCondition(() => {
+      return (
+        notificationElement.querySelector("#password-notification-password")
+          .value.length == expectedPasswordLength
+      );
+    }, "Wait for nsLoginManagerPrompter writeDataToUI()");
+  }
+
+  return {
+    passwordValue: notificationElement.querySelector(
+      "#password-notification-password"
+    ).value,
+    usernameValue: notificationElement.querySelector(
+      "#password-notification-username"
+    ).value,
+  };
+}
+
+async function verifyGeneratedPasswordWasFilled(
+  browser,
+  passwordInputSelector
+) {
+  await SpecialPowers.spawn(
+    browser,
+    [[passwordInputSelector]],
+    function checkFinalFieldValue(inputSelector) {
+      let { LoginTestUtils: LTU } = ChromeUtils.importESModule(
+        "resource://testing-common/LoginTestUtils.sys.mjs"
+      );
+      let passwordInput = content.document.querySelector(inputSelector);
+      Assert.equal(
+        passwordInput.value.length,
+        LTU.generation.LENGTH,
+        "Password field was filled with generated password"
+      );
+    }
+  );
+}
+
+async function openFormInNewTab(url, formValues, taskFn) {
+  let formFilled = listenForTestNotification("FormProcessed");
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      await formFilled;
+
+      await SpecialPowers.spawn(
+        browser,
+        [formValues],
+        async function prepareAndCheckForm({
+          password: passwordProps,
+          username: usernameProps,
+        }) {
+          let doc = content.document;
+          // give the form an action so we can know when submit is complete
+          doc.querySelector("form").action = "/";
+
+          let props = passwordProps;
+          if (props) {
+            // We'll reuse the form_basic.html, but ensure we'll get the generated password autocomplete option
+            let field = doc.querySelector(props.selector);
+            if (props.type) {
+              // Change the type from 'password' to something else.
+              field.type = props.type;
+            }
+
+            field.setAttribute("autocomplete", "new-password");
+            if (props.hasOwnProperty("expectedValue")) {
+              Assert.equal(
+                field.value,
+                props.expectedValue,
+                "Check autofilled password value"
+              );
+            }
+          }
+          props = usernameProps;
+          if (props) {
+            let field = doc.querySelector(props.selector);
+            if (props.hasOwnProperty("expectedValue")) {
+              Assert.equal(
+                field.value,
+                props.expectedValue,
+                "Check autofilled username value"
+              );
+            }
+          }
+        }
+      );
+
+      if (formValues.password && formValues.password.setValue !== undefined) {
+        info(
+          "Editing the password, expectedMessage? " +
+            formValues.password.expectedMessage
+        );
+        let messagePromise = formValues.password.expectedMessage
+          ? listenForTestNotification(formValues.password.expectedMessage)
+          : Promise.resolve();
+        await changeContentInputValue(
+          browser,
+          formValues.password.selector,
+          formValues.password.setValue
+        );
+        await messagePromise;
+        info("messagePromise resolved");
+      }
+
+      if (formValues.username && formValues.username.setValue !== undefined) {
+        info(
+          "Editing the username, expectedMessage? " +
+            formValues.username.expectedMessage
+        );
+        let messagePromise = formValues.username.expectedMessage
+          ? listenForTestNotification(formValues.username.expectedMessage)
+          : Promise.resolve();
+        await changeContentInputValue(
+          browser,
+          formValues.username.selector,
+          formValues.username.setValue
+        );
+        await messagePromise;
+        info("messagePromise resolved");
+      }
+
+      await taskFn(browser);
+      await closePopup(
+        browser.ownerDocument.getElementById("confirmation-hint")
+      );
+    }
+  );
+}
+
+async function openAndVerifyDoorhanger(browser, type, expected) {
+  // check a dismissed prompt was shown with extraAttr attribute
+  let notif = getCaptureDoorhanger(type);
+  Assert.ok(notif, `${type} doorhanger was created`);
+  Assert.equal(
+    notif.dismissed,
+    expected.dismissed,
+    "Check notification dismissed property"
+  );
+  Assert.equal(
+    notif.anchorElement.getAttribute("extraAttr"),
+    expected.anchorExtraAttr,
+    "Check icon extraAttr attribute"
+  );
+  let { panel } = PopupNotifications;
+  // if the doorhanged is dimissed, we will open it to check panel contents
+  if (panel.state !== "open") {
+    let promiseShown = BrowserTestUtils.waitForEvent(panel, "popupshown");
+    if (panel.state !== "showing") {
+      // synthesize click on anchor as this also blurs the form field triggering
+      // a change event
+      EventUtils.synthesizeMouseAtCenter(notif.anchorElement, {});
+    }
+    await promiseShown;
+  }
+  let { passwordValue, usernameValue } = await checkPromptContents(
+    notif.anchorElement,
+    browser,
+    expected.passwordLength
+  );
+  Assert.equal(
+    passwordValue.length,
+    expected.passwordLength || LoginTestUtils.generation.LENGTH,
+    "Doorhanger password field has generated 15-char value"
+  );
+  Assert.equal(
+    usernameValue,
+    expected.usernameValue,
+    "Doorhanger username field was popuplated"
+  );
+  return notif;
+}
+
+async function appendContentInputvalue(browser, selector, str) {
+  await ContentTask.spawn(
+    browser,
+    { selector, str },
+    async function ({ selector, str }) {
+      const EventUtils = ContentTaskUtils.getEventUtils(content);
+      let input = content.document.querySelector(selector);
+      input.focus();
+      input.select();
+      await EventUtils.synthesizeKey("KEY_ArrowRight", {}, content);
+      let changedPromise = ContentTaskUtils.waitForEvent(input, "change");
+      if (str) {
+        await EventUtils.sendString(str, content);
+      }
+      input.blur();
+      await changedPromise;
+    }
+  );
+  info("Input value changed");
+  await TestUtils.waitForTick();
+}
+
+async function submitForm(browser) {
+  // Submit the form
+  info("Now submit the form");
+  let correctPathNamePromise = BrowserTestUtils.browserLoaded(browser);
+  await SpecialPowers.spawn(browser, [], async function () {
+    content.document.querySelector("form").submit();
+  });
+  await correctPathNamePromise;
+  await SpecialPowers.spawn(browser, [], async () => {
+    let win = content;
+    await ContentTaskUtils.waitForCondition(() => {
+      return (
+        win.location.pathname == "/" && win.document.readyState == "complete"
+      );
+    }, "Wait for form submission load");
+  });
+}
+
+add_setup(async function () {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["signon.generation.available", true],
+      ["signon.generation.enabled", true],
+    ],
+  });
+  // assert that there are no logins
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 0, "There are no logins");
+});
+
+add_task(async function autocomplete_generated_password_auto_saved() {
+  // confirm behavior when filling a generated password via autocomplete
+  // when there are no other logins
+  await setup_withNoLogins();
+  await openFormInNewTab(
+    TEST_ORIGIN + FORM_PAGE_PATH,
+    {
+      password: { selector: passwordInputSelector, expectedValue: "" },
+      username: { selector: usernameInputSelector, expectedValue: "" },
+    },
+    async function taskFn(browser) {
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "addLogin"
+      );
+      // Let the hint hide itself this first time
+      let forceClosePopup = false;
+      let hintShownAndVerified = verifyConfirmationHint(
+        browser,
+        forceClosePopup
+      );
+
+      await fillGeneratedPasswordFromACPopup(browser, passwordInputSelector);
+      let [{ username, password }] = await storageChangedPromise;
+      await verifyGeneratedPasswordWasFilled(browser, passwordInputSelector);
+
+      // Make sure confirmation hint was shown
+      info("waiting for verifyConfirmationHint");
+      await hintShownAndVerified;
+
+      // Check properties of the newly auto-saved login
+      Assert.equal(username, "", "Saved login should have no username");
+      Assert.equal(
+        password.length,
+        LoginTestUtils.generation.LENGTH,
+        "Saved login should have generated password"
+      );
+
+      let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "attention",
+        usernameValue: "",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, DONT_CHANGE_BUTTON);
+      await promiseHidden;
+
+      // confirm the extraAttr attribute is removed after opening & dismissing the doorhanger
+      Assert.ok(
+        !notif.anchorElement.hasAttribute("extraAttr"),
+        "Check if the extraAttr attribute was removed"
+      );
+      await cleanupDoorhanger(notif);
+
+      storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "modifyLogin"
+      );
+      let [autoSavedLogin] = await Services.logins.getAllLogins();
+      info("waiting for submitForm");
+      await submitForm(browser);
+      await storageChangedPromise;
+      await verifyLogins([
+        {
+          timesUsed: autoSavedLogin.timesUsed + 1,
+          username: "",
+        },
+      ]);
+    }
+  );
+});
+
+add_task(
+  async function autocomplete_generated_password_with_confirm_field_auto_saved() {
+    // confirm behavior when filling a generated password via autocomplete
+    // when there are no other logins and the form has a confirm password field
+    const FORM_WITH_CONFIRM_FIELD_PAGE_PATH =
+      "/browser/toolkit/components/passwordmgr/test/browser/form_basic_with_confirm_field.html";
+    const confirmPasswordInputSelector = "#form-basic-confirm-password";
+    await setup_withNoLogins();
+    await openFormInNewTab(
+      TEST_ORIGIN + FORM_WITH_CONFIRM_FIELD_PAGE_PATH,
+      {
+        password: { selector: passwordInputSelector, expectedValue: "" },
+        username: { selector: usernameInputSelector, expectedValue: "" },
+      },
+      async function taskFn(browser) {
+        let storageChangedPromise = TestUtils.topicObserved(
+          "passwordmgr-storage-changed",
+          (_, data) => data == "addLogin"
+        );
+        // Let the hint hide itself this first time
+        let forceClosePopup = false;
+        let hintShownAndVerified = verifyConfirmationHint(
+          browser,
+          forceClosePopup
+        );
+
+        await fillGeneratedPasswordFromACPopup(browser, passwordInputSelector);
+        let [{ username, password }] = await storageChangedPromise;
+        await verifyGeneratedPasswordWasFilled(browser, passwordInputSelector);
+        await verifyGeneratedPasswordWasFilled(
+          browser,
+          confirmPasswordInputSelector
+        );
+
+        // Make sure confirmation hint was shown
+        info("waiting for verifyConfirmationHint");
+        await hintShownAndVerified;
+
+        // Check properties of the newly auto-saved login
+        Assert.equal(username, "", "Saved login should have no username");
+        Assert.equal(
+          password.length,
+          LoginTestUtils.generation.LENGTH,
+          "Saved login should have generated password"
+        );
+
+        let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+          dismissed: true,
+          anchorExtraAttr: "attention",
+          usernameValue: "",
+          passwordLength: LoginTestUtils.generation.LENGTH,
+        });
+
+        let promiseHidden = BrowserTestUtils.waitForEvent(
+          PopupNotifications.panel,
+          "popuphidden"
+        );
+        clickDoorhangerButton(notif, DONT_CHANGE_BUTTON);
+        await promiseHidden;
+
+        // confirm the extraAttr attribute is removed after opening & dismissing the doorhanger
+        Assert.ok(
+          !notif.anchorElement.hasAttribute("extraAttr"),
+          "Check if the extraAttr attribute was removed"
+        );
+        await cleanupDoorhanger(notif);
+
+        storageChangedPromise = TestUtils.topicObserved(
+          "passwordmgr-storage-changed",
+          (_, data) => data == "modifyLogin"
+        );
+        let [autoSavedLogin] = await Services.logins.getAllLogins();
+        info("waiting for submitForm");
+        await submitForm(browser);
+        await storageChangedPromise;
+        await verifyLogins([
+          {
+            timesUsed: autoSavedLogin.timesUsed + 1,
+            username: "",
+          },
+        ]);
+      }
+    );
+  }
+);
+
+add_task(async function autocomplete_generated_password_saved_empty_username() {
+  // confirm behavior when filling a generated password via autocomplete
+  // when there is an existing saved login with a "" username
+  await setup_withOneLogin("", "xyzpassword");
+  await openFormInNewTab(
+    TEST_ORIGIN + FORM_PAGE_PATH,
+    {
+      password: {
+        selector: passwordInputSelector,
+        expectedValue: "xyzpassword",
+        setValue: "",
+        expectedMessage: "PasswordEditedOrGenerated",
+      },
+      username: { selector: usernameInputSelector, expectedValue: "" },
+    },
+    async function taskFn(browser) {
+      let [savedLogin] = await Services.logins.getAllLogins();
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "modifyLogin"
+      );
+      await fillGeneratedPasswordFromACPopup(browser, passwordInputSelector);
+      await waitForDoorhanger(browser, "password-change");
+      info("Waiting to openAndVerifyDoorhanger");
+      await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "",
+        usernameValue: "",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+      await hideDoorhangerPopup();
+      info("Waiting to verifyGeneratedPasswordWasFilled");
+      await verifyGeneratedPasswordWasFilled(browser, passwordInputSelector);
+
+      info("waiting for submitForm");
+      await submitForm(browser);
+      let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: false,
+        anchorExtraAttr: "",
+        usernameValue: "",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+      await promiseHidden;
+
+      info("Waiting for modifyLogin");
+      await storageChangedPromise;
+      await verifyLogins([
+        {
+          timesUsed: savedLogin.timesUsed + 1,
+          username: "",
+        },
+      ]);
+      await cleanupDoorhanger(notif); // cleanup the doorhanger for next test
+    }
+  );
+});
+
+add_task(async function autocomplete_generated_password_saved_username() {
+  // confirm behavior when filling a generated password via autocomplete
+  // into a form with username matching an existing saved login
+  await setup_withOneLogin("user1", "xyzpassword");
+  await openFormInNewTab(
+    TEST_ORIGIN + FORM_PAGE_PATH,
+    {
+      password: {
+        selector: passwordInputSelector,
+        expectedValue: "xyzpassword",
+        setValue: "",
+        expectedMessage: "PasswordEditedOrGenerated",
+      },
+      username: {
+        selector: usernameInputSelector,
+        expectedValue: "user1",
+      },
+    },
+    async function taskFn(browser) {
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "addLogin"
+      );
+      // We don't need to wait to confirm the hint hides itelf every time
+      let forceClosePopup = true;
+      let hintShownAndVerified = verifyConfirmationHint(
+        browser,
+        forceClosePopup
+      );
+
+      await fillGeneratedPasswordFromACPopup(browser, passwordInputSelector);
+
+      // Make sure confirmation hint was shown
+      info("waiting for verifyConfirmationHint");
+      await hintShownAndVerified;
+
+      info("waiting for addLogin");
+      await storageChangedPromise;
+      await verifyGeneratedPasswordWasFilled(browser, passwordInputSelector);
+
+      // Check properties of the newly auto-saved login
+      let [user1LoginSnapshot, autoSavedLogin] = await verifyLogins([
+        {
+          username: "user1",
+          password: "xyzpassword", // user1 is unchanged
+        },
+        {
+          timesUsed: 1,
+          username: "",
+          passwordLength: LoginTestUtils.generation.LENGTH,
+        },
+      ]);
+
+      let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "attention",
+        usernameValue: "user1",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, DONT_CHANGE_BUTTON);
+      await promiseHidden;
+
+      // confirm the extraAttr attribute is removed after opening & dismissing the doorhanger
+      Assert.ok(
+        !notif.anchorElement.hasAttribute("extraAttr"),
+        "Check if the extraAttr attribute was removed"
+      );
+      await cleanupDoorhanger(notif);
+
+      storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "modifyLogin"
+      );
+      info("waiting for submitForm");
+      await submitForm(browser);
+      promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+      await promiseHidden;
+      await storageChangedPromise;
+      await verifyLogins([
+        {
+          timesUsed: user1LoginSnapshot.timesUsed + 1,
+          username: "user1",
+          password: autoSavedLogin.password,
+        },
+      ]);
+    }
+  );
+});
+
+add_task(async function ac_gen_pw_saved_empty_un_stored_non_empty_un_in_form() {
+  // confirm behavior when when the form's username field has a non-empty value
+  // and there is an existing saved login with a "" username
+  await setup_withOneLogin("", "xyzpassword");
+  await openFormInNewTab(
+    TEST_ORIGIN + FORM_PAGE_PATH,
+    {
+      password: {
+        selector: passwordInputSelector,
+        expectedValue: "xyzpassword",
+        setValue: "",
+        expectedMessage: "PasswordEditedOrGenerated",
+      },
+      username: {
+        selector: usernameInputSelector,
+        expectedValue: "",
+        setValue: "myusername",
+        // with an empty password value, no message is sent for a username change
+        expectedMessage: "",
+      },
+    },
+    async function taskFn(browser) {
+      let [savedLogin] = await Services.logins.getAllLogins();
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "addLogin"
+      );
+      await fillGeneratedPasswordFromACPopup(browser, passwordInputSelector);
+      await waitForDoorhanger(browser, "password-save");
+      info("Waiting to openAndVerifyDoorhanger");
+      await openAndVerifyDoorhanger(browser, "password-save", {
+        dismissed: true,
+        anchorExtraAttr: "",
+        usernameValue: "myusername",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+      await hideDoorhangerPopup();
+      info("Waiting to verifyGeneratedPasswordWasFilled");
+      await verifyGeneratedPasswordWasFilled(browser, passwordInputSelector);
+
+      info("waiting for submitForm");
+      await submitForm(browser);
+      let notif = await openAndVerifyDoorhanger(browser, "password-save", {
+        dismissed: false,
+        anchorExtraAttr: "",
+        usernameValue: "myusername",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, REMEMBER_BUTTON);
+      await promiseHidden;
+
+      info("Waiting for addLogin");
+      await storageChangedPromise;
+      await verifyLogins([
+        {
+          timesUsed: savedLogin.timesUsed,
+          username: "",
+          password: "xyzpassword",
+        },
+        {
+          timesUsed: 1,
+          username: "myusername",
+        },
+      ]);
+      await cleanupDoorhanger(notif); // cleanup the doorhanger for next test
+    }
+  );
+});
+
+add_task(async function contextfill_generated_password_saved_empty_username() {
+  // confirm behavior when filling a generated password via context menu
+  // when there is an existing saved login with a "" username
+  await setup_withOneLogin("", "xyzpassword");
+  await openFormInNewTab(
+    TEST_ORIGIN + FORM_PAGE_PATH,
+    {
+      password: {
+        selector: passwordInputSelector,
+        expectedValue: "xyzpassword",
+        setValue: "",
+        expectedMessage: "PasswordEditedOrGenerated",
+      },
+      username: { selector: usernameInputSelector, expectedValue: "" },
+    },
+    async function taskFn(browser) {
+      let [savedLogin] = await Services.logins.getAllLogins();
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "modifyLogin"
+      );
+      await doFillGeneratedPasswordContextMenuItem(
+        browser,
+        passwordInputSelector
+      );
+      await waitForDoorhanger(browser, "password-change");
+      info("Waiting to openAndVerifyDoorhanger");
+      await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "",
+        usernameValue: "",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+      await hideDoorhangerPopup();
+      info("Waiting to verifyGeneratedPasswordWasFilled");
+      await verifyGeneratedPasswordWasFilled(browser, passwordInputSelector);
+
+      info("waiting for submitForm");
+      await submitForm(browser);
+      let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: false,
+        anchorExtraAttr: "",
+        usernameValue: "",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+      await promiseHidden;
+
+      info("Waiting for modifyLogin");
+      await storageChangedPromise;
+      await verifyLogins([
+        {
+          timesUsed: savedLogin.timesUsed + 1,
+          username: "",
+        },
+      ]);
+      await cleanupDoorhanger(notif); // cleanup the doorhanger for next test
+    }
+  );
+});
+
+async function autocomplete_generated_password_edited_no_auto_save(
+  passwordType = "password"
+) {
+  // confirm behavior when filling a generated password via autocomplete
+  // when there is an existing saved login with a "" username and then editing
+  // the password and autocompleting again.
+  await setup_withOneLogin("", "xyzpassword");
+  await openFormInNewTab(
+    TEST_ORIGIN + FORM_PAGE_PATH,
+    {
+      password: {
+        selector: passwordInputSelector,
+        expectedValue: "xyzpassword",
+        setValue: "",
+        type: passwordType,
+        expectedMessage: "PasswordEditedOrGenerated",
+      },
+      username: { selector: usernameInputSelector, expectedValue: "" },
+    },
+    async function taskFn(browser) {
+      let [savedLogin] = await Services.logins.getAllLogins();
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "modifyLogin"
+      );
+      await fillGeneratedPasswordFromACPopup(browser, passwordInputSelector);
+      info(
+        "Filled generated password, waiting for dismissed password-change doorhanger"
+      );
+      await waitForDoorhanger(browser, "password-change");
+      info("Waiting to openAndVerifyDoorhanger");
+      let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "",
+        usernameValue: "",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, DONT_CHANGE_BUTTON);
+      await promiseHidden;
+
+      info("Waiting to verifyGeneratedPasswordWasFilled");
+      await verifyGeneratedPasswordWasFilled(browser, passwordInputSelector);
+
+      await BrowserTestUtils.sendChar("!", browser);
+      await BrowserTestUtils.sendChar("@", browser);
+      await BrowserTestUtils.synthesizeKey("KEY_Tab", undefined, browser);
+
+      await waitForDoorhanger(browser, "password-change");
+      info("Waiting to openAndVerifyDoorhanger");
+      notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "",
+        usernameValue: "",
+        passwordLength: LoginTestUtils.generation.LENGTH + 2,
+      });
+
+      promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, DONT_CHANGE_BUTTON);
+      await promiseHidden;
+
+      await verifyLogins([
+        {
+          timesUsed: savedLogin.timesUsed,
+          username: "",
+          password: "xyzpassword",
+        },
+      ]);
+
+      info("waiting for submitForm");
+      await submitForm(browser);
+      notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: false,
+        anchorExtraAttr: "",
+        usernameValue: "",
+        passwordLength: LoginTestUtils.generation.LENGTH + 2,
+      });
+
+      promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+      await promiseHidden;
+
+      info("Waiting for modifyLogin");
+      await storageChangedPromise;
+      await verifyLogins([
+        {
+          timesUsed: savedLogin.timesUsed + 1,
+          username: "",
+        },
+      ]);
+      await cleanupDoorhanger(notif); // cleanup the doorhanger for next test
+    }
+  );
+
+  LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+}
+
+add_task(autocomplete_generated_password_edited_no_auto_save);
+
+add_task(
+  async function autocomplete_generated_password_edited_no_auto_save_type_text() {
+    await autocomplete_generated_password_edited_no_auto_save("text");
+  }
+);
+
+add_task(async function contextmenu_fill_generated_password_and_set_username() {
+  // test when filling with a generated password and editing the username in the form
+  // * the prompt should display the form's username
+  // * the auto-saved login should have "" for username
+  // * confirming the prompt should edit the "" login and add the username
+  await setup_withOneLogin("olduser", "xyzpassword");
+  await openFormInNewTab(
+    TEST_ORIGIN + FORM_PAGE_PATH,
+    {
+      password: {
+        selector: passwordInputSelector,
+        expectedValue: "xyzpassword",
+        setValue: "",
+        expectedMessage: "PasswordEditedOrGenerated",
+      },
+      username: {
+        selector: usernameInputSelector,
+        expectedValue: "olduser",
+        setValue: "differentuser",
+        // with an empty password value, no message is sent for a username change
+        expectedMessage: "",
+      },
+    },
+    async function taskFn(browser) {
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "addLogin"
+      );
+      await SpecialPowers.spawn(
+        browser,
+        [[passwordInputSelector, usernameInputSelector]],
+        function checkEmptyPasswordField([passwordSelector, usernameSelector]) {
+          Assert.equal(
+            content.document.querySelector(passwordSelector).value,
+            "",
+            "Password field is empty"
+          );
+        }
+      );
+
+      // Let the hint hide itself this first time
+      let forceClosePopup = false;
+      let hintShownAndVerified = verifyConfirmationHint(
+        browser,
+        forceClosePopup
+      );
+
+      info("waiting to fill generated password using context menu");
+      await doFillGeneratedPasswordContextMenuItem(
+        browser,
+        passwordInputSelector
+      );
+
+      info("waiting for verifyConfirmationHint");
+      await hintShownAndVerified;
+      info("waiting for dismissed password-change notification");
+      await waitForDoorhanger(browser, "password-change");
+
+      info("waiting for addLogin");
+      await storageChangedPromise;
+
+      // Check properties of the newly auto-saved login
+      await verifyLogins([
+        null, // ignore the first one
+        {
+          timesUsed: 1,
+          username: "",
+          passwordLength: LoginTestUtils.generation.LENGTH,
+        },
+      ]);
+
+      info("Waiting to openAndVerifyDoorhanger");
+      await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "attention",
+        usernameValue: "differentuser",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+      await hideDoorhangerPopup();
+      info("Waiting to verifyGeneratedPasswordWasFilled");
+      await verifyGeneratedPasswordWasFilled(browser, passwordInputSelector);
+
+      info("waiting for submitForm");
+      await submitForm(browser);
+      let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: false,
+        anchorExtraAttr: "",
+        usernameValue: "differentuser",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+
+      storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "modifyLogin"
+      );
+
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+      await promiseHidden;
+
+      info("Waiting for modifyLogin");
+      await storageChangedPromise;
+      await verifyLogins([
+        null,
+        {
+          username: "differentuser",
+          passwordLength: LoginTestUtils.generation.LENGTH,
+          timesUsed: 2,
+        },
+      ]);
+      await cleanupDoorhanger(notif); // cleanup the doorhanger for next test
+    }
+  );
+});
+
+add_task(async function contextmenu_password_change_form_without_username() {
+  // test doorhanger behavior when a generated password is filled into a change-password
+  // form with no username
+  await setup_withOneLogin("user1", "xyzpassword");
+  await LoginTestUtils.addLogin({ username: "username2", password: "pass2" });
+  const passwordInputSelector = "#newpass";
+
+  const CHANGE_FORM_PATH =
+    "/browser/toolkit/components/passwordmgr/test/browser/form_password_change.html";
+  await openFormInNewTab(
+    TEST_ORIGIN + CHANGE_FORM_PATH,
+    {
+      password: {
+        selector: passwordInputSelector,
+        expectedValue: "",
+      },
+    },
+    async function taskFn(browser) {
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "addLogin"
+      );
+
+      // We don't need to wait to confirm the hint hides itelf every time
+      let forceClosePopup = true;
+      let hintShownAndVerified = verifyConfirmationHint(
+        browser,
+        forceClosePopup
+      );
+
+      // Make the 2nd field use a generated password
+      info("Using contextmenu to fill with a generated password");
+      await doFillGeneratedPasswordContextMenuItem(
+        browser,
+        passwordInputSelector
+      );
+
+      info("waiting for dismissed password-change notification");
+      await waitForDoorhanger(browser, "password-change");
+
+      // Make sure confirmation hint was shown
+      info("waiting for verifyConfirmationHint");
+      await hintShownAndVerified;
+
+      info("waiting for addLogin");
+      await storageChangedPromise;
+      // Check properties of the newly auto-saved login
+      await verifyLogins([
+        null, // ignore the first one
+        null, // ignore the 2nd one
+        {
+          timesUsed: 1,
+          username: "",
+          passwordLength: LoginTestUtils.generation.LENGTH,
+        },
+      ]);
+
+      info("Waiting to openAndVerifyDoorhanger");
+      let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "attention",
+        usernameValue: "",
+        passwordLength: LoginTestUtils.generation.LENGTH,
+      });
+      // remove notification so we can unambiguously check no new notification gets created later
+      await cleanupDoorhanger(notif);
+
+      info("Waiting to verifyGeneratedPasswordWasFilled");
+      await verifyGeneratedPasswordWasFilled(browser, passwordInputSelector);
+
+      storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "modifyLogin"
+      );
+      let { timeLastUsed } = (await Services.logins.getAllLogins())[2];
+
+      info("waiting for submitForm");
+      await submitForm(browser);
+
+      info("Waiting for modifyLogin");
+      await storageChangedPromise;
+      await verifyLogins([
+        null, // ignore the first one
+        null, // ignore the 2nd one
+        {
+          timesUsed: 2,
+          usedSince: timeLastUsed,
+        },
+      ]);
+      // Check no new doorhanger was shown
+      notif = getCaptureDoorhanger("password-change");
+      Assert.ok(!notif, "No new doorhanger should be shown");
+      await cleanupDoorhanger(); // cleanup for next test
+    }
+  );
+});
+
+add_task(
+  async function autosaved_login_updated_to_existing_login_via_doorhanger() {
+    // test when filling with a generated password and editing the username in the
+    // doorhanger to match an existing login:
+    // * the matching login should be updated
+    // * the auto-saved login should be deleted
+    // * the metadata for the matching login should be updated
+    // * the by-origin cache for the password should point at the updated login
+    await setup_withOneLogin("user1", "xyzpassword");
+    await LoginTestUtils.addLogin({
+      username: "user2",
+      password: "abcpassword",
+    });
+    await openFormInNewTab(
+      TEST_ORIGIN + FORM_PAGE_PATH,
+      {
+        password: {
+          selector: passwordInputSelector,
+          expectedValue: "",
+        },
+        username: {
+          selector: usernameInputSelector,
+          expectedValue: "",
+        },
+      },
+      async function taskFn(browser) {
+        await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+        let storageChangedPromise = TestUtils.topicObserved(
+          "passwordmgr-storage-changed",
+          (_, data) => data == "addLogin"
+        );
+        // We don't need to wait to confirm the hint hides itelf every time
+        let forceClosePopup = true;
+        let hintShownAndVerified = verifyConfirmationHint(
+          browser,
+          forceClosePopup
+        );
+
+        info("waiting to fill generated password using context menu");
+        await doFillGeneratedPasswordContextMenuItem(
+          browser,
+          passwordInputSelector
+        );
+
+        info("waiting for dismissed password-change notification");
+        await waitForDoorhanger(browser, "password-change");
+
+        // Make sure confirmation hint was shown
+        info("waiting for verifyConfirmationHint");
+        await hintShownAndVerified;
+
+        info("waiting for addLogin");
+        await storageChangedPromise;
+        info("addLogin promise resolved");
+        // Check properties of the newly auto-saved login
+        let [user1LoginSnapshot, unused, autoSavedLogin] = await verifyLogins([
+          null, // ignore the first one
+          null, // ignore the 2nd one
+          {
+            timesUsed: 1,
+            username: "",
+            passwordLength: LoginTestUtils.generation.LENGTH,
+          },
+        ]);
+        info("user1LoginSnapshot, guid: " + user1LoginSnapshot.guid);
+        info("unused, guid: " + unused.guid);
+        info("autoSavedLogin, guid: " + autoSavedLogin.guid);
+
+        info("verifyLogins ok");
+        let passwordCacheEntry =
+          LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+            "https://example.com"
+          );
+
+        Assert.ok(
+          passwordCacheEntry,
+          "Got the cached generated password entry for https://example.com"
+        );
+        Assert.equal(
+          passwordCacheEntry.value,
+          autoSavedLogin.password,
+          "Cached password matches the auto-saved login password"
+        );
+        Assert.equal(
+          passwordCacheEntry.storageGUID,
+          autoSavedLogin.guid,
+          "Cached password guid matches the auto-saved login guid"
+        );
+
+        info("Waiting to openAndVerifyDoorhanger");
+        let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+          dismissed: true,
+          anchorExtraAttr: "attention",
+          usernameValue: "",
+          password: autoSavedLogin.password,
+        });
+        Assert.ok(notif, "Got password-change notification");
+
+        info("Calling updateDoorhangerInputValues");
+        await updateDoorhangerInputValues({
+          username: "user1",
+        });
+        info("doorhanger inputs updated");
+
+        let loginModifiedPromise = TestUtils.topicObserved(
+          "passwordmgr-storage-changed",
+          (subject, data) => {
+            if (data == "modifyLogin") {
+              info("passwordmgr-storage-changed, action: " + data);
+              info("subject: " + JSON.stringify(subject));
+              return true;
+            }
+            return false;
+          }
+        );
+        let loginRemovedPromise = TestUtils.topicObserved(
+          "passwordmgr-storage-changed",
+          (subject, data) => {
+            if (data == "removeLogin") {
+              info("passwordmgr-storage-changed, action: " + data);
+              info("subject: " + JSON.stringify(subject));
+              return true;
+            }
+            return false;
+          }
+        );
+
+        let promiseHidden = BrowserTestUtils.waitForEvent(
+          PopupNotifications.panel,
+          "popuphidden"
+        );
+        info("clicking change button");
+        clickDoorhangerButton(notif, CHANGE_BUTTON);
+        await promiseHidden;
+
+        info("Waiting for modifyLogin promise");
+        await loginModifiedPromise;
+
+        info("Waiting for removeLogin promise");
+        await loginRemovedPromise;
+
+        info("storage-change promises resolved");
+        // Check the auto-saved login was removed and the original login updated
+        await verifyLogins([
+          {
+            username: "user1",
+            password: autoSavedLogin.password,
+            timeCreated: user1LoginSnapshot.timeCreated,
+            timeLastUsed: user1LoginSnapshot.timeLastUsed,
+            passwordChangedSince: autoSavedLogin.timePasswordChanged,
+          },
+          null, // ignore user2
+        ]);
+
+        // Check we have no notifications at this point
+        Assert.ok(!PopupNotifications.isPanelOpen, "No doorhanger is open");
+        Assert.ok(
+          !PopupNotifications.getNotification("password", browser),
+          "No notifications"
+        );
+
+        // make sure the cache entry is unchanged with the removal of the auto-saved login
+        Assert.equal(
+          autoSavedLogin.password,
+          LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+            "https://example.com"
+          ).value,
+          "Generated password cache entry has the expected password value"
+        );
+      }
+    );
+  }
+);
+
+add_task(async function autosaved_login_updated_to_existing_login_onsubmit() {
+  // test when selecting auto-saved generated password in a form filled with an
+  // existing login and submitting the form:
+  // * the matching login should be updated
+  // * the auto-saved login should be deleted
+  // * the metadata for the matching login should be updated
+  // * the by-origin cache for the password should point at the updated login
+
+  // clear both fields which should be autofilled with our single login
+  await setup_withOneLogin("user1", "xyzpassword");
+  await openFormInNewTab(
+    TEST_ORIGIN + FORM_PAGE_PATH,
+    {
+      password: {
+        selector: passwordInputSelector,
+        expectedValue: "xyzpassword",
+        setValue: "",
+        expectedMessage: "PasswordEditedOrGenerated",
+      },
+      username: {
+        selector: usernameInputSelector,
+        expectedValue: "user1",
+        setValue: "",
+        // with an empty password value, no message is sent for a username change
+        expectedMessage: "",
+      },
+    },
+    async function taskFn(browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+      // first, create an auto-saved login with generated password
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "addLogin"
+      );
+      // We don't need to wait to confirm the hint hides itelf every time
+      let forceClosePopup = true;
+      let hintShownAndVerified = verifyConfirmationHint(
+        browser,
+        forceClosePopup
+      );
+
+      info("waiting to fill generated password using context menu");
+      await doFillGeneratedPasswordContextMenuItem(
+        browser,
+        passwordInputSelector
+      );
+
+      info("waiting for dismissed password-change notification");
+      await waitForDoorhanger(browser, "password-change");
+
+      // Make sure confirmation hint was shown
+      info("waiting for verifyConfirmationHint");
+      await hintShownAndVerified;
+
+      info("waiting for addLogin");
+      await storageChangedPromise;
+      info("addLogin promise resolved");
+      // Check properties of the newly auto-saved login
+      let [user1LoginSnapshot, autoSavedLogin] = await verifyLogins([
+        null, // ignore the first one
+        {
+          timesUsed: 1,
+          username: "",
+          passwordLength: LoginTestUtils.generation.LENGTH,
+        },
+      ]);
+      info("user1LoginSnapshot, guid: " + user1LoginSnapshot.guid);
+      info("autoSavedLogin, guid: " + autoSavedLogin.guid);
+
+      info("verifyLogins ok");
+      let passwordCacheEntry =
+        LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+          "https://example.com"
+        );
+
+      Assert.ok(
+        passwordCacheEntry,
+        "Got the cached generated password entry for https://example.com"
+      );
+      Assert.equal(
+        passwordCacheEntry.value,
+        autoSavedLogin.password,
+        "Cached password matches the auto-saved login password"
+      );
+      Assert.equal(
+        passwordCacheEntry.storageGUID,
+        autoSavedLogin.guid,
+        "Cached password guid matches the auto-saved login guid"
+      );
+
+      let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "attention",
+        usernameValue: "",
+        password: autoSavedLogin.password,
+      });
+      await cleanupDoorhanger(notif);
+
+      // now update and submit the form with the user1 username and the generated password
+      info(`submitting form`);
+      let submitResults = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {
+          "#form-basic-username": "user1",
+        }
+      );
+      Assert.equal(
+        submitResults.username,
+        "user1",
+        "Form submitted with expected username"
+      );
+      Assert.equal(
+        submitResults.password,
+        autoSavedLogin.password,
+        "Form submitted with expected password"
+      );
+      info(
+        `form was submitted, got username/password ${submitResults.username}/${submitResults.password}`
+      );
+
+      await waitForDoorhanger(browser, "password-change");
+      notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: false,
+        anchorExtraAttr: "",
+        usernameValue: "user1",
+        password: autoSavedLogin.password,
+      });
+
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      let loginModifiedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => {
+          if (data == "modifyLogin") {
+            info("passwordmgr-storage-changed, action: " + data);
+            info("subject: " + JSON.stringify(_));
+            return true;
+          }
+          return false;
+        }
+      );
+      let loginRemovedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => {
+          if (data == "removeLogin") {
+            info("passwordmgr-storage-changed, action: " + data);
+            info("subject: " + JSON.stringify(_));
+            return true;
+          }
+          return false;
+        }
+      );
+
+      info("clicking change button");
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+      await promiseHidden;
+
+      info("Waiting for modifyLogin promise");
+      await loginModifiedPromise;
+
+      info("Waiting for removeLogin promise");
+      await loginRemovedPromise;
+
+      info("storage-change promises resolved");
+      // Check the auto-saved login was removed and the original login updated
+      await verifyLogins([
+        {
+          username: "user1",
+          password: autoSavedLogin.password,
+          timeCreated: user1LoginSnapshot.timeCreated,
+          timeLastUsed: user1LoginSnapshot.timeLastUsed,
+          passwordChangedSince: autoSavedLogin.timePasswordChanged,
+        },
+      ]);
+
+      // Check we have no notifications at this point
+      Assert.ok(!PopupNotifications.isPanelOpen, "No doorhanger is open");
+      Assert.ok(
+        !PopupNotifications.getNotification("password", browser),
+        "No notifications"
+      );
+
+      // make sure the cache entry is unchanged with the removal of the auto-saved login
+      Assert.equal(
+        autoSavedLogin.password,
+        LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+          "https://example.com"
+        ).value,
+        "Generated password cache entry has the expected password value"
+      );
+    }
+  );
+});
+
+add_task(async function form_change_from_autosaved_login_to_existing_login() {
+  // test when changing from a generated password in a form to an existing saved login
+  // * the auto-saved login should not be deleted
+  // * the metadata for the matching login should be updated
+  // * the by-origin cache for the password should point at the autosaved login
+
+  await setup_withOneLogin("user1", "xyzpassword");
+  await openFormInNewTab(
+    TEST_ORIGIN + FORM_PAGE_PATH,
+    {
+      password: {
+        selector: passwordInputSelector,
+        expectedValue: "xyzpassword",
+        setValue: "",
+        expectedMessage: "PasswordEditedOrGenerated",
+      },
+      username: {
+        selector: usernameInputSelector,
+        expectedValue: "user1",
+        setValue: "",
+        // with an empty password value, no message is sent for a username change
+        expectedMessage: "",
+      },
+    },
+    async function taskFn(browser) {
+      await SimpleTest.promiseFocus(browser);
+
+      // first, create an auto-saved login with generated password
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "addLogin"
+      );
+      // We don't need to wait to confirm the hint hides itelf every time
+      let forceClosePopup = true;
+      let hintShownAndVerified = verifyConfirmationHint(
+        browser,
+        forceClosePopup
+      );
+
+      info("Filling generated password from AC menu");
+      await fillGeneratedPasswordFromACPopup(browser, passwordInputSelector);
+
+      info("waiting for dismissed password-change notification");
+      await waitForDoorhanger(browser, "password-change");
+
+      // Make sure confirmation hint was shown
+      info("waiting for verifyConfirmationHint");
+      await hintShownAndVerified;
+
+      info("waiting for addLogin");
+      await storageChangedPromise;
+      info("addLogin promise resolved");
+      // Check properties of the newly auto-saved login
+      let [user1LoginSnapshot, autoSavedLogin] = await verifyLogins([
+        null, // ignore the first one
+        {
+          timesUsed: 1,
+          username: "",
+          passwordLength: LoginTestUtils.generation.LENGTH,
+        },
+      ]);
+      info("user1LoginSnapshot, guid: " + user1LoginSnapshot.guid);
+      info("autoSavedLogin, guid: " + autoSavedLogin.guid);
+
+      info("verifyLogins ok");
+      let passwordCacheEntry =
+        LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+          "https://example.com"
+        );
+
+      Assert.ok(
+        passwordCacheEntry,
+        "Got the cached generated password entry for https://example.com"
+      );
+      Assert.equal(
+        passwordCacheEntry.value,
+        autoSavedLogin.password,
+        "Cached password matches the auto-saved login password"
+      );
+      Assert.equal(
+        passwordCacheEntry.storageGUID,
+        autoSavedLogin.guid,
+        "Cached password guid matches the auto-saved login guid"
+      );
+
+      let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "attention",
+        usernameValue: "",
+        password: autoSavedLogin.password,
+      });
+
+      // close but don't remove the doorhanger, we want to ensure it is updated/replaced on further form edits
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      let PN = notif.owner;
+      PN.panel.hidePopup();
+      await promiseHidden;
+      await TestUtils.waitForTick();
+
+      // now update the form with the user1 username and password
+      info(`updating form`);
+      let passwordEditedMessages = listenForTestNotification(
+        "PasswordEditedOrGenerated",
+        2
+      );
+      let passwordChangeDoorhangerPromise = waitForDoorhanger(
+        browser,
+        "password-change"
+      );
+      let hintDidShow = false;
+      let hintPromiseShown = BrowserTestUtils.waitForPopupEvent(
+        document.getElementById("confirmation-hint"),
+        "shown"
+      );
+      hintPromiseShown.then(() => (hintDidShow = true));
+
+      info("Entering username and password for the previously saved login");
+
+      await changeContentFormValues(browser, {
+        [passwordInputSelector]: user1LoginSnapshot.password,
+        [usernameInputSelector]: user1LoginSnapshot.username,
+      });
+      info(
+        "form edited, waiting for test notification of PasswordEditedOrGenerated"
+      );
+
+      await passwordEditedMessages;
+      info("Resolved listenForTestNotification promise");
+
+      await passwordChangeDoorhangerPromise;
+      // wait to ensure there's no confirmation hint
+      try {
+        await TestUtils.waitForCondition(
+          () => {
+            return hintDidShow;
+          },
+          `Waiting for confirmationHint popup`,
+          undefined,
+          25
+        );
+      } catch (ex) {
+        info("Got expected timeout from the waitForCondition: ", ex);
+      } finally {
+        Assert.ok(!hintDidShow, "No confirmation hint shown");
+      }
+
+      // the previous doorhanger would have old values, verify it was updated/replaced with new values from the form
+      notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "",
+        usernameValue: user1LoginSnapshot.username,
+        passwordLength: user1LoginSnapshot.password.length,
+      });
+      await cleanupDoorhanger(notif);
+
+      storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "modifyLogin"
+      );
+
+      // submit the form to ensure the correct updates are made
+      await submitForm(browser);
+      info("form submitted, waiting for storage changed");
+      await storageChangedPromise;
+
+      // Check the auto-saved login has not changed and only metadata on the original login updated
+      await verifyLogins([
+        {
+          username: "user1",
+          password: "xyzpassword",
+          timeCreated: user1LoginSnapshot.timeCreated,
+          usedSince: user1LoginSnapshot.timeLastUsed,
+        },
+        {
+          username: "",
+          password: autoSavedLogin.password,
+          timeCreated: autoSavedLogin.timeCreated,
+          timeLastUsed: autoSavedLogin.timeLastUsed,
+        },
+      ]);
+
+      // Check we have no notifications at this point
+      Assert.ok(!PopupNotifications.isPanelOpen, "No doorhanger is open");
+      Assert.ok(
+        !PopupNotifications.getNotification("password", browser),
+        "No notifications"
+      );
+
+      // make sure the cache entry is unchanged with the removal of the auto-saved login
+      Assert.equal(
+        autoSavedLogin.password,
+        LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+          "https://example.com"
+        ).value,
+        "Generated password cache entry has the expected password value"
+      );
+    }
+  );
+});
+
+add_task(async function form_edit_username_and_password_of_generated_login() {
+  // test when changing the username and then the password in a form with a generated password (bug 1625242)
+  // * the toast is not shown for the username change as the auto-saved login is not modified
+  // * the dismissed doorhanger for the username change has the correct username and password
+  // * the toast is shown for the change to the generated password
+  // * the dismissed doorhanger for the password change has the correct username and password
+
+  await setup_withNoLogins();
+  await openFormInNewTab(
+    TEST_ORIGIN + FORM_PAGE_PATH,
+    {},
+    async function taskFn(browser) {
+      await SimpleTest.promiseFocus(browser);
+
+      // first, create an auto-saved login with generated password
+      let storageChangedPromise = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == "addLogin"
+      );
+      // We don't need to wait to confirm the hint hides itelf every time
+      let forceClosePopup = true;
+      let hintShownAndVerified = verifyConfirmationHint(
+        browser,
+        forceClosePopup
+      );
+
+      info("Filling generated password from context menu");
+      // there's no new-password field in this form so we'll use the context menu
+      await doFillGeneratedPasswordContextMenuItem(
+        browser,
+        passwordInputSelector
+      );
+
+      info("waiting for dismissed password-change notification");
+      await waitForDoorhanger(browser, "password-change");
+
+      // Make sure confirmation hint was shown
+      info("waiting for verifyConfirmationHint");
+      await hintShownAndVerified;
+
+      info("waiting for addLogin");
+      await storageChangedPromise;
+      info("addLogin promise resolved");
+      // Check properties of the newly auto-saved login
+      let [autoSavedLoginSnapshot] = await verifyLogins([
+        {
+          timesUsed: 1,
+          username: "",
+          passwordLength: LoginTestUtils.generation.LENGTH,
+        },
+      ]);
+
+      let notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: true,
+        anchorExtraAttr: "attention",
+        usernameValue: "",
+        password: autoSavedLoginSnapshot.password,
+      });
+
+      // close but don't remove the doorhanger, we want to ensure it is updated/replaced on further form edits
+      let promiseHidden = BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popuphidden"
+      );
+      let PN = notif.owner;
+      PN.panel.hidePopup();
+      await promiseHidden;
+      await TestUtils.waitForTick();
+
+      // change the username then the password in the form
+      for (let {
+        fieldSelector,
+        fieldValue,
+        expectedConfirmation,
+        expectedDoorhangerUsername,
+        expectedDoorhangerPassword,
+        expectedDoorhangerType,
+      } of [
+        {
+          fieldSelector: usernameInputSelector,
+          fieldValue: "someuser",
+          expectedConfirmation: false,
+          expectedDoorhangerUsername: "someuser",
+          expectedDoorhangerPassword: autoSavedLoginSnapshot.password,
+          expectedDoorhangerType: "password-change",
+        },
+        {
+          fieldSelector: passwordInputSelector,
+          fieldValue: "!!",
+          expectedConfirmation: true,
+          expectedDoorhangerUsername: "someuser",
+          expectedDoorhangerPassword: autoSavedLoginSnapshot.password + "!!",
+          expectedDoorhangerType: "password-change",
+        },
+      ]) {
+        let loginModifiedPromise = expectedConfirmation
+          ? TestUtils.topicObserved(
+              "passwordmgr-storage-changed",
+              (_, data) => data == "modifyLogin"
+            )
+          : Promise.resolve();
+
+        // now edit the field value
+        let passwordEditedMessage = listenForTestNotification(
+          "PasswordEditedOrGenerated"
+        );
+        let passwordChangeDoorhangerPromise = waitForDoorhanger(
+          browser,
+          expectedDoorhangerType
+        );
+        let hintDidShow = false;
+        let hintPromiseShown = BrowserTestUtils.waitForPopupEvent(
+          document.getElementById("confirmation-hint"),
+          "shown"
+        );
+        hintPromiseShown.then(() => (hintDidShow = true));
+
+        info(`updating form: ${fieldSelector}: ${fieldValue}`);
+        await appendContentInputvalue(browser, fieldSelector, fieldValue);
+        info(
+          "form edited, waiting for test notification of PasswordEditedOrGenerated"
+        );
+        await passwordEditedMessage;
+        info(
+          "Resolved listenForTestNotification promise, waiting for doorhanger"
+        );
+        await passwordChangeDoorhangerPromise;
+        // wait for possible confirmation hint
+        try {
+          info("Waiting for hintDidShow");
+          await TestUtils.waitForCondition(
+            () => hintDidShow,
+            `Waiting for confirmationHint popup`,
+            undefined,
+            25
+          );
+        } catch (ex) {
+          info("Got expected timeout from the waitForCondition: " + ex);
+        } finally {
+          info("confirmationHint check done, assert on hintDidShow");
+          Assert.equal(
+            hintDidShow,
+            expectedConfirmation,
+            "Confirmation hint shown"
+          );
+        }
+        info(
+          "Waiting for loginModifiedPromise, expectedConfirmation? " +
+            expectedConfirmation
+        );
+        await loginModifiedPromise;
+
+        // the previous doorhanger would have old values, verify it was updated/replaced with new values from the form
+        info("Verifying the doorhanger");
+        notif = await openAndVerifyDoorhanger(browser, "password-change", {
+          dismissed: true,
+          anchorExtraAttr: expectedConfirmation ? "attention" : "",
+          usernameValue: expectedDoorhangerUsername,
+          passwordLength: expectedDoorhangerPassword.length,
+        });
+        await cleanupDoorhanger(notif);
+      }
+
+      // submit the form to verify we still get the right doorhanger values
+      let passwordChangeDoorhangerPromise = waitForDoorhanger(
+        browser,
+        "password-change"
+      );
+      await submitForm(browser);
+      info("form submitted, waiting for doorhanger");
+      await passwordChangeDoorhangerPromise;
+      notif = await openAndVerifyDoorhanger(browser, "password-change", {
+        dismissed: false,
+        anchorExtraAttr: "",
+        usernameValue: "someuser",
+        passwordLength: LoginTestUtils.generation.LENGTH + 2,
+      });
+      await cleanupDoorhanger(notif);
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_httpsUpgrade.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_httpsUpgrade.js
new file mode 100644
index 0000000000..0f4ca8491f
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_httpsUpgrade.js
@@ -0,0 +1,310 @@
+/*
+ * Test capture popup notifications with HTTPS upgrades
+ */
+
+let nsLoginInfo = new Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  Ci.nsILoginInfo,
+  "init"
+);
+let login1 = new nsLoginInfo(
+  "http://example.com",
+  "http://example.com",
+  null,
+  "notifyu1",
+  "notifyp1",
+  "user",
+  "pass"
+);
+let login1HTTPS = new nsLoginInfo(
+  "https://example.com",
+  "https://example.com",
+  null,
+  "notifyu1",
+  "notifyp1",
+  "user",
+  "pass"
+);
+
+add_task(async function test_httpsUpgradeCaptureFields_noChange() {
+  info(
+    "Check that we don't prompt to remember when capturing an upgraded login with no change"
+  );
+  await Services.logins.addLoginAsync(login1);
+  // Sanity check the HTTP login exists.
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should have the HTTP login");
+
+  await testSubmittingLoginForm(
+    "subtst_notifications_1.html",
+    function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger("password-save");
+      Assert.ok(!notif, "checking for no notification popup");
+    },
+    "https://example.com"
+  ); // This is HTTPS whereas the saved login is HTTP
+
+  logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login still");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(
+    login.origin,
+    "http://example.com",
+    "Check the origin is unchanged"
+  );
+  Assert.equal(login.username, "notifyu1", "Check the username is unchanged");
+  Assert.equal(login.password, "notifyp1", "Check the password is unchanged");
+  Assert.equal(login.timesUsed, 2, "Check times used increased");
+
+  Services.logins.removeLogin(login1);
+});
+
+add_task(async function test_httpsUpgradeCaptureFields_changePW() {
+  info(
+    "Check that we prompt to change when capturing an upgraded login with a new PW"
+  );
+  await Services.logins.addLoginAsync(login1);
+  // Sanity check the HTTP login exists.
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should have the HTTP login");
+
+  await testSubmittingLoginForm(
+    "subtst_notifications_8.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "pass2",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "checking for a change popup");
+
+      await checkDoorhangerUsernamePassword("notifyu1", "pass2");
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+
+      Assert.ok(
+        !getCaptureDoorhanger("password-change"),
+        "popup should be gone"
+      );
+    },
+    "https://example.com"
+  ); // This is HTTPS whereas the saved login is HTTP
+
+  await checkOnlyLoginWasUsedTwice({ justChanged: true });
+  logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login still");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(
+    login.origin,
+    "https://example.com",
+    "Check the origin is upgraded"
+  );
+  Assert.equal(
+    login.formActionOrigin,
+    "https://example.com",
+    "Check the formActionOrigin is upgraded"
+  );
+  Assert.equal(login.username, "notifyu1", "Check the username is unchanged");
+  Assert.equal(login.password, "pass2", "Check the password changed");
+  Assert.equal(login.timesUsed, 2, "Check times used increased");
+
+  Services.logins.removeAllUserFacingLogins();
+});
+
+add_task(
+  async function test_httpsUpgradeCaptureFields_changePWWithBothSchemesSaved() {
+    info(
+      "Check that we prompt to change and properly save when capturing an upgraded login with a new PW when an http login also exists for that username"
+    );
+    await Services.logins.addLogins([login1, login1HTTPS]);
+
+    let logins = await Services.logins.getAllLogins();
+    Assert.equal(logins.length, 2, "Should have both HTTP and HTTPS logins");
+
+    await testSubmittingLoginForm(
+      "subtst_notifications_8.html",
+      async function (fieldValues) {
+        Assert.equal(
+          fieldValues.username,
+          "notifyu1",
+          "Checking submitted username"
+        );
+        Assert.equal(
+          fieldValues.password,
+          "pass2",
+          "Checking submitted password"
+        );
+        let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+        Assert.ok(notif, "checking for a change popup");
+
+        await checkDoorhangerUsernamePassword("notifyu1", "pass2");
+        clickDoorhangerButton(notif, CHANGE_BUTTON);
+
+        Assert.ok(
+          !getCaptureDoorhanger("password-change"),
+          "popup should be gone"
+        );
+      },
+      "https://example.com"
+    );
+
+    logins = await Services.logins.getAllLogins();
+    Assert.equal(logins.length, 2, "Should have 2 logins still");
+    let loginHTTP = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+    let loginHTTPS = logins[1].QueryInterface(Ci.nsILoginMetaInfo);
+    Assert.ok(
+      LoginHelper.doLoginsMatch(login1, loginHTTP, { ignorePassword: true }),
+      "Check HTTP login is equal"
+    );
+    Assert.equal(loginHTTP.timesUsed, 1, "Check times used stayed the same");
+    Assert.equal(
+      loginHTTP.timeCreated,
+      loginHTTP.timePasswordChanged,
+      "login.timeCreated == login.timePasswordChanged"
+    );
+    Assert.equal(
+      loginHTTP.timeLastUsed,
+      loginHTTP.timePasswordChanged,
+      "timeLastUsed == timePasswordChanged"
+    );
+
+    Assert.ok(
+      LoginHelper.doLoginsMatch(login1HTTPS, loginHTTPS, {
+        ignorePassword: true,
+      }),
+      "Check HTTPS login is equal"
+    );
+    Assert.equal(
+      loginHTTPS.username,
+      "notifyu1",
+      "Check the username is unchanged"
+    );
+    Assert.equal(loginHTTPS.password, "pass2", "Check the password changed");
+    Assert.equal(loginHTTPS.timesUsed, 2, "Check times used increased");
+    Assert.ok(
+      loginHTTPS.timeCreated < loginHTTPS.timePasswordChanged,
+      "login.timeCreated < login.timePasswordChanged"
+    );
+    Assert.equal(
+      loginHTTPS.timeLastUsed,
+      loginHTTPS.timePasswordChanged,
+      "timeLastUsed == timePasswordChanged"
+    );
+
+    Services.logins.removeAllUserFacingLogins();
+  }
+);
+
+add_task(async function test_httpsUpgradeCaptureFields_captureMatchingHTTP() {
+  info("Capture a new HTTP login which matches a stored HTTPS one.");
+  await Services.logins.addLoginAsync(login1HTTPS);
+
+  const storageChangedPromise = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    (_, data) => data == "addLogin"
+  );
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(notif, "got notification popup");
+
+      Assert.equal(
+        (await Services.logins.getAllLogins()).length,
+        1,
+        "Should only have the HTTPS login"
+      );
+
+      await checkDoorhangerUsernamePassword("notifyu1", "notifyp1");
+      clickDoorhangerButton(notif, REMEMBER_BUTTON);
+    }
+  );
+
+  await storageChangedPromise;
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 2, "Should have both HTTP and HTTPS logins");
+  for (let login of logins) {
+    login = login.QueryInterface(Ci.nsILoginMetaInfo);
+    Assert.equal(
+      login.username,
+      "notifyu1",
+      "Check the username used on the new entry"
+    );
+    Assert.equal(
+      login.password,
+      "notifyp1",
+      "Check the password used on the new entry"
+    );
+    Assert.equal(login.timesUsed, 1, "Check times used on entry");
+  }
+
+  info(
+    "Make sure Remember took effect and we don't prompt for an existing HTTP login"
+  );
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger("password-save");
+      Assert.ok(!notif, "checking for no notification popup");
+    }
+  );
+
+  logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 2, "Should have both HTTP and HTTPS still");
+
+  let httpsLogins = LoginHelper.searchLoginsWithObject({
+    origin: "https://example.com",
+  });
+  Assert.equal(httpsLogins.length, 1, "Check https logins count");
+  let httpsLogin = httpsLogins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.ok(httpsLogin.equals(login1HTTPS), "Check HTTPS login didn't change");
+  Assert.equal(httpsLogin.timesUsed, 1, "Check times used");
+
+  let httpLogins = LoginHelper.searchLoginsWithObject({
+    origin: "http://example.com",
+  });
+  Assert.equal(httpLogins.length, 1, "Check http logins count");
+  let httpLogin = httpLogins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.ok(httpLogin.equals(login1), "Check HTTP login is as expected");
+  Assert.equal(httpLogin.timesUsed, 2, "Check times used increased");
+
+  Services.logins.removeLogin(login1);
+  Services.logins.removeLogin(login1HTTPS);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_multipage_form.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_multipage_form.js
new file mode 100644
index 0000000000..7aace425b9
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_multipage_form.js
@@ -0,0 +1,182 @@
+/**
+ * Test that the doorhanger notification for password saving is populated with
+ * the correct values in various password capture cases (multipage login form).
+ */
+
+const testCases = [
+  {
+    name: "No saved logins, username and password",
+    username: "username",
+    password: "password",
+    expectOutcome: [
+      {
+        username: "username",
+        password: "password",
+      },
+    ],
+  },
+  {
+    name: "No saved logins, password with empty username",
+    username: "",
+    password: "password",
+    expectOutcome: [
+      {
+        username: "",
+        password: "password",
+      },
+    ],
+  },
+  {
+    name: "Saved login with username, update password",
+    username: "username",
+    oldPassword: "password",
+    password: "newPassword",
+    expectOutcome: [
+      {
+        username: "username",
+        password: "newPassword",
+      },
+    ],
+  },
+  {
+    name: "Saved login with username, add username",
+    oldUsername: "username",
+    username: "newUsername",
+    password: "password",
+    expectOutcome: [
+      {
+        username: "newUsername",
+        password: "password",
+      },
+    ],
+  },
+  {
+    name: "Saved login with no username, add username and different password",
+    oldUsername: "",
+    username: "username",
+    oldPassword: "password",
+    password: "newPassword",
+    expectOutcome: [
+      {
+        username: "",
+        password: "password",
+      },
+      {
+        username: "username",
+        password: "newPassword",
+      },
+    ],
+  },
+];
+
+add_task(async function test_initialize() {
+  Services.prefs.setBoolPref("signon.usernameOnlyForm.enabled", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.usernameOnlyForm.enabled");
+  });
+});
+
+for (let testData of testCases) {
+  let tmp = {
+    async [testData.name]() {
+      info("testing with: " + JSON.stringify(testData));
+      await test_save_change(testData);
+    },
+  };
+  add_task(tmp[testData.name]);
+}
+
+async function test_save_change(testData) {
+  let { oldUsername, username, oldPassword, password, expectOutcome } =
+    testData;
+  // Add a login for the origin of the form if testing a change notification.
+  if (oldPassword) {
+    await Services.logins.addLoginAsync(
+      LoginTestUtils.testData.formLogin({
+        origin: "https://example.com",
+        formActionOrigin: "https://example.com",
+        username: typeof oldUsername !== "undefined" ? oldUsername : username,
+        password: oldPassword,
+      })
+    );
+  }
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url:
+        "https://example.com/browser/toolkit/components/" +
+        "passwordmgr/test/browser/form_multipage.html",
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+      // Update the username filed from the test case.
+      info(`update form with username: ${username}`);
+      await changeContentFormValues(browser, {
+        "#form-basic-username": username,
+      });
+
+      // Submit the username-only form, which then advance to the password-only
+      // form.
+      info(`submit the username-only form`);
+      await SpecialPowers.spawn(browser, [], async function () {
+        let doc = this.content.document;
+        doc.getElementById("form-basic-submit").click();
+        await ContentTaskUtils.waitForCondition(() => {
+          return doc.getElementById("form-basic-password");
+        }, "Wait for the username field");
+      });
+
+      // Update the password filed from the test case.
+      info(`update form with password: ${password}`);
+      await changeContentFormValues(browser, {
+        "#form-basic-password": password,
+      });
+
+      // Submit the form.
+      info(`submit the password-only form`);
+      let formSubmittedPromise = listenForTestNotification("ShowDoorhanger");
+      await SpecialPowers.spawn(browser, [], async function () {
+        let doc = this.content.document;
+        doc.getElementById("form-basic-submit").click();
+      });
+      await formSubmittedPromise;
+
+      // Simulate the action on the notification to request the login to be
+      // saved, and wait for the data to be updated or saved based on the type
+      // of operation we expect.
+      let expectedNotification, expectedDoorhanger;
+      if (oldPassword !== undefined && oldUsername !== undefined) {
+        expectedNotification = "addLogin";
+        expectedDoorhanger = "password-save";
+      } else if (oldPassword !== undefined) {
+        expectedNotification = "modifyLogin";
+        expectedDoorhanger = "password-change";
+      } else {
+        expectedNotification = "addLogin";
+        expectedDoorhanger = "password-save";
+      }
+
+      info("Waiting for doorhanger of type: " + expectedDoorhanger);
+      let notif = await waitForDoorhanger(browser, expectedDoorhanger);
+
+      // Check the actual content of the popup notification.
+      await checkDoorhangerUsernamePassword(username, password);
+
+      let promiseLogin = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == expectedNotification
+      );
+      await clickDoorhangerButton(notif, REMEMBER_BUTTON);
+      await promiseLogin;
+      await cleanupDoorhanger(notif); // clean slate for the next test
+
+      // Check that the values in the database match the expected values.
+      await verifyLogins(expectOutcome);
+    }
+  );
+
+  // Clean up the database before the next test case is executed.
+  Services.logins.removeAllUserFacingLogins();
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_password_edits.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_password_edits.js
new file mode 100644
index 0000000000..414208eaa5
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_password_edits.js
@@ -0,0 +1,220 @@
+/**
+ * Test changing the password inside the doorhanger notification for passwords.
+ *
+ * We check the following cases:
+ *   - Editing the password of a new login.
+ *   - Editing the password of an existing login.
+ *   - Changing both username and password to an existing login.
+ *   - Changing the username to an existing login.
+ *   - Editing username to an empty one and a new password.
+ *
+ * If both the username and password matches an already existing login, we should not
+ * update it's password, but only it's usage timestamp and count.
+ */
+add_task(async function test_edit_password() {
+  let testCases = [
+    {
+      description: "No saved logins, update password in doorhanger",
+      usernameInPage: "username",
+      passwordInPage: "password",
+      passwordChangedTo: "newPassword",
+      timesUsed: 1,
+    },
+    {
+      description: "Login is saved, update password in doorhanger",
+      usernameInPage: "username",
+      usernameInPageExists: true,
+      passwordInPage: "password",
+      passwordInStorage: "oldPassword",
+      passwordChangedTo: "newPassword",
+      timesUsed: 2,
+    },
+    {
+      description:
+        "Change username in doorhanger to match saved login, update password in doorhanger",
+      usernameInPage: "username",
+      usernameChangedTo: "newUsername",
+      usernameChangedToExists: true,
+      passwordInPage: "password",
+      passwordChangedTo: "newPassword",
+      timesUsed: 2,
+    },
+    {
+      description:
+        "Change username in doorhanger to match saved login, dont update password in doorhanger",
+      usernameInPage: "username",
+      usernameChangedTo: "newUsername",
+      usernameChangedToExists: true,
+      passwordInPage: "password",
+      passwordChangedTo: "password",
+      timesUsed: 2,
+      checkPasswordNotUpdated: true,
+    },
+    {
+      description:
+        "Change username and password in doorhanger to match saved empty-username login",
+      usernameInPage: "newUsername",
+      usernameChangedTo: "",
+      usernameChangedToExists: true,
+      passwordInPage: "password",
+      passwordChangedTo: "newPassword",
+      timesUsed: 2,
+    },
+  ];
+
+  for (let testCase of testCases) {
+    info("Test case: " + JSON.stringify(testCase));
+    // Clean state before the test case is executed.
+    await LoginTestUtils.clearData();
+    await cleanupDoorhanger();
+    await cleanupPasswordNotifications();
+
+    // Create the pre-existing logins when needed.
+    if (testCase.usernameInPageExists) {
+      await Services.logins.addLoginAsync(
+        LoginTestUtils.testData.formLogin({
+          origin: "https://example.com",
+          formActionOrigin: "https://example.com",
+          username: testCase.usernameInPage,
+          password: testCase.passwordInStorage,
+        })
+      );
+    }
+
+    if (testCase.usernameChangedToExists) {
+      await Services.logins.addLoginAsync(
+        LoginTestUtils.testData.formLogin({
+          origin: "https://example.com",
+          formActionOrigin: "https://example.com",
+          username: testCase.usernameChangedTo,
+          password: testCase.passwordChangedTo,
+        })
+      );
+    }
+
+    let formFilledPromise = listenForTestNotification("FormProcessed");
+
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url:
+          "https://example.com/browser/toolkit/components/" +
+          "passwordmgr/test/browser/form_basic.html",
+      },
+      async function (browser) {
+        await formFilledPromise;
+
+        // Set the form to a known state so we can expect a single PasswordEditedOrGenerated message
+        await initForm(browser, {
+          "#form-basic-username": testCase.usernameInPage,
+          "#form-basic-password": "",
+        });
+
+        let passwordEditedPromise = listenForTestNotification(
+          "PasswordEditedOrGenerated"
+        );
+        info("Editing the form");
+        await changeContentFormValues(browser, {
+          "#form-basic-password": testCase.passwordInPage,
+        });
+        info("Waiting for passwordEditedPromise");
+        await passwordEditedPromise;
+
+        // reset doorhanger/notifications, we're only interested in the submit outcome
+        await cleanupDoorhanger();
+        await cleanupPasswordNotifications();
+        // reset message cache, we're only interested in the submit outcome
+        await clearMessageCache(browser);
+
+        // Submit the form in the content page with the credentials from the test
+        // case. This will cause the doorhanger notification to be displayed.
+        info("Submitting the form");
+        let formSubmittedPromise = listenForTestNotification("ShowDoorhanger");
+        let promiseShown = BrowserTestUtils.waitForEvent(
+          PopupNotifications.panel,
+          "popupshown",
+          event => event.target == PopupNotifications.panel
+        );
+        await SpecialPowers.spawn(browser, [], function () {
+          content.document.getElementById("form-basic").submit();
+        });
+        await formSubmittedPromise;
+
+        let notif = await waitForDoorhanger(browser, "any");
+        Assert.ok(!notif.dismissed, "Doorhanger is not dismissed");
+        await promiseShown;
+
+        // Modify the username & password in the dialog if requested.
+        await updateDoorhangerInputValues({
+          username: testCase.usernameChangedTo,
+          password: testCase.passwordChangedTo,
+        });
+
+        // We expect a modifyLogin notification if the final username used by the
+        // dialog exists in the logins database, otherwise an addLogin one.
+        let expectModifyLogin =
+          typeof testCase.usernameChangedTo !== "undefined"
+            ? testCase.usernameChangedToExists
+            : testCase.usernameInPageExists;
+
+        // Simulate the action on the notification to request the login to be
+        // saved, and wait for the data to be updated or saved based on the type
+        // of operation we expect.
+        let expectedNotification = expectModifyLogin
+          ? "modifyLogin"
+          : "addLogin";
+        let promiseLogin = TestUtils.topicObserved(
+          "passwordmgr-storage-changed",
+          (_, data) => data == expectedNotification
+        );
+
+        let promiseHidden = BrowserTestUtils.waitForEvent(
+          PopupNotifications.panel,
+          "popuphidden"
+        );
+        clickDoorhangerButton(notif, CHANGE_BUTTON);
+        await promiseHidden;
+        info("Waiting for storage changed");
+        let [result] = await promiseLogin;
+
+        // Check that the values in the database match the expected values.
+        let login = expectModifyLogin
+          ? result
+              .QueryInterface(Ci.nsIArray)
+              .queryElementAt(1, Ci.nsILoginInfo)
+          : result.QueryInterface(Ci.nsILoginInfo);
+        let meta = login.QueryInterface(Ci.nsILoginMetaInfo);
+
+        let expectedLogin = {
+          username:
+            "usernameChangedTo" in testCase
+              ? testCase.usernameChangedTo
+              : testCase.usernameInPage,
+          password:
+            "passwordChangedTo" in testCase
+              ? testCase.passwordChangedTo
+              : testCase.passwordInPage,
+          timesUsed: testCase.timesUsed,
+        };
+        // Check that the password was not updated if the user is empty
+        if (testCase.checkPasswordNotUpdated) {
+          expectedLogin.usedSince = meta.timeCreated;
+          expectedLogin.timeCreated = meta.timePasswordChanged;
+        }
+        await verifyLogins([expectedLogin]);
+      }
+    );
+  }
+});
+
+async function initForm(browser, formDefaults = {}) {
+  await ContentTask.spawn(
+    browser,
+    formDefaults,
+    async function (selectorValues) {
+      for (let [sel, value] of Object.entries(selectorValues)) {
+        content.document.querySelector(sel).value = value;
+      }
+    }
+  );
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_promptToChangePassword.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_promptToChangePassword.js
new file mode 100644
index 0000000000..0911378d66
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_promptToChangePassword.js
@@ -0,0 +1,685 @@
+/**
+ * Test result of different input to the promptToChangePassword doorhanger
+ */
+
+"use strict";
+
+// The origin for the test URIs.
+const TEST_ORIGIN = "https://example.com";
+const passwordInputSelector = "#form-basic-password";
+const usernameInputSelector = "#form-basic-username";
+
+const availLoginsByValue = new Map();
+let savedLoginsByName;
+const finalLoginsByGuid = new Map();
+let finalLogins;
+
+const availLogins = {
+  emptyXYZ: LoginTestUtils.testData.formLogin({
+    username: "",
+    password: "xyz",
+  }),
+  bobXYZ: LoginTestUtils.testData.formLogin({
+    username: "bob",
+    password: "xyz",
+  }),
+  bobABC: LoginTestUtils.testData.formLogin({
+    username: "bob",
+    password: "abc",
+  }),
+};
+availLoginsByValue.set(availLogins.emptyXYZ, "emptyXYZ");
+availLoginsByValue.set(availLogins.bobXYZ, "bobXYZ");
+availLoginsByValue.set(availLogins.bobABC, "bobABC");
+
+async function showChangePasswordDoorhanger(
+  browser,
+  oldLogin,
+  formLogin,
+  { notificationType = "password-change", autoSavedLoginGuid = "" } = {}
+) {
+  let windowGlobal = browser.browsingContext.currentWindowGlobal;
+  let loginManagerActor = windowGlobal.getActor("LoginManager");
+  let prompter = loginManagerActor._getPrompter(browser, null);
+  Assert.ok(
+    !PopupNotifications.isPanelOpen,
+    "Check the doorhanger isn't already open"
+  );
+
+  let promiseShown = BrowserTestUtils.waitForEvent(
+    PopupNotifications.panel,
+    "popupshown"
+  );
+
+  prompter.promptToChangePassword(
+    browser,
+    oldLogin,
+    formLogin,
+    false, // dimissed prompt
+    false, // notifySaved
+    autoSavedLoginGuid
+  );
+  await promiseShown;
+
+  let notif = getCaptureDoorhanger(notificationType);
+  Assert.ok(notif, `${notificationType} notification exists`);
+
+  let { panel } = PopupNotifications;
+  let notificationElement = panel.childNodes[0];
+  await BrowserTestUtils.waitForCondition(() => {
+    return (
+      notificationElement.querySelector("#password-notification-password")
+        .value == formLogin.password &&
+      notificationElement.querySelector("#password-notification-username")
+        .value == formLogin.username
+    );
+  }, "Wait for the notification panel to be populated");
+  return notif;
+}
+
+async function setupLogins(...logins) {
+  Services.logins.removeAllUserFacingLogins();
+  let savedLogins = {};
+  let timesCreated = new Set();
+  for (let login of logins) {
+    let loginName = availLoginsByValue.get(login);
+    let savedLogin = await LoginTestUtils.addLogin(login);
+    // we rely on sorting by timeCreated so ensure none are identical
+    Assert.ok(
+      !timesCreated.has(savedLogin.timeCreated),
+      "Each login has a different timeCreated"
+    );
+    timesCreated.add(savedLogin.timeCreated);
+    savedLogins[loginName || savedLogin.guid] = savedLogin.clone();
+  }
+  return savedLogins;
+}
+
+add_setup(async function () {
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.autofillForms", false]],
+  });
+  Assert.ok(!PopupNotifications.isPanelOpen, "No notifications panel open");
+});
+
+async function promptToChangePasswordTest(testData) {
+  info("Starting: " + testData.name);
+  savedLoginsByName = await setupLogins(...testData.initialSavedLogins);
+  await SimpleTest.promiseFocus();
+  info("got focus");
+
+  let oldLogin = savedLoginsByName[testData.promptArgs.oldLogin];
+  let changeLogin = LoginTestUtils.testData.formLogin(
+    testData.promptArgs.changeLogin
+  );
+  let options;
+  if (testData.autoSavedLoginName) {
+    options = {
+      autoSavedLoginGuid: savedLoginsByName[testData.autoSavedLoginName].guid,
+    };
+  }
+  info(
+    "Waiting for showChangePasswordDoorhanger, username: " +
+      changeLogin.username
+  );
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      TEST_ORIGIN,
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      let notif = await showChangePasswordDoorhanger(
+        browser,
+        oldLogin,
+        changeLogin,
+        options
+      );
+
+      await updateDoorhangerInputValues(testData.promptTextboxValues);
+
+      let mainActionButton = getDoorhangerButton(notif, CHANGE_BUTTON);
+      Assert.equal(
+        mainActionButton.label,
+        testData.expectedButtonLabel,
+        "Check button label"
+      );
+
+      let { panel } = PopupNotifications;
+      let promiseHidden = BrowserTestUtils.waitForEvent(panel, "popuphidden");
+      let storagePromise;
+      if (testData.expectedStorageChange) {
+        storagePromise = TestUtils.topicObserved("passwordmgr-storage-changed");
+      }
+
+      info("Clicking mainActionButton");
+      mainActionButton.doCommand();
+      info("Waiting for promiseHidden");
+      await promiseHidden;
+      info("Waiting for storagePromise");
+      await storagePromise;
+
+      // ensure the notification was removed to keep clean state for next run
+      await cleanupDoorhanger(notif);
+
+      info(testData.resultDescription);
+
+      finalLoginsByGuid.clear();
+      finalLogins = await Services.logins.getAllLogins();
+      finalLogins.sort((a, b) => a.timeCreated > b.timeCreated);
+
+      for (let l of finalLogins) {
+        info(`saved login: ${l.guid}: ${l.username}/${l.password}`);
+        finalLoginsByGuid.set(l.guid, l);
+      }
+      info("verifyLogins next");
+      await verifyLogins(testData.expectedResultLogins);
+      if (testData.resultCheck) {
+        testData.resultCheck();
+      }
+    }
+  );
+}
+
+let tests = [
+  {
+    name: "Add username to sole login",
+    initialSavedLogins: [availLogins.emptyXYZ],
+    promptArgs: {
+      oldLogin: "emptyXYZ",
+      changeLogin: {
+        username: "zaphod",
+        password: "xyz",
+      },
+    },
+    promptTextboxValues: {},
+    expectedButtonLabel: "Update",
+    resultDescription: "The existing login just gets a new password",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "zaphod",
+        password: "xyz",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.emptyXYZ.guid,
+        "Check guid"
+      );
+    },
+  },
+  {
+    name: "Change password of the sole login",
+    initialSavedLogins: [availLogins.bobXYZ],
+    promptArgs: {
+      oldLogin: "bobXYZ",
+      changeLogin: {
+        username: "bob",
+        password: "&*$",
+      },
+    },
+    promptTextboxValues: {},
+    expectedButtonLabel: "Update",
+    resultDescription: "The existing login just gets a new password",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "bob",
+        password: "&*$",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.bobXYZ.guid,
+        "Check guid"
+      );
+    },
+  },
+  {
+    name: "Change password of the sole empty-username login",
+    initialSavedLogins: [availLogins.emptyXYZ],
+    promptArgs: {
+      oldLogin: "emptyXYZ",
+      changeLogin: {
+        username: "",
+        password: "&*$",
+      },
+    },
+    promptTextboxValues: {},
+    expectedButtonLabel: "Update",
+    resultDescription: "The existing login just gets a new password",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "",
+        password: "&*$",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.emptyXYZ.guid,
+        "Check guid"
+      );
+    },
+  },
+  {
+    name: "Add different username to empty-usernamed login",
+    initialSavedLogins: [availLogins.emptyXYZ, availLogins.bobABC],
+    promptArgs: {
+      oldLogin: "emptyXYZ",
+      changeLogin: {
+        username: "alice",
+        password: "xyz",
+      },
+    },
+    promptTextboxValues: {},
+    expectedButtonLabel: "Update",
+    resultDescription: "The existing login just gets a new username",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "alice",
+        password: "xyz",
+      },
+      {
+        username: "bob",
+        password: "abc",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.emptyXYZ.guid,
+        "Check guid"
+      );
+      Assert.ok(
+        finalLogins[0].timeLastUsed > savedLoginsByName.emptyXYZ.timeLastUsed,
+        "Check timeLastUsed of 0th login"
+      );
+    },
+  },
+  {
+    name: "Add username to autosaved login to match an existing usernamed login",
+    initialSavedLogins: [availLogins.emptyXYZ, availLogins.bobABC],
+    autoSavedLoginName: "emptyXYZ",
+    promptArgs: {
+      oldLogin: "emptyXYZ",
+      changeLogin: {
+        username: "bob",
+        password: availLogins.emptyXYZ.password,
+      },
+    },
+    promptTextboxValues: {},
+    expectedButtonLabel: "Update",
+    resultDescription:
+      "Empty-username login is removed, other login gets the empty-login's password",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "bob",
+        password: "xyz",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.bobABC.guid,
+        "Check guid"
+      );
+      Assert.ok(
+        finalLogins[0].timeLastUsed > savedLoginsByName.bobABC.timeLastUsed,
+        "Check timeLastUsed changed"
+      );
+    },
+  },
+  {
+    name: "Add username to non-autosaved login to match an existing usernamed login",
+    initialSavedLogins: [availLogins.emptyXYZ, availLogins.bobABC],
+    autoSavedLoginName: "",
+    promptArgs: {
+      oldLogin: "emptyXYZ",
+      changeLogin: {
+        username: "bob",
+        password: availLogins.emptyXYZ.password,
+      },
+    },
+    promptTextboxValues: {},
+    expectedButtonLabel: "Update",
+    // We can't end up with duplicates (bob:xyz and bob:ABC) so the following seems reasonable.
+    // We could delete the emptyXYZ but we would want to intelligently merge metadata.
+    resultDescription:
+      "Multiple login matches but user indicated they want bob:xyz in the prompt so modify bob to give that",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "",
+        password: "xyz",
+      },
+      {
+        username: "bob",
+        password: "xyz",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.emptyXYZ.guid,
+        "Check guid"
+      );
+      Assert.equal(
+        finalLogins[0].timeLastUsed,
+        savedLoginsByName.emptyXYZ.timeLastUsed,
+        "Check timeLastUsed didn't change"
+      );
+      Assert.equal(
+        finalLogins[0].timePasswordChanged,
+        savedLoginsByName.emptyXYZ.timePasswordChanged,
+        "Check timePasswordChanged didn't change"
+      );
+
+      Assert.equal(
+        finalLogins[1].guid,
+        savedLoginsByName.bobABC.guid,
+        "Check guid"
+      );
+      Assert.ok(
+        finalLogins[1].timeLastUsed > savedLoginsByName.bobABC.timeLastUsed,
+        "Check timeLastUsed did change"
+      );
+      Assert.ok(
+        finalLogins[1].timePasswordChanged >
+          savedLoginsByName.bobABC.timePasswordChanged,
+        "Check timePasswordChanged did change"
+      );
+    },
+  },
+  {
+    name: "Username & password changes to an auto-saved login apply to matching usernamed-login",
+    // when we update an auto-saved login - changing both username & password, is
+    // the matching login updated and empty-username login removed?
+    initialSavedLogins: [availLogins.emptyXYZ, availLogins.bobABC],
+    autoSavedLoginName: "emptyXYZ",
+    promptArgs: {
+      oldLogin: "emptyXYZ",
+      changeLogin: {
+        username: "bob",
+        password: "xyz",
+      },
+    },
+    promptTextboxValues: {
+      // type a new password in the doorhanger
+      password: "newpassword",
+    },
+    expectedButtonLabel: "Update",
+    resultDescription:
+      "The empty-username login is removed, other login gets the new password",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "bob",
+        password: "newpassword",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.bobABC.guid,
+        "Check guid"
+      );
+      Assert.ok(
+        finalLogins[0].timeLastUsed > savedLoginsByName.bobABC.timeLastUsed,
+        "Check timeLastUsed did change"
+      );
+    },
+  },
+  {
+    name: "Username & password changes to a non-auto-saved login matching usernamed-login",
+    // when we update a non-auto-saved login - changing both username & password, is
+    // the matching login updated and empty-username login unchanged?
+    initialSavedLogins: [availLogins.emptyXYZ, availLogins.bobABC],
+    autoSavedLoginName: "", // no auto-saved logins for this session
+    promptArgs: {
+      oldLogin: "emptyXYZ",
+      changeLogin: {
+        username: "bob",
+        password: "xyz",
+      },
+    },
+    promptTextboxValues: {
+      // type a new password in the doorhanger
+      password: "newpassword",
+    },
+    expectedButtonLabel: "Update",
+    resultDescription:
+      "The empty-username login is not changed, other login gets the new password",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "",
+        password: "xyz",
+      },
+      {
+        username: "bob",
+        password: "newpassword",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.emptyXYZ.guid,
+        "Check guid"
+      );
+      Assert.equal(
+        finalLogins[0].timeLastUsed,
+        savedLoginsByName.emptyXYZ.timeLastUsed,
+        "Check timeLastUsed didn't change"
+      );
+      Assert.equal(
+        finalLogins[0].timePasswordChanged,
+        savedLoginsByName.emptyXYZ.timePasswordChanged,
+        "Check timePasswordChanged didn't change"
+      );
+      Assert.equal(
+        finalLogins[1].guid,
+        savedLoginsByName.bobABC.guid,
+        "Check guid"
+      );
+      Assert.ok(
+        finalLogins[1].timeLastUsed > savedLoginsByName.bobABC.timeLastUsed,
+        "Check timeLastUsed did change"
+      );
+      Assert.ok(
+        finalLogins[1].timePasswordChanged >
+          savedLoginsByName.bobABC.timePasswordChanged,
+        "Check timePasswordChanged did change"
+      );
+    },
+  },
+  {
+    name: "Remove the username and change password of autosaved login",
+    initialSavedLogins: [availLogins.bobABC],
+    autoSavedLoginName: "bobABC",
+    promptArgs: {
+      oldLogin: "bobABC",
+      changeLogin: {
+        username: "bob",
+        password: "abc!", // trigger change prompt with a password change
+      },
+    },
+    promptTextboxValues: {
+      username: "",
+    },
+    expectedButtonLabel: "Update",
+    resultDescription:
+      "The auto-saved login is updated with new empty-username login and new password",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "",
+        password: "abc!",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.bobABC.guid,
+        "Check guid"
+      );
+      Assert.ok(
+        finalLogins[0].timeLastUsed > savedLoginsByName.bobABC.timeLastUsed,
+        "Check timeLastUsed did change"
+      );
+      Assert.ok(
+        finalLogins[0].timePasswordChanged >
+          savedLoginsByName.bobABC.timePasswordChanged,
+        "Check timePasswordChanged did change"
+      );
+    },
+  },
+  {
+    name: "Remove the username and change password of non-autosaved login",
+    initialSavedLogins: [availLogins.bobABC],
+    // no autosaved guid
+    promptArgs: {
+      oldLogin: "bobABC",
+      changeLogin: {
+        username: "bob",
+        password: "abc!", // trigger change prompt with a password change
+      },
+    },
+    promptTextboxValues: {
+      username: "",
+    },
+    expectedButtonLabel: "Save",
+    resultDescription:
+      "A new empty-username login is created with the new password",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "bob",
+        password: "abc",
+      },
+      {
+        username: "",
+        password: "abc!",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.bobABC.guid,
+        "Check guid"
+      );
+      Assert.equal(
+        finalLogins[0].timeLastUsed,
+        savedLoginsByName.bobABC.timeLastUsed,
+        "Check timeLastUsed didn't change"
+      );
+      Assert.equal(
+        finalLogins[0].timePasswordChanged,
+        savedLoginsByName.bobABC.timePasswordChanged,
+        "Check timePasswordChanged didn't change"
+      );
+    },
+  },
+  {
+    name: "Remove username from the auto-saved sole login",
+    initialSavedLogins: [availLogins.bobABC],
+    autoSavedLoginName: "bobABC",
+    promptArgs: {
+      oldLogin: "bobABC",
+      changeLogin: {
+        username: "bob",
+        password: "abc!", // trigger change prompt with a password change
+      },
+    },
+    promptTextboxValues: {
+      username: "",
+      password: "abc", // put password back to what it was
+    },
+    expectedButtonLabel: "Update",
+    resultDescription: "The existing login is updated",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "",
+        password: "abc",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.bobABC.guid,
+        "Check guid"
+      );
+      Assert.ok(
+        finalLogins[0].timeLastUsed > savedLoginsByName.bobABC.timeLastUsed,
+        "Check timeLastUsed did change"
+      );
+      todo_is(
+        finalLogins[0].timePasswordChanged,
+        savedLoginsByName.bobABC.timePasswordChanged,
+        "Check timePasswordChanged didn't change"
+      );
+    },
+  },
+  {
+    name: "Remove username from the non-auto-saved sole login",
+    initialSavedLogins: [availLogins.bobABC],
+    // no autoSavedLoginGuid
+    promptArgs: {
+      oldLogin: "bobABC",
+      changeLogin: {
+        username: "bob",
+        password: "abc!", // trigger change prompt with a password change
+      },
+    },
+    promptTextboxValues: {
+      username: "",
+      password: "abc", // put password back to what it was
+    },
+    expectedButtonLabel: "Save",
+    resultDescription: "A new empty-username login is created",
+    expectedStorageChange: true,
+    expectedResultLogins: [
+      {
+        username: "bob",
+        password: "abc",
+      },
+      {
+        username: "",
+        password: "abc",
+      },
+    ],
+    resultCheck() {
+      Assert.equal(
+        finalLogins[0].guid,
+        savedLoginsByName.bobABC.guid,
+        "Check guid"
+      );
+      Assert.equal(
+        finalLogins[0].timeLastUsed,
+        savedLoginsByName.bobABC.timeLastUsed,
+        "Check timeLastUsed didn't change"
+      );
+      Assert.equal(
+        finalLogins[0].timePasswordChanged,
+        savedLoginsByName.bobABC.timePasswordChanged,
+        "Check timePasswordChanged didn't change"
+      );
+    },
+  },
+];
+
+for (let testData of tests) {
+  let tmp = {
+    async [testData.name]() {
+      await promptToChangePasswordTest(testData);
+    },
+  };
+  add_task(tmp[testData.name]);
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_remembering.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_remembering.js
new file mode 100644
index 0000000000..93a16c2e3c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_remembering.js
@@ -0,0 +1,1295 @@
+/*
+ * Test capture popup notifications
+ */
+
+const BRAND_BUNDLE = Services.strings.createBundle(
+  "chrome://branding/locale/brand.properties"
+);
+const BRAND_SHORT_NAME = BRAND_BUNDLE.GetStringFromName("brandShortName");
+
+let nsLoginInfo = new Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  Ci.nsILoginInfo,
+  "init"
+);
+let login1 = new nsLoginInfo(
+  "http://example.com",
+  "http://example.com",
+  null,
+  "notifyu1",
+  "notifyp1",
+  "user",
+  "pass"
+);
+let login2 = new nsLoginInfo(
+  "http://example.com",
+  "http://example.com",
+  null,
+  "",
+  "notifyp1",
+  "",
+  "pass"
+);
+let login1B = new nsLoginInfo(
+  "http://example.com",
+  "http://example.com",
+  null,
+  "notifyu1B",
+  "notifyp1B",
+  "user",
+  "pass"
+);
+let login2B = new nsLoginInfo(
+  "http://example.com",
+  "http://example.com",
+  null,
+  "",
+  "notifyp1B",
+  "",
+  "pass"
+);
+
+requestLongerTimeout(2);
+
+add_setup(async function () {
+  // Load recipes for this test.
+  let recipeParent = await LoginManagerParent.recipeParentPromise;
+  await recipeParent.load({
+    siteRecipes: [
+      {
+        hosts: ["example.org"],
+        usernameSelector: "#user",
+        passwordSelector: "#pass",
+      },
+    ],
+  });
+});
+
+add_task(async function test_remember_opens() {
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      await cleanupDoorhanger(notif);
+    }
+  );
+});
+
+add_task(async function test_clickNever() {
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.ok(notif, "got notification popup");
+      Assert.equal(
+        true,
+        Services.logins.getLoginSavingEnabled("http://example.com"),
+        "Checking for login saving enabled"
+      );
+
+      await checkDoorhangerUsernamePassword("notifyu1", "notifyp1");
+      clickDoorhangerButton(notif, NEVER_MENUITEM);
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+
+  info("Make sure Never took effect");
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger("password-save");
+      Assert.ok(!notif, "checking for no notification popup");
+      Assert.equal(
+        false,
+        Services.logins.getLoginSavingEnabled("http://example.com"),
+        "Checking for login saving disabled"
+      );
+      Services.logins.setLoginSavingEnabled("http://example.com", true);
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+});
+
+add_task(async function test_clickRemember() {
+  const storageChangedPromise = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    (_, data) => data == "addLogin"
+  );
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+
+      Assert.equal(
+        (await Services.logins.getAllLogins()).length,
+        0,
+        "Should not have any logins yet"
+      );
+
+      await checkDoorhangerUsernamePassword("notifyu1", "notifyp1");
+      let promiseNewSavedPassword = TestUtils.topicObserved(
+        "LoginStats:NewSavedPassword",
+        (subject, data) => subject == gBrowser.selectedBrowser
+      );
+      clickDoorhangerButton(notif, REMEMBER_BUTTON);
+      await promiseNewSavedPassword;
+    }
+  );
+
+  await storageChangedPromise;
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(
+    login.username,
+    "notifyu1",
+    "Check the username used on the new entry"
+  );
+  Assert.equal(
+    login.password,
+    "notifyp1",
+    "Check the password used on the new entry"
+  );
+  Assert.equal(login.timesUsed, 1, "Check times used on new entry");
+
+  info(
+    "Make sure Remember took effect and we don't prompt for an existing login"
+  );
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    function (fieldValues) {
+      // form login matches a saved login, we don't expect a notification on change or submit
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger("password-save");
+      Assert.ok(!notif, "checking for no notification popup");
+    }
+  );
+
+  logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username used");
+  Assert.equal(login.password, "notifyp1", "Check the password used");
+  Assert.equal(login.timesUsed, 2, "Check times used incremented");
+
+  checkOnlyLoginWasUsedTwice({ justChanged: false });
+
+  // remove that login
+  Services.logins.removeLogin(login1);
+  await cleanupDoorhanger();
+});
+
+/* signons.rememberSignons pref tests... */
+
+add_task(async function test_rememberSignonsFalse() {
+  info("Make sure we don't prompt with rememberSignons=false");
+  Services.prefs.setBoolPref("signon.rememberSignons", false);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger("password-save");
+      Assert.ok(!notif, "checking for no notification popup");
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+});
+
+add_task(async function test_rememberSignonsTrue() {
+  info("Make sure we prompt with rememberSignons=true");
+  Services.prefs.setBoolPref("signon.rememberSignons", true);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+});
+
+/* autocomplete=off tests... */
+
+add_task(async function test_autocompleteOffUsername() {
+  info(
+    "Check for notification popup when autocomplete=off present on username"
+  );
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_2.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(notif, "checking for notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+});
+
+add_task(async function test_autocompleteOffPassword() {
+  info(
+    "Check for notification popup when autocomplete=off present on password"
+  );
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_3.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(notif, "checking for notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+});
+
+add_task(async function test_autocompleteOffForm() {
+  info("Check for notification popup when autocomplete=off present on form");
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_4.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(notif, "checking for notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+});
+
+add_task(async function test_noPasswordField() {
+  info("Check for no notification popup when no password field present");
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_5.html",
+    function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(fieldValues.password, "null", "Checking submitted password");
+      let notif = getCaptureDoorhanger("password-save");
+      Assert.ok(!notif, "checking for no notification popup");
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+});
+
+add_task(async function test_pwOnlyNewLoginMatchesUPForm() {
+  info("Check for update popup when new existing pw-only login matches form.");
+  await Services.logins.addLoginAsync(login2);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "checking for notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.equal(
+        notif.message,
+        "Add username to saved password?",
+        "Check message"
+      );
+
+      let { panel } = PopupNotifications;
+      let passwordVisiblityToggle = panel.querySelector(
+        "#password-notification-visibilityToggle"
+      );
+      Assert.ok(
+        !passwordVisiblityToggle.hidden,
+        "Toggle visible for a recently saved pw"
+      );
+
+      await checkDoorhangerUsernamePassword("notifyu1", "notifyp1");
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+
+      Assert.ok(
+        !getCaptureDoorhanger("password-change"),
+        "popup should be gone"
+      );
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username");
+  Assert.equal(login.password, "notifyp1", "Check the password");
+  Assert.equal(login.timesUsed, 2, "Check times used");
+
+  Services.logins.removeLogin(login);
+});
+
+add_task(async function test_pwOnlyOldLoginMatchesUPForm() {
+  info("Check for update popup when old existing pw-only login matches form.");
+  await Services.logins.addLoginAsync(login2);
+
+  // Change the timePasswordChanged to be old so that the password won't be
+  // revealed in the doorhanger.
+  let oldTimeMS = new Date("2009-11-15").getTime();
+  Services.logins.modifyLogin(
+    login2,
+    LoginHelper.newPropertyBag({
+      timeCreated: oldTimeMS,
+      timeLastUsed: oldTimeMS + 1,
+      timePasswordChanged: oldTimeMS,
+    })
+  );
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "checking for notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.equal(
+        notif.message,
+        "Add username to saved password?",
+        "Check message"
+      );
+
+      let { panel } = PopupNotifications;
+      let passwordVisiblityToggle = panel.querySelector(
+        "#password-notification-visibilityToggle"
+      );
+      Assert.ok(
+        passwordVisiblityToggle.hidden,
+        "Toggle hidden for an old saved pw"
+      );
+
+      await checkDoorhangerUsernamePassword("notifyu1", "notifyp1");
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+
+      Assert.ok(
+        !getCaptureDoorhanger("password-change"),
+        "popup should be gone"
+      );
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username");
+  Assert.equal(login.password, "notifyp1", "Check the password");
+  Assert.equal(login.timesUsed, 2, "Check times used");
+
+  Services.logins.removeLogin(login);
+});
+
+add_task(async function test_pwOnlyFormMatchesLogin() {
+  info(
+    "Check for no notification popup when pw-only form matches existing login."
+  );
+  await Services.logins.addLoginAsync(login1);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_6.html",
+    function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger("password-save");
+      Assert.ok(!notif, "checking for no notification popup");
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username");
+  Assert.equal(login.password, "notifyp1", "Check the password");
+  Assert.equal(login.timesUsed, 2, "Check times used");
+
+  Services.logins.removeLogin(login1);
+});
+
+add_task(async function test_pwOnlyFormDoesntMatchExisting() {
+  info(
+    "Check for notification popup when pw-only form doesn't match existing login."
+  );
+  await Services.logins.addLoginAsync(login1B);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_6.html",
+    async function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1B", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1B", "Check the password unchanged");
+  Assert.equal(login.timesUsed, 1, "Check times used");
+
+  Services.logins.removeLogin(login1B);
+});
+
+add_task(async function test_changeUPLoginOnUPForm_dont() {
+  info("Check for change-password popup, u+p login on u+p form. (not changed)");
+  await Services.logins.addLoginAsync(login1);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_8.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "pass2",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.equal(
+        notif.message,
+        "Update password for example.com?",
+        "Check message"
+      );
+
+      await checkDoorhangerUsernamePassword("notifyu1", "pass2");
+      clickDoorhangerButton(notif, DONT_CHANGE_BUTTON);
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1", "Check the password unchanged");
+  Assert.equal(login.timesUsed, 1, "Check times used");
+
+  Services.logins.removeLogin(login1);
+});
+
+add_task(async function test_changeUPLoginOnUPForm_remove() {
+  info("Check for change-password popup, u+p login on u+p form. (remove)");
+  await Services.logins.addLoginAsync(login1);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_8.html",
+    async function (fieldValues, browser) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "pass2",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.equal(
+        notif.message,
+        "Update password for example.com?",
+        "Check message"
+      );
+
+      await checkDoorhangerUsernamePassword("notifyu1", "pass2");
+      clickDoorhangerButton(notif, REMOVE_LOGIN_MENUITEM);
+
+      // Let the hint hide itself
+      const forceClosePopup = false;
+      // Make sure confirmation hint was shown
+      info("waiting for verifyConfirmationHint");
+      await verifyConfirmationHint(
+        browser,
+        forceClosePopup,
+        "identity-icon-box"
+      );
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 0, "Should have 0 logins");
+});
+
+add_task(async function test_changeUPLoginOnUPForm_change() {
+  info("Check for change-password popup, u+p login on u+p form.");
+  await Services.logins.addLoginAsync(login1);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_8.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "pass2",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.equal(
+        notif.message,
+        "Update password for example.com?",
+        "Check message"
+      );
+
+      await checkDoorhangerUsernamePassword("notifyu1", "pass2");
+      let promiseLoginUpdateSaved = TestUtils.topicObserved(
+        "LoginStats:LoginUpdateSaved",
+        (subject, data) => subject == gBrowser.selectedBrowser
+      );
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+      await promiseLoginUpdateSaved;
+
+      Assert.ok(
+        !getCaptureDoorhanger("password-change"),
+        "popup should be gone"
+      );
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username unchanged");
+  Assert.equal(login.password, "pass2", "Check the password changed");
+  Assert.equal(login.timesUsed, 2, "Check times used");
+
+  await checkOnlyLoginWasUsedTwice({ justChanged: true });
+
+  // cleanup
+  login1.password = "pass2";
+  Services.logins.removeLogin(login1);
+  login1.password = "notifyp1";
+});
+
+add_task(async function test_changePLoginOnUPForm() {
+  info("Check for change-password popup, p-only login on u+p form (empty u).");
+  await Services.logins.addLoginAsync(login2);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_9.html",
+    async function (fieldValues) {
+      Assert.equal(fieldValues.username, "", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "pass2",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.equal(
+        notif.message,
+        "Update password for example.com?",
+        "Check msg"
+      );
+
+      await checkDoorhangerUsernamePassword("", "pass2");
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+
+      Assert.ok(
+        !getCaptureDoorhanger("password-change"),
+        "popup should be gone"
+      );
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "", "Check the username unchanged");
+  Assert.equal(login.password, "pass2", "Check the password changed");
+  Assert.equal(login.timesUsed, 2, "Check times used");
+
+  // no cleanup -- saved password to be used in the next test.
+});
+
+add_task(async function test_changePLoginOnPForm() {
+  info("Check for change-password popup, p-only login on p-only form.");
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_10.html",
+    async function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.equal(
+        notif.message,
+        "Update password for example.com?",
+        "Check msg"
+      );
+
+      await checkDoorhangerUsernamePassword("", "notifyp1");
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+
+      Assert.ok(
+        !getCaptureDoorhanger("password-change"),
+        "popup should be gone"
+      );
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1", "Check the password changed");
+  Assert.equal(login.timesUsed, 3, "Check times used");
+
+  Services.logins.removeLogin(login2);
+});
+
+add_task(async function test_checkUPSaveText() {
+  info("Check text on a user+pass notification popup");
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.ok(notif, "got notification popup");
+      // Check the text, which comes from the localized saveLoginMsg string.
+      let notificationText = notif.message;
+      let expectedText = "Save password for example.com?";
+      Assert.equal(
+        notificationText,
+        expectedText,
+        "Checking text: " + notificationText
+      );
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+});
+
+add_task(async function test_checkPSaveText() {
+  info("Check text on a pass-only notification popup");
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_6.html",
+    async function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.ok(notif, "got notification popup");
+      // Check the text, which comes from the localized saveLoginMsgNoUser string.
+      let notificationText = notif.message;
+      let expectedText = "Save password for example.com?";
+      Assert.equal(
+        notificationText,
+        expectedText,
+        "Checking text: " + notificationText
+      );
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+});
+
+add_task(async function test_capture2pw0un() {
+  info(
+    "Check for notification popup when a form with 2 password fields (no username) " +
+      "is submitted and there are no saved logins."
+  );
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_2pw_0un.html",
+    async function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      Assert.ok(notif, "got notification popup");
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should not have any logins yet"
+  );
+});
+
+add_task(async function test_change2pw0unExistingDifferentUP() {
+  info(
+    "Check for notification popup when a form with 2 password fields (no username) " +
+      "is submitted and there is a saved login with a username and different password."
+  );
+
+  await Services.logins.addLoginAsync(login1B);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_2pw_0un.html",
+    async function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1B", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1B", "Check the password unchanged");
+  Assert.equal(login.timesUsed, 1, "Check times used");
+
+  Services.logins.removeLogin(login1B);
+});
+
+add_task(async function test_change2pw0unExistingDifferentP() {
+  info(
+    "Check for notification popup when a form with 2 password fields (no username) " +
+      "is submitted and there is a saved login with no username and different password."
+  );
+
+  await Services.logins.addLoginAsync(login2B);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_2pw_0un.html",
+    async function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      await cleanupDoorhanger(notif);
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1B", "Check the password unchanged");
+  Assert.equal(login.timesUsed, 1, "Check times used");
+
+  Services.logins.removeLogin(login2B);
+});
+
+add_task(async function test_change2pw0unExistingWithSameP() {
+  info(
+    "Check for no notification popup when a form with 2 password fields (no username) " +
+      "is submitted and there is a saved login with a username and the same password."
+  );
+
+  await Services.logins.addLoginAsync(login2);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_2pw_0un.html",
+    function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger("password-change");
+      Assert.ok(!notif, "checking for no notification popup");
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1", "Check the password unchanged");
+  Assert.equal(login.timesUsed, 2, "Check times used incremented");
+
+  await checkOnlyLoginWasUsedTwice({ justChanged: false });
+
+  Services.logins.removeLogin(login2);
+});
+
+add_task(async function test_changeUPLoginOnPUpdateForm() {
+  info("Check for change-password popup, u+p login on password update form.");
+  await Services.logins.addLoginAsync(login1);
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_change_p.html",
+    async function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "pass2",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-change");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+
+      await checkDoorhangerUsernamePassword("notifyu1", "pass2");
+      clickDoorhangerButton(notif, CHANGE_BUTTON);
+
+      Assert.ok(
+        !getCaptureDoorhanger("password-change"),
+        "popup should be gone"
+      );
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username unchanged");
+  Assert.equal(login.password, "pass2", "Check the password changed");
+  Assert.equal(login.timesUsed, 2, "Check times used");
+
+  await checkOnlyLoginWasUsedTwice({ justChanged: true });
+
+  // cleanup
+  login1.password = "pass2";
+  Services.logins.removeLogin(login1);
+  login1.password = "notifyp1";
+});
+
+add_task(async function test_recipeCaptureFields_NewLogin() {
+  info(
+    "Check that we capture the proper fields when a field recipe is in use."
+  );
+
+  const storageChangedPromise = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    (_, data) => data == "addLogin"
+  );
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_2pw_1un_1text.html",
+    async function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(notif, "got notification popup");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+
+      // Sanity check, no logins should exist yet.
+      let logins = await Services.logins.getAllLogins();
+      Assert.equal(logins.length, 0, "Should not have any logins yet");
+
+      await checkDoorhangerUsernamePassword("notifyu1", "notifyp1");
+      clickDoorhangerButton(notif, REMEMBER_BUTTON);
+    },
+    "http://example.org"
+  ); // The recipe is for example.org
+
+  await storageChangedPromise;
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1", "Check the password unchanged");
+  Assert.equal(login.timesUsed, 1, "Check times used");
+});
+
+add_task(async function test_recipeCaptureFields_ExistingLogin() {
+  info(
+    "Check that we capture the proper fields when a field recipe is in use " +
+      "and there is a matching login"
+  );
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_2pw_1un_1text.html",
+    function (fieldValues) {
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger("password-save");
+      Assert.ok(!notif, "checking for no notification popup");
+    },
+    "http://example.org"
+  );
+
+  await checkOnlyLoginWasUsedTwice({ justChanged: false });
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1", "Check the password unchanged");
+  Assert.equal(login.timesUsed, 2, "Check times used incremented");
+
+  Services.logins.removeAllUserFacingLogins();
+});
+
+add_task(async function test_saveUsingEnter() {
+  async function testWithTextboxSelector(fieldSelector) {
+    const storageChangedPromise = TestUtils.topicObserved(
+      "passwordmgr-storage-changed",
+      (_, data) => data == "addLogin"
+    );
+
+    info("Waiting for form submit and doorhanger interaction");
+    await testSubmittingLoginFormHTTP(
+      "subtst_notifications_1.html",
+      async function (fieldValues) {
+        Assert.equal(
+          fieldValues.username,
+          "notifyu1",
+          "Checking submitted username"
+        );
+        Assert.equal(
+          fieldValues.password,
+          "notifyp1",
+          "Checking submitted password"
+        );
+        let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+        Assert.ok(notif, "got notification popup");
+        Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+        Assert.equal(
+          (await Services.logins.getAllLogins()).length,
+          0,
+          "Should not have any logins yet"
+        );
+        await checkDoorhangerUsernamePassword("notifyu1", "notifyp1");
+        let notificationElement = PopupNotifications.panel.childNodes[0];
+        let textbox = notificationElement.querySelector(fieldSelector);
+        textbox.focus();
+        await EventUtils.synthesizeKey("KEY_Enter");
+      }
+    );
+
+    await storageChangedPromise;
+
+    let logins = await Services.logins.getAllLogins();
+    Assert.equal(logins.length, 1, "Should only have 1 login");
+    let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+    Assert.equal(
+      login.username,
+      "notifyu1",
+      "Check the username used on the new entry"
+    );
+    Assert.equal(
+      login.password,
+      "notifyp1",
+      "Check the password used on the new entry"
+    );
+    Assert.equal(login.timesUsed, 1, "Check times used on new entry");
+
+    Services.logins.removeAllUserFacingLogins();
+  }
+
+  await testWithTextboxSelector("#password-notification-password");
+  await testWithTextboxSelector("#password-notification-username");
+});
+
+add_task(async function test_noShowPasswordOnDismissal() {
+  info("Check for no Show Password field when the doorhanger is dismissed");
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    async function (fieldValues) {
+      info("Opening popup");
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      let { panel } = PopupNotifications;
+
+      info("Hiding popup.");
+      let promiseHidden = BrowserTestUtils.waitForEvent(panel, "popuphidden");
+      panel.hidePopup();
+      await promiseHidden;
+
+      info("Clicking on anchor to reshow popup.");
+      let promiseShown = BrowserTestUtils.waitForEvent(panel, "popupshown");
+      notif.anchorElement.click();
+      await promiseShown;
+
+      let passwordVisiblityToggle = panel.querySelector(
+        "#password-notification-visibilityToggle"
+      );
+      Assert.equal(
+        passwordVisiblityToggle.hidden,
+        true,
+        "Check that the Show Password field is Hidden"
+      );
+      await cleanupDoorhanger(notif);
+    }
+  );
+});
+
+add_task(async function test_showPasswordOn1stOpenOfDismissedByDefault() {
+  info("Show Password toggle when the doorhanger is dismissed by default");
+
+  await testSubmittingLoginFormHTTP(
+    "subtst_notifications_1.html",
+    async function (fieldValues) {
+      info("Opening popup");
+      let notif = await getCaptureDoorhangerThatMayOpen("password-save");
+      Assert.ok(!notif.dismissed, "doorhanger is not dismissed");
+      let { panel } = PopupNotifications;
+
+      info("Hiding popup.");
+      let promiseHidden = BrowserTestUtils.waitForEvent(panel, "popuphidden");
+      panel.hidePopup();
+      await promiseHidden;
+
+      info("Clicking on anchor to reshow popup.");
+      let promiseShown = BrowserTestUtils.waitForEvent(panel, "popupshown");
+      notif.anchorElement.click();
+      await promiseShown;
+
+      let passwordVisiblityToggle = panel.querySelector(
+        "#password-notification-visibilityToggle"
+      );
+      Assert.equal(
+        passwordVisiblityToggle.hidden,
+        true,
+        "Check that the Show Password field is Hidden"
+      );
+      await cleanupDoorhanger(notif);
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_replace_dismissed_with_visible_while_opening.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_replace_dismissed_with_visible_while_opening.js
new file mode 100644
index 0000000000..401e0add1b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_replace_dismissed_with_visible_while_opening.js
@@ -0,0 +1,65 @@
+/**
+ * Replacing a dismissed doorhanger with a visible one while it's opening.
+ *
+ * There are various races between popup notification callbacks to catch with this.
+ * This can happen in the real world by blurring an edited login field by clicking on the login doorhanger.
+ */
+
+XPCOMUtils.defineLazyServiceGetter(
+  this,
+  "prompterSvc",
+  "@mozilla.org/login-manager/prompter;1",
+  Ci.nsILoginManagerPrompter
+);
+
+add_task(async function test_replaceDismissedWithVisibleWhileOpening() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "https://example.com",
+    },
+    async function load(browser) {
+      info("Show a dismissed save doorhanger");
+      prompterSvc.promptToSavePassword(
+        browser,
+        LoginTestUtils.testData.formLogin({}),
+        true,
+        false,
+        null
+      );
+      let doorhanger = await waitForDoorhanger(browser, "password-save");
+      Assert.ok(doorhanger, "Got doorhanger");
+      EventUtils.synthesizeMouseAtCenter(doorhanger.anchorElement, {});
+      await BrowserTestUtils.waitForEvent(
+        PopupNotifications.panel,
+        "popupshowing"
+      );
+      await checkDoorhangerUsernamePassword("the username", "the password");
+      info(
+        "Replace the doorhanger with a non-dismissed one immediately after clicking to open"
+      );
+      prompterSvc.promptToSavePassword(
+        browser,
+        LoginTestUtils.testData.formLogin({}),
+        true,
+        false,
+        null
+      );
+      await Promise.race([
+        BrowserTestUtils.waitForCondition(() => {
+          if (
+            document.getElementById("password-notification-username").value !=
+              "the username" ||
+            document.getElementById("password-notification-password").value !=
+              "the password"
+          ) {
+            return Promise.reject("Field changed to incorrect values");
+          }
+          return false;
+        }, "See if username/password values change to incorrect values"),
+        // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+        new Promise(resolve => setTimeout(resolve, 1000)),
+      ]);
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_save_password.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_save_password.js
new file mode 100644
index 0000000000..50316094b0
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_save_password.js
@@ -0,0 +1,159 @@
+/**
+ * Test that the doorhanger notification for password saving is populated with
+ * the correct values in various password capture cases.
+ */
+
+const testCases = [
+  {
+    name: "No saved logins, username and password",
+    username: "username",
+    password: "password",
+    expectOutcome: [
+      {
+        username: "username",
+        password: "password",
+      },
+    ],
+  },
+  {
+    name: "No saved logins, password with empty username",
+    username: "",
+    password: "password",
+    expectOutcome: [
+      {
+        username: "",
+        password: "password",
+      },
+    ],
+  },
+  {
+    name: "Saved login with username, update password",
+    username: "username",
+    oldPassword: "password",
+    password: "newPassword",
+    expectOutcome: [
+      {
+        username: "username",
+        password: "newPassword",
+      },
+    ],
+  },
+  {
+    name: "Saved login with no username, update password",
+    username: "",
+    oldPassword: "password",
+    password: "newPassword",
+    expectOutcome: [
+      {
+        username: "",
+        password: "newPassword",
+      },
+    ],
+  },
+  {
+    name: "Saved login with no username, add username and different password",
+    oldUsername: "",
+    username: "username",
+    oldPassword: "password",
+    password: "newPassword",
+    expectOutcome: [
+      {
+        username: "",
+        password: "password",
+      },
+      {
+        username: "username",
+        password: "newPassword",
+      },
+    ],
+  },
+];
+
+for (let testData of testCases) {
+  let tmp = {
+    async [testData.name]() {
+      info("testing with: " + JSON.stringify(testData));
+      await test_save_change(testData);
+    },
+  };
+  add_task(tmp[testData.name]);
+}
+
+async function test_save_change(testData) {
+  let { oldUsername, username, oldPassword, password, expectOutcome } =
+    testData;
+  // Add a login for the origin of the form if testing a change notification.
+  if (oldPassword) {
+    await Services.logins.addLoginAsync(
+      LoginTestUtils.testData.formLogin({
+        origin: "https://example.com",
+        formActionOrigin: "https://example.com",
+        username: typeof oldUsername !== "undefined" ? oldUsername : username,
+        password: oldPassword,
+      })
+    );
+  }
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url:
+        "https://example.com/browser/toolkit/components/" +
+        "passwordmgr/test/browser/form_basic.html",
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+      // Update the form with credentials from the test case.
+      info(`update form with username: ${username}, password: ${password}`);
+      await changeContentFormValues(browser, {
+        "#form-basic-username": username,
+        "#form-basic-password": password,
+      });
+
+      // Submit the form with the new credentials. This will cause the doorhanger
+      // notification to be displayed.
+      let formSubmittedPromise = listenForTestNotification("ShowDoorhanger");
+      await SpecialPowers.spawn(browser, [], async function () {
+        let doc = this.content.document;
+        doc.getElementById("form-basic").submit();
+      });
+      await formSubmittedPromise;
+
+      // Simulate the action on the notification to request the login to be
+      // saved, and wait for the data to be updated or saved based on the type
+      // of operation we expect.
+      let expectedNotification, expectedDoorhanger;
+      if (oldPassword !== undefined && oldUsername !== undefined) {
+        expectedNotification = "addLogin";
+        expectedDoorhanger = "password-save";
+      } else if (oldPassword !== undefined) {
+        expectedNotification = "modifyLogin";
+        expectedDoorhanger = "password-change";
+      } else {
+        expectedNotification = "addLogin";
+        expectedDoorhanger = "password-save";
+      }
+
+      info("Waiting for doorhanger of type: " + expectedDoorhanger);
+      let notif = await waitForDoorhanger(browser, expectedDoorhanger);
+
+      // Check the actual content of the popup notification.
+      await checkDoorhangerUsernamePassword(username, password);
+
+      let promiseLogin = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (_, data) => data == expectedNotification
+      );
+      await clickDoorhangerButton(notif, REMEMBER_BUTTON);
+      await promiseLogin;
+      await cleanupDoorhanger(notif); // clean slate for the next test
+
+      // Check that the values in the database match the expected values.
+      await verifyLogins(expectOutcome);
+    }
+  );
+
+  // Clean up the database before the next test case is executed.
+  Services.logins.removeAllUserFacingLogins();
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_submit_telemetry.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_submit_telemetry.js
new file mode 100644
index 0000000000..97353007ac
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_submit_telemetry.js
@@ -0,0 +1,387 @@
+/**
+ * Test that doorhanger submit telemetry is sent when the user saves/updates.
+ */
+
+add_setup(function () {
+  // This test used to rely on the initial timer of
+  // TestUtils.waitForCondition. See bug 1695395.
+  // The test is perma-fail on Linux asan opt without this.
+  let originalWaitForCondition = TestUtils.waitForCondition;
+  TestUtils.waitForCondition = async function (
+    condition,
+    msg,
+    interval = 100,
+    maxTries = 50
+  ) {
+    // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+    await new Promise(resolve => setTimeout(resolve, 100));
+
+    return originalWaitForCondition(condition, msg, interval, maxTries);
+  };
+  registerCleanupFunction(function () {
+    TestUtils.waitForCondition = originalWaitForCondition;
+  });
+});
+
+const PAGE_USERNAME_SELECTOR = "#form-basic-username";
+const PAGE_PASSWORD_SELECTOR = "#form-basic-password";
+
+const TEST_CASES = [
+  {
+    description:
+      "Saving a new login from page values without modification sends a 'no modification' event",
+    savedLogin: undefined,
+    userActions: [
+      {
+        pageChanges: {
+          username: "pageUn",
+          password: "pagePw",
+        },
+        doorhangerChanges: [],
+      },
+    ],
+    expectedEvents: [
+      {
+        type: "save",
+        ping: {
+          did_edit_un: "false",
+          did_select_un: "false",
+          did_edit_pw: "false",
+          did_select_pw: "false",
+        },
+      },
+    ],
+  },
+  /////////////////
+  {
+    description: "Saving two logins sends two events",
+    userActions: [
+      {
+        pageChanges: { password: "pagePw" },
+        doorhangerChanges: [
+          {
+            typedUsername: "doorhangerUn",
+          },
+        ],
+      },
+      {
+        pageChanges: { password: "pagePw2" },
+        doorhangerChanges: [
+          {
+            typedPassword: "doorhangerPw",
+          },
+        ],
+      },
+    ],
+    expectedEvents: [
+      {
+        type: "save",
+        ping: {
+          did_edit_un: "true",
+          did_select_un: "false",
+          did_edit_pw: "false",
+          did_select_pw: "false",
+        },
+      },
+      {
+        type: "update",
+        ping: {
+          did_edit_un: "false",
+          did_select_un: "false",
+          did_edit_pw: "true",
+          did_select_pw: "false",
+        },
+      },
+    ],
+  },
+  /////////////////
+  {
+    description: "Updating a doorhanger password sends a 'pw updated' event",
+    savedLogin: {
+      username: "savedUn",
+      password: "savedPw",
+    },
+    userActions: [
+      {
+        pageChanges: { password: "pagePw" },
+        doorhangerChanges: [
+          {
+            typedPassword: "doorhangerPw",
+          },
+        ],
+      },
+    ],
+    expectedEvents: [
+      {
+        type: "update",
+        ping: {
+          did_edit_un: "false",
+          did_select_un: "false",
+          did_edit_pw: "true",
+          did_select_pw: "false",
+        },
+      },
+    ],
+  },
+  /////////////////
+  {
+    description:
+      "Saving a new username with an existing password sends a 'un updated' event",
+    savedLogin: {
+      username: "savedUn",
+      password: "savedPw",
+    },
+    userActions: [
+      {
+        pageChanges: { password: "pagePw" },
+        doorhangerChanges: [
+          {
+            typedUsername: "doorhangerUn",
+          },
+        ],
+      },
+    ],
+    expectedEvents: [
+      {
+        type: "update",
+        ping: {
+          did_edit_un: "true",
+          did_select_un: "false",
+          did_edit_pw: "false",
+          did_select_pw: "false",
+        },
+      },
+    ],
+  },
+  ///////////////
+  {
+    description: "selecting a saved username sends a 'not edited' event",
+    savedLogin: {
+      username: "savedUn",
+      password: "savedPw",
+    },
+    userActions: [
+      {
+        pageChanges: { password: "pagePw" },
+        doorhangerChanges: [
+          {
+            selectUsername: "savedUn",
+          },
+        ],
+      },
+    ],
+    expectedEvents: [
+      {
+        type: "update",
+        ping: {
+          did_edit_un: "false",
+          did_select_un: "true",
+          did_edit_pw: "false",
+          did_select_pw: "false",
+        },
+      },
+    ],
+  },
+  /////////////////
+  {
+    description:
+      "typing a new username then selecting a saved username sends a 'not edited' event",
+    savedLogin: {
+      username: "savedUn",
+      password: "savedPw",
+    },
+    userActions: [
+      {
+        pageChanges: { password: "pagePw" },
+        doorhangerChanges: [
+          {
+            typedUsername: "doorhangerTypedUn",
+          },
+          {
+            selectUsername: "savedUn",
+          },
+        ],
+      },
+    ],
+    expectedEvents: [
+      {
+        type: "update",
+        ping: {
+          did_edit_un: "false",
+          did_select_un: "true",
+          did_edit_pw: "false",
+          did_select_pw: "false",
+        },
+      },
+    ],
+  },
+  /////////////////
+  {
+    description:
+      "selecting a saved username then typing a new username sends an 'edited' event",
+    savedLogin: {
+      username: "savedUn",
+      password: "savedPw",
+    },
+    userActions: [
+      {
+        pageChanges: { password: "pagePw" },
+        doorhangerChanges: [
+          {
+            selectUsername: "savedUn",
+          },
+          {
+            typedUsername: "doorhangerTypedUn",
+          },
+        ],
+      },
+    ],
+    expectedEvents: [
+      {
+        type: "update",
+        ping: {
+          did_edit_un: "true",
+          did_select_un: "false",
+          did_edit_pw: "false",
+          did_select_pw: "false",
+        },
+      },
+    ],
+  },
+  /////////////////
+];
+
+for (let testData of TEST_CASES) {
+  let tmp = {
+    async [testData.description]() {
+      info("testing with: " + JSON.stringify(testData));
+      await test_submit_telemetry(testData);
+    },
+  };
+  add_task(tmp[testData.description]);
+}
+
+function _validateTestCase(tc) {
+  for (let event of tc.expectedEvents) {
+    Assert.ok(
+      !(event.ping.did_edit_un && event.ping.did_select_un),
+      "'did_edit_un' and 'did_select_un' can never be true at the same time"
+    );
+    Assert.ok(
+      !(event.ping.did_edit_pw && event.ping.did_select_pw),
+      "'did_edit_pw' and 'did_select_pw' can never be true at the same time"
+    );
+  }
+}
+
+async function test_submit_telemetry(tc) {
+  if (tc.savedLogin) {
+    await Services.logins.addLoginAsync(
+      LoginTestUtils.testData.formLogin({
+        origin: "https://example.com",
+        formActionOrigin: "https://example.com",
+        username: tc.savedLogin.username,
+        password: tc.savedLogin.password,
+      })
+    );
+  }
+
+  let notif;
+  for (let userAction of tc.userActions) {
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url:
+          "https://example.com/browser/toolkit/components/" +
+          "passwordmgr/test/browser/form_basic.html",
+      },
+      async function (browser) {
+        await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+        if (userAction.pageChanges) {
+          info(
+            `Update form with changes: ${JSON.stringify(
+              userAction.pageChanges
+            )}`
+          );
+          let changeTo = {};
+          if (userAction.pageChanges.username) {
+            changeTo[PAGE_USERNAME_SELECTOR] = userAction.pageChanges.username;
+          }
+          if (userAction.pageChanges.password) {
+            changeTo[PAGE_PASSWORD_SELECTOR] = userAction.pageChanges.password;
+          }
+
+          await changeContentFormValues(browser, changeTo);
+        }
+
+        info("Submitting form");
+        let formSubmittedPromise = listenForTestNotification("ShowDoorhanger");
+        await SpecialPowers.spawn(browser, [], async function () {
+          let doc = this.content.document;
+          doc.getElementById("form-basic").submit();
+        });
+        await formSubmittedPromise;
+
+        let saveDoorhanger = waitForDoorhanger(browser, "password-save");
+        let updateDoorhanger = waitForDoorhanger(browser, "password-change");
+        notif = await Promise.race([saveDoorhanger, updateDoorhanger]);
+
+        if (PopupNotifications.panel.state !== "open") {
+          await BrowserTestUtils.waitForEvent(
+            PopupNotifications.panel,
+            "popupshown"
+          );
+        }
+
+        if (userAction.doorhangerChanges) {
+          for (let doorhangerChange of userAction.doorhangerChanges) {
+            if (
+              doorhangerChange.typedUsername ||
+              doorhangerChange.typedPassword
+            ) {
+              await updateDoorhangerInputValues({
+                username: doorhangerChange.typedUsername,
+                password: doorhangerChange.typedPassword,
+              });
+            }
+
+            if (doorhangerChange.selectUsername) {
+              await selectDoorhangerUsername(doorhangerChange.selectUsername);
+            }
+            if (doorhangerChange.selectPassword) {
+              await selectDoorhangerPassword(doorhangerChange.selectPassword);
+            }
+          }
+        }
+
+        info("Waiting for doorhanger");
+        await clickDoorhangerButton(notif, REMEMBER_BUTTON);
+      }
+    );
+  }
+
+  let expectedEvents = tc.expectedEvents.map(expectedEvent => [
+    "pwmgr",
+    "doorhanger_submitted",
+    expectedEvent.type,
+    null,
+    expectedEvent.ping,
+  ]);
+
+  await LoginTestUtils.telemetry.waitForEventCount(
+    expectedEvents.length,
+    "parent",
+    "pwmgr",
+    "doorhanger_submitted"
+  );
+  TelemetryTestUtils.assertEvents(
+    expectedEvents,
+    { category: "pwmgr", method: "doorhanger_submitted" },
+    { clear: true }
+  );
+
+  // Clean up the database before the next test case is executed.
+  await cleanupDoorhanger(notif);
+  Services.logins.removeAllUserFacingLogins();
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_target_blank.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_target_blank.js
new file mode 100644
index 0000000000..39b98db93b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_target_blank.js
@@ -0,0 +1,94 @@
+/**
+ * Test capture popup notifications when the login form uses target="_blank"
+ */
+
+add_setup(async function () {
+  await SimpleTest.promiseFocus(window);
+});
+
+add_task(async function test_saveTargetBlank() {
+  // This test submits the form to a new tab using target="_blank".
+  let url = "subtst_notifications_12_target_blank.html?notifyu3|notifyp3||";
+  let notifShownPromise = BrowserTestUtils.waitForEvent(
+    PopupNotifications.panel,
+    "popupshown"
+  );
+
+  let submissionTabPromise = BrowserTestUtils.waitForNewTab(
+    gBrowser,
+    url => {
+      info(url);
+      return url.includes("formsubmit.sjs");
+    },
+    false,
+    true
+  );
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "http://mochi.test:8888" + DIRECTORY_PATH + url,
+    },
+    async function () {
+      // For now the doorhanger appears in the previous tab but it should maybe
+      // appear in the new tab from target="_blank"?
+      BrowserTestUtils.removeTab(await submissionTabPromise);
+
+      let notif = await TestUtils.waitForCondition(
+        () =>
+          getCaptureDoorhangerThatMayOpen(
+            "password-save",
+            PopupNotifications,
+            gBrowser.selectedBrowser
+          ),
+        "Waiting for doorhanger"
+      );
+      Assert.ok(notif, "got notification popup");
+
+      EventUtils.synthesizeMouseAtCenter(notif.anchorElement, {});
+      await notifShownPromise;
+      await checkDoorhangerUsernamePassword("notifyu3", "notifyp3");
+      let storageChangedPromised = TestUtils.topicObserved(
+        "passwordmgr-storage-changed",
+        (subject, data) => data != "removeLogin"
+      );
+
+      clickDoorhangerButton(notif, REMEMBER_BUTTON);
+      await storageChangedPromised;
+      BrowserTestUtils.removeTab(gBrowser.selectedTab);
+    }
+  );
+
+  // Check result of clicking Remember
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login now");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(
+    login.username,
+    "notifyu3",
+    "Check the username used on the new entry"
+  );
+  Assert.equal(
+    login.password,
+    "notifyp3",
+    "Check the password used on the new entry"
+  );
+  Assert.equal(login.timesUsed, 1, "Check times used on new entry");
+
+  // Check for stale values in the doorhanger <input> after closing.
+  let usernameField = document.getElementById("password-notification-username");
+  todo_is(
+    usernameField.value,
+    "",
+    "Check the username field doesn't have a stale value"
+  );
+  let passwordField = document.getElementById("password-notification-password");
+  todo_is(
+    passwordField.value,
+    "",
+    "Check the password field doesn't have a stale value"
+  );
+
+  // Cleanup
+  Services.logins.removeLogin(login);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_toggles.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_toggles.js
new file mode 100644
index 0000000000..e6c09c0382
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_toggles.js
@@ -0,0 +1,478 @@
+/* eslint no-shadow:"off" */
+
+const passwordInputSelector = "#form-basic-password";
+const usernameInputSelector = "#form-basic-username";
+const FORM_URL =
+  "https://example.com/browser/toolkit/components/passwordmgr/test/browser/form_basic.html";
+
+add_setup(async function () {
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.rememberSignons.visibilityToggle", true]],
+  });
+});
+
+let testCases = [
+  {
+    /* Test that the doorhanger password field shows plain or * text
+     * when the checkbox is checked.
+     */
+    name: "test_toggle_password",
+    logins: [],
+    enabledPrimaryPassword: false,
+    formDefaults: {},
+    formChanges: {
+      [passwordInputSelector]: "pw",
+      [usernameInputSelector]: "username",
+    },
+    expected: {
+      initialForm: {
+        username: "",
+        password: "",
+      },
+      passwordChangedDoorhanger: null,
+      submitDoorhanger: {
+        type: "password-save",
+        dismissed: false,
+        username: "username",
+        password: "pw",
+        toggleVisible: true,
+        initialToggleState: {
+          inputType: "password",
+          toggleChecked: false,
+        },
+        afterToggleClick0: {
+          inputType: "text",
+          toggleChecked: true,
+        },
+        afterToggleClick1: {
+          inputType: "password",
+          toggleChecked: false,
+        },
+      },
+    },
+  },
+  {
+    /* Test that the doorhanger password toggle checkbox is disabled
+     * when the primary password is set.
+     */
+    name: "test_checkbox_disabled_if_has_primary_password",
+    logins: [],
+    enabledPrimaryPassword: true,
+    formDefaults: {},
+    formChanges: {
+      [passwordInputSelector]: "pass",
+      [usernameInputSelector]: "username",
+    },
+    expected: {
+      initialForm: {
+        username: "",
+        password: "",
+      },
+      passwordChangedDoorhanger: null,
+      submitDoorhanger: {
+        type: "password-save",
+        dismissed: false,
+        username: "username",
+        password: "pass",
+        toggleVisible: false,
+        initialToggleState: {
+          inputType: "password",
+          toggleChecked: false,
+        },
+      },
+    },
+  },
+  {
+    /* Test that the reveal password checkbox is hidden when editing the
+     * password of an autofilled login
+     */
+    name: "test_edit_autofilled_password",
+    logins: [{ username: "username1", password: "password" }],
+    formDefaults: {},
+    formChanges: {
+      [passwordInputSelector]: "password!",
+    },
+    expected: {
+      initialForm: {
+        username: "username1",
+        password: "password",
+      },
+      passwordChangedDoorhanger: {
+        type: "password-change",
+        dismissed: true,
+        username: "username1",
+        password: "password!",
+        toggleVisible: false,
+        initialToggleState: {
+          inputType: "password",
+          toggleChecked: false,
+        },
+      },
+      submitDoorhanger: {
+        type: "password-change",
+        dismissed: false,
+        username: "username1",
+        password: "password!",
+        toggleVisible: false,
+        initialToggleState: {
+          inputType: "password",
+          toggleChecked: false,
+        },
+      },
+    },
+  },
+  {
+    /* Test that the reveal password checkbox is shown when editing the
+     * password of a login that has been autofilled and then deleted
+     */
+    name: "test_autofilled_cleared_then_updated_password",
+    logins: [{ username: "username1", password: "password" }],
+    formDefaults: {},
+    formChanges: [
+      {
+        [passwordInputSelector]: "",
+      },
+      {
+        [passwordInputSelector]: "password!",
+      },
+    ],
+    expected: {
+      initialForm: {
+        username: "username1",
+        password: "password",
+      },
+      passwordChangedDoorhanger: {
+        type: "password-change",
+        dismissed: true,
+        username: "username1",
+        password: "password!",
+        toggleVisible: true,
+        initialToggleState: {
+          inputType: "password",
+          toggleChecked: false,
+        },
+      },
+      submitDoorhanger: {
+        type: "password-change",
+        dismissed: false,
+        username: "username1",
+        password: "password!",
+        toggleVisible: true,
+        initialToggleState: {
+          inputType: "password",
+          toggleChecked: false,
+        },
+      },
+    },
+  },
+  {
+    /* Test that the reveal password checkbox is hidden when editing the
+     * username of an autofilled login
+     */
+    name: "test_edit_autofilled_username",
+    logins: [{ username: "username1", password: "password" }],
+    formDefaults: {},
+    formChanges: {
+      [usernameInputSelector]: "username2",
+    },
+    expected: {
+      initialForm: {
+        username: "username1",
+        password: "password",
+      },
+      passwordChangedDoorhanger: {
+        type: "password-save",
+        dismissed: true,
+        username: "username2",
+        password: "password",
+        toggleVisible: false,
+        initialToggleState: {
+          inputType: "password",
+          toggleChecked: false,
+        },
+      },
+      submitDoorhanger: {
+        type: "password-save",
+        dismissed: false,
+        username: "username2",
+        password: "password",
+        toggleVisible: false,
+        initialToggleState: {
+          inputType: "password",
+          toggleChecked: false,
+        },
+      },
+    },
+  },
+];
+
+for (let testData of testCases) {
+  if (testData.skip) {
+    info("Skipping test:", testData.name);
+    continue;
+  }
+  let tmp = {
+    async [testData.name]() {
+      await testDoorhangerToggles(testData);
+    },
+  };
+  add_task(tmp[testData.name]);
+}
+
+/**
+ * Set initial test conditions,
+ * Load and populate the form,
+ * Submit it and verify doorhanger toggle behavior
+ */
+async function testDoorhangerToggles({
+  logins = [],
+  formDefaults = {},
+  formChanges = {},
+  expected,
+  enabledPrimaryPassword,
+}) {
+  formChanges = Array.isArray(formChanges) ? formChanges : [formChanges];
+
+  for (let login of logins) {
+    await LoginTestUtils.addLogin(login);
+  }
+  if (enabledPrimaryPassword) {
+    LoginTestUtils.primaryPassword.enable();
+  }
+  let formProcessedPromise = listenForTestNotification("FormProcessed");
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: FORM_URL,
+    },
+    async function (browser) {
+      info(`Opened tab with url: ${FORM_URL}, waiting for focus`);
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      info("Waiting for form-processed message");
+      await formProcessedPromise;
+      await initForm(browser, formDefaults);
+      await checkForm(browser, expected.initialForm);
+      info("form checked");
+
+      // some tests check the dismissed doorhanger from editing the password
+      let formChanged = expected.passwordChangedDoorhanger
+        ? listenForTestNotification("PasswordEditedOrGenerated")
+        : Promise.resolve();
+      for (let change of formChanges) {
+        await changeContentFormValues(browser, change, {
+          method: "paste_text",
+        });
+      }
+
+      await formChanged;
+
+      if (expected.passwordChangedDoorhanger) {
+        let expectedDoorhanger = expected.passwordChangedDoorhanger;
+        info("Verifying dismissed doorhanger from password change");
+        let notif = await waitForDoorhanger(browser, expectedDoorhanger.type);
+        Assert.ok(notif, "got notification popup");
+        Assert.equal(
+          notif.dismissed,
+          expectedDoorhanger.dismissed,
+          "Check notification dismissed property"
+        );
+        let { panel } = browser.ownerGlobal.PopupNotifications;
+        // we will open dismissed doorhanger to check panel contents
+        Assert.equal(panel.state, "closed", "Panel is initially closed");
+        let promiseShown = BrowserTestUtils.waitForEvent(panel, "popupshown");
+        info("Opening the doorhanger popup");
+        // synthesize click on anchor as this also blurs the form field triggering
+        // a change event
+        EventUtils.synthesizeMouseAtCenter(notif.anchorElement, {});
+        await promiseShown;
+        await TestUtils.waitForTick();
+        Assert.ok(
+          panel.children.length,
+          `Check the popup has at least one notification (${panel.children.length})`
+        );
+
+        // Check the password-changed-capture doorhanger contents & behaviour
+        info("Verifying the doorhanger");
+        await verifyDoorhangerToggles(browser, notif, expectedDoorhanger);
+        await hideDoorhangerPopup(notif);
+      }
+
+      if (expected.submitDoorhanger) {
+        let expectedDoorhanger = expected.submitDoorhanger;
+        let { panel } = browser.ownerGlobal.PopupNotifications;
+        // submit the form and wait for the doorhanger
+        info("Submitting the form");
+        let submittedPromise = listenForTestNotification("ShowDoorhanger");
+        let promiseShown = BrowserTestUtils.waitForEvent(panel, "popupshown");
+        await submitForm(browser, "/");
+        await submittedPromise;
+        info("Waiting for doorhanger popup to open");
+        await promiseShown;
+        let notif = await getCaptureDoorhanger(expectedDoorhanger.type);
+        Assert.ok(notif, "got notification popup");
+        Assert.equal(
+          notif.dismissed,
+          expectedDoorhanger.dismissed,
+          "Check notification dismissed property"
+        );
+        Assert.ok(
+          panel.children.length,
+          `Check the popup has at least one notification (${panel.children.length})`
+        );
+
+        // Check the submit-capture doorhanger contents & behaviour
+        info("Verifying the submit doorhanger");
+        await verifyDoorhangerToggles(browser, notif, expectedDoorhanger);
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+  await LoginTestUtils.clearData();
+  if (enabledPrimaryPassword) {
+    LoginTestUtils.primaryPassword.disable();
+  }
+  await cleanupPasswordNotifications();
+}
+
+// --------------------------------------------------------------------
+// Helpers
+
+async function verifyDoorhangerToggles(browser, notif, expected) {
+  let { initialToggleState, afterToggleClick0, afterToggleClick1 } = expected;
+
+  let { panel } = browser.ownerGlobal.PopupNotifications;
+  let notificationElement = panel.childNodes[0];
+  let passwordTextbox = notificationElement.querySelector(
+    "#password-notification-password"
+  );
+  let toggleCheckbox = notificationElement.querySelector(
+    "#password-notification-visibilityToggle"
+  );
+  Assert.equal(panel.state, "open", "Panel is open");
+  Assert.ok(
+    BrowserTestUtils.isVisible(passwordTextbox),
+    "The doorhanger password field is visible"
+  );
+
+  await checkDoorhangerUsernamePassword(expected.username, expected.password);
+  if (expected.toggleVisible) {
+    Assert.ok(
+      BrowserTestUtils.isVisible(toggleCheckbox),
+      "The visibility checkbox is shown"
+    );
+  } else {
+    Assert.ok(
+      BrowserTestUtils.isHidden(toggleCheckbox),
+      "The visibility checkbox is hidden"
+    );
+  }
+
+  if (initialToggleState) {
+    Assert.equal(
+      toggleCheckbox.checked,
+      initialToggleState.toggleChecked,
+      `Initially, toggle is ${
+        initialToggleState.toggleChecked ? "checked" : "unchecked"
+      }`
+    );
+    Assert.equal(
+      passwordTextbox.type,
+      initialToggleState.inputType,
+      `Initially, password input has type: ${initialToggleState.inputType}`
+    );
+  }
+  if (afterToggleClick0) {
+    Assert.ok(
+      !toggleCheckbox.hidden,
+      "The checkbox shouldnt be hidden when clicking on it"
+    );
+    info("Clicking on the visibility toggle");
+    await EventUtils.synthesizeMouseAtCenter(toggleCheckbox, {});
+    await TestUtils.waitForTick();
+    Assert.equal(
+      toggleCheckbox.checked,
+      afterToggleClick0.toggleChecked,
+      `After 1st click, expect toggle to be checked? ${afterToggleClick0.toggleChecked}, actual: ${toggleCheckbox.checked}`
+    );
+    Assert.equal(
+      passwordTextbox.type,
+      afterToggleClick0.inputType,
+      `After 1st click, expect password input to have type: ${afterToggleClick0.inputType}`
+    );
+  }
+  if (afterToggleClick1) {
+    Assert.ok(
+      !toggleCheckbox.hidden,
+      "The checkbox shouldnt be hidden when clicking on it"
+    );
+    info("Clicking on the visibility toggle again");
+    await EventUtils.synthesizeMouseAtCenter(toggleCheckbox, {});
+    await TestUtils.waitForTick();
+    Assert.equal(
+      toggleCheckbox.checked,
+      afterToggleClick1.toggleChecked,
+      `After 2nd click, expect toggle to be checked? ${afterToggleClick0.toggleChecked}, actual: ${toggleCheckbox.checked}`
+    );
+    Assert.equal(
+      passwordTextbox.type,
+      afterToggleClick1.inputType,
+      `After 2nd click, expect password input to have type: ${afterToggleClick1.inputType}`
+    );
+  }
+}
+
+async function initForm(browser, formDefaults) {
+  await ContentTask.spawn(
+    browser,
+    formDefaults,
+    async function (selectorValues = {}) {
+      for (let [sel, value] of Object.entries(selectorValues)) {
+        content.document.querySelector(sel).value = value;
+      }
+    }
+  );
+}
+
+async function checkForm(browser, expected) {
+  await ContentTask.spawn(
+    browser,
+    {
+      [passwordInputSelector]: expected.password,
+      [usernameInputSelector]: expected.username,
+    },
+    async function contentCheckForm(selectorValues) {
+      for (let [sel, value] of Object.entries(selectorValues)) {
+        let field = content.document.querySelector(sel);
+        Assert.equal(
+          field.value,
+          value,
+          sel + " has the expected initial value"
+        );
+      }
+    }
+  );
+}
+
+async function submitForm(browser, action = "") {
+  // Submit the form
+  let correctPathNamePromise = BrowserTestUtils.browserLoaded(browser);
+  await SpecialPowers.spawn(browser, [action], async function (actionPathname) {
+    let form = content.document.querySelector("form");
+    if (actionPathname) {
+      form.action = actionPathname;
+    }
+    info("Submitting form to:" + form.action);
+    form.submit();
+    info("Submitted the form");
+  });
+  await correctPathNamePromise;
+  await SpecialPowers.spawn(browser, [action], async actionPathname => {
+    let win = content;
+    await ContentTaskUtils.waitForCondition(() => {
+      return (
+        win.location.pathname == actionPathname &&
+        win.document.readyState == "complete"
+      );
+    }, "Wait for form submission load");
+  });
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_username_edits.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_username_edits.js
new file mode 100644
index 0000000000..79dd92db12
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_username_edits.js
@@ -0,0 +1,192 @@
+/**
+ * Test changing the username inside the doorhanger notification for passwords.
+ *
+ * We have to test combination of existing and non-existing logins both for
+ * the original one from the webpage and the final one used by the dialog.
+ *
+ * We also check switching to and from empty usernames.
+ */
+add_task(async function test_edit_username() {
+  let testCases = [
+    {
+      usernameInPage: "username",
+      usernameChangedTo: "newUsername",
+    },
+    {
+      usernameInPage: "username",
+      usernameInPageExists: true,
+      usernameChangedTo: "newUsername",
+    },
+    {
+      usernameInPage: "username",
+      usernameChangedTo: "newUsername",
+      usernameChangedToExists: true,
+    },
+    {
+      usernameInPage: "username",
+      usernameInPageExists: true,
+      usernameChangedTo: "newUsername",
+      usernameChangedToExists: true,
+    },
+    {
+      usernameInPage: "",
+      usernameChangedTo: "newUsername",
+    },
+    {
+      usernameInPage: "newUsername",
+      usernameChangedTo: "",
+    },
+    {
+      usernameInPage: "",
+      usernameChangedTo: "newUsername",
+      usernameChangedToExists: true,
+    },
+    {
+      usernameInPage: "newUsername",
+      usernameChangedTo: "",
+      usernameChangedToExists: true,
+    },
+  ];
+
+  for (let testCase of testCases) {
+    info("Test case: " + JSON.stringify(testCase));
+    // Clean state before the test case is executed.
+    await LoginTestUtils.clearData();
+    await cleanupDoorhanger();
+    await cleanupPasswordNotifications();
+
+    // Create the pre-existing logins when needed.
+    if (testCase.usernameInPageExists) {
+      await Services.logins.addLoginAsync(
+        LoginTestUtils.testData.formLogin({
+          origin: "https://example.com",
+          formActionOrigin: "https://example.com",
+          username: testCase.usernameInPage,
+          password: "old password",
+        })
+      );
+    }
+
+    if (testCase.usernameChangedToExists) {
+      await Services.logins.addLoginAsync(
+        LoginTestUtils.testData.formLogin({
+          origin: "https://example.com",
+          formActionOrigin: "https://example.com",
+          username: testCase.usernameChangedTo,
+          password: "old password",
+        })
+      );
+    }
+
+    let formFilledPromise = listenForTestNotification("FormProcessed");
+
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url:
+          "https://example.com/browser/toolkit/components/" +
+          "passwordmgr/test/browser/form_basic.html",
+      },
+      async function (browser) {
+        await formFilledPromise;
+        await initForm(browser, {
+          "#form-basic-username": testCase.usernameInPage,
+        });
+
+        let passwordEditedPromise = listenForTestNotification(
+          "PasswordEditedOrGenerated"
+        );
+        info("Editing the form");
+        await changeContentFormValues(browser, {
+          "#form-basic-password": "password",
+        });
+        info("Waiting for passwordEditedPromise");
+        await passwordEditedPromise;
+
+        // reset doorhanger/notifications, we're only interested in the submit outcome
+        await cleanupDoorhanger();
+        await cleanupPasswordNotifications();
+        // reset message cache, we're only interested in the submit outcome
+        await clearMessageCache(browser);
+
+        // Submit the form in the content page with the credentials from the test
+        // case. This will cause the doorhanger notification to be displayed.
+        info("Submitting the form");
+        let formSubmittedPromise = listenForTestNotification("ShowDoorhanger");
+        let promiseShown = BrowserTestUtils.waitForEvent(
+          PopupNotifications.panel,
+          "popupshown",
+          event => event.target == PopupNotifications.panel
+        );
+        await SpecialPowers.spawn(browser, [], async function () {
+          content.document.getElementById("form-basic").submit();
+        });
+        info("Waiting for the submit message");
+        await formSubmittedPromise;
+
+        info("Waiting for the doorhanger");
+        let notif = await waitForDoorhanger(browser, "any");
+        Assert.ok(!notif.dismissed, "Doorhanger is not dismissed");
+        await promiseShown;
+
+        // Modify the username in the dialog if requested.
+        if (testCase.usernameChangedTo !== undefined) {
+          await updateDoorhangerInputValues({
+            username: testCase.usernameChangedTo,
+          });
+        }
+
+        // We expect a modifyLogin notification if the final username used by the
+        // dialog exists in the logins database, otherwise an addLogin one.
+        let expectModifyLogin =
+          testCase.usernameChangedTo !== undefined
+            ? testCase.usernameChangedToExists
+            : testCase.usernameInPageExists;
+        // Simulate the action on the notification to request the login to be
+        // saved, and wait for the data to be updated or saved based on the type
+        // of operation we expect.
+        let expectedNotification = expectModifyLogin
+          ? "modifyLogin"
+          : "addLogin";
+        let promiseLogin = TestUtils.topicObserved(
+          "passwordmgr-storage-changed",
+          (_, data) => data == expectedNotification
+        );
+        let promiseHidden = BrowserTestUtils.waitForEvent(
+          PopupNotifications.panel,
+          "popuphidden"
+        );
+        clickDoorhangerButton(notif, CHANGE_BUTTON);
+        await promiseHidden;
+        info("Waiting for storage changed");
+        let [result] = await promiseLogin;
+
+        // Check that the values in the database match the expected values.
+        let login = expectModifyLogin
+          ? result
+              .QueryInterface(Ci.nsIArray)
+              .queryElementAt(1, Ci.nsILoginInfo)
+          : result.QueryInterface(Ci.nsILoginInfo);
+        Assert.equal(
+          login.username,
+          testCase.usernameChangedTo !== undefined
+            ? testCase.usernameChangedTo
+            : testCase.usernameInPage
+        );
+        Assert.equal(login.password, "password");
+      }
+    );
+  }
+});
+
+async function initForm(browser, formDefaults = {}) {
+  await ContentTask.spawn(
+    browser,
+    formDefaults,
+    async function (selectorValues) {
+      for (let [sel, value] of Object.entries(selectorValues)) {
+        content.document.querySelector(sel).value = value;
+      }
+    }
+  );
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_doorhanger_window_open.js b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_window_open.js
new file mode 100644
index 0000000000..ea0437955d
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_doorhanger_window_open.js
@@ -0,0 +1,201 @@
+/*
+ * Test capture popup notifications in content opened by window.open
+ */
+
+let nsLoginInfo = new Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  Ci.nsILoginInfo,
+  "init"
+);
+let login1 = new nsLoginInfo(
+  "http://mochi.test:8888",
+  "http://mochi.test:8888",
+  null,
+  "notifyu1",
+  "notifyp1",
+  "user",
+  "pass"
+);
+let login2 = new nsLoginInfo(
+  "http://mochi.test:8888",
+  "http://mochi.test:8888",
+  null,
+  "notifyu2",
+  "notifyp2",
+  "user",
+  "pass"
+);
+
+function withTestTabUntilStorageChange(aPageFile, aTaskFn) {
+  function storageChangedObserved(subject, data) {
+    // Watch for actions triggered from a doorhanger (not cleanup tasks with removeLogin)
+    if (data == "removeLogin") {
+      return false;
+    }
+    return true;
+  }
+
+  let storageChangedPromised = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    storageChangedObserved
+  );
+  return BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "http://mochi.test:8888" + DIRECTORY_PATH + aPageFile,
+    },
+    async function (browser) {
+      Assert.ok(true, "loaded " + aPageFile);
+      info("running test case task");
+      await aTaskFn();
+      info("waiting for storage change");
+      await storageChangedPromised;
+    }
+  );
+}
+
+add_setup(async function () {
+  await SimpleTest.promiseFocus(window);
+});
+
+add_task(async function test_saveChromeHiddenAutoClose() {
+  let notifShownPromise = BrowserTestUtils.waitForEvent(
+    PopupNotifications.panel,
+    "popupshown"
+  );
+  // query arguments are: username, password, features, auto-close (delimited by '|')
+  let url =
+    "subtst_notifications_11.html?notifyu1|notifyp1|" +
+    "menubar=no,toolbar=no,location=no|autoclose";
+  await withTestTabUntilStorageChange(url, async function () {
+    info("waiting for popupshown");
+    await notifShownPromise;
+    // the popup closes and the doorhanger should appear in the opener
+    let popup = await getCaptureDoorhangerThatMayOpen("password-save");
+    Assert.ok(popup, "got notification popup");
+    await checkDoorhangerUsernamePassword("notifyu1", "notifyp1");
+    // Sanity check, no logins should exist yet.
+    let logins = await Services.logins.getAllLogins();
+    Assert.equal(logins.length, 0, "Should not have any logins yet");
+
+    clickDoorhangerButton(popup, REMEMBER_BUTTON);
+  });
+  // Check result of clicking Remember
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.timesUsed, 1, "Check times used on new entry");
+  Assert.equal(
+    login.username,
+    "notifyu1",
+    "Check the username used on the new entry"
+  );
+  Assert.equal(
+    login.password,
+    "notifyp1",
+    "Check the password used on the new entry"
+  );
+});
+
+add_task(async function test_changeChromeHiddenAutoClose() {
+  let notifShownPromise = BrowserTestUtils.waitForEvent(
+    PopupNotifications.panel,
+    "popupshown"
+  );
+  let url =
+    "subtst_notifications_11.html?notifyu1|pass2|menubar=no,toolbar=no,location=no|autoclose";
+  await withTestTabUntilStorageChange(url, async function () {
+    info("waiting for popupshown");
+    await notifShownPromise;
+    let popup = await getCaptureDoorhangerThatMayOpen("password-change");
+    Assert.ok(popup, "got notification popup");
+    await checkDoorhangerUsernamePassword("notifyu1", "pass2");
+    clickDoorhangerButton(popup, CHANGE_BUTTON);
+  });
+
+  // Check to make sure we updated the password, timestamps and use count for
+  // the login being changed with this form.
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username");
+  Assert.equal(login.password, "pass2", "Check password changed");
+  Assert.equal(login.timesUsed, 2, "check .timesUsed incremented on change");
+  Assert.ok(login.timeCreated < login.timeLastUsed, "timeLastUsed bumped");
+  Assert.ok(
+    login.timeLastUsed == login.timePasswordChanged,
+    "timeUsed == timeChanged"
+  );
+
+  login1.password = "pass2";
+  Services.logins.removeLogin(login1);
+  login1.password = "notifyp1";
+});
+
+add_task(async function test_saveChromeVisibleSameWindow() {
+  // This test actually opens a new tab in the same window with default browser settings.
+  let url = "subtst_notifications_11.html?notifyu2|notifyp2||";
+  let notifShownPromise = BrowserTestUtils.waitForEvent(
+    PopupNotifications.panel,
+    "popupshown"
+  );
+  await withTestTabUntilStorageChange(url, async function () {
+    await notifShownPromise;
+    let popup = await getCaptureDoorhangerThatMayOpen("password-save");
+    Assert.ok(popup, "got notification popup");
+    await checkDoorhangerUsernamePassword("notifyu2", "notifyp2");
+    clickDoorhangerButton(popup, REMEMBER_BUTTON);
+    BrowserTestUtils.removeTab(gBrowser.selectedTab);
+  });
+
+  // Check result of clicking Remember
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login now");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(
+    login.username,
+    "notifyu2",
+    "Check the username used on the new entry"
+  );
+  Assert.equal(
+    login.password,
+    "notifyp2",
+    "Check the password used on the new entry"
+  );
+  Assert.equal(login.timesUsed, 1, "Check times used on new entry");
+});
+
+add_task(async function test_changeChromeVisibleSameWindow() {
+  let url = "subtst_notifications_11.html?notifyu2|pass2||";
+  let notifShownPromise = BrowserTestUtils.waitForEvent(
+    PopupNotifications.panel,
+    "popupshown"
+  );
+  await withTestTabUntilStorageChange(url, async function () {
+    await notifShownPromise;
+    let popup = await getCaptureDoorhangerThatMayOpen("password-change");
+    Assert.ok(popup, "got notification popup");
+    await checkDoorhangerUsernamePassword("notifyu2", "pass2");
+    clickDoorhangerButton(popup, CHANGE_BUTTON);
+    BrowserTestUtils.removeTab(gBrowser.selectedTab);
+  });
+
+  // Check to make sure we updated the password, timestamps and use count for
+  // the login being changed with this form.
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should have 1 login");
+  let login = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu2", "Check the username");
+  Assert.equal(login.password, "pass2", "Check password changed");
+  Assert.equal(login.timesUsed, 2, "check .timesUsed incremented on change");
+  Assert.ok(login.timeCreated < login.timeLastUsed, "timeLastUsed bumped");
+  Assert.ok(
+    login.timeLastUsed == login.timePasswordChanged,
+    "timeUsed == timeChanged"
+  );
+
+  // cleanup
+  login2.password = "pass2";
+  Services.logins.removeLogin(login2);
+  login2.password = "notifyp2";
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_entry_point_telemetry.js b/toolkit/components/passwordmgr/test/browser/browser_entry_point_telemetry.js
new file mode 100644
index 0000000000..e400dc4637
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_entry_point_telemetry.js
@@ -0,0 +1,103 @@
+const TEST_ORIGIN = "https://example.com";
+
+add_setup(async function () {
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.rememberSignons.visibilityToggle", true]],
+  });
+  Services.telemetry.clearEvents();
+});
+
+add_task(async function mainMenu_entryPoint() {
+  await SimpleTest.promiseFocus();
+  info("mainMenu_entryPoint, got focus");
+
+  let mainMenu = document.getElementById("appMenu-popup");
+  let target = document.getElementById("PanelUI-menu-button");
+  await TestUtils.waitForCondition(
+    () => BrowserTestUtils.isVisible(target),
+    "Main menu button should be visible."
+  );
+  info("mainMenu_entryPoint, Main menu button is visible");
+  Assert.equal(
+    mainMenu.state,
+    "closed",
+    `Menu panel (${mainMenu.id}) is initally closed.`
+  );
+
+  info("mainMenu_entryPoint, clicking target and waiting for popup");
+  let popupshown = BrowserTestUtils.waitForEvent(mainMenu, "popupshown");
+  EventUtils.synthesizeMouseAtCenter(target, {});
+  await popupshown;
+
+  info("mainMenu_entryPoint, main menu popup is shown");
+  Assert.equal(mainMenu.state, "open", `Menu panel (${mainMenu.id}) is open.`);
+
+  let loginsButtonID = "appMenu-passwords-button";
+
+  let item = document.getElementById(loginsButtonID);
+  await TestUtils.waitForCondition(
+    () => BrowserTestUtils.isVisible(item),
+    "Logins and passwords button is visible."
+  );
+
+  info("mainMenu_entryPoint, clicking on Logins and passwords button");
+  let openingFunc = () => EventUtils.synthesizeMouseAtCenter(item, {});
+  let passwordManager = await openPasswordManager(openingFunc);
+  info("mainMenu_entryPoint, password manager dialog shown");
+
+  await LoginTestUtils.telemetry.waitForEventCount(1);
+  TelemetryTestUtils.assertEvents(
+    [["pwmgr", "open_management", "mainmenu"]],
+    {
+      category: "pwmgr",
+      method: "open_management",
+    },
+    { clear: true, process: "content" }
+  );
+
+  info("mainMenu_entryPoint, close dialog and main menu");
+  await passwordManager.close();
+  mainMenu.hidePopup();
+});
+
+add_task(async function pageInfo_entryPoint() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_ORIGIN,
+    },
+    async function (browser) {
+      info("pageInfo_entryPoint, opening pageinfo");
+      let pageInfo = BrowserPageInfo(TEST_ORIGIN, "securityTab", {});
+      await BrowserTestUtils.waitForEvent(pageInfo, "page-info-init");
+      info(
+        "pageInfo_entryPoint, got pageinfo, wait until password button is visible"
+      );
+      let passwordsButton = pageInfo.document.getElementById(
+        "security-view-password"
+      );
+
+      await TestUtils.waitForCondition(
+        () => BrowserTestUtils.isVisible(passwordsButton),
+        "Show passwords button should be visible."
+      );
+      info("pageInfo_entryPoint, clicking the show passwords button...");
+      await SimpleTest.promiseFocus(pageInfo);
+      let openingFunc = () =>
+        EventUtils.synthesizeMouseAtCenter(passwordsButton, {}, pageInfo);
+
+      info("pageInfo_entryPoint, waiting for the passwords manager dialog");
+      let passwordManager = await openPasswordManager(openingFunc);
+
+      TelemetryTestUtils.assertEvents(
+        [["pwmgr", "open_management", "pageinfo"]],
+        { category: "pwmgr", method: "open_management" },
+        { clear: true, process: "content" }
+      );
+
+      info("pageInfo_entryPoint, close dialog and pageInfo");
+      await passwordManager.close();
+      pageInfo.close();
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_exceptions_dialog.js b/toolkit/components/passwordmgr/test/browser/browser_exceptions_dialog.js
new file mode 100644
index 0000000000..854f0656b8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_exceptions_dialog.js
@@ -0,0 +1,141 @@
+"use strict";
+
+const LOGIN_HOST = "https://example.com";
+
+function openExceptionsDialog() {
+  return window.openDialog(
+    "chrome://browser/content/preferences/dialogs/permissions.xhtml",
+    "Toolkit:PasswordManagerExceptions",
+    "",
+    {
+      blockVisible: true,
+      sessionVisible: false,
+      allowVisible: false,
+      hideStatusColumn: true,
+      prefilledHost: "",
+      permissionType: "login-saving",
+    }
+  );
+}
+
+function countDisabledHosts(dialog) {
+  return dialog.document.getElementById("permissionsBox").itemCount;
+}
+
+function promiseStorageChanged(expectedData) {
+  function observer(subject, data) {
+    return (
+      data == expectedData &&
+      subject.QueryInterface(Ci.nsISupportsString).data == LOGIN_HOST
+    );
+  }
+
+  return TestUtils.topicObserved("passwordmgr-storage-changed", observer);
+}
+
+add_task(async function test_disable() {
+  let dialog = openExceptionsDialog();
+  let promiseChanged = promiseStorageChanged("hostSavingDisabled");
+
+  await BrowserTestUtils.waitForEvent(dialog, "load");
+  await new Promise(resolve => {
+    waitForFocus(resolve, dialog);
+  });
+  Services.logins.setLoginSavingEnabled(LOGIN_HOST, false);
+  await promiseChanged;
+  Assert.equal(countDisabledHosts(dialog), 1, "Verify disabled host added");
+  await BrowserTestUtils.closeWindow(dialog);
+});
+
+add_task(async function test_enable() {
+  let dialog = openExceptionsDialog();
+  let promiseChanged = promiseStorageChanged("hostSavingEnabled");
+
+  await BrowserTestUtils.waitForEvent(dialog, "load");
+  await new Promise(resolve => {
+    waitForFocus(resolve, dialog);
+  });
+  Services.logins.setLoginSavingEnabled(LOGIN_HOST, true);
+  await promiseChanged;
+  Assert.equal(countDisabledHosts(dialog), 0, "Verify disabled host removed");
+  await BrowserTestUtils.closeWindow(dialog);
+});
+
+add_task(async function test_block_button_with_enter_key() {
+  // Test ensures that the Enter/Return key does not activate the "Allow" button
+  // in the "Saved Logins" exceptions dialog
+
+  let dialog = openExceptionsDialog();
+
+  await BrowserTestUtils.waitForEvent(dialog, "load");
+  await new Promise(resolve => waitForFocus(resolve, dialog));
+  let btnBlock = dialog.document.getElementById("btnBlock");
+  let btnCookieSession = dialog.document.getElementById("btnCookieSession");
+  let btnHttpsOnlyOff = dialog.document.getElementById("btnHttpsOnlyOff");
+  let btnHttpsOnlyOffTmp = dialog.document.getElementById("btnHttpsOnlyOffTmp");
+  let btnAllow = dialog.document.getElementById("btnAllow");
+
+  Assert.ok(!btnBlock.hidden, "Block button is visible");
+  Assert.ok(btnCookieSession.hidden, "Cookie session button is not visible");
+  Assert.ok(btnAllow.hidden, "Allow button is not visible");
+  Assert.ok(btnHttpsOnlyOff.hidden, "HTTPS-Only session button is not visible");
+  Assert.ok(
+    btnHttpsOnlyOffTmp.hidden,
+    "HTTPS-Only session button is not visible"
+  );
+  Assert.ok(btnBlock.disabled, "Block button is initially disabled");
+  Assert.ok(
+    btnCookieSession.disabled,
+    "Cookie session button is initially disabled"
+  );
+  Assert.ok(btnAllow.disabled, "Allow button is initially disabled");
+  Assert.ok(
+    btnHttpsOnlyOff.disabled,
+    "HTTPS-Only off-button is initially disabled"
+  );
+  Assert.ok(
+    btnHttpsOnlyOffTmp.disabled,
+    "HTTPS-Only temporary off-button is initially disabled"
+  );
+
+  EventUtils.sendString(LOGIN_HOST, dialog);
+
+  Assert.ok(
+    !btnBlock.disabled,
+    "Block button is enabled after entering text in the URL input"
+  );
+  Assert.ok(
+    btnCookieSession.disabled,
+    "Cookie session button is still disabled after entering text in the URL input"
+  );
+  Assert.ok(
+    btnAllow.disabled,
+    "Allow button is still disabled after entering text in the URL input"
+  );
+  Assert.ok(
+    btnHttpsOnlyOff.disabled,
+    "HTTPS-Only off-button is still disabled after entering text in the URL input"
+  );
+  Assert.ok(
+    btnHttpsOnlyOffTmp.disabled,
+    "HTTPS-Only session off-button is still disabled after entering text in the URL input"
+  );
+
+  Assert.equal(
+    countDisabledHosts(dialog),
+    0,
+    "No blocked hosts should be present before hitting the Enter/Return key"
+  );
+  EventUtils.sendKey("return", dialog);
+
+  Assert.equal(
+    countDisabledHosts(dialog),
+    1,
+    "Verify the blocked host was added"
+  );
+  Assert.ok(
+    btnBlock.disabled,
+    "Block button is disabled after submitting to the list"
+  );
+  await BrowserTestUtils.closeWindow(dialog);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_fileURIOrigin.js b/toolkit/components/passwordmgr/test/browser/browser_fileURIOrigin.js
new file mode 100644
index 0000000000..ae8c860792
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_fileURIOrigin.js
@@ -0,0 +1,51 @@
+/* Any copyright is dedicated to the Public Domain.
+ * https://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+function getDataFromNextSubmitMessage() {
+  return new Promise(resolve => {
+    LoginManagerParent.setListenerForTests((msg, data) => {
+      if (msg == "ShowDoorhanger") {
+        resolve(data);
+      }
+    });
+  });
+}
+
+add_task(async function testCrossOriginFormUsesCorrectOrigin() {
+  const registry = Cc["@mozilla.org/chrome/chrome-registry;1"].getService(
+    Ci.nsIChromeRegistry
+  );
+
+  let dataPromise = getDataFromNextSubmitMessage();
+
+  let url =
+    registry.convertChromeURL(Services.io.newURI(getRootDirectory(gTestPath)))
+      .asciiSpec + "form_basic.html";
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function (browser) {
+      await SpecialPowers.spawn(browser.browsingContext, [], () => {
+        let doc = content.document;
+        doc.getElementById("form-basic-username").setUserInput("username");
+        doc.getElementById("form-basic-password").setUserInput("password");
+        doc.getElementById("form-basic").submit();
+        info("Submitting form");
+      });
+    }
+  );
+
+  let data = await dataPromise;
+  info("Origin retrieved from message listener");
+
+  Assert.equal(
+    data.origin,
+    "file://",
+    "Message origin should match form origin"
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_focus_before_first_DOMContentLoaded.js b/toolkit/components/passwordmgr/test/browser/browser_focus_before_first_DOMContentLoaded.js
new file mode 100644
index 0000000000..783f8ea3d8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_focus_before_first_DOMContentLoaded.js
@@ -0,0 +1,103 @@
+/**
+ * Test that autocomplete is properly attached to a username field which gets
+ * focused before DOMContentLoaded in a new browser and process.
+ */
+
+"use strict";
+
+add_setup(async () => {
+  let nsLoginInfo = Components.Constructor(
+    "@mozilla.org/login-manager/loginInfo;1",
+    Ci.nsILoginInfo,
+    "init"
+  );
+  Assert.ok(nsLoginInfo != null, "nsLoginInfo constructor");
+
+  info("Adding two logins to get autocomplete instead of autofill");
+  let login1 = new nsLoginInfo(
+    "https://example.com",
+    "https://autocomplete:8888",
+    null,
+    "tempuser1",
+    "temppass1"
+  );
+
+  let login2 = new nsLoginInfo(
+    "https://example.com",
+    "https://autocomplete:8888",
+    null,
+    "testuser2",
+    "testpass2"
+  );
+
+  await Services.logins.addLogins([login1, login2]);
+});
+
+add_task(async function test_autocompleteFromUsername() {
+  let autocompletePopup = document.getElementById("PopupAutoComplete");
+  let autocompletePopupShown = BrowserTestUtils.waitForEvent(
+    autocompletePopup,
+    "popupshown"
+  );
+
+  const URL = `https://example.com${DIRECTORY_PATH}file_focus_before_DOMContentLoaded.sjs`;
+
+  let newTab = await BrowserTestUtils.openNewForegroundTab({
+    gBrowser,
+    opening: URL,
+    forceNewProcess: true,
+  });
+
+  await SpecialPowers.spawn(
+    newTab.linkedBrowser,
+    [],
+    function checkInitialValues() {
+      let doc = content.document;
+      let uname = doc.querySelector("#uname");
+      let pword = doc.querySelector("#pword");
+
+      Assert.ok(uname, "Username field found");
+      Assert.ok(pword, "Password field found");
+
+      Assert.equal(
+        doc.activeElement,
+        uname,
+        "#uname element should be focused"
+      );
+      Assert.equal(uname.value, "", "Checking username is empty");
+      Assert.equal(pword.value, "", "Checking password is empty");
+    }
+  );
+
+  await BrowserTestUtils.synthesizeKey("VK_DOWN", {}, newTab.linkedBrowser);
+  await autocompletePopupShown;
+
+  let richlistbox = autocompletePopup.richlistbox;
+  Assert.equal(
+    richlistbox.localName,
+    "richlistbox",
+    "The richlistbox should be the first anonymous node"
+  );
+  for (let i = 0; i < autocompletePopup.view.matchCount; i++) {
+    if (
+      richlistbox.selectedItem &&
+      richlistbox.selectedItem.textContent.includes("tempuser1")
+    ) {
+      break;
+    }
+    await BrowserTestUtils.synthesizeKey("VK_DOWN", {}, newTab.linkedBrowser);
+  }
+
+  await BrowserTestUtils.synthesizeKey("VK_RETURN", {}, newTab.linkedBrowser);
+
+  await SpecialPowers.spawn(newTab.linkedBrowser, [], function checkFill() {
+    let doc = content.document;
+    let uname = doc.querySelector("#uname");
+    let pword = doc.querySelector("#pword");
+
+    Assert.equal(uname.value, "tempuser1", "Checking username is filled");
+    Assert.equal(pword.value, "temppass1", "Checking password is filled");
+  });
+
+  BrowserTestUtils.removeTab(newTab);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_form_history_fallback.js b/toolkit/components/passwordmgr/test/browser/browser_form_history_fallback.js
new file mode 100644
index 0000000000..6a198e021a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_form_history_fallback.js
@@ -0,0 +1,72 @@
+const { FormHistoryTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/FormHistoryTestUtils.sys.mjs"
+);
+
+const usernameFieldName = "user";
+
+async function cleanup() {
+  Services.prefs.clearUserPref("signon.rememberSignons");
+  Services.logins.removeAllLogins();
+  await FormHistoryTestUtils.clear(usernameFieldName);
+}
+
+add_setup(async function () {
+  await cleanup();
+});
+
+add_task(
+  async function test_username_not_saved_in_form_history_when_password_manager_enabled() {
+    Services.prefs.setBoolPref("signon.rememberSignons", true);
+
+    const storageChangedPromise = TestUtils.topicObserved(
+      "passwordmgr-storage-changed",
+      (_, data) => data == "addLogin"
+    );
+
+    await testSubmittingLoginFormHTTP(
+      "subtst_notifications_1.html",
+      async () => {
+        const notif = await getCaptureDoorhangerThatMayOpen("password-save");
+        await clickDoorhangerButton(notif, REMEMBER_BUTTON);
+      }
+    );
+
+    await storageChangedPromise;
+
+    const loginEntries = (await Services.logins.getAllLogins()).length;
+    const historyEntries = await FormHistoryTestUtils.count(usernameFieldName);
+
+    Assert.equal(
+      loginEntries,
+      1,
+      "Username should be saved in password manager"
+    );
+
+    Assert.equal(
+      historyEntries,
+      0,
+      "Username should not be saved in form history"
+    );
+    await cleanup();
+  }
+);
+
+add_task(
+  async function test_username_saved_in_form_history_when_password_manager_disabled() {
+    Services.prefs.setBoolPref("signon.rememberSignons", false);
+
+    await testSubmittingLoginFormHTTP("subtst_notifications_1.html");
+
+    const loginEntries = (await Services.logins.getAllLogins()).length;
+    const historyEntries = await FormHistoryTestUtils.count(usernameFieldName);
+
+    Assert.equal(
+      loginEntries,
+      0,
+      "Username should not be saved in password manager"
+    );
+
+    Assert.equal(historyEntries, 1, "Username should be saved in form history");
+    await cleanup();
+  }
+);
diff --git a/toolkit/components/passwordmgr/test/browser/browser_formless_submit_chrome.js b/toolkit/components/passwordmgr/test/browser/browser_formless_submit_chrome.js
new file mode 100644
index 0000000000..bb7e973db6
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_formless_submit_chrome.js
@@ -0,0 +1,161 @@
+/*
+ * Test that browser chrome UI interactions don't trigger a capture doorhanger.
+ */
+
+"use strict";
+
+async function fillTestPage(
+  aBrowser,
+  username = "my_username",
+  password = "my_password"
+) {
+  let notif = getCaptureDoorhanger("any", undefined, aBrowser);
+  Assert.ok(!notif, "No doorhangers should be present before filling the form");
+
+  await changeContentFormValues(aBrowser, {
+    "#form-basic-username": username,
+    "#form-basic-password": password,
+  });
+  if (LoginHelper.passwordEditCaptureEnabled) {
+    // Filling the password will generate a dismissed doorhanger.
+    // Check and remove that before running the rest of the task
+    notif = await waitForDoorhanger(aBrowser, "any");
+    Assert.ok(notif.dismissed, "Only a dismissed doorhanger should be present");
+    await cleanupDoorhanger(notif);
+  }
+}
+
+function withTestPage(aTaskFn) {
+  return BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "https://example.com" + DIRECTORY_PATH + "formless_basic.html",
+    },
+    async function (aBrowser) {
+      info("tab opened");
+      await fillTestPage(aBrowser);
+      await aTaskFn(aBrowser);
+
+      // Give a chance for the doorhanger to appear
+      await new Promise(resolve => SimpleTest.executeSoon(resolve));
+      let notif = getCaptureDoorhanger("any");
+      Assert.ok(!notif, "No doorhanger should be present");
+      await cleanupDoorhanger(notif);
+    }
+  );
+}
+
+add_setup(async function () {
+  await SimpleTest.promiseFocus(window);
+});
+
+add_task(async function test_urlbar_new_URL() {
+  await withTestPage(async function (aBrowser) {
+    gURLBar.value = "";
+    let focusPromise = BrowserTestUtils.waitForEvent(gURLBar, "focus");
+    gURLBar.focus();
+    await focusPromise;
+    info("focused");
+    EventUtils.sendString("http://mochi.test:8888/");
+    EventUtils.synthesizeKey("KEY_Enter");
+    await BrowserTestUtils.browserLoaded(
+      aBrowser,
+      false,
+      "http://mochi.test:8888/"
+    );
+  });
+});
+
+add_task(async function test_urlbar_fragment_enter() {
+  await withTestPage(function (aBrowser) {
+    gURLBar.focus();
+    gURLBar.select();
+    EventUtils.synthesizeKey("KEY_ArrowRight");
+    EventUtils.sendString("#fragment");
+    EventUtils.synthesizeKey("KEY_Enter");
+  });
+});
+
+add_task(async function test_backButton_forwardButton() {
+  await withTestPage(async function (aBrowser) {
+    info("Loading formless_basic.html?second");
+    // Load a new page in the tab so we can test going back
+    BrowserTestUtils.startLoadingURIString(
+      aBrowser,
+      "https://example.com" + DIRECTORY_PATH + "formless_basic.html?second"
+    );
+    await BrowserTestUtils.browserLoaded(
+      aBrowser,
+      false,
+      "https://example.com" + DIRECTORY_PATH + "formless_basic.html?second"
+    );
+    info("Loaded formless_basic.html?second");
+    await fillTestPage(aBrowser, "my_username", "password_2");
+
+    info("formless_basic.html?second form is filled, clicking back");
+    let backPromise = BrowserTestUtils.browserStopped(aBrowser);
+    EventUtils.synthesizeMouseAtCenter(
+      document.getElementById("back-button"),
+      {}
+    );
+    await backPromise;
+
+    // Give a chance for the doorhanger to appear
+    await new Promise(resolve => SimpleTest.executeSoon(resolve));
+    Assert.ok(!getCaptureDoorhanger("any"), "No doorhanger should be present");
+
+    // Now go forward again after filling
+    await fillTestPage(aBrowser, "my_username", "password_3");
+
+    let forwardButton = document.getElementById("forward-button");
+    await BrowserTestUtils.waitForCondition(() => {
+      return !forwardButton.disabled;
+    });
+    let forwardPromise = BrowserTestUtils.browserStopped(aBrowser);
+    info("click the forward button");
+    EventUtils.synthesizeMouseAtCenter(forwardButton, {});
+    await forwardPromise;
+    info("done");
+  });
+});
+
+add_task(async function test_reloadButton() {
+  await withTestPage(async function (aBrowser) {
+    let reloadButton = document.getElementById("reload-button");
+    let loadPromise = BrowserTestUtils.browserLoaded(
+      aBrowser,
+      false,
+      "https://example.com" + DIRECTORY_PATH + "formless_basic.html"
+    );
+
+    await BrowserTestUtils.waitForCondition(() => {
+      return !reloadButton.disabled;
+    });
+    EventUtils.synthesizeMouseAtCenter(reloadButton, {});
+    await loadPromise;
+  });
+});
+
+add_task(async function test_back_keyboard_shortcut() {
+  await withTestPage(async function (aBrowser) {
+    // Load a new page in the tab so we can test going back
+    BrowserTestUtils.startLoadingURIString(
+      aBrowser,
+      "https://example.com" + DIRECTORY_PATH + "formless_basic.html?second"
+    );
+    await BrowserTestUtils.browserLoaded(
+      aBrowser,
+      false,
+      "https://example.com" + DIRECTORY_PATH + "formless_basic.html?second"
+    );
+    await fillTestPage(aBrowser);
+
+    let backPromise = BrowserTestUtils.browserStopped(aBrowser);
+
+    const goBackKeyModifier =
+      AppConstants.platform == "macosx" ? { metaKey: true } : { altKey: true };
+    EventUtils.synthesizeKey("KEY_ArrowLeft", goBackKeyModifier);
+
+    await backPromise;
+  });
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_glean_pwmgr_form_autofill_result.js b/toolkit/components/passwordmgr/test/browser/browser_glean_pwmgr_form_autofill_result.js
new file mode 100644
index 0000000000..41ca5c85e9
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_glean_pwmgr_form_autofill_result.js
@@ -0,0 +1,186 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativ.orgmons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Testing every label of the labeled counter pwmgr.form_autofill_result (Glean metric)
+ */
+
+"use strict";
+
+const { AUTOFILL_RESULT } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerChild.sys.mjs"
+);
+const gAutofillLabels = Object.values(AUTOFILL_RESULT);
+
+const gLogin = LoginTestUtils.testData.formLogin({
+  origin: "https://example.org",
+  formActionOrigin: "https://example.org/",
+  username: "username1",
+  password: "password1",
+});
+const gMultipleLogin = LoginTestUtils.testData.formLogin({
+  origin: "https://example.org",
+  formActionOrigin: "https://example.org/",
+  username: "username2",
+  password: "password2",
+});
+const gLoginInsecureAction = LoginTestUtils.testData.formLogin({
+  origin: "https://example.org",
+  // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+  formActionOrigin: "http://example.org/",
+  username: "username3",
+  password: "password3",
+});
+
+const TEST_CASES = [
+  {
+    description: "Autofill result - filled",
+    autofill_result: "filled",
+    test_url: `https://example.org${DIRECTORY_PATH}form_basic_login.html`,
+  },
+  {
+    description: "Autofill result - no_password_field",
+    autofill_result: "no_password_field",
+    test_url: `https://example.org${DIRECTORY_PATH}form_multiple_passwords.html`,
+  },
+  {
+    description: "Autofill result - password_disabled_readonly",
+    autofill_result: "password_disabled_readonly",
+    test_url: `https://example.org${DIRECTORY_PATH}form_disabled_readonly_passwordField.html`,
+    form_processed_count: 2,
+    metric_count: 2,
+  },
+  {
+    description: "Autofill results no_logins_fit",
+    autofill_result: "no_logins_fit",
+    test_url: `https://example.org${DIRECTORY_PATH}form_basic_login_fields_with_max_length.html`,
+    metric_count: 2,
+  },
+  {
+    description: "Autofill results - no_saved_logins",
+    autofill_result: "no_saved_logins",
+    test_url: `https://example.com${DIRECTORY_PATH}form_basic_login.html`,
+  },
+  {
+    description: "Autofill results - existing_password",
+    autofill_result: "existing_password",
+    test_url: `https://example.org${DIRECTORY_PATH}form_basic_prefilled_password.html`,
+  },
+  {
+    description: "Autofill results - existing_username",
+    autofill_result: "existing_username",
+    test_url: `https://example.org${DIRECTORY_PATH}form_basic_prefilled_username.html`,
+  },
+  {
+    description: "Autofill results - multiple_logins",
+    autofill_result: "multiple_logins",
+    test_url: `https://example.org${DIRECTORY_PATH}form_basic_login.html`,
+    extra_login: gMultipleLogin,
+  },
+  {
+    description: "Autofill results - no_autofill_forms",
+    autofill_result: "no_autofill_forms",
+    test_url: `https://example.org${DIRECTORY_PATH}form_basic_login.html`,
+    prefs: [["signon.autofillForms", false]],
+  },
+  {
+    description: "Autofill results - autocomplete_off",
+    autofill_result: "autocomplete_off",
+    test_url: `https://example.org${DIRECTORY_PATH}form_basic_password_autocomplete_off.html`,
+    prefs: [["signon.autofillForms.autocompleteOff", false]],
+  },
+  {
+    description: "Autofill results - insecure",
+    autofill_result: "insecure",
+    test_url: `https://example.org${DIRECTORY_PATH}form_cross_origin_insecure_action.html`,
+    extra_login: gLoginInsecureAction,
+  },
+  {
+    description: "Autofill results - password_autocomplete_new_password",
+    autofill_result: "password_autocomplete_new_password",
+    test_url: `https://example.org${DIRECTORY_PATH}form_basic_password_autocomplete_new_password.html`,
+  },
+  {
+    description: "Autofill results - type_no_longer_password",
+    autofill_result: "type_no_longer_password",
+    test_url: `https://example.org${DIRECTORY_PATH}form_unmasked_password_after_pageload.html`,
+  },
+  {
+    description: "Autofill results - form_in_crossorigin_subframe",
+    autofill_result: "form_in_crossorigin_subframe",
+    test_url: `https://example.com${DIRECTORY_PATH}form_crossframe_no_outer_login_form.html`,
+  },
+  {
+    description: "Autofill result - filled_username_only_form",
+    autofill_result: "filled_username_only_form",
+    test_url: `https://example.org${DIRECTORY_PATH}form_username_only.html`,
+  },
+];
+
+add_setup(async () => {
+  await Services.logins.addLoginAsync(gLogin);
+});
+
+async function verifyAutofillResults(testCase) {
+  info(`Test case: ${testCase.description}`);
+
+  if (testCase.prefs) {
+    await SpecialPowers.pushPrefEnv({
+      set: testCase.prefs,
+    });
+  }
+  if (testCase.extra_login) {
+    await Services.logins.addLoginAsync(testCase.extra_login);
+  }
+
+  await Services.fog.testFlushAllChildren();
+  Services.fog.testResetFOG();
+
+  let formProcessed = listenForTestNotification(
+    "FormProcessed",
+    testCase.form_processed_count ?? 1
+  );
+
+  const tab = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    testCase.test_url
+  );
+
+  await formProcessed;
+
+  await Services.fog.testFlushAllChildren();
+
+  gBrowser.removeTab(tab);
+
+  gAutofillLabels.forEach(label => {
+    if (label != testCase.autofill_result) {
+      Assert.equal(
+        undefined,
+        Glean.pwmgr.formAutofillResult[label].testGetValue(),
+        `The counter for the label ${label} was not incremented.`
+      );
+    } else {
+      Assert.equal(
+        testCase.metric_count ?? 1,
+        Glean.pwmgr.formAutofillResult[testCase.autofill_result].testGetValue(),
+        `The counter for the label ${label} was incremented by ${
+          testCase.metric_count ?? 1
+        }.`
+      );
+    }
+  });
+
+  if (testCase.extra_login) {
+    await Services.logins.removeLogin(testCase.extra_login);
+  }
+
+  if (testCase.prefs) {
+    await SpecialPowers.popPrefEnv();
+  }
+}
+
+add_task(async function test_autofill_results() {
+  for (let tc of TEST_CASES) {
+    await verifyAutofillResults(tc);
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_insecurePasswordConsoleWarning.js b/toolkit/components/passwordmgr/test/browser/browser_insecurePasswordConsoleWarning.js
new file mode 100644
index 0000000000..68d5663258
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_insecurePasswordConsoleWarning.js
@@ -0,0 +1,131 @@
+"use strict";
+
+const WARNING_PATTERN = [
+  {
+    key: "INSECURE_FORM_ACTION",
+    msg: 'JavaScript Warning: "Password fields present in a form with an insecure (http://) form action. This is a security risk that allows user login credentials to be stolen."',
+  },
+  {
+    key: "INSECURE_PAGE",
+    msg: 'JavaScript Warning: "Password fields present on an insecure (http://) page. This is a security risk that allows user login credentials to be stolen."',
+  },
+];
+
+add_task(async function testInsecurePasswordWarning() {
+  // By default, proxies don't apply to 127.0.0.1. We need them to for this test, though:
+  await SpecialPowers.pushPrefEnv({
+    set: [["network.proxy.allow_hijacking_localhost", true]],
+  });
+  let warningPatternHandler;
+
+  function messageHandler(msgObj) {
+    function findWarningPattern(msg) {
+      return WARNING_PATTERN.find(patternPair => {
+        return msg.includes(patternPair.msg);
+      });
+    }
+
+    let warning = findWarningPattern(msgObj.message);
+
+    // Only handle the insecure password related warning messages.
+    if (warning) {
+      // Prevent any unexpected or redundant matched warning message coming after
+      // the test case is ended.
+      Assert.ok(
+        warningPatternHandler,
+        "Invoke a valid warning message handler"
+      );
+      warningPatternHandler(warning, msgObj.message);
+    }
+  }
+  Services.console.registerListener(messageHandler);
+  registerCleanupFunction(function () {
+    Services.console.unregisterListener(messageHandler);
+  });
+
+  for (let [origin, testFile, expectWarnings] of [
+    ["http://127.0.0.1", "form_basic.html", []],
+    ["http://127.0.0.1", "formless_basic.html", []],
+    ["http://example.com", "form_basic.html", ["INSECURE_PAGE"]],
+    ["http://example.com", "formless_basic.html", ["INSECURE_PAGE"]],
+    ["https://example.com", "form_basic.html", []],
+    ["https://example.com", "formless_basic.html", []],
+
+    // For a form with customized action link in the same origin.
+    ["http://127.0.0.1", "form_same_origin_action.html", []],
+    ["http://example.com", "form_same_origin_action.html", ["INSECURE_PAGE"]],
+    ["https://example.com", "form_same_origin_action.html", []],
+
+    // For a form with an insecure (http) customized action link.
+    [
+      "http://127.0.0.1",
+      "form_cross_origin_insecure_action.html",
+      ["INSECURE_FORM_ACTION"],
+    ],
+    [
+      "http://example.com",
+      "form_cross_origin_insecure_action.html",
+      ["INSECURE_PAGE"],
+    ],
+    [
+      "https://example.com",
+      "form_cross_origin_insecure_action.html",
+      ["INSECURE_FORM_ACTION"],
+    ],
+
+    // For a form with a secure (https) customized action link.
+    ["http://127.0.0.1", "form_cross_origin_secure_action.html", []],
+    [
+      "http://example.com",
+      "form_cross_origin_secure_action.html",
+      ["INSECURE_PAGE"],
+    ],
+    ["https://example.com", "form_cross_origin_secure_action.html", []],
+  ]) {
+    let testURL = origin + DIRECTORY_PATH + testFile;
+    let promiseConsoleMessages = new Promise(resolve => {
+      warningPatternHandler = function (warning, originMessage) {
+        Assert.ok(warning, "Handling a warning pattern");
+        let fullMessage = `[${warning.msg} {file: "${testURL}" line: 0 column: 0 source: "0"}]`;
+        Assert.equal(
+          originMessage,
+          fullMessage,
+          "Message full matched:" + originMessage
+        );
+
+        let index = expectWarnings.indexOf(warning.key);
+        isnot(
+          index,
+          -1,
+          "Found warning: " + warning.key + " for URL:" + testURL
+        );
+        if (index !== -1) {
+          // Remove the shown message.
+          expectWarnings.splice(index, 1);
+        }
+        if (expectWarnings.length === 0) {
+          info("All warnings are shown for URL:" + testURL);
+          resolve();
+        }
+      };
+    });
+
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url: testURL,
+      },
+      function () {
+        if (expectWarnings.length === 0) {
+          info("All warnings are shown for URL:" + testURL);
+          return Promise.resolve();
+        }
+        return promiseConsoleMessages;
+      }
+    );
+
+    // Remove warningPatternHandler to stop handling the matched warning pattern
+    // and the task should not get any warning anymore.
+    warningPatternHandler = null;
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_isProbablyASignUpForm.js b/toolkit/components/passwordmgr/test/browser/browser_isProbablyASignUpForm.js
new file mode 100644
index 0000000000..cc8bc63e7a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_isProbablyASignUpForm.js
@@ -0,0 +1,52 @@
+"use strict";
+
+const TEST_URL = `https://example.com${DIRECTORY_PATH}form_signup_detection.html`;
+
+add_task(async () => {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_URL,
+    },
+    async browser => {
+      await SpecialPowers.spawn(browser, [], async () => {
+        const doc = content.document;
+        const { FormScenarios } = ChromeUtils.importESModule(
+          "resource://gre/modules/FormScenarios.sys.mjs"
+        );
+
+        function assertSignUpForm(
+          message,
+          formId,
+          inputId,
+          expectedToBeSignUp
+        ) {
+          const isSignUpForm = !!FormScenarios.detect({
+            form: doc.getElementById(formId),
+            input: doc.getElementById(inputId),
+          }).signUpForm;
+          Assert.equal(isSignUpForm, expectedToBeSignUp, message);
+        }
+
+        assertSignUpForm(
+          "Obvious signup form is detected as sign up form",
+          "obvious-signup-form",
+          "obvious-signup-email",
+          true
+        );
+        assertSignUpForm(
+          "Obvious non signup form is detected as non sign up form",
+          "obvious-login-form",
+          "obvious-login-username",
+          false
+        );
+        assertSignUpForm(
+          "An <input> HTML element is detected as non sign up form",
+          "",
+          "standalone-username",
+          false
+        );
+      });
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_localip_frame.js b/toolkit/components/passwordmgr/test/browser/browser_localip_frame.js
new file mode 100644
index 0000000000..33ae0e6c0b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_localip_frame.js
@@ -0,0 +1,86 @@
+"use strict";
+
+add_setup(async () => {
+  const login1 = LoginTestUtils.testData.formLogin({
+    origin: "http://10.0.0.0",
+    formActionOrigin: "https://example.org",
+    username: "username1",
+    password: "password1",
+  });
+  const login2 = LoginTestUtils.testData.formLogin({
+    origin: "https://example.org",
+    formActionOrigin: "https://example.org",
+    username: "username2",
+    password: "password2",
+  });
+  await Services.logins.addLogins([login1, login2]);
+});
+
+add_task(async function test_warningForLocalIP() {
+  let tests = [
+    /* when the url of top-level and iframe are both ip address, do not show insecure warning */
+    {
+      top: "http://192.168.0.0",
+      iframe: "http://10.0.0.0",
+      expected: `[originaltype="loginWithOrigin"]`,
+    },
+    {
+      top: "http://192.168.0.0",
+      iframe: "https://example.org",
+      expected: `[type="insecureWarning"]`,
+    },
+    {
+      top: "http://example.com",
+      iframe: "http://10.0.0.0",
+      expected: `[type="insecureWarning"]`,
+    },
+    {
+      top: "http://example.com",
+      iframe: "http://example.org",
+      expected: `[type="insecureWarning"]`,
+    },
+  ];
+
+  for (let test of tests) {
+    let urlTop = test.top + DIRECTORY_PATH + "empty.html";
+    let urlIframe =
+      test.iframe + DIRECTORY_PATH + "insecure_test_subframe.html";
+
+    let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, urlTop);
+    let browser = tab.linkedBrowser;
+
+    await SpecialPowers.spawn(browser, [urlIframe], async url => {
+      await new content.Promise(resolve => {
+        let ifr = content.document.createElement("iframe");
+        ifr.onload = resolve;
+        ifr.src = url;
+        content.document.body.appendChild(ifr);
+      });
+    });
+
+    let popup = document.getElementById("PopupAutoComplete");
+    Assert.ok(popup, "Got popup");
+
+    let ifr = browser.browsingContext.children[0];
+    Assert.ok(ifr, "Got iframe");
+
+    let popupShown = openACPopup(
+      popup,
+      tab.linkedBrowser,
+      "#form-basic-username",
+      ifr
+    );
+    await popupShown;
+
+    let item = popup.querySelector(test.expected);
+    Assert.ok(item, "Got expected richlistitem");
+
+    await BrowserTestUtils.waitForCondition(
+      () => !item.collapsed,
+      "Wait for autocomplete to show"
+    );
+
+    await closePopup(popup);
+    BrowserTestUtils.removeTab(tab);
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_message_onFormSubmit.js b/toolkit/components/passwordmgr/test/browser/browser_message_onFormSubmit.js
new file mode 100644
index 0000000000..5e611a7384
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_message_onFormSubmit.js
@@ -0,0 +1,82 @@
+/**
+ * Test "passwordmgr-form-submission-detected" should be notified
+ * regardless of whehter the password saving is enabled.
+ */
+
+async function waitForFormSubmissionDetected() {
+  return new Promise(resolve => {
+    Services.obs.addObserver(function observer(subject, topic) {
+      Services.obs.removeObserver(
+        observer,
+        "passwordmgr-form-submission-detected"
+      );
+      resolve();
+    }, "passwordmgr-form-submission-detected");
+  });
+}
+
+add_task(async function test_login_save_disable() {
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.rememberSignons", false]],
+  });
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url:
+        "https://example.com/browser/toolkit/components/" +
+        "passwordmgr/test/browser/form_basic.html",
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      await changeContentFormValues(browser, {
+        "#form-basic-username": "username",
+        "#form-basic-password": "password",
+      });
+
+      let promise = waitForFormSubmissionDetected();
+      await SpecialPowers.spawn(browser, [], async function () {
+        let doc = this.content.document;
+        doc.getElementById("form-basic").submit();
+      });
+
+      await promise;
+      Assert.ok(true, "Test completed");
+    }
+  );
+});
+
+add_task(async function test_login_save_enable() {
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.rememberSignons", true]],
+  });
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url:
+        "https://example.com/browser/toolkit/components/" +
+        "passwordmgr/test/browser/form_basic.html",
+    },
+    async function (browser) {
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+
+      await changeContentFormValues(browser, {
+        "#form-basic-username": "username",
+        "#form-basic-password": "password",
+      });
+
+      // When login saving is enabled, we should receive both FormSubmit
+      // event and "passwordmgr-form-submission-detected" event
+      let p1 = waitForFormSubmissionDetected();
+      let p2 = listenForTestNotification("ShowDoorhanger");
+      await SpecialPowers.spawn(browser, [], async function () {
+        let doc = this.content.document;
+        doc.getElementById("form-basic").submit();
+      });
+
+      await Promise.all([p1, p2]);
+      Assert.ok(true, "Test completed");
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_openPasswordManager.js b/toolkit/components/passwordmgr/test/browser/browser_openPasswordManager.js
new file mode 100644
index 0000000000..af5d70e259
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_openPasswordManager.js
@@ -0,0 +1,161 @@
+const { sinon } = ChromeUtils.importESModule(
+  "resource://testing-common/Sinon.sys.mjs"
+);
+
+add_task(async function test_noFilter() {
+  let openingFunc = () =>
+    LoginHelper.openPasswordManager(window, { entryPoint: "mainmenu" });
+  let passwordManager = await openPasswordManager(openingFunc);
+
+  Assert.ok(passwordManager, "Login dialog was opened");
+  await passwordManager.close();
+  await TestUtils.waitForCondition(() => {
+    return Services.wm.getMostRecentWindow("Toolkit:PasswordManager") === null;
+  }, "Waiting for the password manager dialog to close");
+});
+
+add_task(async function test_filter() {
+  // Greek IDN for example.test
+  let domain = "παράδειγμα.δοκιμή";
+  let openingFunc = () =>
+    LoginHelper.openPasswordManager(window, {
+      filterString: domain,
+      entryPoint: "mainmenu",
+    });
+  let passwordManager = await openPasswordManager(openingFunc, true);
+  Assert.equal(
+    passwordManager.filterValue,
+    domain,
+    "search string to filter logins should match expectation"
+  );
+  await passwordManager.close();
+  await TestUtils.waitForCondition(() => {
+    return Services.wm.getMostRecentWindow("Toolkit:PasswordManager") === null;
+  }, "Waiting for the password manager dialog to close");
+});
+
+add_task(async function test_management_noFilter() {
+  let tabOpenPromise = BrowserTestUtils.waitForNewTab(gBrowser, "about:logins");
+  LoginHelper.openPasswordManager(window, { entryPoint: "mainmenu" });
+  let tab = await tabOpenPromise;
+  Assert.ok(tab, "Got the new tab");
+  BrowserTestUtils.removeTab(tab);
+});
+
+add_task(async function test_management_filter() {
+  let tabOpenPromise = BrowserTestUtils.waitForNewTab(
+    gBrowser,
+    "about:logins?filter=%CF%80%CE%B1%CF%81%CE%AC%CE%B4%CE%B5%CE%B9%CE%B3%CE%BC%CE%B1.%CE%B4%CE%BF%CE%BA%CE%B9%CE%BC%CE%AE"
+  );
+  // Greek IDN for example.test
+  LoginHelper.openPasswordManager(window, {
+    filterString: "παράδειγμα.δοκιμή",
+    entryPoint: "mainmenu",
+  });
+  let tab = await tabOpenPromise;
+  Assert.ok(tab, "Got the new tab with a domain filter");
+  BrowserTestUtils.removeTab(tab);
+});
+
+add_task(
+  async function test_url_when_opening_password_manager_without_a_filterString() {
+    sinon.spy(window.gBrowser, "addTrustedTab");
+    const openingFunc = () =>
+      LoginHelper.openPasswordManager(window, {
+        filterString: "",
+        entryPoint: "mainmenu",
+      });
+    const passwordManager = await openPasswordManager(openingFunc);
+
+    const url = window.gBrowser.addTrustedTab.lastCall.args[0];
+
+    Assert.ok(
+      !url.includes("filter"),
+      "LoginHelper.openPasswordManager call without a filterString navigated to a URL with a filter query param"
+    );
+    Assert.equal(
+      0,
+      url.split("").filter(char => char === "&").length,
+      "LoginHelper.openPasswordManager call without a filterString navigated to a URL with an &"
+    );
+    Assert.equal(
+      url,
+      "about:logins?entryPoint=mainmenu",
+      "LoginHelper.openPasswordManager call without a filterString navigated to an unexpected URL"
+    );
+
+    Assert.ok(passwordManager, "Login dialog was opened");
+    await passwordManager.close();
+    window.gBrowser.addTrustedTab.restore();
+  }
+);
+
+add_task(
+  async function test_url_when_opening_password_manager_with_a_filterString() {
+    sinon.spy(window.gBrowser, "addTrustedTab");
+    const openingFunc = () =>
+      LoginHelper.openPasswordManager(window, {
+        filterString: "testFilter",
+        entryPoint: "mainmenu",
+      });
+    const passwordManager = await openPasswordManager(openingFunc);
+
+    const url = window.gBrowser.addTrustedTab.lastCall.args[0];
+
+    Assert.ok(
+      url.includes("filter"),
+      "LoginHelper.openPasswordManager call with a filterString navigated to a URL without a filter query param"
+    );
+    Assert.equal(
+      1,
+      url.split("").filter(char => char === "&").length,
+      "LoginHelper.openPasswordManager call with a filterString navigated to a URL without the correct number of '&'s"
+    );
+    Assert.equal(
+      url,
+      "about:logins?filter=testFilter&entryPoint=mainmenu",
+      "LoginHelper.openPasswordManager call with a filterString navigated to an unexpected URL"
+    );
+
+    Assert.ok(passwordManager, "Login dialog was opened");
+    await passwordManager.close();
+    window.gBrowser.addTrustedTab.restore();
+  }
+);
+
+add_task(
+  async function test_url_when_opening_password_manager_without_filterString_or_entryPoint() {
+    sinon.spy(window.gBrowser, "addTrustedTab");
+    const openingFunc = () =>
+      LoginHelper.openPasswordManager(window, {
+        filterString: "",
+        entryPoint: "",
+      });
+    const passwordManager = await openPasswordManager(openingFunc);
+
+    const url = window.gBrowser.addTrustedTab.lastCall.args[0];
+
+    Assert.ok(
+      !url.includes("filter"),
+      "LoginHelper.openPasswordManager call without a filterString navigated to a URL with a filter query param"
+    );
+    Assert.ok(
+      !url.includes("entryPoint"),
+      "LoginHelper.openPasswordManager call without an entryPoint navigated to a URL with an entryPoint query param"
+    );
+    Assert.equal(
+      0,
+      url.split("").filter(char => char === "&").length,
+      "LoginHelper.openPasswordManager call without query params navigated to a URL that included at least one '&'"
+    );
+    Assert.equal(
+      url,
+      "about:logins",
+      "LoginHelper.openPasswordManager call without a filterString or entryPoint navigated to an unexpected URL"
+    );
+
+    Assert.ok(passwordManager, "Login dialog was opened");
+    await passwordManager.close();
+    window.gBrowser.addTrustedTab.restore();
+  }
+);
diff --git a/toolkit/components/passwordmgr/test/browser/browser_preselect_login.js b/toolkit/components/passwordmgr/test/browser/browser_preselect_login.js
new file mode 100644
index 0000000000..5847e84282
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_preselect_login.js
@@ -0,0 +1,247 @@
+const TEST_ORIGIN = "https://example.org";
+const ABOUT_LOGINS_ORIGIN = "about:logins";
+const TEST_URL_PATH = `${TEST_ORIGIN}${DIRECTORY_PATH}form_basic_login.html`;
+
+const LOGINS_DATA = [
+  {
+    origin: "https://aurl.com",
+    username: "user1",
+    password: "pass1",
+    guid: Services.uuid.generateUUID().toString(),
+  },
+  {
+    origin: TEST_ORIGIN,
+    username: "user2",
+    password: "pass2",
+    guid: Services.uuid.generateUUID().toString(),
+  },
+  {
+    origin: TEST_ORIGIN,
+    username: "user3",
+    password: "pass3",
+    guid: Services.uuid.generateUUID().toString(),
+  },
+];
+
+const waitForAppMenu = async () => {
+  const appMenu = document.getElementById("appMenu-popup");
+  const appMenuButton = document.getElementById("PanelUI-menu-button");
+  await TestUtils.waitForCondition(
+    () => BrowserTestUtils.isVisible(appMenuButton),
+    "App menu button should be visible."
+  );
+
+  let popupshown = BrowserTestUtils.waitForEvent(appMenu, "popupshown");
+  EventUtils.synthesizeMouseAtCenter(appMenuButton, {});
+  await popupshown;
+  Assert.equal(
+    appMenu.state,
+    "open",
+    `Menu panel (${appMenu.id}) should be visible`
+  );
+};
+
+const isExpectedLoginItemSelected = async ({ expectedGuid }) => {
+  const loginList = content.document.querySelector("login-list").shadowRoot;
+
+  await ContentTaskUtils.waitForCondition(
+    () =>
+      loginList.querySelector("login-list-item[aria-selected='true']")?.dataset
+        ?.guid === expectedGuid,
+    "Wait for login item to be selected"
+  );
+
+  Assert.equal(
+    loginList.querySelector("login-list-item[aria-selected='true']")?.dataset
+      ?.guid,
+    expectedGuid,
+    "Expected login is preselected"
+  );
+};
+
+add_setup(async () => {
+  await Services.logins.addLogins(
+    LOGINS_DATA.map(login => LoginTestUtils.testData.formLogin(login))
+  );
+});
+
+add_task(async function test_about_logins_defaults_to_first_item() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "about:logins#random-guid",
+    },
+    async function (gBrowser) {
+      await SpecialPowers.spawn(
+        gBrowser,
+        [{ expectedGuid: LOGINS_DATA[0].guid }],
+        isExpectedLoginItemSelected
+      );
+
+      Assert.ok(
+        true,
+        "First item of the list is selected when random hash is supplied."
+      );
+    }
+  );
+});
+
+add_task(
+  async function test_gear_icon_opens_about_logins_with_preselected_login() {
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url: TEST_URL_PATH,
+      },
+      async function (browser) {
+        const popup = document.getElementById("PopupAutoComplete");
+
+        await openACPopup(popup, browser, "#form-basic-username");
+
+        const secondLoginItem = popup.firstChild.getItemAtIndex(1);
+        const secondLoginItemSecondaryAction = secondLoginItem.querySelector(
+          ".ac-secondary-action"
+        );
+
+        Assert.ok(
+          !secondLoginItemSecondaryAction.checkVisibility({
+            checkVisibilityCSS: true,
+          }),
+          "Secondary action should not be visible initially"
+        );
+
+        await EventUtils.synthesizeKey("KEY_ArrowDown");
+        await EventUtils.synthesizeKey("KEY_ArrowDown");
+
+        await BrowserTestUtils.waitForCondition(
+          () => secondLoginItem.attributes.selected,
+          "Wait for second login to become active"
+        );
+
+        Assert.ok(
+          secondLoginItemSecondaryAction.checkVisibility({
+            checkVisibilityCSS: true,
+          }),
+          "Secondary action should be visible when item is active"
+        );
+
+        const aboutLoginsTabPromise = BrowserTestUtils.waitForNewTab(
+          gBrowser,
+          url => url.includes(ABOUT_LOGINS_ORIGIN),
+          true
+        );
+
+        EventUtils.synthesizeMouseAtCenter(secondLoginItemSecondaryAction, {});
+        const aboutLoginsTab = await aboutLoginsTabPromise;
+
+        await SpecialPowers.spawn(
+          aboutLoginsTab.linkedBrowser,
+          [{ expectedGuid: LOGINS_DATA[2].guid }],
+          isExpectedLoginItemSelected
+        );
+
+        await closePopup(popup);
+        gBrowser.removeTab(aboutLoginsTab);
+      }
+    );
+  }
+);
+
+add_task(
+  async function test_password_menu_opens_about_logins_with_preselected_login() {
+    await BrowserTestUtils.withNewTab(
+      {
+        gBrowser,
+        url: TEST_URL_PATH,
+      },
+      async function (browser) {
+        await waitForAppMenu();
+
+        const appMenuPasswordsButton = document.getElementById(
+          "appMenu-passwords-button"
+        );
+
+        const aboutLoginsTabPromise = BrowserTestUtils.waitForNewTab(
+          gBrowser,
+          url => url.includes(ABOUT_LOGINS_ORIGIN),
+          true
+        );
+
+        EventUtils.synthesizeMouseAtCenter(appMenuPasswordsButton, {});
+
+        const aboutLoginsTab = await aboutLoginsTabPromise;
+
+        await SpecialPowers.spawn(
+          aboutLoginsTab.linkedBrowser,
+          [{ expectedGuid: LOGINS_DATA[1].guid }],
+          isExpectedLoginItemSelected
+        );
+
+        gBrowser.removeTab(aboutLoginsTab);
+      }
+    );
+  }
+);
+
+add_task(async function test_new_login_url_has_correct_hash() {
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "about:logins",
+    },
+    async function (gBrowser) {
+      await SpecialPowers.spawn(gBrowser, [], async () => {
+        const loginList =
+          content.document.querySelector("login-list").shadowRoot;
+        const createLoginButton = loginList
+          .querySelector("create-login-button")
+          .shadowRoot.querySelector("button");
+
+        createLoginButton.click();
+
+        await ContentTaskUtils.waitForCondition(
+          () =>
+            ContentTaskUtils.isVisible(
+              loginList.querySelector("#new-login-list-item")
+            ),
+          "Wait for new login-list-item to become visible"
+        );
+
+        Assert.equal(
+          content.location.hash,
+          "",
+          "Location hash should be empty"
+        );
+      });
+    }
+  );
+});
+
+add_task(async function test_no_logins_empty_url_hash() {
+  Services.logins.removeAllUserFacingLogins();
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_URL_PATH,
+    },
+    async function () {
+      await waitForAppMenu();
+
+      const appMenuPasswordsButton = document.getElementById(
+        "appMenu-passwords-button"
+      );
+
+      const aboutLoginsTabPromise = BrowserTestUtils.waitForNewTab(
+        gBrowser,
+        url => new URL(url).hash === "",
+        true
+      );
+
+      EventUtils.synthesizeMouseAtCenter(appMenuPasswordsButton, {});
+
+      const aboutLoginsTab = await aboutLoginsTabPromise;
+
+      gBrowser.removeTab(aboutLoginsTab);
+    }
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_private_window.js b/toolkit/components/passwordmgr/test/browser/browser_private_window.js
new file mode 100644
index 0000000000..31fe82cf8b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_private_window.js
@@ -0,0 +1,954 @@
+"use strict";
+
+async function focusWindow(win) {
+  if (Services.focus.activeWindow == win) {
+    return;
+  }
+  let promise = new Promise(resolve => {
+    win.addEventListener(
+      "focus",
+      function () {
+        resolve();
+      },
+      { capture: true, once: true }
+    );
+  });
+  win.focus();
+  await promise;
+}
+
+function getDialogDoc() {
+  // Trudge through all the open windows, until we find the one
+  // that has either commonDialog.xhtml or selectDialog.xhtml loaded.
+  // var enumerator = Services.wm.getEnumerator("navigator:browser");
+  for (let { docShell } of Services.wm.getEnumerator(null)) {
+    var containedDocShells = docShell.getAllDocShellsInSubtree(
+      docShell.typeChrome,
+      docShell.ENUMERATE_FORWARDS
+    );
+    for (let childDocShell of containedDocShells) {
+      // Get the corresponding document for this docshell
+      // We don't want it if it's not done loading.
+      if (childDocShell.busyFlags != Ci.nsIDocShell.BUSY_FLAGS_NONE) {
+        continue;
+      }
+      var childDoc = childDocShell.docViewer.DOMDocument;
+      if (
+        childDoc.location.href !=
+          "chrome://global/content/commonDialog.xhtml" &&
+        childDoc.location.href != "chrome://global/content/selectDialog.xhtml"
+      ) {
+        continue;
+      }
+
+      // We're expecting the dialog to be focused. If it's not yet, try later.
+      // (In particular, this is needed on Linux to reliably check focused elements.)
+      if (Services.focus.focusedWindow != childDoc.defaultView) {
+        continue;
+      }
+
+      return childDoc;
+    }
+  }
+
+  return null;
+}
+
+async function waitForAuthPrompt() {
+  let promptDoc = await TestUtils.waitForCondition(() => {
+    return getAuthPrompt();
+  });
+  info("Got prompt: " + promptDoc);
+  return promptDoc;
+}
+
+function getAuthPrompt() {
+  let doc = getDialogDoc();
+  if (!doc) {
+    return false; // try again in a bit
+  }
+  return doc;
+}
+
+async function loadAccessRestrictedURL(browser, url, username, password) {
+  let browserLoaded = BrowserTestUtils.browserLoaded(browser);
+  BrowserTestUtils.startLoadingURIString(browser, url);
+
+  // Wait for the auth prompt, enter the login details and close the prompt
+  await PromptTestUtils.handleNextPrompt(
+    browser,
+    { modalType: authPromptModalType, promptType: "promptUserAndPass" },
+    { buttonNumClick: 0, loginInput: username, passwordInput: password }
+  );
+
+  await SimpleTest.promiseFocus(browser.ownerGlobal);
+  await browserLoaded;
+}
+
+const PRIVATE_BROWSING_CAPTURE_PREF = "signon.privateBrowsingCapture.enabled";
+let nsLoginInfo = new Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  Ci.nsILoginInfo,
+  "init"
+);
+let login = new nsLoginInfo(
+  "https://example.com",
+  "https://example.com",
+  null,
+  "notifyu1",
+  "notifyp1",
+  "user",
+  "pass"
+);
+const form1Url = `https://example.com/${DIRECTORY_PATH}subtst_privbrowsing_1.html`;
+const form2Url = `https://example.com/${DIRECTORY_PATH}form_password_change.html`;
+const authUrl = `https://example.com/${DIRECTORY_PATH}authenticate.sjs`;
+
+let normalWin;
+let privateWin;
+let authPromptModalType;
+
+// XXX: Note that tasks are currently run in sequence. Some tests may assume the state
+// resulting from successful or unsuccessful logins in previous tasks
+
+add_task(async function test_setup() {
+  authPromptModalType = Services.prefs.getIntPref("prompts.modalType.httpAuth");
+  normalWin = await BrowserTestUtils.openNewBrowserWindow({ private: false });
+  privateWin = await BrowserTestUtils.openNewBrowserWindow({ private: true });
+  Services.logins.removeAllUserFacingLogins();
+});
+
+add_task(async function test_normal_popup_notification_1() {
+  info("test 1: run outside of private mode, popup notification should appear");
+  await focusWindow(normalWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: normalWin.gBrowser,
+      url: form1Url,
+    },
+    async function (browser) {
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {
+          "#user": "notifyu1",
+          "#pass": "notifyp1",
+        }
+      );
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+
+      let notif = getCaptureDoorhanger(
+        "password-save",
+        PopupNotifications,
+        browser
+      );
+      Assert.ok(notif, "got notification popup");
+      if (notif) {
+        await TestUtils.waitForCondition(
+          () => !notif.dismissed,
+          "notification should not be dismissed"
+        );
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+});
+
+add_task(async function test_private_popup_notification_2() {
+  info(
+    "test 2: run inside of private mode, dismissed popup notification should appear"
+  );
+
+  const capturePrefValue = Services.prefs.getBoolPref(
+    PRIVATE_BROWSING_CAPTURE_PREF
+  );
+  Assert.ok(
+    capturePrefValue,
+    `Expect ${PRIVATE_BROWSING_CAPTURE_PREF} to default to true`
+  );
+
+  // clear existing logins for parity with the previous test
+  Services.logins.removeAllUserFacingLogins();
+  await focusWindow(privateWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: privateWin.gBrowser,
+      url: form1Url,
+    },
+    async function (browser) {
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {
+          "#user": "notifyu1",
+          "#pass": "notifyp1",
+        }
+      );
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+
+      let notif = getCaptureDoorhanger(
+        "password-save",
+        PopupNotifications,
+        browser
+      );
+      Assert.ok(notif, "Expected notification popup");
+      if (notif) {
+        await TestUtils.waitForCondition(
+          () => notif.dismissed,
+          "notification should be dismissed"
+        );
+
+        let { panel } = privateWin.PopupNotifications;
+        let promiseShown = BrowserTestUtils.waitForEvent(panel, "popupshown");
+        notif.anchorElement.click();
+        await promiseShown;
+
+        let notificationElement = panel.childNodes[0];
+        let toggleCheckbox = notificationElement.querySelector(
+          "#password-notification-visibilityToggle"
+        );
+
+        Assert.ok(
+          !toggleCheckbox.hidden,
+          "Toggle should be visible upon 1st opening"
+        );
+
+        info("Hiding popup.");
+        let promiseHidden = BrowserTestUtils.waitForEvent(panel, "popuphidden");
+        panel.hidePopup();
+        await promiseHidden;
+
+        info("Clicking on anchor to reshow popup.");
+        promiseShown = BrowserTestUtils.waitForEvent(panel, "popupshown");
+        notif.anchorElement.click();
+        await promiseShown;
+
+        Assert.ok(
+          toggleCheckbox.hidden,
+          "Toggle should be hidden upon 2nd opening"
+        );
+
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "No logins were saved"
+  );
+});
+
+add_task(async function test_private_popup_notification_no_capture_pref_2b() {
+  info(
+    "test 2b: run inside of private mode, with capture pref off," +
+      "popup notification should not appear"
+  );
+
+  const capturePrefValue = Services.prefs.getBoolPref(
+    PRIVATE_BROWSING_CAPTURE_PREF
+  );
+  Services.prefs.setBoolPref(PRIVATE_BROWSING_CAPTURE_PREF, false);
+
+  // clear existing logins for parity with the previous test
+  Services.logins.removeAllUserFacingLogins();
+
+  await focusWindow(privateWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: privateWin.gBrowser,
+      url: form1Url,
+    },
+    async function (browser) {
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {
+          "#user": "notifyu1",
+          "#pass": "notifyp1",
+        }
+      );
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+
+      let notif = getCaptureDoorhanger(
+        "password-save",
+        PopupNotifications,
+        browser
+      );
+      // restore the pref to its original value
+      Services.prefs.setBoolPref(
+        PRIVATE_BROWSING_CAPTURE_PREF,
+        capturePrefValue
+      );
+
+      Assert.ok(!notif, "Expected no notification popup");
+      if (notif) {
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "No logins were saved"
+  );
+});
+
+add_task(async function test_normal_popup_notification_3() {
+  info(
+    "test 3: run with a login, outside of private mode, " +
+      "match existing username/password: no popup notification should appear"
+  );
+
+  Services.logins.removeAllUserFacingLogins();
+  await Services.logins.addLoginAsync(login);
+  let allLogins = await Services.logins.getAllLogins();
+  // Sanity check the HTTP login exists.
+  Assert.equal(allLogins.length, 1, "Should have the HTTP login");
+  let timeLastUsed = allLogins[0].timeLastUsed;
+  let loginGuid = allLogins[0].guid;
+
+  await focusWindow(normalWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: normalWin.gBrowser,
+      url: form1Url,
+    },
+    async function (browser) {
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {
+          "#user": "notifyu1",
+          "#pass": "notifyp1",
+        }
+      );
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+
+      let notif = getCaptureDoorhanger("any", PopupNotifications, browser);
+      Assert.ok(!notif, "got no notification popup");
+      if (notif) {
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+  allLogins = await Services.logins.getAllLogins();
+  Assert.equal(
+    allLogins[0].guid,
+    loginGuid,
+    "Sanity-check we are comparing the same login record"
+  );
+  Assert.ok(
+    allLogins[0].timeLastUsed > timeLastUsed,
+    "The timeLastUsed timestamp has been updated"
+  );
+});
+
+add_task(async function test_private_popup_notification_3b() {
+  info(
+    "test 3b: run with a login, in private mode," +
+      " match existing username/password: no popup notification should appear"
+  );
+
+  Services.logins.removeAllUserFacingLogins();
+  await Services.logins.addLoginAsync(login);
+  let allLogins = await Services.logins.getAllLogins();
+  // Sanity check the HTTP login exists.
+  Assert.equal(allLogins.length, 1, "Should have the HTTP login");
+  let timeLastUsed = allLogins[0].timeLastUsed;
+  let loginGuid = allLogins[0].guid;
+
+  await focusWindow(privateWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: privateWin.gBrowser,
+      url: form1Url,
+    },
+    async function (browser) {
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {
+          "#user": "notifyu1",
+          "#pass": "notifyp1",
+        }
+      );
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+
+      let notif = getCaptureDoorhanger("any", PopupNotifications, browser);
+
+      Assert.ok(!notif, "got no notification popup");
+      if (notif) {
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+  allLogins = await Services.logins.getAllLogins();
+  Assert.equal(
+    allLogins[0].guid,
+    loginGuid,
+    "Sanity-check we are comparing the same login record"
+  );
+  Assert.equal(
+    allLogins[0].timeLastUsed,
+    timeLastUsed,
+    "The timeLastUsed timestamp has not been updated"
+  );
+});
+
+add_task(async function test_normal_new_password_4() {
+  info(
+    "test 4: run with a login, outside of private mode," +
+      " add a new password: popup notification should appear"
+  );
+  Services.logins.removeAllUserFacingLogins();
+  await Services.logins.addLoginAsync(login);
+  let allLogins = await Services.logins.getAllLogins();
+  // Sanity check the HTTP login exists.
+  Assert.equal(allLogins.length, 1, "Should have the HTTP login");
+  let timeLastUsed = allLogins[0].timeLastUsed;
+  let loginGuid = allLogins[0].guid;
+
+  await focusWindow(normalWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: normalWin.gBrowser,
+      url: form2Url,
+    },
+    async function (browser) {
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {
+          "#pass": "notifyp1",
+          "#newpass": "notifyp2",
+        }
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger(
+        "password-change",
+        PopupNotifications,
+        browser
+      );
+      Assert.ok(notif, "got notification popup");
+      if (notif) {
+        await TestUtils.waitForCondition(
+          () => !notif.dismissed,
+          "notification should not be dismissed"
+        );
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+  // We put up a doorhanger, but didn't interact with it, so we expect the login timestamps
+  // to be unchanged
+  allLogins = await Services.logins.getAllLogins();
+  Assert.equal(
+    allLogins[0].guid,
+    loginGuid,
+    "Sanity-check we are comparing the same login record"
+  );
+  Assert.equal(
+    allLogins[0].timeLastUsed,
+    timeLastUsed,
+    "The timeLastUsed timestamp was not updated"
+  );
+});
+
+add_task(async function test_private_new_password_5() {
+  info(
+    "test 5: run with a login, in private mode," +
+      "add a new password: popup notification should appear"
+  );
+
+  const capturePrefValue = Services.prefs.getBoolPref(
+    PRIVATE_BROWSING_CAPTURE_PREF
+  );
+  Assert.ok(
+    capturePrefValue,
+    `Expect ${PRIVATE_BROWSING_CAPTURE_PREF} to default to true`
+  );
+
+  let allLogins = await Services.logins.getAllLogins();
+  // Sanity check the HTTP login exists.
+  Assert.equal(allLogins.length, 1, "Should have the HTTP login");
+  let timeLastUsed = allLogins[0].timeLastUsed;
+  let loginGuid = allLogins[0].guid;
+
+  await focusWindow(privateWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: privateWin.gBrowser,
+      url: form2Url,
+    },
+    async function (browser) {
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {
+          "#pass": "notifyp1",
+          "#newpass": "notifyp2",
+        }
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger(
+        "password-change",
+        PopupNotifications,
+        browser
+      );
+      Assert.ok(notif, "Expected notification popup");
+      if (notif) {
+        await TestUtils.waitForCondition(
+          () => !notif.dismissed,
+          "notification should not be dismissed"
+        );
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+  // We put up a doorhanger, but didn't interact with it, so we expect the login timestamps
+  // to be unchanged
+  allLogins = await Services.logins.getAllLogins();
+  Assert.equal(
+    allLogins[0].guid,
+    loginGuid,
+    "Sanity-check we are comparing the same login record"
+  );
+  Assert.equal(
+    allLogins[0].timeLastUsed,
+    timeLastUsed,
+    "The timeLastUsed timestamp has not been updated"
+  );
+});
+
+add_task(async function test_normal_with_login_6() {
+  info(
+    "test 6: run with a login, outside of private mode, " +
+      "submit with an existing password (from test 4): popup notification should appear"
+  );
+
+  await focusWindow(normalWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: normalWin.gBrowser,
+      url: form2Url,
+    },
+    async function (browser) {
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {
+          "#pass": "notifyp1",
+          "#newpass": "notifyp2",
+        }
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+      let notif = getCaptureDoorhanger(
+        "password-change",
+        PopupNotifications,
+        browser
+      );
+      Assert.ok(notif, "got notification popup");
+      if (notif) {
+        await TestUtils.waitForCondition(
+          () => !notif.dismissed,
+          "notification should not be dismissed"
+        );
+        await cleanupDoorhanger(notif);
+      }
+      Services.logins.removeLogin(login);
+    }
+  );
+});
+
+add_task(async function test_normal_autofilled_7() {
+  info("test 7: verify that the user/pass pair was autofilled");
+  await Services.logins.addLoginAsync(login);
+
+  // Sanity check the HTTP login exists.
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    1,
+    "Should have the HTTP login"
+  );
+
+  await focusWindow(normalWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: normalWin.gBrowser,
+      url: "about:blank",
+    },
+    async function (browser) {
+      // Add the observer before loading the form page
+      let formFilled = listenForTestNotification("FormProcessed");
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      BrowserTestUtils.startLoadingURIString(browser, form1Url);
+      await formFilled;
+
+      // the form should have been autofilled, so submit without updating field values
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {}
+      );
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+    }
+  );
+});
+
+add_task(async function test_private_not_autofilled_8() {
+  info("test 8: verify that the user/pass pair was not autofilled");
+  // Sanity check the HTTP login exists.
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    1,
+    "Should have the HTTP login"
+  );
+
+  let formFilled = listenForTestNotification("FormProcessed");
+
+  await focusWindow(privateWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: privateWin.gBrowser,
+      url: form1Url,
+    },
+    async function (browser) {
+      await formFilled;
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {}
+      );
+      Assert.ok(!fieldValues.username, "Checking submitted username");
+      Assert.ok(!fieldValues.password, "Checking submitted password");
+    }
+  );
+});
+
+// Disabled for Bug 1523777
+// add_task(async function test_private_autocomplete_9() {
+//   info("test 9: verify that the user/pass pair was available for autocomplete");
+//   // Sanity check the HTTP login exists.
+//   Assert.equal((await Services.logins.getAllLogins()).length, 1, "Should have the HTTP login");
+
+//   await focusWindow(privateWin);
+//   await BrowserTestUtils.withNewTab({
+//     gBrowser: privateWin.gBrowser,
+//     url: form1Url,
+//   }, async function(browser) {
+//     let popup = document.getElementById("PopupAutoComplete");
+//     Assert.ok(popup, "Got popup");
+
+//     let promiseShown = BrowserTestUtils.waitForEvent(popup, "popupshown");
+
+//     // focus the user field. This should trigger the autocomplete menu
+//     await ContentTask.spawn(browser, null, async function() {
+//       content.document.getElementById("user").focus();
+//     });
+//     await promiseShown;
+//     Assert.ok(promiseShown, "autocomplete shown");
+
+//     let promiseFormInput = ContentTask.spawn(browser, null, async function() {
+//       let doc = content.document;
+//       await new Promise(resolve => {
+//         doc.getElementById("form").addEventListener("input", resolve, { once: true });
+//       });
+//     });
+//     info("sending keys");
+//     // select the item and hit enter to fill the form
+//     await BrowserTestUtils.synthesizeKey("VK_DOWN", {}, browser);
+//     await BrowserTestUtils.synthesizeKey("VK_DOWN", {}, browser);
+//     await BrowserTestUtils.synthesizeKey("VK_RETURN", {}, browser);
+//     await promiseFormInput;
+
+//     let fieldValues = await submitFormAndGetResults(browser, "formsubmit.sjs", {});
+//     Assert.equal(fieldValues.username, "notifyu1", "Checking submitted username");
+//     Assert.equal(fieldValues.password, "notifyp1", "Checking submitted password");
+//   });
+// });
+
+add_task(async function test_normal_autofilled_10() {
+  info(
+    "test 10: verify that the user/pass pair does get autofilled in non-private window"
+  );
+  // Sanity check the HTTP login exists.
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    1,
+    "Should have the HTTP login"
+  );
+
+  let formFilled = listenForTestNotification("FormProcessed");
+
+  await focusWindow(normalWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: normalWin.gBrowser,
+      url: form1Url,
+    },
+    async function (browser) {
+      await formFilled;
+      let fieldValues = await submitFormAndGetResults(
+        browser,
+        "formsubmit.sjs",
+        {}
+      );
+      Assert.equal(
+        fieldValues.username,
+        "notifyu1",
+        "Checking submitted username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "notifyp1",
+        "Checking submitted password"
+      );
+    }
+  );
+});
+
+add_task(async function test_normal_http_basic_auth() {
+  info(
+    "test normal/basic-auth: verify that we get a doorhanger after basic-auth login"
+  );
+  Services.logins.removeAllUserFacingLogins();
+  clearHttpAuths();
+
+  await focusWindow(normalWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: normalWin.gBrowser,
+      url: "https://example.com",
+    },
+    async function (browser) {
+      await loadAccessRestrictedURL(browser, authUrl, "test", "testpass");
+      Assert.ok(true, "Auth-required page loaded");
+
+      // verify result in the response document
+      let fieldValues = await SpecialPowers.spawn(
+        browser,
+        [[]],
+        async function () {
+          let username = content.document.getElementById("user").textContent;
+          let password = content.document.getElementById("pass").textContent;
+          let ok = content.document.getElementById("ok").textContent;
+          return {
+            username,
+            password,
+            ok,
+          };
+        }
+      );
+      Assert.equal(fieldValues.ok, "PASS", "Checking authorization passed");
+      Assert.equal(
+        fieldValues.username,
+        "test",
+        "Checking authorized username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "testpass",
+        "Checking authorized password"
+      );
+
+      let notif = getCaptureDoorhanger(
+        "password-save",
+        PopupNotifications,
+        browser
+      );
+      Assert.ok(notif, "got notification popup");
+      if (notif) {
+        await TestUtils.waitForCondition(
+          () => !notif.dismissed,
+          "notification should not be dismissed"
+        );
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+});
+
+add_task(async function test_private_http_basic_auth() {
+  info(
+    "test private/basic-auth: verify that we don't get a doorhanger after basic-auth login"
+  );
+  Services.logins.removeAllUserFacingLogins();
+  clearHttpAuths();
+
+  const capturePrefValue = Services.prefs.getBoolPref(
+    PRIVATE_BROWSING_CAPTURE_PREF
+  );
+  Assert.ok(
+    capturePrefValue,
+    `Expect ${PRIVATE_BROWSING_CAPTURE_PREF} to default to true`
+  );
+
+  await focusWindow(privateWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: privateWin.gBrowser,
+      url: "https://example.com",
+    },
+    async function (browser) {
+      await loadAccessRestrictedURL(browser, authUrl, "test", "testpass");
+
+      let fieldValues = await getFormSubmitResponseResult(
+        browser,
+        "authenticate.sjs"
+      );
+      Assert.equal(
+        fieldValues.username,
+        "test",
+        "Checking authorized username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "testpass",
+        "Checking authorized password"
+      );
+
+      let notif = getCaptureDoorhanger(
+        "password-save",
+        PopupNotifications,
+        browser
+      );
+      Assert.ok(notif, "got notification popup");
+      if (notif) {
+        await TestUtils.waitForCondition(
+          () => notif.dismissed,
+          "notification should be dismissed"
+        );
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+});
+
+add_task(async function test_private_http_basic_auth_no_capture_pref() {
+  info(
+    "test private/basic-auth: verify that we don't get a doorhanger after basic-auth login" +
+      "with capture pref off"
+  );
+
+  const capturePrefValue = Services.prefs.getBoolPref(
+    PRIVATE_BROWSING_CAPTURE_PREF
+  );
+  Services.prefs.setBoolPref(PRIVATE_BROWSING_CAPTURE_PREF, false);
+
+  Services.logins.removeAllUserFacingLogins();
+  clearHttpAuths();
+
+  await focusWindow(privateWin);
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser: privateWin.gBrowser,
+      url: "https://example.com",
+    },
+    async function (browser) {
+      await loadAccessRestrictedURL(browser, authUrl, "test", "testpass");
+
+      let fieldValues = await getFormSubmitResponseResult(
+        browser,
+        "authenticate.sjs"
+      );
+      Assert.equal(
+        fieldValues.username,
+        "test",
+        "Checking authorized username"
+      );
+      Assert.equal(
+        fieldValues.password,
+        "testpass",
+        "Checking authorized password"
+      );
+
+      let notif = getCaptureDoorhanger(
+        "password-save",
+        PopupNotifications,
+        browser
+      );
+      // restore the pref to its original value
+      Services.prefs.setBoolPref(
+        PRIVATE_BROWSING_CAPTURE_PREF,
+        capturePrefValue
+      );
+
+      Assert.ok(!notif, "got no notification popup");
+      if (notif) {
+        await cleanupDoorhanger(notif);
+      }
+    }
+  );
+});
+
+add_task(async function test_cleanup() {
+  await BrowserTestUtils.closeWindow(normalWin);
+  await BrowserTestUtils.closeWindow(privateWin);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_proxyAuth_prompt.js b/toolkit/components/passwordmgr/test/browser/browser_proxyAuth_prompt.js
new file mode 100644
index 0000000000..478f204581
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_proxyAuth_prompt.js
@@ -0,0 +1,182 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+let proxyChannel;
+
+function initProxy() {
+  return new Promise(resolve => {
+    let proxyChannel;
+
+    let proxyCallback = {
+      QueryInterface: ChromeUtils.generateQI(["nsIProtocolProxyCallback"]),
+
+      onProxyAvailable(req, uri, pi, status) {
+        class ProxyChannelListener {
+          onStartRequest(request) {
+            resolve(proxyChannel);
+          }
+          onStopRequest(request, status) {}
+        }
+        // I'm cheating a bit here... We should probably do some magic foo to get
+        // something implementing nsIProxiedProtocolHandler and then call
+        // NewProxiedChannel(), so we have something that's definately a proxied
+        // channel. But Mochitests use a proxy for a number of hosts, so just
+        // requesting a normal channel will give us a channel that's proxied.
+        // The proxyChannel needs to move to at least on-modify-request to
+        // have valid ProxyInfo, but we use OnStartRequest during startup()
+        // for simplicity.
+        proxyChannel = Services.io.newChannel(
+          "http://mochi.test:8888",
+          null,
+          null,
+          null, // aLoadingNode
+          Services.scriptSecurityManager.getSystemPrincipal(),
+          null, // aTriggeringPrincipal
+          Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL,
+          Ci.nsIContentPolicy.TYPE_OTHER
+        );
+        proxyChannel.asyncOpen(new ProxyChannelListener());
+      },
+    };
+
+    // Need to allow for arbitrary network servers defined in PAC instead of a hardcoded moz-proxy.
+    let pps = Cc["@mozilla.org/network/protocol-proxy-service;1"].getService();
+
+    let channel = Services.io.newChannel(
+      "https://example.com",
+      null,
+      null,
+      null, // aLoadingNode
+      Services.scriptSecurityManager.getSystemPrincipal(),
+      null, // aTriggeringPrincipal
+      Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL,
+      Ci.nsIContentPolicy.TYPE_OTHER
+    );
+    pps.asyncResolve(channel, 0, proxyCallback);
+  });
+}
+
+add_setup(async function () {
+  await SpecialPowers.pushPrefEnv({
+    // This test relies on tab auth prompts.
+    set: [["prompts.modalType.httpAuth", Services.prompt.MODAL_TYPE_TAB]],
+  });
+  proxyChannel = await initProxy();
+});
+
+/**
+ * Create an object for consuming an nsIAuthPromptCallback.
+ * @returns result
+ * @returns {nsIAuthPromptCallback} result.callback - Callback to be passed into
+ * asyncPromptAuth.
+ * @returns {Promise} result.promise - Promise which resolves with authInfo once
+ * the callback has been called.
+ */
+function getAuthPromptCallback() {
+  let callbackResolver;
+  let promise = new Promise(resolve => {
+    callbackResolver = resolve;
+  });
+  let callback = {
+    onAuthAvailable(context, authInfo) {
+      callbackResolver(authInfo);
+    },
+  };
+  return { callback, promise };
+}
+
+/**
+ * Tests that if a window proxy auth prompt is open, subsequent auth calls with
+ * matching realm will be merged into the existing prompt. This should work even
+ * if the follwing auth call has browser parent.
+ */
+add_task(async function testProxyAuthPromptMerge() {
+  let tabA = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    "https://example.com"
+  );
+  let tabB = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    "https://example.org"
+  );
+
+  const promptFac = Cc[
+    "@mozilla.org/passwordmanager/authpromptfactory;1"
+  ].getService(Ci.nsIPromptFactory);
+  let prompter = promptFac.getPrompt(window, Ci.nsIAuthPrompt2);
+
+  let level = Ci.nsIAuthPrompt2.LEVEL_NONE;
+  let proxyAuthinfo = {
+    username: "",
+    password: "",
+    domain: "",
+    flags: Ci.nsIAuthInformation.AUTH_PROXY,
+    authenticationScheme: "basic",
+    realm: "",
+  };
+
+  // The next prompt call will result in window prompt, because the prompt does
+  // not have a browser set yet. The browser is used as a parent for tab
+  // prompts.
+  let promptOpened = PromptTestUtils.waitForPrompt(null, {
+    modalType: Services.prompt.MODAL_TYPE_WINDOW,
+  });
+  let cbWinPrompt = getAuthPromptCallback();
+  info("asyncPromptAuth no parent");
+  prompter.asyncPromptAuth(
+    proxyChannel,
+    cbWinPrompt.callback,
+    null,
+    level,
+    proxyAuthinfo
+  );
+  let prompt = await promptOpened;
+
+  // Set a browser so the next prompt would open as tab prompt.
+  prompter.QueryInterface(Ci.nsILoginManagerAuthPrompter).browser =
+    tabA.linkedBrowser;
+
+  // Since we already have an open window prompts, subsequent calls with
+  // matching realm should be merged into this prompt and no additional prompts
+  // must be spawned.
+  let cbNoPrompt = getAuthPromptCallback();
+  info("asyncPromptAuth tabA parent");
+  prompter.asyncPromptAuth(
+    proxyChannel,
+    cbNoPrompt.callback,
+    null,
+    level,
+    proxyAuthinfo
+  );
+
+  // Switch to the next tabs browser.
+  prompter.QueryInterface(Ci.nsILoginManagerAuthPrompter).browser =
+    tabB.linkedBrowser;
+
+  let cbNoPrompt2 = getAuthPromptCallback();
+  info("asyncPromptAuth tabB parent");
+  prompter.asyncPromptAuth(
+    proxyChannel,
+    cbNoPrompt2.callback,
+    null,
+    level,
+    proxyAuthinfo
+  );
+
+  // Accept the prompt.
+  PromptTestUtils.handlePrompt(prompt, {});
+
+  // Accepting the window prompts should complete all auth requests.
+  let authInfo1 = await cbWinPrompt.promise;
+  Assert.ok(authInfo1, "Received callback from first proxy auth call.");
+  let authInfo2 = await cbNoPrompt.promise;
+  Assert.ok(authInfo2, "Received callback from second proxy auth call.");
+  let authInfo3 = await cbNoPrompt2.promise;
+  Assert.ok(authInfo3, "Received callback from third proxy auth call.");
+
+  BrowserTestUtils.removeTab(tabA);
+  BrowserTestUtils.removeTab(tabB);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_relay_telemetry.js b/toolkit/components/passwordmgr/test/browser/browser_relay_telemetry.js
new file mode 100644
index 0000000000..ea5a25db79
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_relay_telemetry.js
@@ -0,0 +1,534 @@
+const { sinon } = ChromeUtils.importESModule(
+  "resource://testing-common/Sinon.sys.mjs"
+);
+const { HttpServer } = ChromeUtils.importESModule(
+  "resource://testing-common/httpd.sys.mjs"
+);
+const { getFxAccountsSingleton } = ChromeUtils.importESModule(
+  "resource://gre/modules/FxAccounts.sys.mjs"
+);
+const { FirefoxRelayTelemetry } = ChromeUtils.importESModule(
+  "resource://gre/modules/FirefoxRelayTelemetry.mjs"
+);
+
+const gFxAccounts = getFxAccountsSingleton();
+let gRelayACOptionsTitles;
+let gHttpServer;
+
+const TEST_URL_PATH = `https://example.org${DIRECTORY_PATH}form_basic_signup.html`;
+
+const MOCK_MASKS = [
+  {
+    full_address: "email1@mozilla.com",
+    description: "Email 1 Description",
+    enabled: true,
+  },
+  {
+    full_address: "email2@mozilla.com",
+    description: "Email 2 Description",
+    enabled: false,
+  },
+  {
+    full_address: "email3@mozilla.com",
+    description: "Email 3 Description",
+    enabled: true,
+  },
+];
+
+const SERVER_SCENARIOS = {
+  free_tier_limit: {
+    "/relayaddresses/": {
+      POST: (request, response) => {
+        response.setStatusLine(request.httpVersion, 403);
+        response.write(JSON.stringify({ error_code: "free_tier_limit" }));
+      },
+      GET: (_, response) => {
+        response.write(JSON.stringify(MOCK_MASKS));
+      },
+    },
+  },
+  unknown_error: {
+    "/relayaddresses/": {
+      default: (request, response) => {
+        response.setStatusLine(request.httpVersion, 408);
+      },
+    },
+  },
+
+  default: {
+    default: (request, response) => {
+      response.setStatusLine(request.httpVersion, 200);
+      response.write(JSON.stringify({ foo: "bar" }));
+    },
+  },
+};
+
+const simpleRouter = scenarioName => (request, response) => {
+  const routeHandler =
+    SERVER_SCENARIOS[scenarioName][request._path] ?? SERVER_SCENARIOS.default;
+  const methodHandler =
+    routeHandler?.[request._method] ??
+    routeHandler.default ??
+    SERVER_SCENARIOS.default.default;
+  methodHandler(request, response);
+};
+const setupServerScenario = (scenarioName = "default") =>
+  gHttpServer.registerPrefixHandler("/", simpleRouter(scenarioName));
+
+const setupRelayScenario = async scenarioName => {
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.firefoxRelay.feature", scenarioName]],
+  });
+  Services.telemetry.clearEvents();
+};
+
+const collectRelayTelemeryEvent = sameFlow => {
+  const collectedEvents = TelemetryTestUtils.getEvents(
+    { category: "relay_integration" },
+    { process: "parent" }
+  );
+
+  return sameFlow
+    ? collectedEvents.filter((event, _, arr) => event.value === arr[0].value)
+    : collectedEvents;
+};
+
+const waitForEvents = async (expectedEvents, sameFlow) => {
+  await TestUtils.waitForCondition(
+    () =>
+      (collectRelayTelemeryEvent(sameFlow)?.length ?? 0) >=
+      (expectedEvents.length ?? 0),
+    "Wait for telemetry to be collected",
+    100,
+    100
+  );
+  return collectRelayTelemeryEvent(sameFlow);
+};
+
+async function assertEvents(expectedEvents, sameFlow = true) {
+  // To avoid intermittent failures, we wait for telemetry to be collected
+  const events = await waitForEvents(expectedEvents, sameFlow);
+  for (let i = 0; i < expectedEvents.length; i++) {
+    const keysInExpectedEvent = Object.keys(expectedEvents[i]);
+    keysInExpectedEvent.forEach(key => {
+      const assertFn =
+        typeof events[i][key] === "object"
+          ? Assert.deepEqual.bind(Assert)
+          : Assert.equal.bind(Assert);
+      assertFn(
+        events[i][key],
+        expectedEvents[i][key],
+        `Key value for ${key} should match`
+      );
+    });
+  }
+}
+
+async function openRelayAC(browser) {
+  // In rare cases, especially in chaos mode in verify tests, some events creep in.
+  // Clear them out before we start.
+  Services.telemetry.clearEvents();
+  const popup = document.getElementById("PopupAutoComplete");
+  await openACPopup(popup, browser, "#form-basic-username");
+  const popupItem = document
+    .querySelector("richlistitem")
+    .getAttribute("ac-value");
+
+  Assert.ok(
+    gRelayACOptionsTitles.some(title => title.value === popupItem),
+    "AC Popup has an item Relay option shown in popup"
+  );
+
+  const promiseHidden = BrowserTestUtils.waitForEvent(popup, "popuphidden");
+  popup.firstChild.getItemAtIndex(0).click();
+  await promiseHidden;
+}
+
+// Bug 1832782: On OSX opt verify mode, the test exceeds the default timeout.
+requestLongerTimeout(2);
+
+add_setup(async function () {
+  gHttpServer = new HttpServer();
+  setupServerScenario();
+
+  gHttpServer.start(-1);
+
+  const API_ENDPOINT = `http://localhost:${gHttpServer.identity.primaryPort}/`;
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["signon.firefoxRelay.feature", "available"],
+      ["signon.firefoxRelay.base_url", API_ENDPOINT],
+    ],
+  });
+
+  sinon.stub(gFxAccounts, "hasLocalSession").returns(true);
+  sinon
+    .stub(gFxAccounts.constructor.config, "isProductionConfig")
+    .returns(true);
+  sinon.stub(gFxAccounts, "getOAuthToken").returns("MOCK_TOKEN");
+  sinon.stub(gFxAccounts, "getSignedInUser").returns({
+    email: "example@mozilla.com",
+  });
+
+  const canRecordExtendedOld = Services.telemetry.canRecordExtended;
+  Services.telemetry.canRecordExtended = true;
+  Services.telemetry.clearEvents();
+  Services.telemetry.setEventRecordingEnabled("relay_integration", true);
+
+  gRelayACOptionsTitles = await new Localization([
+    "browser/firefoxRelay.ftl",
+    "toolkit/branding/brandings.ftl",
+  ]).formatMessages([
+    "firefox-relay-opt-in-title-1",
+    "firefox-relay-use-mask-title",
+  ]);
+
+  registerCleanupFunction(async () => {
+    await new Promise(resolve => {
+      gHttpServer.stop(function () {
+        resolve();
+      });
+    });
+    Services.telemetry.setEventRecordingEnabled("relay_integration", false);
+    Services.telemetry.clearEvents();
+    Services.telemetry.canRecordExtended = canRecordExtendedOld;
+    sinon.restore();
+  });
+});
+
+add_task(async function test_pref_toggle() {
+  await setupRelayScenario("available");
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: "about:preferences#privacy",
+    },
+    async function (browser) {
+      const relayIntegrationCheckbox = content.document.querySelector(
+        "checkbox#relayIntegration"
+      );
+      relayIntegrationCheckbox.click();
+      relayIntegrationCheckbox.click();
+      await assertEvents([
+        { object: "pref_change", method: "disabled" },
+        { object: "pref_change", method: "enabled" },
+      ]);
+    }
+  );
+});
+
+add_task(async function test_popup_option_optin_enabled() {
+  await setupRelayScenario("available");
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_URL_PATH,
+    },
+    async function (browser) {
+      await openRelayAC(browser);
+      const notificationPopup = document.getElementById("notification-popup");
+      const notificationShown = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "shown"
+      );
+      const notificationHidden = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "hidden"
+      );
+
+      await notificationShown;
+
+      notificationPopup
+        .querySelector("button.popup-notification-primary-button")
+        .click();
+
+      await Promise.all([
+        notificationHidden,
+        BrowserTestUtils.waitForEvent(ConfirmationHint._panel, "popuphidden"),
+        TestUtils.waitForPrefChange("signon.firefoxRelay.feature"),
+      ]);
+
+      await assertEvents([
+        {
+          object: "offer_relay",
+          method: "shown",
+          extra: { scenario: "SignUpFormScenario" },
+        },
+        {
+          object: "offer_relay",
+          method: "clicked",
+          extra: { scenario: "SignUpFormScenario" },
+        },
+        { object: "opt_in_panel", method: "shown" },
+        { object: "opt_in_panel", method: "enabled" },
+      ]);
+
+      Services.telemetry.clearEvents();
+
+      // Retrigger AC popup
+      await SpecialPowers.spawn(browser, [], async function () {
+        const usernameInput = content.document.querySelector(
+          "#form-basic-username"
+        );
+        usernameInput.blur();
+        usernameInput.focus();
+      });
+
+      await assertEvents([
+        {
+          object: "fill_username",
+          method: "shown",
+          extra: { error_code: "0" },
+        },
+      ]);
+    }
+  );
+});
+
+add_task(async function test_popup_option_optin_postponed() {
+  await setupRelayScenario("available");
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_URL_PATH,
+    },
+    async function (browser) {
+      await openRelayAC(browser);
+      const notificationPopup = document.getElementById("notification-popup");
+      const notificationShown = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "shown"
+      );
+      const notificationHidden = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "hidden"
+      );
+
+      await notificationShown;
+
+      notificationPopup
+        .querySelector("button.popup-notification-secondary-button")
+        .click();
+
+      await notificationHidden;
+
+      await assertEvents([
+        { object: "offer_relay", method: "shown" },
+        { object: "offer_relay", method: "clicked" },
+        { object: "opt_in_panel", method: "shown" },
+        { object: "opt_in_panel", method: "postponed" },
+      ]);
+    }
+  );
+});
+
+add_task(async function test_popup_option_optin_disabled() {
+  await setupRelayScenario("available");
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_URL_PATH,
+    },
+    async function (browser) {
+      await openRelayAC(browser);
+      const notificationPopup = document.getElementById("notification-popup");
+      const notificationShown = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "shown"
+      );
+      const notificationHidden = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "hidden"
+      );
+
+      await notificationShown;
+      const menupopup = notificationPopup.querySelector("menupopup");
+      const menuitem = menupopup.querySelector("menuitem");
+
+      menuitem.click();
+      await notificationHidden;
+
+      await assertEvents([
+        { object: "offer_relay", method: "shown" },
+        { object: "offer_relay", method: "clicked" },
+        { object: "opt_in_panel", method: "shown" },
+        { object: "opt_in_panel", method: "disabled" },
+      ]);
+    }
+  );
+});
+
+add_task(async function test_popup_option_fillusername() {
+  await setupRelayScenario("enabled");
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_URL_PATH,
+    },
+    async function (browser) {
+      await openRelayAC(browser);
+      await BrowserTestUtils.waitForEvent(
+        ConfirmationHint._panel,
+        "popuphidden"
+      );
+      await assertEvents([
+        { object: "fill_username", method: "shown" },
+        {
+          object: "fill_username",
+          method: "clicked",
+        },
+      ]);
+    }
+  );
+});
+
+add_task(async function test_fillusername_free_tier_limit() {
+  await setupRelayScenario("enabled");
+  setupServerScenario("free_tier_limit");
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_URL_PATH,
+    },
+    async function (browser) {
+      await openRelayAC(browser);
+
+      const notificationPopup = document.getElementById("notification-popup");
+      const notificationShown = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "shown"
+      );
+      const notificationHidden = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "hidden"
+      );
+
+      await notificationShown;
+      notificationPopup.querySelector(".reusable-relay-masks button").click();
+      await notificationHidden;
+
+      await assertEvents([
+        { object: "fill_username", method: "shown" },
+        {
+          object: "fill_username",
+          method: "clicked",
+        },
+        {
+          object: "fill_username",
+          method: "shown",
+          extra: { error_code: "free_tier_limit" },
+        },
+        {
+          object: "reuse_panel",
+          method: "shown",
+        },
+        {
+          object: "reuse_panel",
+          method: "reuse_mask",
+        },
+      ]);
+
+      await SpecialPowers.spawn(browser, [], async function () {
+        const username = content.document.getElementById("form-basic-username");
+        Assert.equal(
+          username.value,
+          "email1@mozilla.com",
+          "Username field should be filled with the first mask"
+        );
+      });
+    }
+  );
+});
+
+add_task(async function test_fillusername_error() {
+  await setupRelayScenario("enabled");
+  setupServerScenario("unknown_error");
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_URL_PATH,
+    },
+    async function (browser) {
+      await openRelayAC(browser);
+
+      const notificationPopup = document.getElementById("notification-popup");
+      const notificationShown = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "shown"
+      );
+
+      await notificationShown;
+      Assert.equal(
+        notificationPopup.querySelector("popupnotification").id,
+        "relay-integration-error-notification",
+        "Error message should be displayed"
+      );
+
+      await assertEvents([
+        { object: "fill_username", method: "shown" },
+        {
+          object: "fill_username",
+          method: "clicked",
+        },
+        {
+          object: "reuse_panel",
+          method: "shown",
+          extra: { error_code: "408" },
+        },
+      ]);
+    }
+  );
+});
+
+add_task(async function test_auth_token_error() {
+  setupRelayScenario("enabled");
+  gFxAccounts.getOAuthToken.restore();
+  const oauthTokenStub = sinon.stub(gFxAccounts, "getOAuthToken").throws();
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: TEST_URL_PATH,
+    },
+    async function (browser) {
+      await openRelayAC(browser);
+      const notificationPopup = document.getElementById("notification-popup");
+      const notificationShown = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "shown"
+      );
+      const notificationHidden = BrowserTestUtils.waitForPopupEvent(
+        notificationPopup,
+        "hidden"
+      );
+
+      await notificationShown;
+
+      notificationPopup
+        .querySelector("button.popup-notification-primary-button")
+        .click();
+
+      await notificationHidden;
+
+      await assertEvents([
+        {
+          object: "fill_username",
+          method: "shown",
+          extra: { error_code: "0" },
+        },
+        {
+          object: "fill_username",
+          method: "clicked",
+          extra: { error_code: "0" },
+        },
+        {
+          object: "fill_username",
+          method: "shown",
+          extra: { error_code: "418" },
+        },
+      ]);
+    }
+  );
+  oauthTokenStub.restore();
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_telemetry_SignUpFormRuleset.js b/toolkit/components/passwordmgr/test/browser/browser_telemetry_SignUpFormRuleset.js
new file mode 100644
index 0000000000..dc8ac9c081
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_telemetry_SignUpFormRuleset.js
@@ -0,0 +1,53 @@
+"use strict";
+
+const SIGNUP_DETECTION_HISTOGRAM = "PWMGR_SIGNUP_FORM_DETECTION_MS";
+const TEST_URL = `https://example.com${DIRECTORY_PATH}form_signup_detection.html`;
+
+/**
+ *
+ * @param {Object} histogramData The histogram data to examine
+ * @returns The amount of entries found in the histogram data
+ */
+function countEntries(histogramData) {
+  return histogramData
+    ? Object.values(histogramData.values).reduce((a, b) => a + b, 0)
+    : null;
+}
+
+/**
+ * @param {String} id The histogram to examine
+ * @param {Number} expected The expected amount of entries for a histogram
+ */
+async function countEntriesOfChildHistogram(id, expected) {
+  let histogram;
+  await TestUtils.waitForCondition(() => {
+    let histograms = Services.telemetry.getSnapshotForHistograms(
+      "main",
+      false
+    ).content;
+
+    histogram = histograms[id];
+
+    return !!histogram && countEntries(histogram) == expected;
+  }, `The histogram ${id} was expected to have ${expected} entries.`);
+  Assert.equal(countEntries(histogram), expected);
+}
+
+add_setup(async () => {
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.signupDetection.enabled", true]],
+  });
+  Services.telemetry.getHistogramById(SIGNUP_DETECTION_HISTOGRAM).clear();
+});
+
+add_task(async () => {
+  let formProcessed = listenForTestNotification("FormProcessed", 2);
+
+  let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, TEST_URL);
+
+  await formProcessed;
+
+  await countEntriesOfChildHistogram(SIGNUP_DETECTION_HISTOGRAM, 2);
+
+  gBrowser.removeTab(tab);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_test_changeContentInputValue.js b/toolkit/components/passwordmgr/test/browser/browser_test_changeContentInputValue.js
new file mode 100644
index 0000000000..d0016708b2
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_test_changeContentInputValue.js
@@ -0,0 +1,129 @@
+/**
+ * Tests head.js#changeContentInputValue.
+ */
+
+"use strict";
+
+// The origin for the test URIs.
+const TEST_ORIGIN = "https://example.com";
+const BASIC_FORM_PAGE_PATH = DIRECTORY_PATH + "form_basic.html";
+const USERNAME_INPUT_SELECTOR = "#form-basic-username";
+
+let testCases = [
+  {
+    name: "blank string should clear input value",
+    originalValue: "start text",
+    inputEvent: "",
+    expectedKeypresses: ["Backspace"],
+  },
+  {
+    name: "input value that adds to original string should only add the difference",
+    originalValue: "start text",
+    inputEvent: "start text!!!",
+    expectedKeypresses: ["!", "!", "!"],
+  },
+  {
+    name: "input value that is a subset of original string should only delete the difference",
+    originalValue: "start text",
+    inputEvent: "start",
+    expectedKeypresses: ["Backspace"],
+  },
+  {
+    name: "input value that is unrelated to the original string should replace it",
+    originalValue: "start text",
+    inputEvent: "wut?",
+    expectedKeypresses: ["w", "u", "t", "?"],
+  },
+];
+
+for (let testData of testCases) {
+  let tmp = {
+    async [testData.name]() {
+      await testStringChange(testData);
+    },
+  };
+  add_task(tmp[testData.name]);
+}
+
+async function testStringChange({
+  name,
+  originalValue,
+  inputEvent,
+  expectedKeypresses,
+}) {
+  info("Starting test " + name);
+  await LoginTestUtils.clearData();
+
+  await LoginTestUtils.addLogin({
+    username: originalValue,
+    password: "password",
+  });
+
+  let formProcessedPromise = listenForTestNotification("FormProcessed");
+  let url = TEST_ORIGIN + BASIC_FORM_PAGE_PATH;
+  info("Opening tab with url: " + url);
+
+  await BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url,
+    },
+    async function (browser) {
+      info(`Opened tab with url: ${url}, waiting for focus`);
+      await SimpleTest.promiseFocus(browser.ownerGlobal);
+      info("Waiting for form-processed message");
+      await formProcessedPromise;
+      await checkForm(browser, originalValue);
+      info("form checked");
+
+      await ContentTask.spawn(
+        browser,
+        { USERNAME_INPUT_SELECTOR, expectedKeypresses },
+        async function ({ USERNAME_INPUT_SELECTOR, expectedKeypresses }) {
+          let input = content.document.querySelector(USERNAME_INPUT_SELECTOR);
+
+          let verifyKeyListener = event => {
+            Assert.equal(
+              expectedKeypresses[0],
+              event.key,
+              "Key press matches expected value"
+            );
+            expectedKeypresses.shift();
+
+            if (!expectedKeypresses.length) {
+              input.removeEventListner("keydown", verifyKeyListener);
+              input.addEventListener("keydown", () => {
+                throw new Error("Unexpected keypress encountered");
+              });
+            }
+          };
+
+          input.addEventListener("keydown", verifyKeyListener);
+        }
+      );
+
+      changeContentInputValue(browser, USERNAME_INPUT_SELECTOR, inputEvent);
+    }
+  );
+}
+
+async function checkForm(browser, expectedUsername) {
+  await ContentTask.spawn(
+    browser,
+    {
+      expectedUsername,
+      USERNAME_INPUT_SELECTOR,
+    },
+    async function contentCheckForm({
+      expectedUsername,
+      USERNAME_INPUT_SELECTOR,
+    }) {
+      let field = content.document.querySelector(USERNAME_INPUT_SELECTOR);
+      Assert.equal(
+        field.value,
+        expectedUsername,
+        `Username field has teh expected initial value '${expectedUsername}'`
+      );
+    }
+  );
+}
diff --git a/toolkit/components/passwordmgr/test/browser/browser_username_only_form_telemetry.js b/toolkit/components/passwordmgr/test/browser/browser_username_only_form_telemetry.js
new file mode 100644
index 0000000000..54304c24ac
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_username_only_form_telemetry.js
@@ -0,0 +1,198 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/* eslint-disable mozilla/no-arbitrary-setTimeout */
+
+"use strict";
+
+async function setupForms(numUsernameOnly, numBasic, numOther) {
+  const TEST_HOSTNAME = "https://example.com";
+  let tab = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    TEST_HOSTNAME + DIRECTORY_PATH + "empty.html"
+  );
+
+  await SpecialPowers.spawn(
+    tab.linkedBrowser,
+    [
+      {
+        numUsernameOnly,
+        numBasic,
+      },
+    ],
+    async function (data) {
+      // type: 1: basic, 2:usernameOnly, 3:other
+      function addForm(type) {
+        const form = content.document.createElement("form");
+        content.document.body.appendChild(form);
+
+        const user = content.document.createElement("input");
+        if (type === 3) {
+          user.type = "url";
+        } else {
+          user.type = "text";
+          user.autocomplete = "username";
+        }
+        form.appendChild(user);
+
+        if (type === 1) {
+          const password = content.document.createElement("input");
+          password.type = "password";
+          form.appendChild(password);
+        }
+      }
+      for (let i = 0; i < data.numBasic; i++) {
+        addForm(1);
+      }
+      for (let i = 0; i < data.numUsernameOnly; i++) {
+        addForm(2);
+      }
+      for (let i = 0; i < data.numOther; i++) {
+        addForm(3);
+      }
+    }
+  );
+
+  return tab;
+}
+
+async function checkChildHistogram(id, index, expected) {
+  let histogram;
+  await TestUtils.waitForCondition(() => {
+    let histograms = Services.telemetry.getSnapshotForHistograms(
+      "main",
+      false /* clear */
+    ).content;
+
+    histogram = histograms[id];
+    return !!histogram && histogram.values[index] == expected;
+  });
+  Assert.equal(histogram.values[index], expected);
+}
+
+add_setup(async function () {
+  SpecialPowers.pushPrefEnv({
+    set: [
+      ["signon.usernameOnlyForm.enabled", true],
+      ["signon.usernameOnlyForm.lookupThreshold", 100], // ignore the threshold in test
+    ],
+  });
+
+  // Wait 1sec to make sure all the telemetry data recorded prior to the beginning of the
+  // test is cleared.
+  await new Promise(res => setTimeout(res, 1000));
+  Services.telemetry.getSnapshotForHistograms("main", true /* clear */);
+});
+
+add_task(async function test_oneUsernameOnlyForm() {
+  const numUsernameOnlyForms = 1;
+  const numBasicForms = 0;
+
+  // number of "other" forms doesn't change the outcome, set it to 2 here and
+  // in the following testcase just to ensure it doesn't affect the result.
+  let tab = await setupForms(numUsernameOnlyForms, numBasicForms, 2);
+
+  await checkChildHistogram(
+    "PWMGR_IS_USERNAME_ONLY_FORM",
+    1,
+    numUsernameOnlyForms
+  );
+  await checkChildHistogram(
+    "PWMGR_NUM_FORM_HAS_POSSIBLE_USERNAME_EVENT_PER_DOC",
+    numUsernameOnlyForms,
+    1
+  );
+
+  BrowserTestUtils.removeTab(tab);
+  Services.telemetry.getSnapshotForHistograms("main", true /* clear */);
+});
+
+add_task(async function test_multipleUsernameOnlyForms() {
+  const numUsernameOnlyForms = 3;
+  const numBasicForms = 2;
+
+  let tab = await setupForms(numUsernameOnlyForms, numBasicForms, 2);
+
+  await checkChildHistogram(
+    "PWMGR_IS_USERNAME_ONLY_FORM",
+    1,
+    numUsernameOnlyForms
+  );
+  await checkChildHistogram(
+    "PWMGR_NUM_FORM_HAS_POSSIBLE_USERNAME_EVENT_PER_DOC",
+    5,
+    1
+  );
+
+  BrowserTestUtils.removeTab(tab);
+  Services.telemetry.getSnapshotForHistograms("main", true /* clear */);
+});
+
+add_task(async function test_multipleDocument() {
+  // The first document
+  let numUsernameOnlyForms1 = 2;
+  let numBasicForms1 = 2;
+
+  let tab1 = await setupForms(numUsernameOnlyForms1, numBasicForms1, 2);
+
+  await checkChildHistogram(
+    "PWMGR_IS_USERNAME_ONLY_FORM",
+    1,
+    numUsernameOnlyForms1
+  );
+  await checkChildHistogram(
+    "PWMGR_NUM_FORM_HAS_POSSIBLE_USERNAME_EVENT_PER_DOC",
+    numUsernameOnlyForms1 + numBasicForms1,
+    1
+  );
+
+  // The second document
+  let numUsernameOnlyForms2 = 15;
+  let numBasicForms2 = 3;
+
+  let tab2 = await setupForms(numUsernameOnlyForms2, numBasicForms2, 2);
+
+  await checkChildHistogram(
+    "PWMGR_IS_USERNAME_ONLY_FORM",
+    1,
+    numUsernameOnlyForms1 + numUsernameOnlyForms2
+  );
+
+  // the result is stacked, so the new document add a counter to all
+  // buckets under "numUsernameOnlyForms2 + numBasicForms2"
+  await checkChildHistogram(
+    "PWMGR_NUM_FORM_HAS_POSSIBLE_USERNAME_EVENT_PER_DOC",
+    numUsernameOnlyForms1 + numBasicForms1,
+    2
+  );
+  await checkChildHistogram(
+    "PWMGR_NUM_FORM_HAS_POSSIBLE_USERNAME_EVENT_PER_DOC",
+    numUsernameOnlyForms2 + numBasicForms2,
+    1
+  );
+
+  BrowserTestUtils.removeTab(tab1);
+  BrowserTestUtils.removeTab(tab2);
+  Services.telemetry.getSnapshotForHistograms("main", true /* clear */);
+});
+
+add_task(async function test_tooManyUsernameOnlyForms() {
+  const numUsernameOnlyForms = 25;
+  const numBasicForms = 2;
+
+  let tab = await setupForms(numUsernameOnlyForms, numBasicForms, 2);
+
+  await checkChildHistogram(
+    "PWMGR_IS_USERNAME_ONLY_FORM",
+    1,
+    numUsernameOnlyForms
+  );
+  await checkChildHistogram(
+    "PWMGR_NUM_FORM_HAS_POSSIBLE_USERNAME_EVENT_PER_DOC",
+    21,
+    numUsernameOnlyForms + numBasicForms - 20 // maximum is 20
+  );
+
+  BrowserTestUtils.removeTab(tab);
+  Services.telemetry.getSnapshotForHistograms("main", true /* clear */);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/browser_username_select_dialog.js b/toolkit/components/passwordmgr/test/browser/browser_username_select_dialog.js
new file mode 100644
index 0000000000..126ea20968
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/browser_username_select_dialog.js
@@ -0,0 +1,177 @@
+/*
+ * Test username selection dialog, on password update from a p-only form,
+ * when there are multiple saved logins on the domain.
+ */
+
+// Copied from prompt_common.js. TODO: share the code.
+function getSelectDialogDoc() {
+  // Trudge through all the open windows, until we find the one
+  // that has selectDialog.xhtml loaded.
+  // var enumerator = Services.wm.getEnumerator("navigator:browser");
+  for (let { docShell } of Services.wm.getEnumerator(null)) {
+    var containedDocShells = docShell.getAllDocShellsInSubtree(
+      docShell.typeChrome,
+      docShell.ENUMERATE_FORWARDS
+    );
+    for (let childDocShell of containedDocShells) {
+      // We don't want it if it's not done loading.
+      if (childDocShell.busyFlags != Ci.nsIDocShell.BUSY_FLAGS_NONE) {
+        continue;
+      }
+      var childDoc = childDocShell.docViewer.DOMDocument;
+
+      if (
+        childDoc.location.href == "chrome://global/content/selectDialog.xhtml"
+      ) {
+        return childDoc;
+      }
+    }
+  }
+
+  return null;
+}
+
+let nsLoginInfo = new Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  Ci.nsILoginInfo,
+  "init"
+);
+let login1 = new nsLoginInfo(
+  "https://example.com",
+  "https://example.com",
+  null,
+  "notifyu1",
+  "notifyp1",
+  "user",
+  "pass"
+);
+let login1B = new nsLoginInfo(
+  "https://example.com",
+  "https://example.com",
+  null,
+  "notifyu1B",
+  "notifyp1B",
+  "user",
+  "pass"
+);
+
+add_task(async function test_changeUPLoginOnPUpdateForm_accept() {
+  info(
+    "Select an u+p login from multiple logins, on password update form, and accept."
+  );
+  await Services.logins.addLogins([login1, login1B]);
+
+  let selectDialogPromise = TestUtils.topicObserved("select-dialog-loaded");
+
+  await testSubmittingLoginForm(
+    "subtst_notifications_change_p.html",
+    async function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "pass2",
+        "Checking submitted password"
+      );
+
+      info("Waiting for select dialog to appear.");
+      let doc = (await selectDialogPromise)[0].document;
+      let dialog = doc.getElementsByTagName("dialog")[0];
+      let listbox = doc.getElementById("list");
+
+      Assert.equal(listbox.selectedIndex, 0, "Checking selected index");
+      Assert.equal(listbox.itemCount, 2, "Checking selected length");
+      ["notifyu1", "notifyu1B"].forEach((username, i) => {
+        Assert.equal(
+          listbox.getItemAtIndex(i).label,
+          username,
+          "Check username selection on dialog"
+        );
+      });
+
+      dialog.acceptDialog();
+
+      await TestUtils.waitForCondition(() => {
+        return !getSelectDialogDoc();
+      }, "Wait for selection dialog to disappear.");
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 2, "Should have 2 logins");
+
+  let login = SpecialPowers.wrap(logins[0]).QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username unchanged");
+  Assert.equal(login.password, "pass2", "Check the password changed");
+  Assert.equal(login.timesUsed, 2, "Check times used");
+
+  login = SpecialPowers.wrap(logins[1]).QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1B", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1B", "Check the password unchanged");
+  Assert.equal(login.timesUsed, 1, "Check times used");
+
+  // cleanup
+  login1.password = "pass2";
+  Services.logins.removeLogin(login1);
+  login1.password = "notifyp1";
+
+  Services.logins.removeLogin(login1B);
+});
+
+add_task(async function test_changeUPLoginOnPUpdateForm_cancel() {
+  info(
+    "Select an u+p login from multiple logins, on password update form, and cancel."
+  );
+  await Services.logins.addLogins([login1, login1B]);
+
+  let selectDialogPromise = TestUtils.topicObserved("select-dialog-loaded");
+
+  await testSubmittingLoginForm(
+    "subtst_notifications_change_p.html",
+    async function (fieldValues) {
+      Assert.equal(fieldValues.username, "null", "Checking submitted username");
+      Assert.equal(
+        fieldValues.password,
+        "pass2",
+        "Checking submitted password"
+      );
+
+      info("Waiting for select dialog to appear.");
+      let doc = (await selectDialogPromise)[0].document;
+      let dialog = doc.getElementsByTagName("dialog")[0];
+      let listbox = doc.getElementById("list");
+
+      Assert.equal(listbox.selectedIndex, 0, "Checking selected index");
+      Assert.equal(listbox.itemCount, 2, "Checking selected length");
+      ["notifyu1", "notifyu1B"].forEach((username, i) => {
+        Assert.equal(
+          listbox.getItemAtIndex(i).label,
+          username,
+          "Check username selection on dialog"
+        );
+      });
+
+      dialog.cancelDialog();
+
+      await TestUtils.waitForCondition(() => {
+        return !getSelectDialogDoc();
+      }, "Wait for selection dialog to disappear.");
+    }
+  );
+
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 2, "Should have 2 logins");
+
+  let login = SpecialPowers.wrap(logins[0]).QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1", "Check the password unchanged");
+  Assert.equal(login.timesUsed, 1, "Check times used");
+
+  login = SpecialPowers.wrap(logins[1]).QueryInterface(Ci.nsILoginMetaInfo);
+  Assert.equal(login.username, "notifyu1B", "Check the username unchanged");
+  Assert.equal(login.password, "notifyp1B", "Check the password unchanged");
+  Assert.equal(login.timesUsed, 1, "Check times used");
+
+  // cleanup
+  Services.logins.removeLogin(login1);
+  Services.logins.removeLogin(login1B);
+});
diff --git a/toolkit/components/passwordmgr/test/browser/empty.html b/toolkit/components/passwordmgr/test/browser/empty.html
new file mode 100644
index 0000000000..1ad28bb1f7
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/empty.html
@@ -0,0 +1,8 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+<title>Empty file</title>
+</head>
+<body>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/file_focus_before_DOMContentLoaded.sjs b/toolkit/components/passwordmgr/test/browser/file_focus_before_DOMContentLoaded.sjs
new file mode 100644
index 0000000000..b99246c166
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/file_focus_before_DOMContentLoaded.sjs
@@ -0,0 +1,35 @@
+/**
+ * Focus a username field before DOMContentLoaded.
+ */
+
+"use strict";
+
+const DELAY = 2 * 1000; // Delay two seconds before completing the request.
+
+// In an SJS file we need to get the setTimeout bits ourselves, despite
+// what eslint might think applies for browser tests.
+// eslint-disable-next-line mozilla/no-redeclare-with-import-autofix
+let { setTimeout } = ChromeUtils.importESModule(
+  "resource://gre/modules/Timer.sys.mjs"
+);
+
+function handleRequest(request, response) {
+  response.processAsync();
+
+  response.setHeader("Content-Type", "text/html;charset=utf-8", false);
+  response.setHeader("Cache-Control", "no-cache", false);
+  response.write(`
+    <!DOCTYPE html><html><body>
+      <form id="early_focus_form" action="https://autocomplete:8888/formtest.js">
+        <input  type="text" id="uname" name="uname">
+        <input  type="password" id="pword" name="pword">
+        <button type="submit">Submit</button>
+      </form>
+      <script>document.querySelector("#uname").focus();</script>
+  `);
+
+  setTimeout(function finishOutput() {
+    response.write(`</body></html>`);
+    response.finish();
+  }, DELAY);
+}
diff --git a/toolkit/components/passwordmgr/test/browser/form_autofocus_frame.html b/toolkit/components/passwordmgr/test/browser/form_autofocus_frame.html
new file mode 100644
index 0000000000..3a145a9ea8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_autofocus_frame.html
@@ -0,0 +1,10 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head>
+<body>
+<form id="form-basic">
+  <input id="form-basic-username" name="username" autofocus>
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-submit" type="submit">
+</form>
+<iframe src="/document-builder.sjs?html=<html><body>Hi</body></html>"></iframe>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_autofocus_js.html b/toolkit/components/passwordmgr/test/browser/form_autofocus_js.html
new file mode 100644
index 0000000000..76056e3751
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_autofocus_js.html
@@ -0,0 +1,10 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head>
+<body onload="document.getElementById('form-basic-username').focus();">
+<!-- Username field is focused by js onload -->
+<form id="form-basic">
+  <input id="form-basic-username" name="username">
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-submit" type="submit">
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic.html b/toolkit/components/passwordmgr/test/browser/form_basic.html
new file mode 100644
index 0000000000..df2083a93c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simplest form with username and password fields. -->
+<form id="form-basic">
+  <input id="form-basic-username" name="username">
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-submit" type="submit">
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic_iframe.html b/toolkit/components/passwordmgr/test/browser/form_basic_iframe.html
new file mode 100644
index 0000000000..dd34739e6d
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic_iframe.html
@@ -0,0 +1,23 @@
+<!DOCTYPE html>
+<html>
+
+<head>
+    <meta charset="utf-8">
+</head>
+
+<body>
+    <!-- Form in an iframe -->
+    <iframe src="https://example.org/browser/toolkit/components/passwordmgr/test/browser/form_basic.html" id="test-iframe"></iframe>
+
+    <!-- Form in a fully sandboxed iframe -->
+    <iframe src="https://example.org/browser/toolkit/components/passwordmgr/test/browser/form_basic.html"
+            sandbox=""
+            id="test-iframe-sandbox"></iframe>
+
+    <!-- Form in an "allow-same-origin" sandboxed iframe -->
+    <iframe src="https://example.org/browser/toolkit/components/passwordmgr/test/browser/form_basic.html"
+            sandbox="allow-same-origin"
+            id="test-iframe-sandbox-same-origin"></iframe>
+</body>
+
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic_login.html b/toolkit/components/passwordmgr/test/browser/form_basic_login.html
new file mode 100644
index 0000000000..f63aca8b41
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic_login.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simplest login form with username and password fields. -->
+<form id="form-basic-login">
+  <input id="form-basic-username" name="username">
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-submit" type="submit" value="sign in">
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic_login_fields_with_max_length.html b/toolkit/components/passwordmgr/test/browser/form_basic_login_fields_with_max_length.html
new file mode 100644
index 0000000000..23c8efcc2a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic_login_fields_with_max_length.html
@@ -0,0 +1,19 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+    - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+  <!-- Simplest login form with username's maxlength attribute set -->
+  <form id="form-basic-max-password">
+    <input id="form-basic-username" name="username" maxlength="5">
+    <input id="form-basic-password" name="password" type="password" >
+    <input id="form-basic-submit" type="submit">
+  </form>
+
+  <!-- Simplest login form with password's maxlength attribute set -->
+  <form id="form-basic-max-username">
+    <input id="form-basic-username" name="username">
+    <input id="form-basic-password" name="password" type="password" maxlength="5">
+    <input id="form-basic-submit" type="submit">
+  </form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic_no_username.html b/toolkit/components/passwordmgr/test/browser/form_basic_no_username.html
new file mode 100644
index 0000000000..885fa9c11c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic_no_username.html
@@ -0,0 +1,11 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simplest form with just password field. -->
+<form id="form-basic">
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-submit" type="submit">
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic_password_autocomplete_new_password.html b/toolkit/components/passwordmgr/test/browser/form_basic_password_autocomplete_new_password.html
new file mode 100644
index 0000000000..53d821ddbb
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic_password_autocomplete_new_password.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+    - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+  <!-- Simplest login form with autocomplete="new-password" -->
+  <form id="form-basic-login">
+    <input id="form-basic-username" name="username">
+    <input id="form-basic-password" name="password" type="password" autocomplete="new-password">
+    <input id="form-basic-submit" type="submit">
+  </form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic_password_autocomplete_off.html b/toolkit/components/passwordmgr/test/browser/form_basic_password_autocomplete_off.html
new file mode 100644
index 0000000000..3ecf66d0cc
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic_password_autocomplete_off.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+    - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+  <!-- Simplest login form with autocomplete="off" -->
+  <form id="form-basic-login">
+    <input id="form-basic-username" name="username">
+    <input id="form-basic-password" name="password" type="password" autocomplete="off">
+    <input id="form-basic-submit" type="submit">
+  </form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic_prefilled_password.html b/toolkit/components/passwordmgr/test/browser/form_basic_prefilled_password.html
new file mode 100644
index 0000000000..7f2a8356f6
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic_prefilled_password.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+    - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+  <!-- Simplest login form with prefilled password field. -->
+  <form id="form-basic-login">
+    <input id="form-basic-username" name="username">
+    <input id="form-basic-password" name="password" type="password" value="filled-secret-password">
+    <input id="form-basic-submit" type="submit">
+  </form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic_prefilled_username.html b/toolkit/components/passwordmgr/test/browser/form_basic_prefilled_username.html
new file mode 100644
index 0000000000..23b1e16a98
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic_prefilled_username.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+  <!-- Simplest login form with prefilled username field. -->
+  <form id="form-basic-login">
+    <input id="form-basic-username" name="username" value="filled-username">
+    <input id="form-basic-password" name="password" type="password">
+    <input id="form-basic-submit" type="submit">
+  </form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic_signup.html b/toolkit/components/passwordmgr/test/browser/form_basic_signup.html
new file mode 100644
index 0000000000..a42a8cc609
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic_signup.html
@@ -0,0 +1,10 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+    - http://creativecommons.org/publicdomain/zero/1.0/ -->
+<form id="form-basic-signup">
+    <input id="form-basic-username" name="username">
+    <input id="form-basic-password" name="password" type="password" autocomplete="new-password">
+    <input id="form-basic-submit" type="submit" value="sign up">
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_basic_with_confirm_field.html b/toolkit/components/passwordmgr/test/browser/form_basic_with_confirm_field.html
new file mode 100644
index 0000000000..c638be4af7
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_basic_with_confirm_field.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simplest form with username, password and confirm password fields. -->
+<form id="form-basic">
+  <input id="form-basic-username" name="username">
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-confirm-password" name="confirm-password" type="password">
+  <input id="form-basic-submit" type="submit">
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_cross_origin_insecure_action.html b/toolkit/components/passwordmgr/test/browser/form_cross_origin_insecure_action.html
new file mode 100644
index 0000000000..8dde7ceb63
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_cross_origin_insecure_action.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simplest form with username and password fields. -->
+<form id="form-basic" action="http://example.org/custom_action.html">
+  <input id="form-basic-username" name="username">
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-submit" type="submit">
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_cross_origin_secure_action.html b/toolkit/components/passwordmgr/test/browser/form_cross_origin_secure_action.html
new file mode 100644
index 0000000000..2d95419549
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_cross_origin_secure_action.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simplest form with username and password fields. -->
+<form id="form-basic" action="https://example.org/custom_action.html">
+  <input id="form-basic-username" name="username">
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-submit" type="submit">
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_crossframe.html b/toolkit/components/passwordmgr/test/browser/form_crossframe.html
new file mode 100644
index 0000000000..fbb759c632
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_crossframe.html
@@ -0,0 +1,13 @@
+<html><body>
+
+<button onclick="window.location = 'about:blank'">Next</button>
+<iframe src="https://test2.example.org:443/browser/toolkit/components/passwordmgr/test/browser/form_crossframe_inner.html"
+        width="300" height="300"></iframe>
+<form id="outer-form" action="formsubmit.sjs">
+  <input id="outer-username" name="outer-username">
+  <input id="outer-password" name="outer-password" type="password">
+  <input id="outer-submit" type="submit">
+  <button id="outer-gobutton" onclick="this.location = 'about:blank'">Go</button>
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_crossframe_inner.html b/toolkit/components/passwordmgr/test/browser/form_crossframe_inner.html
new file mode 100644
index 0000000000..9a919993bf
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_crossframe_inner.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Form for use inside a frame. -->
+<form id="inner-form" action="formsubmit.sjs">
+  <input id="inner-username" name="username">
+  <input id="inner-password" name="password" type="password">
+  <input id="inner-submit" type="submit">
+</form>
+<button id="inner-gobutton" onclick="document.location = 'about:blank'">Go</button>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_crossframe_no_outer_login_form.html b/toolkit/components/passwordmgr/test/browser/form_crossframe_no_outer_login_form.html
new file mode 100644
index 0000000000..e98f43f48d
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_crossframe_no_outer_login_form.html
@@ -0,0 +1,8 @@
+<!DOCTYPE html><html><head><meta charset=`utf-8`></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+    - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+    <!-- Crossframe with login form -->
+    <iframe src="https://test2.example.org:443/browser/toolkit/components/passwordmgr/test/browser/form_crossframe_inner.html"
+        width="600" height="600"></iframe>
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_disabled_readonly_passwordField.html b/toolkit/components/passwordmgr/test/browser/form_disabled_readonly_passwordField.html
new file mode 100644
index 0000000000..4e47d9790d
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_disabled_readonly_passwordField.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html><body>
+    <form id="login_form_disabled_password">
+        <input type="text" name="username" autocomplete="username">
+        <input type="password" name="password" autocomplete="password" disabled>
+        <button type="submit">Log in</button>
+    </form>
+    <form id="login_form_readonly_password">
+        <input type="text" name="username" autocomplete="username">
+        <input type="password" name="password" autocomplete="password" readonly>
+        <button type="submit">Log in</button>
+    </form>
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_expanded.html b/toolkit/components/passwordmgr/test/browser/form_expanded.html
new file mode 100644
index 0000000000..567a373f5b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_expanded.html
@@ -0,0 +1,16 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+    - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Expanded page containing a form + several unrelated elements -->
+
+<form id="form-basic">
+  <input id="form-expanded-search">
+  <input id="form-expanded-username" name="username">
+  <input id="form-expanded-password" name="password" type="password">
+  <input id="form-expanded-submit" type="submit">
+  <input id="form-expanded-captcha">
+</form>
+<input id="form-expanded-non-form-input">
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_multipage.html b/toolkit/components/passwordmgr/test/browser/form_multipage.html
new file mode 100644
index 0000000000..908457fd50
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_multipage.html
@@ -0,0 +1,32 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Form with a username-only field. -->
+<form id="form-basic">
+  <input id="form-basic-username" type="text" name="username" autocomplete="username">
+  <input id="form-basic-submit" type="submit">
+</form>
+
+<script>
+  const form = document.getElementById( "form-basic" );
+  form.addEventListener( "submit", function onFormSubmit(event) {
+    event.preventDefault()
+    document.getElementById("form-basic").remove();
+
+    // Create the password-only form after the username-only form is submitted.
+    var form = document.createElement("form");
+    form.id = "form-basic";
+    var password = document.createElement("input");
+    password.id = "form-basic-password";
+    password.type = "password";
+    form.appendChild(password);
+    var submit = document.createElement("input");
+    submit.id = "form-basic-submit";
+    submit.type = "submit";
+    form.appendChild(submit);
+    document.body.appendChild(form);
+  });
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_multiple_passwords.html b/toolkit/components/passwordmgr/test/browser/form_multiple_passwords.html
new file mode 100644
index 0000000000..303f88933e
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_multiple_passwords.html
@@ -0,0 +1,16 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+    - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+  <!-- Simplest form with password field count over threshold -->
+  <form id="form-basic-login">
+    <input id="form-basic-password" name="password" type="password">
+    <input id="form-basic-password" name="password" type="password">
+    <input id="form-basic-password" name="password" type="password">
+    <input id="form-basic-password" name="password" type="password">
+    <input id="form-basic-password" name="password" type="password">
+    <input id="form-basic-password" name="password" type="password">
+    <input id="form-basic-submit" type="submit">
+  </form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_password_change.html b/toolkit/components/passwordmgr/test/browser/form_password_change.html
new file mode 100644
index 0000000000..279de622f2
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_password_change.html
@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for Login Manager notifications w/ new password</title>
+</head>
+<body>
+<h2>Test for Login Manager notifications w/ new password</h2>
+
+<form id="form" action="formsubmit.sjs">
+  <input id="pass" name="pass" type="password">
+  <input id="newpass" name="newpass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_same_origin_action.html b/toolkit/components/passwordmgr/test/browser/form_same_origin_action.html
new file mode 100644
index 0000000000..8f0c9a14e2
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_same_origin_action.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simplest form with username and password fields. -->
+<form id="form-basic" action="./custom_action.html">
+  <input id="form-basic-username" name="username">
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-submit" type="submit">
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_signup_detection.html b/toolkit/components/passwordmgr/test/browser/form_signup_detection.html
new file mode 100644
index 0000000000..96cf2967de
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_signup_detection.html
@@ -0,0 +1,34 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+</head>
+<body>
+    <h1>Sign up</h1>
+    <form id="obvious-signup-form">
+        <label for="obvious-signup-email">Email</label>
+        <input id="obvious-signup-email" type="email">
+        <label for="obvious-signup-username">Username</label>
+        <input id="obvious-signup-username">
+        <label for="obvious-signup-password">Password</label>
+        <input id="obvious-signup-password" type="password" autocomplete="new-password">
+        <input id= "obvious-signup-privacyPolicy" type="checkbox">
+        <label for="obvious-signup-privacyPolicy">I have read and agree to the privacy policy.</label>
+        <input id="obvious-signup-submit" type="submit" value="Sign up">
+    </form>
+    <h1>Login</h1>
+    <form id="obvious-login-form">
+      <label for="obvious-login-username">Username</label>
+      <input id="obvious-login-username">
+      <label for="obvious-login-password">Password</label>
+      <input id="obvious-login-password" type="password" autocomplete="current-password">
+      <a>Password forgotten?</a>
+      <input id= "obvious-login-rememberMe" type="checkbox">
+      <label for="obvious-login-rememberMe">Remember me</label>
+      <input id="obvious-login-submit" type="submit" value="Login">
+    </form>
+    <h1>Standalone input</h1>
+    <label for="standalone-username">Username</label>
+    <input id="standalone-username">
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_unmasked_password_after_pageload.html b/toolkit/components/passwordmgr/test/browser/form_unmasked_password_after_pageload.html
new file mode 100644
index 0000000000..7a5acd4fd1
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_unmasked_password_after_pageload.html
@@ -0,0 +1,16 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head>
+<!-- Any copyright is dedicated to the Public Domain.
+    - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+  <!-- Unmasks the password field after page load -->
+  <body onload="document.getElementById(`form-basic-password`).type = ``">
+
+    <!-- Simplest login form with username and password fields. -->
+    <form id="form-basic-login">
+      <input id="form-basic-username" name="username">
+      <input id="form-basic-password" name="password" type="password">
+      <input id="form-basic-submit" type="submit" value="sign in">
+    </form>
+
+  </body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/form_username_only.html b/toolkit/components/passwordmgr/test/browser/form_username_only.html
new file mode 100644
index 0000000000..d3bb2844b1
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/form_username_only.html
@@ -0,0 +1,11 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+    - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+  <!-- Simplest username-only form. -->
+  <form id="form-username-only">
+    <input id="form-basic-username" name="username" type="text">
+    <input id="form-basic-submit" type="submit">
+  </form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/formless_basic.html b/toolkit/components/passwordmgr/test/browser/formless_basic.html
new file mode 100644
index 0000000000..17455df96e
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/formless_basic.html
@@ -0,0 +1,18 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+
+<!-- Simplest form with username and password fields. -->
+  <input id="form-basic-username" name="username">
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-submit" type="submit">
+
+  <button id="add">Add input[type=password]</button>
+
+  <script>
+    document.getElementById("add").addEventListener("click", function() {
+      var node = document.createElement("input");
+      node.setAttribute("type", "password");
+      document.querySelector("body").appendChild(node);
+    });
+  </script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/head.js b/toolkit/components/passwordmgr/test/browser/head.js
new file mode 100644
index 0000000000..a84a56f2e2
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/head.js
@@ -0,0 +1,965 @@
+const DIRECTORY_PATH = "/browser/toolkit/components/passwordmgr/test/browser/";
+
+var { LoginTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/LoginTestUtils.sys.mjs"
+);
+
+const { TelemetryTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/TelemetryTestUtils.sys.mjs"
+);
+const { PromptTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/PromptTestUtils.sys.mjs"
+);
+
+add_setup(async function common_initialize() {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["signon.rememberSignons", true],
+      ["signon.testOnlyUserHasInteractedByPrefValue", true],
+      ["signon.testOnlyUserHasInteractedWithDocument", true],
+      ["toolkit.telemetry.ipcBatchTimeout", 0],
+    ],
+  });
+  if (LoginHelper.relatedRealmsEnabled) {
+    await LoginTestUtils.remoteSettings.setupWebsitesWithSharedCredentials();
+    registerCleanupFunction(async function () {
+      await LoginTestUtils.remoteSettings.cleanWebsitesWithSharedCredentials();
+    });
+  }
+});
+
+registerCleanupFunction(
+  async function cleanup_removeAllLoginsAndResetRecipes() {
+    await SpecialPowers.popPrefEnv();
+
+    LoginTestUtils.clearData();
+    LoginTestUtils.resetGeneratedPasswordsCache();
+    clearHttpAuths();
+    Services.telemetry.clearEvents();
+
+    let recipeParent = LoginTestUtils.recipes.getRecipeParent();
+    if (!recipeParent) {
+      // No need to reset the recipes if the recipe module wasn't even loaded.
+      return;
+    }
+    await recipeParent.then(recipeParentResult => recipeParentResult.reset());
+
+    await cleanupDoorhanger();
+    await cleanupPasswordNotifications();
+    await closePopup(document.getElementById("contentAreaContextMenu"));
+    await closePopup(document.getElementById("PopupAutoComplete"));
+  }
+);
+
+/**
+ * Compared logins in storage to expected values
+ *
+ * @param {array} expectedLogins
+ *        An array of expected login properties
+ * @return {nsILoginInfo[]} - All saved logins sorted by timeCreated
+ */
+async function verifyLogins(expectedLogins = []) {
+  let allLogins = await Services.logins.getAllLogins();
+  allLogins.sort((a, b) => a.timeCreated > b.timeCreated);
+  Assert.equal(
+    allLogins.length,
+    expectedLogins.length,
+    "Check actual number of logins matches the number of provided expected property-sets"
+  );
+  for (let i = 0; i < expectedLogins.length; i++) {
+    // if the test doesn't care about comparing properties for this login, just pass false/null.
+    let expected = expectedLogins[i];
+    if (expected) {
+      let login = allLogins[i];
+      if (typeof expected.timesUsed !== "undefined") {
+        Assert.equal(login.timesUsed, expected.timesUsed, "Check timesUsed");
+      }
+      if (typeof expected.passwordLength !== "undefined") {
+        Assert.equal(
+          login.password.length,
+          expected.passwordLength,
+          "Check passwordLength"
+        );
+      }
+      if (typeof expected.username !== "undefined") {
+        Assert.equal(login.username, expected.username, "Check username");
+      }
+      if (typeof expected.password !== "undefined") {
+        Assert.equal(login.password, expected.password, "Check password");
+      }
+      if (typeof expected.usedSince !== "undefined") {
+        Assert.ok(
+          login.timeLastUsed > expected.usedSince,
+          "Check timeLastUsed"
+        );
+      }
+      if (typeof expected.passwordChangedSince !== "undefined") {
+        Assert.ok(
+          login.timePasswordChanged > expected.passwordChangedSince,
+          "Check timePasswordChanged"
+        );
+      }
+      if (typeof expected.timeCreated !== "undefined") {
+        Assert.equal(
+          login.timeCreated,
+          expected.timeCreated,
+          "Check timeCreated"
+        );
+      }
+    }
+  }
+  return allLogins;
+}
+
+/**
+ * Submit the content form and return a promise resolving to the username and
+ * password values echoed out in the response
+ *
+ * @param {Object} [browser] - browser with the form
+ * @param {String = ""} formAction - Optional url to set the form's action to before submitting
+ * @param {Object = null} selectorValues - Optional object with field values to set before form submission
+ * @param {Object = null} responseSelectors - Optional object with selectors to find the username and password in the response
+ */
+async function submitFormAndGetResults(
+  browser,
+  formAction = "",
+  selectorValues,
+  responseSelectors
+) {
+  async function contentSubmitForm([contentFormAction, contentSelectorValues]) {
+    const { WrapPrivileged } = ChromeUtils.importESModule(
+      "resource://testing-common/WrapPrivileged.sys.mjs"
+    );
+    let doc = content.document;
+    let form = doc.querySelector("form");
+    if (contentFormAction) {
+      form.action = contentFormAction;
+    }
+    for (let [sel, value] of Object.entries(contentSelectorValues)) {
+      try {
+        let field = doc.querySelector(sel);
+        let gotInput = ContentTaskUtils.waitForEvent(
+          field,
+          "input",
+          "Got input event on " + sel
+        );
+        // we don't get an input event if the new value == the old
+        field.value = "###";
+        WrapPrivileged.wrap(field, this).setUserInput(value);
+        await gotInput;
+      } catch (ex) {
+        throw new Error(
+          `submitForm: Couldn't set value of field at: ${sel}: ${ex.message}`
+        );
+      }
+    }
+    form.submit();
+  }
+
+  let loadPromise = BrowserTestUtils.browserLoaded(browser);
+  await SpecialPowers.spawn(
+    browser,
+    [[formAction, selectorValues]],
+    contentSubmitForm
+  );
+  await loadPromise;
+
+  let result = await getFormSubmitResponseResult(
+    browser,
+    formAction,
+    responseSelectors
+  );
+  return result;
+}
+
+/**
+ * Wait for a given result page to load and return a promise resolving to an object with the parsed-out
+ * username/password values from the response
+ *
+ * @param {Object} [browser] - browser which is loading this page
+ * @param {String} resultURL - the path or filename to look for in the content.location
+ * @param {Object = null} - Optional object with selectors to find the username and password in the response
+ */
+async function getFormSubmitResponseResult(
+  browser,
+  resultURL = "/formsubmit.sjs",
+  { username = "#user", password = "#pass" } = {}
+) {
+  // default selectors are for the response page produced by formsubmit.sjs
+  let fieldValues = await ContentTask.spawn(
+    browser,
+    {
+      resultURL,
+      usernameSelector: username,
+      passwordSelector: password,
+    },
+    async function ({ resultURL, usernameSelector, passwordSelector }) {
+      await ContentTaskUtils.waitForCondition(() => {
+        return (
+          content.location.pathname.endsWith(resultURL) &&
+          content.document.readyState == "complete"
+        );
+      }, `Wait for form submission load (${resultURL})`);
+      let username =
+        content.document.querySelector(usernameSelector).textContent;
+      // Bug 1686071: Since generated passwords can have special characters in them,
+      // we need to unescape the characters. These special characters are automatically escaped
+      // when we submit a form in `submitFormAndGetResults`.
+      // Otherwise certain tests will intermittently fail when these special characters are present in the passwords.
+      let password = unescape(
+        content.document.querySelector(passwordSelector).textContent
+      );
+      return {
+        username,
+        password,
+      };
+    }
+  );
+  return fieldValues;
+}
+
+/**
+ * Loads a test page in `DIRECTORY_URL` which automatically submits to formsubmit.sjs and returns a
+ * promise resolving with the field values when the optional `aTaskFn` is done.
+ *
+ * @param {String} aPageFile - test page file name which auto-submits to formsubmit.sjs
+ * @param {Function} aTaskFn - task which can be run before the tab closes.
+ * @param {String} [aOrigin="https://example.com"] - origin of the server to use
+ *                                                  to load `aPageFile`.
+ */
+function testSubmittingLoginForm(
+  aPageFile,
+  aTaskFn,
+  aOrigin = "https://example.com"
+) {
+  return BrowserTestUtils.withNewTab(
+    {
+      gBrowser,
+      url: aOrigin + DIRECTORY_PATH + aPageFile,
+    },
+    async function (browser) {
+      Assert.ok(true, "loaded " + aPageFile);
+      let fieldValues = await getFormSubmitResponseResult(
+        browser,
+        "/formsubmit.sjs"
+      );
+      Assert.ok(true, "form submission loaded");
+      if (aTaskFn) {
+        await aTaskFn(fieldValues, browser);
+      }
+      return fieldValues;
+    }
+  );
+}
+/**
+ * Loads a test page in `DIRECTORY_URL` which automatically submits to formsubmit.sjs and returns a
+ * promise resolving with the field values when the optional `aTaskFn` is done.
+ *
+ * @param {String} aPageFile - test page file name which auto-submits to formsubmit.sjs
+ * @param {Function} aTaskFn - task which can be run before the tab closes.
+ * @param {String} [aOrigin="http://example.com"] - origin of the server to use
+ *                                                  to load `aPageFile`.
+ */
+function testSubmittingLoginFormHTTP(
+  aPageFile,
+  aTaskFn,
+  aOrigin = "http://example.com"
+) {
+  return testSubmittingLoginForm(aPageFile, aTaskFn, aOrigin);
+}
+
+async function checkOnlyLoginWasUsedTwice({ justChanged }) {
+  // Check to make sure we updated the timestamps and use count on the
+  // existing login that was submitted for the test.
+  let logins = await Services.logins.getAllLogins();
+  Assert.equal(logins.length, 1, "Should only have 1 login");
+  Assert.ok(logins[0] instanceof Ci.nsILoginMetaInfo, "metainfo QI");
+  Assert.equal(
+    logins[0].timesUsed,
+    2,
+    "check .timesUsed for existing login submission"
+  );
+  Assert.ok(
+    logins[0].timeCreated < logins[0].timeLastUsed,
+    "timeLastUsed bumped"
+  );
+  if (justChanged) {
+    Assert.equal(
+      logins[0].timeLastUsed,
+      logins[0].timePasswordChanged,
+      "timeLastUsed == timePasswordChanged"
+    );
+  } else {
+    Assert.equal(
+      logins[0].timeCreated,
+      logins[0].timePasswordChanged,
+      "timeChanged not updated"
+    );
+  }
+}
+
+function clearHttpAuths() {
+  let authMgr = Cc["@mozilla.org/network/http-auth-manager;1"].getService(
+    Ci.nsIHttpAuthManager
+  );
+  authMgr.clearAll();
+}
+
+// Begin popup notification (doorhanger) functions //
+
+const REMEMBER_BUTTON = "button";
+const NEVER_MENUITEM = 0;
+
+const CHANGE_BUTTON = "button";
+const DONT_CHANGE_BUTTON = "secondaryButton";
+const REMOVE_LOGIN_MENUITEM = 0;
+
+/**
+ * Checks if we have a password capture popup notification
+ * of the right type and with the right label.
+ *
+ * @param {String} aKind The desired `passwordNotificationType` ("any" for any type)
+ * @param {Object} [popupNotifications = PopupNotifications]
+ * @param {Object} [browser = null] Optional browser whose notifications should be searched.
+ * @return the found password popup notification.
+ */
+function getCaptureDoorhanger(
+  aKind,
+  popupNotifications = PopupNotifications,
+  browser = null
+) {
+  Assert.ok(true, "Looking for " + aKind + " popup notification");
+  let notification = popupNotifications.getNotification("password", browser);
+  if (!aKind) {
+    throw new Error(
+      "getCaptureDoorhanger needs aKind to be a non-empty string"
+    );
+  }
+  if (aKind !== "any" && notification) {
+    Assert.equal(
+      notification.options.passwordNotificationType,
+      aKind,
+      "Notification type matches."
+    );
+    if (aKind == "password-change") {
+      Assert.equal(
+        notification.mainAction.label,
+        "Update",
+        "Main action label matches update doorhanger."
+      );
+    } else if (aKind == "password-save") {
+      Assert.equal(
+        notification.mainAction.label,
+        "Save",
+        "Main action label matches save doorhanger."
+      );
+    }
+  }
+  return notification;
+}
+
+async function getCaptureDoorhangerThatMayOpen(
+  aKind,
+  popupNotifications = PopupNotifications,
+  browser = null
+) {
+  let notif = getCaptureDoorhanger(aKind, popupNotifications, browser);
+  if (notif && !notif.dismissed) {
+    if (popupNotifications.panel.state !== "open") {
+      await BrowserTestUtils.waitForEvent(
+        popupNotifications.panel,
+        "popupshown"
+      );
+    }
+  }
+  return notif;
+}
+
+async function waitForDoorhanger(browser, type) {
+  let notif;
+  await TestUtils.waitForCondition(() => {
+    notif = PopupNotifications.getNotification("password", browser);
+    if (notif && type !== "any") {
+      return (
+        notif.options.passwordNotificationType == type &&
+        notif.anchorElement &&
+        BrowserTestUtils.isVisible(notif.anchorElement)
+      );
+    }
+    return notif;
+  }, `Waiting for a ${type} notification`);
+  return notif;
+}
+
+async function hideDoorhangerPopup() {
+  info("hideDoorhangerPopup");
+  if (!PopupNotifications.isPanelOpen) {
+    return;
+  }
+  let { panel } = PopupNotifications;
+  let promiseHidden = BrowserTestUtils.waitForEvent(panel, "popuphidden");
+  panel.hidePopup();
+  await promiseHidden;
+  info("got popuphidden from notification panel");
+}
+
+function getDoorhangerButton(aPopup, aButtonIndex) {
+  let notifications = aPopup.owner.panel.children;
+  Assert.ok(!!notifications.length, "at least one notification displayed");
+  Assert.ok(true, notifications.length + " notification(s)");
+  let notification = notifications[0];
+
+  if (aButtonIndex == "button") {
+    return notification.button;
+  } else if (aButtonIndex == "secondaryButton") {
+    return notification.secondaryButton;
+  }
+  return notification.menupopup.querySelectorAll("menuitem")[aButtonIndex];
+}
+
+/**
+ * Clicks the specified popup notification button.
+ *
+ * @param {Element} aPopup Popup Notification element
+ * @param {Number} aButtonIndex Number indicating which button to click.
+ *                              See the constants in this file.
+ */
+function clickDoorhangerButton(aPopup, aButtonIndex) {
+  Assert.ok(true, "Looking for action at index " + aButtonIndex);
+
+  let button = getDoorhangerButton(aPopup, aButtonIndex);
+  if (aButtonIndex == "button") {
+    Assert.ok(true, "Triggering main action");
+  } else if (aButtonIndex == "secondaryButton") {
+    Assert.ok(true, "Triggering secondary action");
+  } else {
+    Assert.ok(true, "Triggering menuitem # " + aButtonIndex);
+  }
+  button.doCommand();
+}
+
+async function cleanupDoorhanger(notif) {
+  let PN = notif ? notif.owner : PopupNotifications;
+  if (notif) {
+    notif.remove();
+  }
+  let promiseHidden = PN.isPanelOpen
+    ? BrowserTestUtils.waitForEvent(PN.panel, "popuphidden")
+    : Promise.resolve();
+  PN.panel.hidePopup();
+  await promiseHidden;
+}
+
+async function cleanupPasswordNotifications(
+  popupNotifications = PopupNotifications
+) {
+  let notif;
+  while ((notif = popupNotifications.getNotification("password"))) {
+    notif.remove();
+  }
+}
+
+async function clearMessageCache(browser) {
+  await SpecialPowers.spawn(browser, [], async () => {
+    const { LoginManagerChild } = ChromeUtils.importESModule(
+      "resource://gre/modules/LoginManagerChild.sys.mjs"
+    );
+    let docState = LoginManagerChild.forWindow(content).stateForDocument(
+      content.document
+    );
+    docState.lastSubmittedValuesByRootElement = new content.WeakMap();
+  });
+}
+
+/**
+ * Checks the doorhanger's username and password.
+ *
+ * @param {String} username The username.
+ * @param {String} password The password.
+ */
+async function checkDoorhangerUsernamePassword(username, password) {
+  await BrowserTestUtils.waitForCondition(() => {
+    return (
+      document.getElementById("password-notification-username").value ==
+        username &&
+      document.getElementById("password-notification-password").value ==
+        password
+    );
+  }, "Wait for nsLoginManagerPrompter writeDataToUI() to update to the correct username/password values");
+}
+
+/**
+ * Change the doorhanger's username and password input values.
+ *
+ * @param {object} newValues
+ *        named values to update
+ * @param {string} [newValues.password = undefined]
+ *        An optional string value to replace whatever is in the password field
+ * @param {string} [newValues.username = undefined]
+ *        An optional string value to replace whatever is in the username field
+ * @param {Object} [popupNotifications = PopupNotifications]
+ */
+async function updateDoorhangerInputValues(
+  newValues,
+  popupNotifications = PopupNotifications
+) {
+  let { panel } = popupNotifications;
+  if (popupNotifications.panel.state !== "open") {
+    await BrowserTestUtils.waitForEvent(popupNotifications.panel, "popupshown");
+  }
+  Assert.equal(panel.state, "open", "Check the doorhanger is already open");
+
+  let notifElem = panel.childNodes[0];
+
+  // Note: setUserInput does not reliably dispatch input events from chrome elements?
+  async function setInputValue(target, value) {
+    info(`setInputValue: on target: ${target.id}, value: ${value}`);
+    target.focus();
+    target.select();
+    info(
+      `setInputValue: current value: '${target.value}', setting new value '${value}'`
+    );
+    await EventUtils.synthesizeKey("KEY_Backspace");
+    await EventUtils.sendString(value);
+    await EventUtils.synthesizeKey("KEY_Tab");
+    return Promise.resolve();
+  }
+
+  let passwordField = notifElem.querySelector(
+    "#password-notification-password"
+  );
+  let usernameField = notifElem.querySelector(
+    "#password-notification-username"
+  );
+
+  if (typeof newValues.password !== "undefined") {
+    if (passwordField.value !== newValues.password) {
+      await setInputValue(passwordField, newValues.password);
+    }
+  }
+  if (typeof newValues.username !== "undefined") {
+    if (usernameField.value !== newValues.username) {
+      await setInputValue(usernameField, newValues.username);
+    }
+  }
+}
+
+/**
+ * Open doorhanger autocomplete popup and select a username value.
+ *
+ * @param {string} text the text value of the username that should be selected.
+ *                 Noop if `text` is falsy.
+ */
+async function selectDoorhangerUsername(text) {
+  await _selectDoorhanger(
+    text,
+    "#password-notification-username",
+    "#password-notification-username-dropmarker"
+  );
+}
+
+/**
+ * Open doorhanger autocomplete popup and select a password value.
+ *
+ * @param {string} text the text value of the password that should be selected.
+ *                 Noop if `text` is falsy.
+ */
+async function selectDoorhangerPassword(text) {
+  await _selectDoorhanger(
+    text,
+    "#password-notification-password",
+    "#password-notification-password-dropmarker"
+  );
+}
+
+async function _selectDoorhanger(text, inputSelector, dropmarkerSelector) {
+  if (!text) {
+    return;
+  }
+
+  info("Opening doorhanger suggestion popup");
+
+  let doorhangerPopup = document.getElementById("password-notification");
+  let dropmarker = doorhangerPopup.querySelector(dropmarkerSelector);
+
+  let autocompletePopup = document.getElementById("PopupAutoComplete");
+  let popupShown = BrowserTestUtils.waitForEvent(
+    autocompletePopup,
+    "popupshown"
+  );
+  // the dropmarker gets un-hidden async when looking up username suggestions
+  await TestUtils.waitForCondition(() => !dropmarker.hidden);
+
+  EventUtils.synthesizeMouseAtCenter(dropmarker, {});
+
+  await popupShown;
+
+  let suggestions = [
+    ...document
+      .getElementById("PopupAutoComplete")
+      .getElementsByTagName("richlistitem"),
+  ].filter(richlistitem => !richlistitem.collapsed);
+
+  let suggestionText = suggestions.map(
+    richlistitem => richlistitem.querySelector(".ac-title-text").innerHTML
+  );
+
+  let targetIndex = suggestionText.indexOf(text);
+  Assert.ok(targetIndex != -1, "Suggestions include expected text");
+
+  let promiseHidden = BrowserTestUtils.waitForEvent(
+    autocompletePopup,
+    "popuphidden"
+  );
+
+  info("Selecting doorhanger suggestion");
+
+  EventUtils.synthesizeMouseAtCenter(suggestions[targetIndex], {});
+
+  await promiseHidden;
+}
+
+// End popup notification (doorhanger) functions //
+
+async function openPasswordManager(openingFunc, waitForFilter) {
+  info("waiting for new tab to open");
+  let tabPromise = BrowserTestUtils.waitForNewTab(
+    gBrowser,
+    url => url.includes("about:logins") && !url.includes("entryPoint="),
+    true
+  );
+  await openingFunc();
+  let tab = await tabPromise;
+  Assert.ok(tab, "got password management tab");
+  let filterValue;
+  if (waitForFilter) {
+    filterValue = await SpecialPowers.spawn(tab.linkedBrowser, [], async () => {
+      let loginFilter = Cu.waiveXrays(
+        content.document
+          .querySelector("login-list")
+          .shadowRoot.querySelector("login-filter")
+      );
+      await ContentTaskUtils.waitForCondition(
+        () => !!loginFilter.value,
+        "wait for login-filter to have a value"
+      );
+      return loginFilter.value;
+    });
+  }
+  return {
+    filterValue,
+    close() {
+      BrowserTestUtils.removeTab(tab);
+    },
+  };
+}
+
+// Autocomplete popup related functions //
+
+async function openACPopup(
+  popup,
+  browser,
+  inputSelector,
+  iframeBrowsingContext = null
+) {
+  let promiseShown = BrowserTestUtils.waitForEvent(popup, "popupshown");
+
+  await SimpleTest.promiseFocus(browser);
+  info("content window focused");
+
+  // Focus the username field to open the popup.
+  let target = iframeBrowsingContext || browser;
+  await SpecialPowers.spawn(
+    target,
+    [[inputSelector]],
+    function openAutocomplete(sel) {
+      content.document.querySelector(sel).focus();
+    }
+  );
+
+  let shown = await promiseShown;
+  Assert.ok(shown, "autocomplete popup shown");
+  return shown;
+}
+
+async function closePopup(popup) {
+  if (popup.state == "closed") {
+    await Promise.resolve();
+  } else {
+    let promiseHidden = BrowserTestUtils.waitForEvent(popup, "popuphidden");
+    popup.hidePopup();
+    await promiseHidden;
+  }
+}
+
+async function fillGeneratedPasswordFromOpenACPopup(
+  browser,
+  passwordInputSelector
+) {
+  let popup = browser.ownerDocument.getElementById("PopupAutoComplete");
+  let item;
+
+  await new Promise(requestAnimationFrame);
+  await TestUtils.waitForCondition(() => {
+    item = popup.querySelector(`[originaltype="generatedPassword"]`);
+    return item && !EventUtils.isHidden(item);
+  }, "Waiting for item to become visible");
+
+  let inputEventPromise = ContentTask.spawn(
+    browser,
+    [passwordInputSelector],
+    async function waitForInput(inputSelector) {
+      let passwordInput = content.document.querySelector(inputSelector);
+      await ContentTaskUtils.waitForEvent(
+        passwordInput,
+        "input",
+        "Password input value changed"
+      );
+    }
+  );
+
+  let passwordGeneratedPromise = listenForTestNotification(
+    "PasswordEditedOrGenerated"
+  );
+
+  info("Clicking the generated password AC item");
+  EventUtils.synthesizeMouseAtCenter(item, {});
+  info("Waiting for the content input value to change");
+  await inputEventPromise;
+  info("Waiting for the passwordGeneratedPromise");
+  await passwordGeneratedPromise;
+}
+
+// Contextmenu functions //
+
+/**
+ * Synthesize mouse clicks to open the password manager context menu popup
+ * for a target password input element.
+ *
+ * assertCallback should return true if we should continue or else false.
+ */
+async function openPasswordContextMenu(
+  browser,
+  input,
+  assertCallback = null,
+  browsingContext = null,
+  openFillMenu = null
+) {
+  const doc = browser.ownerDocument;
+  const CONTEXT_MENU = doc.getElementById("contentAreaContextMenu");
+  const POPUP_HEADER = doc.getElementById("fill-login");
+  const LOGIN_POPUP = doc.getElementById("fill-login-popup");
+
+  if (!browsingContext) {
+    browsingContext = browser.browsingContext;
+  }
+
+  let contextMenuShownPromise = BrowserTestUtils.waitForEvent(
+    CONTEXT_MENU,
+    "popupshown"
+  );
+
+  // Synthesize a right mouse click over the password input element, we have to trigger
+  // both events because formfill code relies on this event happening before the contextmenu
+  // (which it does for real user input) in order to not show the password autocomplete.
+  let eventDetails = { type: "mousedown", button: 2 };
+  await BrowserTestUtils.synthesizeMouseAtCenter(
+    input,
+    eventDetails,
+    browsingContext
+  );
+  // Synthesize a contextmenu event to actually open the context menu.
+  eventDetails = { type: "contextmenu", button: 2 };
+  await BrowserTestUtils.synthesizeMouseAtCenter(
+    input,
+    eventDetails,
+    browsingContext
+  );
+
+  await contextMenuShownPromise;
+
+  if (assertCallback) {
+    let shouldContinue = await assertCallback();
+    if (!shouldContinue) {
+      return;
+    }
+  }
+
+  if (openFillMenu) {
+    // Open the fill login menu.
+    let popupShownPromise = BrowserTestUtils.waitForEvent(
+      LOGIN_POPUP,
+      "popupshown"
+    );
+    POPUP_HEADER.openMenu(true);
+    await popupShownPromise;
+  }
+}
+
+/**
+ * Listen for the login manager test notification specified by
+ * expectedMessage. Possible messages:
+ *   FormProcessed - a form was processed after page load.
+ *   FormSubmit - a form was just submitted.
+ *   PasswordEditedOrGenerated - a password was filled in or modified.
+ *
+ * The count is the number of that messages to wait for. This should
+ * typically be used when waiting for the FormProcessed message for a page
+ * that has subframes to ensure all have been handled.
+ *
+ * Returns a promise that will passed additional data specific to the message.
+ */
+function listenForTestNotification(expectedMessage, count = 1) {
+  return new Promise(resolve => {
+    LoginManagerParent.setListenerForTests((msg, data) => {
+      if (msg == expectedMessage && --count == 0) {
+        LoginManagerParent.setListenerForTests(null);
+        info("listenForTestNotification, resolving for message: " + msg);
+        resolve(data);
+      }
+    });
+  });
+}
+
+/**
+ * Use the contextmenu to fill a field with a generated password
+ */
+async function doFillGeneratedPasswordContextMenuItem(browser, passwordInput) {
+  await SimpleTest.promiseFocus(browser);
+  await openPasswordContextMenu(browser, passwordInput);
+
+  let generatedPasswordItem = document.getElementById(
+    "fill-login-generated-password"
+  );
+  let generatedPasswordSeparator = document.getElementById(
+    "passwordmgr-items-separator"
+  );
+
+  Assert.ok(
+    BrowserTestUtils.isVisible(generatedPasswordItem),
+    "generated password item is visible"
+  );
+  Assert.ok(
+    BrowserTestUtils.isVisible(generatedPasswordSeparator),
+    "separator is visible"
+  );
+
+  let popup = document.getElementById("PopupAutoComplete");
+  Assert.ok(popup, "Got popup");
+  let promiseShown = BrowserTestUtils.waitForEvent(popup, "popupshown");
+
+  await new Promise(resolve => {
+    SimpleTest.executeSoon(resolve);
+  });
+
+  let contextMenu = document.getElementById("contentAreaContextMenu");
+  contextMenu.activateItem(generatedPasswordItem);
+
+  await promiseShown;
+  await fillGeneratedPasswordFromOpenACPopup(browser, passwordInput);
+}
+
+// Content form helpers
+async function changeContentFormValues(
+  browser,
+  selectorValues,
+  shouldBlur = true
+) {
+  for (let [sel, value] of Object.entries(selectorValues)) {
+    info("changeContentFormValues, update: " + sel + ", to: " + value);
+    await changeContentInputValue(browser, sel, value, shouldBlur);
+    await TestUtils.waitForTick();
+  }
+}
+
+async function changeContentInputValue(
+  browser,
+  selector,
+  str,
+  shouldBlur = true
+) {
+  await SimpleTest.promiseFocus(browser.ownerGlobal);
+  let oldValue = await ContentTask.spawn(browser, [selector], function (sel) {
+    return content.document.querySelector(sel).value;
+  });
+
+  if (str === oldValue) {
+    info("no change needed to value of " + selector + ": " + oldValue);
+    return;
+  }
+  info(`changeContentInputValue: from "${oldValue}" to "${str}"`);
+  await ContentTask.spawn(
+    browser,
+    { selector, str, shouldBlur },
+    async function ({ selector, str, shouldBlur }) {
+      const EventUtils = ContentTaskUtils.getEventUtils(content);
+      let input = content.document.querySelector(selector);
+
+      input.focus();
+      if (!str) {
+        input.select();
+        await EventUtils.synthesizeKey("KEY_Backspace", {}, content);
+      } else if (input.value.startsWith(str)) {
+        info(
+          `New string is substring of value: ${str.length}, ${input.value.length}`
+        );
+        input.setSelectionRange(str.length, input.value.length);
+        await EventUtils.synthesizeKey("KEY_Backspace", {}, content);
+      } else if (str.startsWith(input.value)) {
+        info(
+          `New string appends to value: ${input.value}, ${str.substring(
+            input.value.length
+          )}`
+        );
+        input.setSelectionRange(input.value.length, input.value.length);
+        await EventUtils.sendString(str.substring(input.value.length), content);
+      } else {
+        input.select();
+        await EventUtils.sendString(str, content);
+      }
+
+      if (shouldBlur) {
+        let changedPromise = ContentTaskUtils.waitForEvent(input, "change");
+        input.blur();
+        await changedPromise;
+      }
+
+      Assert.equal(str, input.value, `Expected value '${str}' is set on input`);
+    }
+  );
+  info("Input value changed");
+  await TestUtils.waitForTick();
+}
+
+async function verifyConfirmationHint(
+  browser,
+  forceClose,
+  anchorID = "password-notification-icon"
+) {
+  let hintElem = browser.ownerGlobal.ConfirmationHint._panel;
+  await BrowserTestUtils.waitForPopupEvent(hintElem, "shown");
+  try {
+    Assert.equal(hintElem.state, "open", "hint popup is open");
+    Assert.ok(
+      BrowserTestUtils.isVisible(hintElem.anchorNode),
+      "hint anchorNode is visible"
+    );
+    Assert.equal(
+      hintElem.anchorNode.id,
+      anchorID,
+      "Hint should be anchored on the expected notification icon"
+    );
+    info("verifyConfirmationHint, hint is shown and has its anchorNode");
+    if (forceClose) {
+      await closePopup(hintElem);
+    } else {
+      info("verifyConfirmationHint, assertion ok, wait for poopuphidden");
+      await BrowserTestUtils.waitForPopupEvent(hintElem, "hidden");
+      info("verifyConfirmationHint, hintElem popup is hidden");
+    }
+  } catch (ex) {
+    Assert.ok(false, "Confirmation hint not shown: " + ex.message);
+  } finally {
+    info("verifyConfirmationHint promise finalized");
+  }
+}
diff --git a/toolkit/components/passwordmgr/test/browser/insecure_test.html b/toolkit/components/passwordmgr/test/browser/insecure_test.html
new file mode 100644
index 0000000000..fedea1428e
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/insecure_test.html
@@ -0,0 +1,9 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- This frame is initially loaded over HTTP. -->
+<iframe id="test-iframe"
+        src="http://example.org/browser/toolkit/components/passwordmgr/test/browser/insecure_test_subframe.html"/>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/insecure_test_subframe.html b/toolkit/components/passwordmgr/test/browser/insecure_test_subframe.html
new file mode 100644
index 0000000000..42411ff6bc
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/insecure_test_subframe.html
@@ -0,0 +1,16 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simplest form with username and password fields. -->
+<form id="form-basic" action="https://example.org/custom_action.html">
+  <input id="form-basic-username" name="username">
+  <input id="form-basic-password" name="password" type="password">
+  <input id="form-basic-submit" type="submit">
+</form>
+
+<!-- Link to reload this page over HTTPS. -->
+<a id="test-link"
+   href="https://example.org/browser/toolkit/components/passwordmgr/test/browser/insecure_test_subframe.html">HTTPS</a>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/browser/multiple_forms.html b/toolkit/components/passwordmgr/test/browser/multiple_forms.html
new file mode 100644
index 0000000000..33c5de8a0e
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/multiple_forms.html
@@ -0,0 +1,145 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+
+<form class="test-form"
+      description="Password only form">
+    <input id='test-password-1' type='password' name='pname' value=''>
+    <input type='submit'>Submit</input>
+</form>
+
+<!-- This is a username-only form -->
+<form class="test-form"
+      description="Username only form">
+    <input id='test-username-1' type='text' name='uname' autocomplete='username' value=''>
+    <input type='submit'>Submit</input>
+</form>
+
+<!-- This is NOT a username-only form -->
+<form class="test-form"
+      description="text input only form">
+    <input id='test-input-2' type='text' name='uname' value=''>
+    <input type='submit'>Submit</input>
+</form>
+
+<form class="test-form"
+      description="Simple username and password blank form">
+    <input id='test-username-3' type='text'     name='uname' value=''>
+    <input id='test-password-3' type='password' name='pname' value=''>
+    <button type='submit'>Submit</button>
+</form>
+
+
+<form class="test-form"
+      description="Simple username and password form, prefilled username">
+    <input id='test-username-4' type='text'     name='uname' value='testuser'>
+    <input id='test-password-4' type='password' name='pname' value=''>
+    <button type='submit'>Submit</button>
+</form>
+
+
+<form class="test-form"
+      description="Simple username and password form, prefilled username and password">
+    <input id='test-username-5' type='text'     name='uname' value='testuser'>
+    <input id='test-password-5' type='password' name='pname' value='testpass'>
+    <button type='submit'>Submit</button>
+</form>
+
+
+<form class="test-form"
+      description="One username and two passwords empty form">
+    <input id='test-username-6'  type='text'     name='uname'>
+    <input id='test-password-6'  type='password' name='pname'>
+    <input id='test-password2-6' type='password' name='pname2'>
+    <button type='submit'>Submit</button>
+</form>
+
+
+<form class="test-form"
+      description="One username and two passwords form, fields prefiled">
+    <input id='test-username-7'  type='text'     name='uname' value="testuser">
+    <input id='test-password-7'  type='password' name='pname' value="testpass">
+    <input id='test-password2-7' type='password' name='pname2' value="testpass">
+    <button type='submit'>Submit</button>
+</form>
+
+
+<div class="test-form"
+     description="Username and password fields with no form">
+    <input id='test-username-8' type='text'     name='uname' value="testuser">
+    <input id='test-password-8' type='password' name='pname' value="testpass">
+</div>
+
+
+<form class="test-form"
+      description="Simple username and password blank form, with disabled password">
+    <input id='test-username-9' type='text'     name='uname' value=''>
+    <input id='test-password-9' type='password' name='pname' value='' disabled>
+    <button type='submit'>Submit</button>
+</form>
+
+
+<form class="test-form"
+      description="Simple username and password blank form, with disabled username">
+    <input id='test-username-10' type='text'     name='uname' value='' disabled>
+    <input id='test-password-10' type='password' name='pname' value=''>
+    <button type='submit'>Submit</button>
+</form>
+
+
+<form class="test-form"
+      description="Simple username and password blank form, with readonly password">
+    <input id='test-username-11' type='text'     name='uname' value=''>
+    <input id='test-password-11' type='password' name='pname' value='' readonly>
+    <button type='submit'>Submit</button>
+</form>
+
+
+<form class="test-form"
+      description="Simple username and password blank form, with readonly username">
+    <input id='test-username-12' type='text'     name='uname' value='' readonly>
+    <input id='test-password-12' type='password' name='pname' value=''>
+    <button type='submit'>Submit</button>
+</form>
+
+
+<form class="test-form"
+      description="Two username and one passwords form, fields prefiled">
+    <input id='test-username-13'  type='text'     name='uname'  value="testuser">
+    <input id='test-username2-13' type='text'     name='uname2' value="testuser">
+    <input id='test-password-13'  type='password' name='pname'  value="testpass">
+    <button type='submit'>Submit</button>
+</form>
+
+
+<form class="test-form"
+      description="Two username and one passwords form, one disabled username field">
+    <input id='test-username-14'  type='text'     name='uname'>
+    <input id='test-username2-14' type='text'     name='uname2' disabled>
+    <input id='test-password-14'  type='password' name='pname'>
+    <button type='submit'>Submit</button>
+</form>
+
+
+<div class="test-form"
+     description="Second username and password fields with no form">
+    <input id='test-username-15' type='text'     name='uname'>
+    <input id='test-password-15' type='password' name='pname' expectedFail>
+</div>
+
+<form class="test-form"
+      description="Simple username and password blank form with the password field unmasked by JS">
+    <input id='test-username-16' type='text'     name='uname' value=''>
+    <input id='test-password-16' type='password' name='pname' value='' data-type="password">
+    <button type='submit'>Submit</button>
+</form>
+
+<!-- Form in an iframe -->
+<iframe src="https://example.org/browser/toolkit/components/passwordmgr/test/browser/form_basic.html" id="test-iframe"></iframe>
+
+<script>
+  document.getElementById("test-password-16").type = "text";
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_1.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_1.html
new file mode 100644
index 0000000000..c90fb083ae
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_1.html
@@ -0,0 +1,29 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications - Basic 1un 1pw</title>
+</head>
+<body>
+<h2>Subtest 1</h2>
+<form id="form" action="formsubmit.sjs">
+  <input id="user" name="user">
+  <input id="pass" name="pass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(userField).setUserInput("notifyu1");
+  SpecialPowers.wrap(passField).setUserInput("notifyp1");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_10.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_10.html
new file mode 100644
index 0000000000..7eca613bc3
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_10.html
@@ -0,0 +1,27 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications</title>
+</head>
+<body>
+<h2>Subtest 10</h2>
+<form id="form" action="formsubmit.sjs">
+  <input id="pass" name="pass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(passField).setUserInput("notifyp1");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_11.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_11.html
new file mode 100644
index 0000000000..cd29d0536f
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_11.html
@@ -0,0 +1,26 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications - Popup Windows</title>
+</head>
+<body>
+<h2>Subtest 11 (popup windows)</h2>
+<script>
+
+// Ignore the '?' and split on |
+let [username, password, features, autoClose] = window.location.search.substring(1).split("|");
+
+var url = "subtst_notifications_11_popup.html?" + username + "|" + password;
+var popupWin = window.open(url, "subtst_11", features);
+
+// Popup window will call this function on form submission.
+function formSubmitted() {
+  if (autoClose) {
+    popupWin.close();
+  }
+}
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_11_popup.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_11_popup.html
new file mode 100644
index 0000000000..67aa3fafd8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_11_popup.html
@@ -0,0 +1,32 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications</title>
+</head>
+<body>
+<h2>Subtest 11</h2>
+<form id="form" action="formsubmit.sjs">
+  <input id="user" name="user">
+  <input id="pass" name="pass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  // Get the password from the query string (exclude '?').
+  let [username, password] = window.location.search.substring(1).split("|");
+  SpecialPowers.wrap(userField).setUserInput(username);
+  SpecialPowers.wrap(passField).setUserInput(password);
+  form.submit();
+  window.opener.formSubmitted();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_12_target_blank.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_12_target_blank.html
new file mode 100644
index 0000000000..06c924c2ab
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_12_target_blank.html
@@ -0,0 +1,31 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>target="_blank" subtest for Login Manager notifications</title>
+</head>
+<body>
+<h2>Subtest 12 - target="_blank"</h2>
+<form id="form" action="formsubmit.sjs" target="_blank">
+  <input id="user" name="user">
+  <input id="pass" name="pass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  // Get the password from the query string (exclude '?').
+  let [username, password] = window.location.search.substring(1).split("|");
+  SpecialPowers.wrap(userField).setUserInput(username);
+  SpecialPowers.wrap(passField).setUserInput(password);
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_2.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_2.html
new file mode 100644
index 0000000000..e732252c16
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_2.html
@@ -0,0 +1,30 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications - autocomplete=off on the username field</title>
+</head>
+<body>
+<h2>Subtest 2</h2>
+(username autocomplete=off)
+<form id="form" action="formsubmit.sjs">
+  <input id="user" name="user" autocomplete="off">
+  <input id="pass" name="pass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(userField).setUserInput("notifyu1");
+  SpecialPowers.wrap(passField).setUserInput("notifyp1");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_2pw_0un.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_2pw_0un.html
new file mode 100644
index 0000000000..f6a4b1bf78
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_2pw_0un.html
@@ -0,0 +1,27 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications with 2 password fields and no username</title>
+</head>
+<body>
+<h2>Subtest 24</h2>
+<form id="form" action="formsubmit.sjs">
+  <input id="pass1" name="pass1" type="password" value="staticpw">
+  <input id="pass" name="pass" type="password">
+  <button type="submit">Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(pass).setUserInput("notifyp1");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var pass      = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_2pw_1un_1text.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_2pw_1un_1text.html
new file mode 100644
index 0000000000..d5ccbc8d18
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_2pw_1un_1text.html
@@ -0,0 +1,31 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications with 2 password fields and 1 username field and one other text field before the first password field</title>
+</head>
+<body>
+<h2>1 username field followed by a text field followed by 2 username fields</h2>
+<form id="form" action="formsubmit.sjs">
+  <input id="user"  name="user"  value="staticpw">
+  <input id="city"  name="city"  value="city">
+  <input id="pass"  name="pass"  type="password">
+  <input id="pin"   name="pin"   type="password" value="static-pin">
+  <button type="submit">Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(userField).setUserInput("notifyu1");
+  SpecialPowers.wrap(passField).setUserInput("notifyp1");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_3.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_3.html
new file mode 100644
index 0000000000..1a5e6c3417
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_3.html
@@ -0,0 +1,30 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications - autocomplete=off on the password field</title>
+</head>
+<body>
+<h2>Subtest 3</h2>
+(password autocomplete=off)
+<form id="form" action="formsubmit.sjs">
+  <input id="user" name="user">
+  <input id="pass" name="pass" type="password" autocomplete="off">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(userField).setUserInput("notifyu1");
+  SpecialPowers.wrap(passField).setUserInput("notifyp1");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_4.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_4.html
new file mode 100644
index 0000000000..2df721f995
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_4.html
@@ -0,0 +1,30 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8" >
+  <title>Subtest for Login Manager notifications</title>
+</head>
+<body>
+<h2>Subtest 4</h2>
+(form autocomplete=off)
+<form id="form" action="formsubmit.sjs" autocomplete="off">
+  <input id="user" name="user">
+  <input id="pass" name="pass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(userField).setUserInput("notifyu1");
+  SpecialPowers.wrap(passField).setUserInput("notifyp1");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_5.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_5.html
new file mode 100644
index 0000000000..b0c5034272
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_5.html
@@ -0,0 +1,26 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications - Form with only a username field</title>
+</head>
+<body>
+<h2>Subtest 5</h2>
+<form id="form" action="formsubmit.sjs">
+  <input id="user" name="user">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(userField).setUserInput("notifyu1");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_6.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_6.html
new file mode 100644
index 0000000000..a90930bb59
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_6.html
@@ -0,0 +1,27 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications</title>
+</head>
+<body>
+<h2>Subtest 6</h2>
+(password-only form)
+<form id="form" action="formsubmit.sjs">
+  <input id="pass" name="pass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(passField).setUserInput("notifyp1");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_8.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_8.html
new file mode 100644
index 0000000000..7455d15d90
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_8.html
@@ -0,0 +1,29 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications</title>
+</head>
+<body>
+<h2>Subtest 8</h2>
+<form id="form" action="formsubmit.sjs">
+  <input id="user" name="user">
+  <input id="pass" name="pass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(userField).setUserInput("notifyu1");
+  SpecialPowers.wrap(passField).setUserInput("pass2");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_9.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_9.html
new file mode 100644
index 0000000000..404b4f9a26
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_9.html
@@ -0,0 +1,29 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications</title>
+</head>
+<body>
+<h2>Subtest 9</h2>
+<form id="form" action="formsubmit.sjs">
+  <input id="user" name="user">
+  <input id="pass" name="pass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(userField).setUserInput("");
+  SpecialPowers.wrap(passField).setUserInput("pass2");
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_notifications_change_p.html b/toolkit/components/passwordmgr/test/browser/subtst_notifications_change_p.html
new file mode 100644
index 0000000000..8f52fe9682
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_notifications_change_p.html
@@ -0,0 +1,32 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Subtest for Login Manager notifications</title>
+</head>
+<body>
+<h2>Change password</h2>
+<form id="form" action="formsubmit.sjs">
+  <input id="pass_current" name="pass_current" type="password" value="notifyp1">
+  <input id="pass" name="pass" type="password">
+  <input id="pass_confirm" name="pass_confirm" type="password">
+  <button type='submit'>Submit</button>
+</form>
+
+<script>
+function submitForm() {
+  SpecialPowers.wrap(passField).setUserInput("pass2");
+  SpecialPowers.wrap(passConfirmField).setUserInput("pass2");
+
+  form.submit();
+}
+
+window.onload = submitForm;
+var form      = document.getElementById("form");
+var userField = document.getElementById("user");
+var passField = document.getElementById("pass");
+var passConfirmField = document.getElementById("pass_confirm");
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/browser/subtst_privbrowsing_1.html b/toolkit/components/passwordmgr/test/browser/subtst_privbrowsing_1.html
new file mode 100644
index 0000000000..2ef067ea43
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/browser/subtst_privbrowsing_1.html
@@ -0,0 +1,16 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test Login Manager notifications</title>
+</head>
+<body>
+<h2>Test Login Manager notifications</h2>
+
+<form id="form" action="formsubmit.sjs">
+  <input id="user" name="user" type="text">
+  <input id="pass" name="pass" type="password">
+  <button type='submit'>Submit</button>
+</form>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/formsubmit.sjs b/toolkit/components/passwordmgr/test/formsubmit.sjs
new file mode 100644
index 0000000000..f519234d36
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/formsubmit.sjs
@@ -0,0 +1,37 @@
+function handleRequest(request, response) {
+  try {
+    reallyHandleRequest(request, response);
+  } catch (e) {
+    response.setStatusLine("1.0", 200, "AlmostOK");
+    response.write("Error handling request: " + e);
+  }
+}
+
+function reallyHandleRequest(request, response) {
+  let match;
+
+  // XXX I bet this doesn't work for POST requests.
+  let query = request.queryString;
+
+  let user = null,
+    pass = null;
+  // user=xxx
+  match = /user(?:name)?=([^&]*)/.exec(query);
+  if (match) {
+    user = match[1];
+  }
+
+  // pass=xxx
+  match = /pass(?:word)?=([^&]*)/.exec(query);
+  if (match) {
+    pass = match[1];
+  }
+
+  response.setStatusLine("1.0", 200, "OK");
+
+  response.setHeader("Content-Type", "application/xhtml+xml", false);
+  response.write("<html xmlns='http://www.w3.org/1999/xhtml'>");
+  response.write("<p>User: <span id='user'>" + user + "</span></p>\n");
+  response.write("<p>Pass: <span id='pass'>" + pass + "</span></p>\n");
+  response.write("</html>");
+}
diff --git a/toolkit/components/passwordmgr/test/mochitest/.eslintrc.js b/toolkit/components/passwordmgr/test/mochitest/.eslintrc.js
new file mode 100644
index 0000000000..beb8ec4738
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/.eslintrc.js
@@ -0,0 +1,17 @@
+"use strict";
+
+module.exports = {
+  globals: {
+    promptDone: true,
+    startTest: true,
+    // Make no-undef happy with our runInParent mixed environments since you
+    // can't indicate a single function is a new env.
+    assert: true,
+    addMessageListener: true,
+    sendAsyncMessage: true,
+    Assert: true,
+  },
+  rules: {
+    "no-var": "off",
+  },
+};
diff --git a/toolkit/components/passwordmgr/test/mochitest/auth2/authenticate.sjs b/toolkit/components/passwordmgr/test/mochitest/auth2/authenticate.sjs
new file mode 100644
index 0000000000..bc11bb29f8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/auth2/authenticate.sjs
@@ -0,0 +1,216 @@
+function handleRequest(request, response) {
+  try {
+    reallyHandleRequest(request, response);
+  } catch (e) {
+    response.setStatusLine("1.0", 200, "AlmostOK");
+    response.write("Error handling request: " + e);
+  }
+}
+
+function reallyHandleRequest(request, response) {
+  let match;
+  let requestAuth = true,
+    requestProxyAuth = true;
+
+  // Allow the caller to drive how authentication is processed via the query.
+  // Eg, http://localhost:8888/authenticate.sjs?user=foo&realm=bar
+  // The extra ? allows the user/pass/realm checks to succeed if the name is
+  // at the beginning of the query string.
+  let query = "?" + request.queryString;
+
+  let expected_user = "",
+    expected_pass = "",
+    realm = "mochitest";
+  let proxy_expected_user = "",
+    proxy_expected_pass = "",
+    proxy_realm = "mochi-proxy";
+  let huge = false,
+    plugin = false,
+    anonymous = false;
+  let authHeaderCount = 1;
+  // user=xxx
+  match = /[^_]user=([^&]*)/.exec(query);
+  if (match) {
+    expected_user = match[1];
+  }
+
+  // pass=xxx
+  match = /[^_]pass=([^&]*)/.exec(query);
+  if (match) {
+    expected_pass = match[1];
+  }
+
+  // realm=xxx
+  match = /[^_]realm=([^&]*)/.exec(query);
+  if (match) {
+    realm = match[1];
+  }
+
+  // proxy_user=xxx
+  match = /proxy_user=([^&]*)/.exec(query);
+  if (match) {
+    proxy_expected_user = match[1];
+  }
+
+  // proxy_pass=xxx
+  match = /proxy_pass=([^&]*)/.exec(query);
+  if (match) {
+    proxy_expected_pass = match[1];
+  }
+
+  // proxy_realm=xxx
+  match = /proxy_realm=([^&]*)/.exec(query);
+  if (match) {
+    proxy_realm = match[1];
+  }
+
+  // huge=1
+  match = /huge=1/.exec(query);
+  if (match) {
+    huge = true;
+  }
+
+  // plugin=1
+  match = /plugin=1/.exec(query);
+  if (match) {
+    plugin = true;
+  }
+
+  // multiple=1
+  match = /multiple=([^&]*)/.exec(query);
+  if (match) {
+    authHeaderCount = match[1] + 0;
+  }
+
+  // anonymous=1
+  match = /anonymous=1/.exec(query);
+  if (match) {
+    anonymous = true;
+  }
+
+  // Look for an authentication header, if any, in the request.
+  //
+  // EG: Authorization: Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==
+  //
+  // This test only supports Basic auth. The value sent by the client is
+  // "username:password", obscured with base64 encoding.
+
+  let actual_user = "",
+    actual_pass = "",
+    authHeader,
+    authPresent = false;
+  if (request.hasHeader("Authorization")) {
+    authPresent = true;
+    authHeader = request.getHeader("Authorization");
+    match = /Basic (.+)/.exec(authHeader);
+    if (match.length != 2) {
+      throw new Error("Couldn't parse auth header: " + authHeader);
+    }
+
+    let userpass = atob(match[1]);
+    match = /(.*):(.*)/.exec(userpass);
+    if (match.length != 3) {
+      throw new Error("Couldn't decode auth header: " + userpass);
+    }
+    actual_user = match[1];
+    actual_pass = match[2];
+  }
+
+  let proxy_actual_user = "",
+    proxy_actual_pass = "";
+  if (request.hasHeader("Proxy-Authorization")) {
+    authHeader = request.getHeader("Proxy-Authorization");
+    match = /Basic (.+)/.exec(authHeader);
+    if (match.length != 2) {
+      throw new Error("Couldn't parse auth header: " + authHeader);
+    }
+
+    let userpass = atob(match[1]);
+    match = /(.*):(.*)/.exec(userpass);
+    if (match.length != 3) {
+      throw new Error("Couldn't decode auth header: " + userpass);
+    }
+    proxy_actual_user = match[1];
+    proxy_actual_pass = match[2];
+  }
+
+  // Don't request authentication if the credentials we got were what we
+  // expected.
+  if (expected_user == actual_user && expected_pass == actual_pass) {
+    requestAuth = false;
+  }
+  if (
+    proxy_expected_user == proxy_actual_user &&
+    proxy_expected_pass == proxy_actual_pass
+  ) {
+    requestProxyAuth = false;
+  }
+
+  if (anonymous) {
+    if (authPresent) {
+      response.setStatusLine(
+        "1.0",
+        400,
+        "Unexpected authorization header found"
+      );
+    } else {
+      response.setStatusLine("1.0", 200, "Authorization header not found");
+    }
+  } else if (requestProxyAuth) {
+    response.setStatusLine("1.0", 407, "Proxy authentication required");
+    for (let i = 0; i < authHeaderCount; ++i) {
+      response.setHeader(
+        "Proxy-Authenticate",
+        'basic realm="' + proxy_realm + '"',
+        true
+      );
+    }
+  } else if (requestAuth) {
+    response.setStatusLine("1.0", 401, "Authentication required");
+    for (let i = 0; i < authHeaderCount; ++i) {
+      response.setHeader(
+        "WWW-Authenticate",
+        'basic realm="' + realm + '"',
+        true
+      );
+    }
+  } else {
+    response.setStatusLine("1.0", 200, "OK");
+  }
+
+  response.setHeader("Content-Type", "application/xhtml+xml", false);
+  response.write("<html xmlns='http://www.w3.org/1999/xhtml'>");
+  response.write(
+    "<p>Login: <span id='ok'>" +
+      (requestAuth ? "FAIL" : "PASS") +
+      "</span></p>\n"
+  );
+  response.write(
+    "<p>Proxy: <span id='proxy'>" +
+      (requestProxyAuth ? "FAIL" : "PASS") +
+      "</span></p>\n"
+  );
+  response.write("<p>Auth: <span id='auth'>" + authHeader + "</span></p>\n");
+  response.write("<p>User: <span id='user'>" + actual_user + "</span></p>\n");
+  response.write("<p>Pass: <span id='pass'>" + actual_pass + "</span></p>\n");
+
+  if (huge) {
+    response.write("<div style='display: none'>");
+    for (let i = 0; i < 100000; i++) {
+      response.write("123456789\n");
+    }
+    response.write("</div>");
+    response.write(
+      "<span id='footnote'>This is a footnote after the huge content fill</span>"
+    );
+  }
+
+  if (plugin) {
+    response.write(
+      "<embed id='embedtest' style='width: 400px; height: 100px;' " +
+        "type='application/x-test'></embed>\n"
+    );
+  }
+
+  response.write("</html>");
+}
diff --git a/toolkit/components/passwordmgr/test/mochitest/chrome_timeout.js b/toolkit/components/passwordmgr/test/mochitest/chrome_timeout.js
new file mode 100644
index 0000000000..25a797e1d2
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/chrome_timeout.js
@@ -0,0 +1,14 @@
+/* eslint-env mozilla/chrome-script */
+
+const timer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
+addMessageListener("setTimeout", msg => {
+  timer.init(
+    _ => {
+      sendAsyncMessage("timeout");
+    },
+    msg.delay,
+    Ci.nsITimer.TYPE_ONE_SHOT
+  );
+});
+
+sendAsyncMessage("ready");
diff --git a/toolkit/components/passwordmgr/test/mochitest/file_history_back.html b/toolkit/components/passwordmgr/test/mochitest/file_history_back.html
new file mode 100644
index 0000000000..4e3e071a71
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/file_history_back.html
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="utf-8">
+  </head>
+  <body>
+    This page should navigate back in history upon load.
+  <script>
+    window.onload = function goBack() {
+      window.history.back();
+    };
+  </script>
+  </body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/form_basic_bfcache.html b/toolkit/components/passwordmgr/test/mochitest/form_basic_bfcache.html
new file mode 100644
index 0000000000..852ff950b6
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/form_basic_bfcache.html
@@ -0,0 +1,58 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="utf-8">
+    <script src="/tests/SimpleTest/SimpleTest.js"></script>
+    <script>
+    var bc = new BroadcastChannel("form_basic_bfcache");
+    bc.onmessage = function(event) {
+      if (event.data == "nextpage") {
+        location.href = "https://example.org/tests/toolkit/components/passwordmgr/test/mochitest/file_history_back.html";
+      } else if (event.data == "close") {
+        bc.postMessage("closed");
+        bc.close();
+        window.close();
+        SimpleTest.finish();
+      }
+    }
+
+    function is(val1, val2, msg) {
+      bc.postMessage({type: "is", value1: val1, value2: val2, message: msg});
+    }
+
+    function ok(val, msg) {
+      bc.postMessage({type: "ok", value: val, message: msg});
+    }
+    </script>
+    <script type="text/javascript" src="pwmgr_common.js"></script>
+    <script>
+      // Need to use waitForExplicitFinish also in this support file to
+      // stop SimpleTest complaining about missing checks.
+      // pwmgr_common.js uses internally some helper methods from SimpleTest.
+      SimpleTest.waitForExplicitFinish();
+
+      runChecksAfterCommonInit();
+
+      onpageshow = async function(pageShow) {
+        if (!pageShow.persisted) {
+          // This is the initial page load.
+          await setStoredLoginsAsync([location.origin, "", null, "autofilled", "pass1", "", ""]);
+        } else {
+          await promiseFormsProcessedInSameProcess();
+          let uname = document.getElementById("form-basic-username");
+          let pword = document.getElementById("form-basic-password");
+          checkLoginForm(uname, "autofilled", pword, "pass1");
+        }
+
+        bc.postMessage({type: pageShow.type, persisted: pageShow.persisted});
+      }
+    </script>
+  </head>
+  <body>
+    <form id="form-basic">
+      <input id="form-basic-username" name="username">
+      <input id="form-basic-password" name="password" type="password">
+      <input id="form-basic-submit" type="submit">
+    </form>
+  </body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/form_basic_shadow_DOM_both_fields_together_in_a_shadow_root.html b/toolkit/components/passwordmgr/test/mochitest/form_basic_shadow_DOM_both_fields_together_in_a_shadow_root.html
new file mode 100644
index 0000000000..ab558c4955
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/form_basic_shadow_DOM_both_fields_together_in_a_shadow_root.html
@@ -0,0 +1,31 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simple form with username and password fields together in a shadow root with a <form> ancestor -->
+<!-- This form is based off of toolkit/components/passwordmgr/test/browser/form_basic.html -->
+<form id="both-fields-together-in-a-shadow-root">
+  <!-- username and password inputs generated programmatically below -->
+  <input id="submit" type="submit">
+</form>
+
+<script>
+  const form = document.getElementById("both-fields-together-in-a-shadow-root");
+  const submitButton = document.getElementById("submit");
+  const wrapper = document.createElement("span");
+  wrapper.id = "wrapper-un-and-pw";
+  const shadow = wrapper.attachShadow({mode: "closed"});
+  const fields = ["username", "password"];
+  for (let field of fields) {
+    const inputEle = document.createElement("input");
+    inputEle.id = field;
+    inputEle.name = field;
+    if (field === "password") {
+      inputEle.type = field;
+    }
+    shadow.append(inputEle);
+  }
+  submitButton.before(wrapper);
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/form_basic_shadow_DOM_each_field_in_its_own_shadow_root.html b/toolkit/components/passwordmgr/test/mochitest/form_basic_shadow_DOM_each_field_in_its_own_shadow_root.html
new file mode 100644
index 0000000000..19edd12330
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/form_basic_shadow_DOM_each_field_in_its_own_shadow_root.html
@@ -0,0 +1,31 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simple form with username and password fields each in their own shadow root -->
+<!-- This form is based off of toolkit/components/passwordmgr/test/browser/form_basic.html -->
+<form id="each-field-its-own-shadow">
+  <!-- username and password inputs generated programmatically below -->
+  <input id="submit" type="submit">
+</form>
+
+<script>
+  const form = document.getElementById("each-field-its-own-shadow");
+  const submitButton = document.getElementById("submit");
+  const fields = ["username", "password"];
+  for (let field of fields) {
+    const inputEle = document.createElement("input");
+    inputEle.id = field;
+    inputEle.name = field;
+    if (field === "password") {
+      inputEle.type = field;
+    }
+    const wrapper = document.createElement("span");
+    wrapper.id = `wrapper-${field}`;
+    const shadow = wrapper.attachShadow({mode: "closed"});
+    shadow.append(inputEle);
+    submitButton.before(wrapper);
+  }
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/form_basic_shadow_DOM_form_and_fields_together_in_a_shadow_root.html b/toolkit/components/passwordmgr/test/mochitest/form_basic_shadow_DOM_form_and_fields_together_in_a_shadow_root.html
new file mode 100644
index 0000000000..225fb4e7f8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/form_basic_shadow_DOM_form_and_fields_together_in_a_shadow_root.html
@@ -0,0 +1,33 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simple form with form, username and password fields together in a shadow root -->
+<!-- This form is based off of toolkit/components/passwordmgr/test/browser/form_basic.html -->
+<span id="wrapper">
+  <!-- form and all inputs generated programmatically below -->
+</span>
+
+<script>
+  const wrapper = document.getElementById("wrapper");
+  const shadow = wrapper.attachShadow({mode: "closed"});
+  const form = document.createElement("form");
+  form.id = "form-and-fields-in-a-shadow-root";
+  const submitButton = document.createElement("input");
+  submitButton.id = "submit";
+  submitButton.type = "submit";
+  shadow.append(form);
+  form.append(submitButton);
+  const fields = ["username", "password"];
+  for (let field of fields) {
+    const inputEle = document.createElement("input");
+    inputEle.id = field;
+    inputEle.name = field;
+    if (field === "password") {
+      inputEle.type = field;
+    }
+    submitButton.before(inputEle);
+  }
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/form_nested_shadow_DOM_both_fields_together_in_a_shadow_root.html b/toolkit/components/passwordmgr/test/mochitest/form_nested_shadow_DOM_both_fields_together_in_a_shadow_root.html
new file mode 100644
index 0000000000..876c7d3b85
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/form_nested_shadow_DOM_both_fields_together_in_a_shadow_root.html
@@ -0,0 +1,34 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simple form with username and password fields together in nested shadow roots -->
+<!-- This form is based off of toolkit/components/passwordmgr/test/browser/form_basic.html -->
+<form id="each-field-its-own-shadow">
+  <span id="outer-wrapper">
+    <!-- username and password inputs generated programmatically below -->
+  </span>
+  <input id="submit" type="submit">
+</form>
+
+<script>
+  const submitButton = document.getElementById("submit");
+  const innerWrapper = document.createElement("span");
+  innerWrapper.id = "inner-wrapper";
+  const innerShadow = innerWrapper.attachShadow({mode: "closed"});
+  const outerWrapper = document.getElementById("outer-wrapper");
+  const outerShadow = outerWrapper.attachShadow({mode: "closed"});
+  const fields = ["username", "password"];
+  for (let field of fields) {
+    const inputEle = document.createElement("input");
+    inputEle.id = field;
+    inputEle.name = field;
+    if (field === "password") {
+      inputEle.type = field;
+    }
+    innerShadow.append(inputEle);
+  }
+  outerShadow.append(innerWrapper);
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/form_nested_shadow_DOM_each_field_in_its_own_shadow_root.html b/toolkit/components/passwordmgr/test/mochitest/form_nested_shadow_DOM_each_field_in_its_own_shadow_root.html
new file mode 100644
index 0000000000..9a844f236a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/form_nested_shadow_DOM_each_field_in_its_own_shadow_root.html
@@ -0,0 +1,38 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simple form with username and password fields each in their own nested shadow roots -->
+<!-- This form is based off of toolkit/components/passwordmgr/test/browser/form_basic.html -->
+<form id="each-field-its-own-shadow">
+  <span id="outer-wrapper-username">
+    <!-- username input generated programmatically below -->
+  </span>
+  <span id="outer-wrapper-password">
+    <!-- password input generated programmatically below -->
+  </span>
+  <input id="submit" type="submit">
+</form>
+
+<script>
+  const submitButton = document.getElementById("submit");
+  const fields = ["username", "password"];
+  for (let field of fields) {
+    const inputEle = document.createElement("input");
+    inputEle.id = field;
+    inputEle.name = field;
+    if (field === "password") {
+      inputEle.type = field;
+    }
+    const wrapper = document.createElement("span");
+    wrapper.id = `wrapper-${field}`;
+    const shadow = wrapper.attachShadow({mode: "closed"});
+    shadow.append(inputEle);
+
+    const outerWrapper = document.getElementById(`outer-wrapper-${field}`);
+    const outerShadow = outerWrapper.attachShadow({mode: "closed"});
+    outerShadow.append(wrapper);
+  }
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/form_nested_shadow_DOM_form_and_fields_together_in_a_shadow_root.html b/toolkit/components/passwordmgr/test/mochitest/form_nested_shadow_DOM_form_and_fields_together_in_a_shadow_root.html
new file mode 100644
index 0000000000..79481c4a3a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/form_nested_shadow_DOM_form_and_fields_together_in_a_shadow_root.html
@@ -0,0 +1,37 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simple form with form, username and password fields together in nested shadow roots -->
+<!-- This form is based off of toolkit/components/passwordmgr/test/browser/form_basic.html -->
+<span id="outer-wrapper">
+  <!-- form and all inputs generated programmatically below -->
+</span>
+
+<script>
+  const outerWrapper = document.getElementById("outer-wrapper");
+  const innerWrapper = document.createElement("span");
+  innerWrapper.id = "inner-wrapper";
+  const innerShadow = innerWrapper.attachShadow({mode: "closed"});
+  const outerShadow = outerWrapper.attachShadow({mode: "closed"});
+  const form = document.createElement("form");
+  form.id = "form-and-fields-in-a-shadow-root";
+  const submitButton = document.createElement("input");
+  submitButton.id = "submit";
+  submitButton.type = "submit";
+  innerShadow.append(form);
+  form.append(submitButton);
+  const fields = ["username", "password"];
+  for (let field of fields) {
+    const inputEle = document.createElement("input");
+    inputEle.id = field;
+    inputEle.name = field;
+    if (field === "password") {
+      inputEle.type = field;
+    }
+    submitButton.before(inputEle);
+  }
+  outerShadow.append(innerWrapper);
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/formless_basic_shadow_DOM_both_fields_together_in_a_shadow_root.html b/toolkit/components/passwordmgr/test/mochitest/formless_basic_shadow_DOM_both_fields_together_in_a_shadow_root.html
new file mode 100644
index 0000000000..ed261af9aa
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/formless_basic_shadow_DOM_both_fields_together_in_a_shadow_root.html
@@ -0,0 +1,28 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simple form with username and password fields together in a shadow root -->
+<!-- This form is based off of toolkit/components/passwordmgr/test/browser/formless_basic.html -->
+<!-- username and password inputs generated programmatically below -->
+<input id="submit" type="submit">
+
+<script>
+  const submitButton = document.getElementById("submit");
+  const wrapper = document.createElement("span");
+  wrapper.id = "wrapper-un-and-pw";
+  const shadow = wrapper.attachShadow({mode: "closed"});
+  const fields = ["username", "password"];
+  for (let field of fields) {
+    const inputEle = document.createElement("input");
+    inputEle.id = field;
+    inputEle.name = field;
+    if (field === "password") {
+      inputEle.type = field;
+    }
+    shadow.append(inputEle);
+  }
+  submitButton.before(wrapper);
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/formless_basic_shadow_DOM_each_field_in_its_own_shadow_root.html b/toolkit/components/passwordmgr/test/mochitest/formless_basic_shadow_DOM_each_field_in_its_own_shadow_root.html
new file mode 100644
index 0000000000..b0ea0dc486
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/formless_basic_shadow_DOM_each_field_in_its_own_shadow_root.html
@@ -0,0 +1,28 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simple form with username and password fields each in their own shadow root -->
+<!-- This form is based off of toolkit/components/passwordmgr/test/browser/formless_basic.html -->
+<!-- username and password inputs generated programmatically below -->
+<input id="submit" type="submit">
+
+<script>
+  const submitButton = document.getElementById("submit");
+  const fields = ["username", "password"];
+  for (let field of fields) {
+    const inputEle = document.createElement("input");
+    inputEle.id = field;
+    inputEle.name = field;
+    if (field === "password") {
+      inputEle.type = field;
+    }
+    const wrapper = document.createElement("span");
+    wrapper.id = `wrapper-${field}`;
+    const shadow = wrapper.attachShadow({mode: "closed"});
+    shadow.append(inputEle);
+    submitButton.before(wrapper);
+  }
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/formless_basic_shadow_DOM_form_and_fields_together_in_a_shadow_root.html b/toolkit/components/passwordmgr/test/mochitest/formless_basic_shadow_DOM_form_and_fields_together_in_a_shadow_root.html
new file mode 100644
index 0000000000..a93e5ea752
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/formless_basic_shadow_DOM_form_and_fields_together_in_a_shadow_root.html
@@ -0,0 +1,30 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Simple form with form, username and password fields together in a shadow root -->
+<!-- This form is based off of toolkit/components/passwordmgr/test/browser/formless_basic.html -->
+<span id="wrapper">
+</span>
+<!-- username, password and submit inputs generated programmatically below -->
+
+<script>
+  const wrapper = document.getElementById("wrapper");
+  const shadow = wrapper.attachShadow({mode: "closed"});
+  const fields = ["username", "password"];
+  for (let field of fields) {
+    const inputEle = document.createElement("input");
+    inputEle.id = field;
+    inputEle.name = field;
+    if (field === "password") {
+      inputEle.type = field;
+    }
+    shadow.append(inputEle);
+  }
+  const submitButton = document.createElement("input");
+  submitButton.id = "submit";
+  submitButton.type = "submit";
+  shadow.append(submitButton);
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/mochitest.toml b/toolkit/components/passwordmgr/test/mochitest/mochitest.toml
new file mode 100644
index 0000000000..86d5d83912
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/mochitest.toml
@@ -0,0 +1,419 @@
+[DEFAULT]
+prefs = [
+  "signon.rememberSignons=true",
+  "signon.autofillForms.http=true",
+  "signon.showAutoCompleteFooter=true",
+  'signon.showAutoCompleteImport=""',
+  "signon.testOnlyUserHasInteractedByPrefValue=true",
+  "signon.testOnlyUserHasInteractedWithDocument=true",
+  "network.auth.non-web-content-triggered-resources-http-auth-allow=true",
+  # signon.relatedRealms.enabled pref needed until Bug 1699698 lands
+  "signon.relatedRealms.enabled=true",
+  "signon.usernameOnlyForm.enabled=true",
+  "signon.usernameOnlyForm.lookupThreshold=100",
+  "security.webauth.webauthn_enable_softtoken=true",
+  "security.webauth.webauthn_enable_usbtoken=false",
+  "security.webauthn.enable_conditional_mediation=true",
+]
+support-files = [
+  "../../../prompts/test/chromeScript.js",
+  "!/toolkit/components/prompts/test/prompt_common.js",
+  "../../../satchel/test/parent_utils.js",
+  "!/toolkit/components/satchel/test/satchel_common.js",
+  "../blank.html",
+  "../browser/form_autofocus_js.html",
+  "../browser/form_basic.html",
+  "../browser/formless_basic.html",
+  "../browser/form_cross_origin_secure_action.html",
+  "../browser/form_same_origin_action.html",
+  "auth2/authenticate.sjs",
+  "file_history_back.html",
+  "form_basic_shadow_DOM_both_fields_together_in_a_shadow_root.html",
+  "form_basic_shadow_DOM_each_field_in_its_own_shadow_root.html",
+  "form_basic_shadow_DOM_form_and_fields_together_in_a_shadow_root.html",
+  "form_nested_shadow_DOM_both_fields_together_in_a_shadow_root.html",
+  "form_nested_shadow_DOM_each_field_in_its_own_shadow_root.html",
+  "form_nested_shadow_DOM_form_and_fields_together_in_a_shadow_root.html",
+  "formless_basic_shadow_DOM_both_fields_together_in_a_shadow_root.html",
+  "formless_basic_shadow_DOM_each_field_in_its_own_shadow_root.html",
+  "formless_basic_shadow_DOM_form_and_fields_together_in_a_shadow_root.html",
+  "multiple_forms_shadow_DOM_all_known_variants.html",
+  "pwmgr_common.js",
+  "pwmgr_common_parent.js",
+  "../authenticate.sjs",
+]
+skip-if = ["os == 'android'"] # Don't run on GeckoView
+
+# Note: new tests should use scheme = https unless they have a specific reason not to
+
+["test_DOMInputPasswordAdded_fired_between_DOMContentLoaded_and_load_events.html"]
+scheme = "https"
+support-files = [
+  "slow_image.sjs",
+  "slow_image.html",
+]
+
+["test_LoginManagerContent_passwordEditedOrGenerated.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # password generation
+
+["test_autocomplete_autofill_related_realms_no_dupes.html"]
+skip-if = ["xorigin"]  # Bug 1716412 - New fission platform triage
+scheme = "https"
+
+["test_autocomplete_basic_form.html"]
+skip-if = [
+  "os == 'android'",  # autocomplete
+  "xorigin",  # Bug 1716412 - New fission platform triage
+  "display == 'wayland' && os_version == '22.04'",  # Bug 1857071
+]
+scheme = "https"
+
+["test_autocomplete_basic_form_formActionOrigin.html"]
+skip-if = [
+  "os == 'android'", # android:autocomplete.
+  "xorigin",  # Bug 1716412 - New fission platform triage
+]
+scheme = "https"
+
+["test_autocomplete_basic_form_insecure.html"]
+skip-if = [
+  "os == 'android'",  # autocomplete
+  "xorigin",  # Bug 1716412 - New fission platform triage
+]
+
+["test_autocomplete_basic_form_related_realms.html"]
+skip-if = ["xorigin"]  # Bug 1716412 - New fission platform triage
+scheme = "https"
+
+["test_autocomplete_hasBeenTypePassword.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # autocomplete
+
+["test_autocomplete_highlight.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # autocomplete
+
+["test_autocomplete_highlight_non_login.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # autocomplete
+
+["test_autocomplete_highlight_username_only_form.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # autocomplete
+
+["test_autocomplete_https_downgrade.html"]
+scheme = "http" # Tests downgrading
+skip-if = [
+  "os == 'android'",  # autocomplete
+  "os == 'linux' && debug",  # Bug 1554959
+  "xorigin",  # Bug 1716412 - New fission platform triage
+]
+
+["test_autocomplete_https_upgrade.html"]
+scheme = "https"
+skip-if = [
+  "verify",
+  "os == 'android'", # autocomplete
+  "os == 'linux' && debug", # Bug 1554959 for linux debug disable
+]
+
+["test_autocomplete_password_generation.html"]
+scheme = "https"
+skip-if = [
+  "xorigin",
+  "os == 'android'", # autocomplete
+]
+
+["test_autocomplete_password_generation_confirm.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # autocomplete
+
+["test_autocomplete_password_generation_telemetry.html"]
+scheme = "https"
+skip-if = [
+  "xorigin",
+  "os == 'android'", # autocomplete
+]
+
+["test_autocomplete_password_open.html"]
+scheme = "https"
+skip-if = [
+  "os == 'android'", # autocomplete
+  "verify",
+]
+
+["test_autocomplete_sandboxed.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # autocomplete
+
+["test_autocomplete_tab_between_fields.html"]
+scheme = "https"
+skip-if = [
+  "xorigin",
+  "os == 'android'", # autocomplete
+]
+
+["test_autofill_autocomplete_types.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # bug 1533965
+
+["test_autofill_different_formActionOrigin.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # Bug 1259768
+
+["test_autofill_different_subdomain.html"]
+scheme = "https"
+skip-if = [
+  "os == 'android'", # Bug 1259768
+  "http3",
+  "http2",
+]
+
+["test_autofill_from_bfcache.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # bug 1527403
+support-files = ["form_basic_bfcache.html"]
+
+["test_autofill_hasBeenTypePassword.html"]
+scheme = "https"
+
+["test_autofill_highlight.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # Bug 1531185
+
+["test_autofill_highlight_empty_username.html"]
+scheme = "https"
+
+["test_autofill_highlight_username_only_form.html"]
+scheme = "https"
+
+["test_autofill_https_downgrade.html"]
+scheme = "http"  # we need http to test handling of https logins on http forms
+skip-if = [
+  "http3",
+  "http2",
+]
+
+["test_autofill_https_upgrade.html"]
+skip-if = [
+  "os == 'android'", # Bug 1259768
+  "http3",
+  "http2",
+]
+
+["test_autofill_password-only.html"]
+
+["test_autofill_sandboxed.html"]
+scheme = "https"
+skip-if = ["os == 'android'"]
+
+["test_autofill_tab_between_fields.html"]
+scheme = "https"
+
+["test_autofill_username-only.html"]
+
+["test_autofill_username-only_threshold.html"]
+
+["test_autofocus_js.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # autocomplete
+
+["test_basic_form.html"]
+
+["test_basic_form_0pw.html"]
+
+["test_basic_form_1pw.html"]
+
+["test_basic_form_1pw_2.html"]
+
+["test_basic_form_2pw_1.html"]
+
+["test_basic_form_2pw_2.html"]
+
+["test_basic_form_3pw_1.html"]
+
+["test_basic_form_honor_autocomplete_off.html"]
+scheme = "https"
+skip-if = [
+  "xorigin",
+  "os == 'android'", # android:autocomplete.
+]
+
+["test_basic_form_html5.html"]
+
+["test_basic_form_pwevent.html"]
+skip-if = ["xorigin"]
+
+["test_basic_form_pwonly.html"]
+
+["test_bug_627616.html"]
+skip-if = [
+  "os == 'android'", # Tests desktop prompts
+  "http3",
+  "http2",
+]
+
+["test_bug_776171.html"]
+
+["test_case_differences.html"]
+skip-if = ["os == 'android'"] # autocomplete
+scheme = "https"
+
+["test_dismissed_doorhanger_in_shadow_DOM.html"]
+skip-if = ["os == 'android'"] # Tests desktop prompt
+scheme = "https"
+
+["test_formLike_rootElement_with_Shadow_DOM.html"]
+scheme = "https"
+
+["test_form_action_1.html"]
+
+["test_form_action_2.html"]
+
+["test_form_action_javascript.html"]
+
+["test_formless_autofill.html"]
+skip-if = [
+  "xorigin",
+  "http3",
+  "http2",
+]
+
+["test_formless_submit.html"]
+skip-if = [
+  "os == 'android' && debug", # bug 1397615
+  "http3",
+  "http2",
+]
+
+["test_formless_submit_form_removal.html"]
+skip-if = [
+  "http3",
+  "http2",
+]
+
+["test_formless_submit_form_removal_negative.html"]
+skip-if = [
+  "http3",
+  "http2",
+]
+
+["test_formless_submit_navigation.html"]
+skip-if = [
+  "os == 'android' && debug", # bug 1397615
+  "http3",
+  "http2",
+]
+
+["test_formless_submit_navigation_negative.html"]
+skip-if = [
+  "os == 'android' && debug", # bug 1397615
+  "http3",
+  "http2",
+]
+
+["test_include_other_subdomains_in_lookup.html"]
+skip-if = ["os == 'android'"] # android:autocomplete.
+scheme = "https"
+
+["test_input_events.html"]
+skip-if = ["xorigin"]
+
+["test_input_events_for_identical_values.html"]
+
+["test_insecure_form_field_no_saved_login.html"]
+skip-if = ["os == 'android'"] # android:autocomplete.
+
+["test_maxlength.html"]
+
+["test_munged_values.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # bug 1527403
+
+["test_one_doorhanger_per_un_pw.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # bug 1535505
+
+["test_onsubmit_value_change.html"]
+
+["test_password_field_autocomplete.html"]
+skip-if = ["os == 'android'"] # android:autocomplete.
+
+["test_password_length.html"]
+scheme = "https"
+skip-if = ["os == 'android'"] # bug 1527403
+
+["test_passwords_in_type_password.html"]
+
+["test_primary_password.html"]
+scheme = "https"
+run-if = ["os == 'mac'"]
+skip-if = [
+  "verify",
+  "xorigin", # Tests desktop prompts and bug 1333264
+]
+support-files = [
+  "chrome_timeout.js",
+  "subtst_primary_pass.html",
+]
+
+["test_prompt.html"]
+skip-if = [
+  "os == 'linux'",
+  "os == 'android'", # Tests desktop prompts
+]
+
+["test_prompt_async.html"]
+skip-if = [
+  "os == 'android'", # Tests desktop prompts
+  "http3",
+  "http2",
+]
+support-files = ["subtst_prompt_async.html"]
+
+["test_prompt_http.html"]
+skip-if = [
+  "os == 'android'",  # Tests desktop prompts
+  "os == 'linux'",
+  "xorigin",  # Bug 1716412 - New fission platform triage
+]
+
+["test_prompt_noWindow.html"]
+skip-if = ["os == 'android'"] # Tests desktop prompts.
+
+["test_prompt_promptAuth.html"]
+skip-if = [
+  "os == 'linux'",
+  "os == 'android'", # Tests desktop prompts
+]
+
+["test_prompt_promptAuth_proxy.html"]
+skip-if = [
+  "os == 'linux'",
+  "os == 'android'", # Tests desktop prompts
+]
+
+["test_recipe_login_fields.html"]
+skip-if = ["xorigin"]
+
+["test_set_stored_logins_during_task.html"]
+
+["test_submit_without_field_modifications.html"]
+support-files = ["subtst_prefilled_form.html"]
+skip-if = [
+  "xorigin",
+  "http3",
+  "http2",
+]
+
+["test_username_focus.html"]
+skip-if = [
+  "xorigin",
+  "os == 'android'", # android:autocomplete.
+]
+
+["test_xhr.html"]
+skip-if = ["os == 'android'"] # Tests desktop prompts
+
+["test_xhr_2.html"]
diff --git a/toolkit/components/passwordmgr/test/mochitest/multiple_forms_shadow_DOM_all_known_variants.html b/toolkit/components/passwordmgr/test/mochitest/multiple_forms_shadow_DOM_all_known_variants.html
new file mode 100644
index 0000000000..5ba547e671
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/multiple_forms_shadow_DOM_all_known_variants.html
@@ -0,0 +1,111 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Page with multiple forms containing the following Shadow DOM variants: -->
+<!-- Case 1: Each field (username and password) in its own shadow root -->
+<!-- Case 2: Both fields (username and password) together in a shadow root with a form ancestor -->
+<!-- Case 3: Form and fields (username and password) together in a shadow root -->
+<span id="outer-wrapper">
+</span>
+
+<script>
+  const outerWrapper = document.getElementById("outer-wrapper");
+  const outerShadow = outerWrapper.attachShadow({mode: "closed"});
+
+  function makeFormlessOuterForm(scenario) {
+    const fields = ["username", "password"];
+    for (let field of fields) {
+      const inputEle = document.createElement("input");
+      inputEle.id = `${field}-${scenario}`;
+      inputEle.name = `${field}-${scenario}`;
+      if (field === "password") {
+        inputEle.type = field;
+      }
+      outerShadow.append(inputEle);
+    }
+    const submitButton = document.createElement("input");
+    submitButton.id = `submit-${scenario}`;
+    submitButton.type = "submit";
+    outerShadow.append(submitButton);
+  }
+
+  function makeFormEachFieldInItsOwnShadowRoot(scenario) {
+    const form = document.createElement("form");
+    form.id = scenario;
+    const submitButton = document.createElement("input");
+    submitButton.id = `submit-${scenario}`;
+    submitButton.type = "submit";
+    form.append(submitButton);
+    const fields = ["username", "password"];
+    for (let field of fields) {
+      const inputEle = document.createElement("input");
+      inputEle.id = `${field}-${scenario}`;
+      inputEle.name = `${field}-${scenario}`;
+      if (field === "password") {
+        inputEle.type = field;
+      }
+      const wrapper = document.createElement("span");
+      wrapper.id = `wrapper-${field}-${scenario}`;
+      const shadow = wrapper.attachShadow({mode: "closed"});
+      shadow.append(inputEle);
+      submitButton.before(wrapper);
+    }
+    outerShadow.append(form);
+  }
+
+  function makeFormBothFieldsTogetherInAShadowRoot(scenario) {
+    const form = document.createElement("form");
+    form.id = scenario;
+    const submitButton = document.createElement("input");
+    submitButton.id = `submit-${scenario}`;
+    submitButton.type = "submit";
+    form.append(submitButton);
+    const wrapper = document.createElement("span");
+    wrapper.id = `wrapper-${scenario}`;
+    const shadow = wrapper.attachShadow({mode: "closed"});
+    const fields = ["username", "password"];
+    for (let field of fields) {
+      const inputEle = document.createElement("input");
+      inputEle.id = `${field}-${scenario}`;
+      inputEle.name = `${field}-${scenario}`;
+      if (field === "password") {
+        inputEle.type = field;
+      }
+      shadow.append(inputEle);
+    }
+    submitButton.before(wrapper);
+    outerShadow.append(form);
+  }
+
+  function makeFormFormAndFieldsTogetherInAShadowRoot(scenario) {
+    const wrapper = document.createElement("span");
+    wrapper.id = `wrapper-${scenario}`;
+    const shadow = wrapper.attachShadow({mode: "closed"});
+    const form = document.createElement("form");
+    form.id = scenario;
+    shadow.append(form);
+    const submitButton = document.createElement("input");
+    submitButton.id = `submit-${scenario}`;
+    submitButton.type = "submit";
+    form.append(submitButton);
+    const fields = ["username", "password"];
+    for (let field of fields) {
+      const inputEle = document.createElement("input");
+      inputEle.id = field;
+      inputEle.name = field;
+      if (field === "password") {
+        inputEle.type = field;
+      }
+      submitButton.before(inputEle);
+    }
+    outerShadow.append(wrapper);
+  }
+
+  makeFormlessOuterForm("formless-case-2");
+  makeFormEachFieldInItsOwnShadowRoot("form-case-1");
+  makeFormBothFieldsTogetherInAShadowRoot("form-case-2");
+  makeFormFormAndFieldsTogetherInAShadowRoot("form-case-3");
+</script>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/pwmgr_common.js b/toolkit/components/passwordmgr/test/mochitest/pwmgr_common.js
new file mode 100644
index 0000000000..8b125897a5
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/pwmgr_common.js
@@ -0,0 +1,1175 @@
+/**
+ * Helpers for password manager mochitest-plain tests.
+ */
+
+/* import-globals-from ../../../../../toolkit/components/satchel/test/satchel_common.js */
+
+const { LoginTestUtils } = SpecialPowers.ChromeUtils.importESModule(
+  "resource://testing-common/LoginTestUtils.sys.mjs"
+);
+const Services = SpecialPowers.Services;
+
+// Setup LoginTestUtils to report assertions to the mochitest harness.
+LoginTestUtils.setAssertReporter(
+  SpecialPowers.wrapCallback((err, message, stack) => {
+    SimpleTest.record(!err, err ? err.message : message, null, stack);
+  })
+);
+
+const { LoginHelper } = SpecialPowers.ChromeUtils.importESModule(
+  "resource://gre/modules/LoginHelper.sys.mjs"
+);
+
+const { LENGTH: GENERATED_PASSWORD_LENGTH, REGEX: GENERATED_PASSWORD_REGEX } =
+  LoginTestUtils.generation;
+const LOGIN_FIELD_UTILS = LoginTestUtils.loginField;
+const TESTS_DIR = "/tests/toolkit/components/passwordmgr/test/";
+
+// Depending on pref state we either show auth prompts as windows or on tab level.
+let authPromptModalType = SpecialPowers.Services.prefs.getIntPref(
+  "prompts.modalType.httpAuth"
+);
+
+// Whether the auth prompt is a commonDialog.xhtml or a TabModalPrompt
+let authPromptIsCommonDialog =
+  authPromptModalType === SpecialPowers.Services.prompt.MODAL_TYPE_WINDOW ||
+  (authPromptModalType === SpecialPowers.Services.prompt.MODAL_TYPE_TAB &&
+    SpecialPowers.Services.prefs.getBoolPref(
+      "prompts.tabChromePromptSubDialog",
+      false
+    ));
+
+/**
+ * Recreate a DOM tree using the outerHTML to ensure that any event listeners
+ * and internal state for the elements are removed.
+ */
+function recreateTree(element) {
+  // eslint-disable-next-line no-self-assign
+  element.outerHTML = element.outerHTML;
+}
+
+function _checkArrayValues(actualValues, expectedValues, msg) {
+  is(
+    actualValues.length,
+    expectedValues.length,
+    "Checking array values: " + msg
+  );
+  for (let i = 0; i < expectedValues.length; i++) {
+    is(actualValues[i], expectedValues[i], msg + " Checking array entry #" + i);
+  }
+}
+
+/**
+ * Check autocomplete popup results to ensure that expected
+ * *labels* are being shown correctly as items in the popup.
+ */
+function checkAutoCompleteResults(actualValues, expectedValues, hostname, msg) {
+  if (hostname === null) {
+    _checkArrayValues(actualValues, expectedValues, msg);
+    return;
+  }
+
+  isnot(
+    actualValues.length,
+    0,
+    "There should be items in the autocomplete popup: " +
+      JSON.stringify(actualValues)
+  );
+
+  // Check the footer first.
+  let footerResult = actualValues[actualValues.length - 1];
+  is(footerResult, "Manage Passwords", "the footer text is shown correctly");
+
+  if (actualValues.length == 1) {
+    is(
+      expectedValues.length,
+      0,
+      "If only the footer is present then there should be no expectedValues"
+    );
+    info("Only the footer is present in the popup");
+    return;
+  }
+
+  // Check the rest of the autocomplete item values.
+  _checkArrayValues(actualValues.slice(0, -1), expectedValues, msg);
+}
+
+/**
+ * Wait for autocomplete popup to get closed
+ * @return {Promise} resolving when the AC popup is closed
+ */
+async function untilAutocompletePopupClosed() {
+  return SimpleTest.promiseWaitForCondition(async () => {
+    const popupState = await getPopupState();
+    return !popupState.open;
+  }, "Wait for autocomplete popup to be closed");
+}
+
+function getIframeBrowsingContext(window, iframeNumber = 0) {
+  let bc = SpecialPowers.wrap(window).windowGlobalChild.browsingContext;
+  return SpecialPowers.unwrap(bc.children[iframeNumber]);
+}
+
+/**
+ * Set input values via setUserInput to emulate user input
+ * and distinguish them from declarative or script-assigned values
+ */
+function setUserInputValues(parentNode, selectorValues, userInput = true) {
+  for (let [selector, newValue] of Object.entries(selectorValues)) {
+    info(`setUserInputValues, selector: ${selector}`);
+    try {
+      let field = SpecialPowers.wrap(parentNode.querySelector(selector));
+      if (field.value == newValue) {
+        // we don't get an input event if the new value == the old
+        field.value += "#";
+      }
+      if (userInput) {
+        field.setUserInput(newValue);
+      } else {
+        field.value = newValue;
+      }
+    } catch (ex) {
+      info(ex.message);
+      info(ex.stack);
+      ok(
+        false,
+        `setUserInputValues: Couldn't set value of field: ${ex.message}`
+      );
+    }
+  }
+}
+
+/**
+ * @param {Function} [aFilterFn = undefined] Function to filter out irrelevant submissions.
+ * @return {Promise} resolving when a relevant form submission was processed.
+ */
+function getSubmitMessage(aFilterFn = undefined) {
+  info("getSubmitMessage");
+  return new Promise((resolve, reject) => {
+    PWMGR_COMMON_PARENT.addMessageListener(
+      "formSubmissionProcessed",
+      function processed(...args) {
+        if (aFilterFn && !aFilterFn(...args)) {
+          // This submission isn't the one we're waiting for.
+          return;
+        }
+
+        info("got formSubmissionProcessed");
+        PWMGR_COMMON_PARENT.removeMessageListener(
+          "formSubmissionProcessed",
+          processed
+        );
+        resolve(args[0]);
+      }
+    );
+  });
+}
+
+/**
+ * @return {Promise} resolves when a onPasswordEditedOrGenerated message is received at the parent
+ */
+function getPasswordEditedMessage() {
+  info("getPasswordEditedMessage");
+  return new Promise((resolve, reject) => {
+    PWMGR_COMMON_PARENT.addMessageListener(
+      "passwordEditedOrGenerated",
+      function listener(...args) {
+        info("got passwordEditedOrGenerated");
+        PWMGR_COMMON_PARENT.removeMessageListener(
+          "passwordEditedOrGenerated",
+          listener
+        );
+        resolve(args[0]);
+      }
+    );
+  });
+}
+
+/**
+ * Create a login form and insert into contents dom (identified by id
+ * `content`). If the form (identified by its number) is already present in the
+ * dom, it gets replaced.
+ *
+ * @param {number} [num = 1] - number of the form, used as id, eg `form1`
+ * @param {string} [action = ""] - action attribute of the form
+ * @param {string} [autocomplete  = null] - forms autocomplete attribute. Default is none
+ * @param {object} [username = {}] - object describing attributes to the username field:
+ * @param {string} [username.id = null] - id of the field
+ * @param {string} [username.name = "uname"] - name attribute
+ * @param {string} [username.type = "text"] - type of the field
+ * @param {string} [username.value = null] - initial value of the field
+ * @param {string} [username.autocomplete = null] - autocomplete attribute
+ * @param {object} [password = {}] - an object describing attributes to the password field. If falsy, do not create a password field
+ * @param {string} [password.id = null] - id of the field
+ * @param {string} [password.name = "pword"] - name attribute
+ * @param {string} [password.type = "password"] - type of the field
+ * @param {string} [password.value = null] - initial value of the field
+ * @param {string} [password.label = null] - if present, wrap field in a label containing its value
+ * @param {string} [password.autocomplete = null] - autocomplete attribute
+ *
+ * @return {HTMLDomElement} the form
+ */
+function createLoginForm({
+  num = 1,
+  action = "",
+  autocomplete = null,
+  username = {},
+  password = {},
+} = {}) {
+  username.name ||= "uname";
+  username.type ||= "text";
+  username.id ||= null;
+  username.value ||= null;
+  username.autocomplete ||= null;
+
+  password.name ||= "pword";
+  password.type ||= "password";
+  password.id ||= null;
+  password.value ||= null;
+  password.label ||= null;
+  password.autocomplete ||= null;
+  password.readonly ||= null;
+  password.disabled ||= null;
+
+  info(
+    `Creating login form ${JSON.stringify({ num, action, username, password })}`
+  );
+
+  const form = document.createElement("form");
+  form.id = `form${num}`;
+  form.action = action;
+  form.onsubmit = () => false;
+
+  if (autocomplete != null) {
+    form.setAttribute("autocomplete", autocomplete);
+  }
+
+  const usernameInput = document.createElement("input");
+
+  usernameInput.type = username.type;
+  usernameInput.name = username.name;
+
+  if (username.id != null) {
+    usernameInput.id = username.id;
+  }
+  if (username.value != null) {
+    usernameInput.value = username.value;
+  }
+  if (username.autocomplete != null) {
+    usernameInput.setAttribute("autocomplete", username.autocomplete);
+  }
+
+  form.appendChild(usernameInput);
+
+  if (password) {
+    const passwordInput = document.createElement("input");
+
+    passwordInput.type = password.type;
+    passwordInput.name = password.name;
+
+    if (password.id != null) {
+      passwordInput.id = password.id;
+    }
+    if (password.value != null) {
+      passwordInput.value = password.value;
+    }
+    if (password.autocomplete != null) {
+      passwordInput.setAttribute("autocomplete", password.autocomplete);
+    }
+    if (password.readonly != null) {
+      passwordInput.setAttribute("readonly", password.readonly);
+    }
+    if (password.disabled != null) {
+      passwordInput.setAttribute("disabled", password.disabled);
+    }
+
+    if (password.label != null) {
+      const passwordLabel = document.createElement("label");
+      passwordLabel.innerText = password.label;
+      passwordLabel.appendChild(passwordInput);
+      form.appendChild(passwordLabel);
+    } else {
+      form.appendChild(passwordInput);
+    }
+  }
+
+  const submitButton = document.createElement("button");
+  submitButton.type = "submit";
+  submitButton.name = "submit";
+  submitButton.innerText = "Submit";
+  form.appendChild(submitButton);
+
+  const content = document.getElementById("content");
+
+  const oldForm = document.getElementById(form.id);
+  if (oldForm) {
+    content.replaceChild(form, oldForm);
+  } else {
+    content.appendChild(form);
+  }
+
+  return form;
+}
+
+/**
+ * Check for expected username/password in form.
+ * @see `checkForm` below for a similar function.
+ */
+function checkLoginForm(
+  usernameField,
+  expectedUsername,
+  passwordField,
+  expectedPassword
+) {
+  let formID = usernameField.parentNode.id;
+  is(
+    usernameField.value,
+    expectedUsername,
+    "Checking " + formID + " username is: " + expectedUsername
+  );
+  is(
+    passwordField.value,
+    expectedPassword,
+    "Checking " + formID + " password is: " + expectedPassword
+  );
+}
+
+/**
+ * Check repeatedly for a while to see if a particular condition still applies.
+ * This function checks the return value of `condition` repeatedly until either
+ * the condition has a falsy return value, or `retryTimes` is exceeded.
+ */
+
+function ensureCondition(
+  condition,
+  errorMsg = "Condition did not last.",
+  retryTimes = 10
+) {
+  return new Promise((resolve, reject) => {
+    let tries = 0;
+    let conditionFailed = false;
+    let interval = setInterval(async function () {
+      try {
+        const conditionPassed = await condition();
+        conditionFailed ||= !conditionPassed;
+      } catch (e) {
+        ok(false, e + "\n" + e.stack);
+        conditionFailed = true;
+      }
+      if (conditionFailed || tries >= retryTimes) {
+        ok(!conditionFailed, errorMsg);
+        clearInterval(interval);
+        if (conditionFailed) {
+          reject(errorMsg);
+        } else {
+          resolve();
+        }
+      }
+      tries++;
+    }, 100);
+  });
+}
+
+/**
+ * Wait a while to ensure login form stays filled with username and password
+ * @see `checkLoginForm` below for a similar function.
+ * @returns a promise, resolving when done
+ *
+ * TODO: eventually get rid of this time based check, and transition to an
+ * event based approach. See Bug 1811142.
+ * Filling happens by `_fillForm()` which can report it's decision and we can
+ * wait for it. One of the options is to have `didFillFormAsync()` from
+ * https://phabricator.services.mozilla.com/D167214#change-3njWgUgqswws
+ */
+function ensureLoginFormStaysFilledWith(
+  usernameField,
+  expectedUsername,
+  passwordField,
+  expectedPassword
+) {
+  return ensureCondition(() => {
+    return (
+      Object.is(usernameField.value, expectedUsername) &&
+      Object.is(passwordField.value, expectedPassword)
+    );
+  }, `Ensuring form ${usernameField.parentNode.id} stays filled with "${expectedUsername}:${expectedPassword}"`);
+}
+
+function checkLoginFormInFrame(
+  iframeBC,
+  usernameFieldId,
+  expectedUsername,
+  passwordFieldId,
+  expectedPassword
+) {
+  return SpecialPowers.spawn(
+    iframeBC,
+    [usernameFieldId, expectedUsername, passwordFieldId, expectedPassword],
+    (
+      usernameFieldIdF,
+      expectedUsernameF,
+      passwordFieldIdF,
+      expectedPasswordF
+    ) => {
+      let usernameField =
+        this.content.document.getElementById(usernameFieldIdF);
+      let passwordField =
+        this.content.document.getElementById(passwordFieldIdF);
+
+      let formID = usernameField.parentNode.id;
+      Assert.equal(
+        usernameField.value,
+        expectedUsernameF,
+        "Checking " + formID + " username is: " + expectedUsernameF
+      );
+      Assert.equal(
+        passwordField.value,
+        expectedPasswordF,
+        "Checking " + formID + " password is: " + expectedPasswordF
+      );
+    }
+  );
+}
+
+async function checkUnmodifiedFormInFrame(bc, formNum) {
+  return SpecialPowers.spawn(bc, [formNum], formNumF => {
+    let form = this.content.document.getElementById(`form${formNumF}`);
+    ok(form, "Locating form " + formNumF);
+
+    for (var i = 0; i < form.elements.length; i++) {
+      var ele = form.elements[i];
+
+      // No point in checking form submit/reset buttons.
+      if (ele.type == "submit" || ele.type == "reset") {
+        continue;
+      }
+
+      is(
+        ele.value,
+        ele.defaultValue,
+        "Test to default value of field " + ele.name + " in form " + formNumF
+      );
+    }
+  });
+}
+
+/**
+ * Check a form for expected values even if it is in a different top level window
+ * or process. If an argument is null, a field's expected value will be the default
+ * value.
+ *
+ * Similar to the checkForm helper, but it works across (cross-origin) frames.
+ *
+ * <form id="form#">
+ * checkLoginFormInFrameWithElementValues(#, "foo");
+ */
+async function checkLoginFormInFrameWithElementValues(
+  browsingContext,
+  formNum,
+  ...values
+) {
+  return SpecialPowers.spawn(
+    browsingContext,
+    [formNum, values],
+    function checkFormWithElementValues(formNumF, valuesF) {
+      let [val1F, val2F, val3F] = valuesF;
+      let doc = this.content.document;
+      let e;
+      let form = doc.getElementById("form" + formNumF);
+      ok(form, "Locating form " + formNumF);
+
+      let numToCheck = arguments.length - 1;
+
+      if (!numToCheck--) {
+        return;
+      }
+      e = form.elements[0];
+      if (val1F == null) {
+        is(
+          e.value,
+          e.defaultValue,
+          "Test default value of field " + e.name + " in form " + formNumF
+        );
+      } else {
+        is(
+          e.value,
+          val1F,
+          "Test value of field " + e.name + " in form " + formNumF
+        );
+      }
+
+      if (!numToCheck--) {
+        return;
+      }
+
+      e = form.elements[1];
+      if (val2F == null) {
+        is(
+          e.value,
+          e.defaultValue,
+          "Test default value of field " + e.name + " in form " + formNumF
+        );
+      } else {
+        is(
+          e.value,
+          val2F,
+          "Test value of field " + e.name + " in form " + formNumF
+        );
+      }
+
+      if (!numToCheck--) {
+        return;
+      }
+      e = form.elements[2];
+      if (val3F == null) {
+        is(
+          e.value,
+          e.defaultValue,
+          "Test default value of field " + e.name + " in form " + formNumF
+        );
+      } else {
+        is(
+          e.value,
+          val3F,
+          "Test value of field " + e.name + " in form " + formNumF
+        );
+      }
+    }
+  );
+}
+
+/**
+ * Check a form for expected values. If an argument is null, a field's
+ * expected value will be the default value.
+ *
+ * <form id="form#">
+ * checkForm(#, "foo");
+ */
+function checkForm(formNum, val1, val2, val3) {
+  var e,
+    form = document.getElementById("form" + formNum);
+  ok(form, "Locating form " + formNum);
+
+  var numToCheck = arguments.length - 1;
+
+  if (!numToCheck--) {
+    return;
+  }
+  e = form.elements[0];
+  if (val1 == null) {
+    is(
+      e.value,
+      e.defaultValue,
+      "Test default value of field " + e.name + " in form " + formNum
+    );
+  } else {
+    is(e.value, val1, "Test value of field " + e.name + " in form " + formNum);
+  }
+
+  if (!numToCheck--) {
+    return;
+  }
+  e = form.elements[1];
+  if (val2 == null) {
+    is(
+      e.value,
+      e.defaultValue,
+      "Test default value of field " + e.name + " in form " + formNum
+    );
+  } else {
+    is(e.value, val2, "Test value of field " + e.name + " in form " + formNum);
+  }
+
+  if (!numToCheck--) {
+    return;
+  }
+  e = form.elements[2];
+  if (val3 == null) {
+    is(
+      e.value,
+      e.defaultValue,
+      "Test default value of field " + e.name + " in form " + formNum
+    );
+  } else {
+    is(e.value, val3, "Test value of field " + e.name + " in form " + formNum);
+  }
+}
+
+/**
+ * Check a form for unmodified values from when page was loaded.
+ *
+ * <form id="form#">
+ * checkUnmodifiedForm(#);
+ */
+function checkUnmodifiedForm(formNum) {
+  var form = document.getElementById("form" + formNum);
+  ok(form, "Locating form " + formNum);
+
+  for (var i = 0; i < form.elements.length; i++) {
+    var ele = form.elements[i];
+
+    // No point in checking form submit/reset buttons.
+    if (ele.type == "submit" || ele.type == "reset") {
+      continue;
+    }
+
+    is(
+      ele.value,
+      ele.defaultValue,
+      "Test to default value of field " + ele.name + " in form " + formNum
+    );
+  }
+}
+
+/**
+ * Wait for the document to be ready and any existing password fields on
+ * forms to be processed.
+ *
+ * @param existingPasswordFieldsCount the number of password fields
+ * that begin on the test page.
+ */
+function registerRunTests(existingPasswordFieldsCount = 0, callback) {
+  return new Promise(resolve => {
+    function onDOMContentLoaded() {
+      var form = document.createElement("form");
+      form.id = "observerforcer";
+      var username = document.createElement("input");
+      username.name = "testuser";
+      form.appendChild(username);
+      var password = document.createElement("input");
+      password.name = "testpass";
+      password.type = "password";
+      form.appendChild(password);
+
+      let foundForcer = false;
+      var observer = SpecialPowers.wrapCallback(function (
+        subject,
+        topic,
+        data
+      ) {
+        if (data === "observerforcer") {
+          foundForcer = true;
+        } else {
+          existingPasswordFieldsCount--;
+        }
+
+        if (!foundForcer || existingPasswordFieldsCount > 0) {
+          return;
+        }
+
+        SpecialPowers.removeObserver(observer, "passwordmgr-processed-form");
+        form.remove();
+        SimpleTest.executeSoon(() => {
+          callback?.();
+          resolve();
+        });
+      });
+      SpecialPowers.addObserver(observer, "passwordmgr-processed-form");
+
+      document.body.appendChild(form);
+    }
+    // We provide a general mechanism for our tests to know when they can
+    // safely run: we add a final form that we know will be filled in, wait
+    // for the login manager to tell us that it's filled in and then continue
+    // with the rest of the tests.
+    if (
+      document.readyState == "complete" ||
+      document.readyState == "interactive"
+    ) {
+      onDOMContentLoaded();
+    } else {
+      window.addEventListener("DOMContentLoaded", onDOMContentLoaded);
+    }
+  });
+}
+
+function enablePrimaryPassword() {
+  setPrimaryPassword(true);
+}
+
+function disablePrimaryPassword() {
+  setPrimaryPassword(false);
+}
+
+function setPrimaryPassword(enable) {
+  PWMGR_COMMON_PARENT.sendAsyncMessage("setPrimaryPassword", { enable });
+}
+
+function isLoggedIn() {
+  return PWMGR_COMMON_PARENT.sendQuery("isLoggedIn");
+}
+
+function logoutPrimaryPassword() {
+  runInParent(function parent_logoutPrimaryPassword() {
+    var sdr = Cc["@mozilla.org/security/sdr;1"].getService(
+      Ci.nsISecretDecoderRing
+    );
+    sdr.logoutAndTeardown();
+  });
+}
+
+/**
+ * Resolves when a specified number of forms have been processed for (potential) filling.
+ * This relies on the observer service which only notifies observers within the same process.
+ */
+function promiseFormsProcessedInSameProcess(expectedCount = 1) {
+  var processedCount = 0;
+  return new Promise((resolve, reject) => {
+    function onProcessedForm(subject, topic, data) {
+      processedCount++;
+      if (processedCount == expectedCount) {
+        info(`${processedCount} form(s) processed`);
+        SpecialPowers.removeObserver(
+          onProcessedForm,
+          "passwordmgr-processed-form"
+        );
+        resolve(SpecialPowers.Cu.waiveXrays(subject), data);
+      }
+    }
+    SpecialPowers.addObserver(onProcessedForm, "passwordmgr-processed-form");
+  });
+}
+
+/**
+ * Resolves when a form has been processed for (potential) filling.
+ * This works across processes.
+ */
+async function promiseFormsProcessed(expectedCount = 1) {
+  info(`waiting for ${expectedCount} forms to be processed`);
+  var processedCount = 0;
+  return new Promise(resolve => {
+    PWMGR_COMMON_PARENT.addMessageListener(
+      "formProcessed",
+      function formProcessed() {
+        processedCount++;
+        info(`processed form ${processedCount} of ${expectedCount}`);
+        if (processedCount == expectedCount) {
+          info(`processing of ${expectedCount} forms complete`);
+          PWMGR_COMMON_PARENT.removeMessageListener(
+            "formProcessed",
+            formProcessed
+          );
+          resolve();
+        }
+      }
+    );
+  });
+}
+
+async function loadFormIntoWindow(origin, html, win, expectedCount = 1, task) {
+  let loadedPromise = new Promise(resolve => {
+    win.addEventListener(
+      "load",
+      function (event) {
+        if (event.target.location.href.endsWith("blank.html")) {
+          resolve();
+        }
+      },
+      { once: true }
+    );
+  });
+
+  let processedPromise = promiseFormsProcessed(expectedCount);
+  win.location =
+    origin + "/tests/toolkit/components/passwordmgr/test/mochitest/blank.html";
+  info(`Waiting for window to load for origin: ${origin}`);
+  await loadedPromise;
+
+  await SpecialPowers.spawn(
+    win,
+    [html, task?.toString()],
+    function (contentHtml, contentTask = null) {
+      this.content.document.documentElement.innerHTML = contentHtml;
+      // Similar to the invokeContentTask helper in accessible/tests/browser/shared-head.js
+      if (contentTask) {
+        // eslint-disable-next-line no-eval
+        const runnableTask = eval(`
+      (() => {
+        return (${contentTask});
+      })();`);
+        runnableTask.call(this);
+      }
+    }
+  );
+
+  info("Waiting for the form to be processed");
+  await processedPromise;
+}
+
+async function getTelemetryEvents(options) {
+  let events = await PWMGR_COMMON_PARENT.sendQuery(
+    "getTelemetryEvents",
+    options
+  );
+  info("CONTENT: getTelemetryEvents gotResult: " + JSON.stringify(events));
+  return events;
+}
+
+function loadRecipes(recipes) {
+  info("Loading recipes");
+  return PWMGR_COMMON_PARENT.sendQuery("loadRecipes", recipes);
+}
+
+function resetRecipes() {
+  info("Resetting recipes");
+  return PWMGR_COMMON_PARENT.sendQuery("resetRecipes");
+}
+
+async function promiseStorageChanged(expectedChangeTypes) {
+  let result = await PWMGR_COMMON_PARENT.sendQuery("storageChanged", {
+    expectedChangeTypes,
+  });
+
+  if (result) {
+    ok(false, result);
+  }
+}
+
+async function promisePromptShown(expectedTopic) {
+  let topic = await PWMGR_COMMON_PARENT.sendQuery("promptShown");
+  is(topic, expectedTopic, "Check expected prompt topic");
+}
+
+/**
+ * Run a function synchronously in the parent process and destroy it in the test cleanup function.
+ * @param {Function|String} aFunctionOrURL - either a function that will be stringified and run
+ *                                           or the URL to a JS file.
+ * @return {Object} - the return value of loadChromeScript providing message-related methods.
+ *                    @see loadChromeScript in specialpowersAPI.js
+ */
+function runInParent(aFunctionOrURL) {
+  let chromeScript = SpecialPowers.loadChromeScript(aFunctionOrURL);
+  SimpleTest.registerCleanupFunction(() => {
+    chromeScript.destroy();
+  });
+  return chromeScript;
+}
+
+/** Manage logins in parent chrome process.
+ * */
+function manageLoginsInParent() {
+  return runInParent(function addLoginsInParentInner() {
+    /* eslint-env mozilla/chrome-script */
+    addMessageListener("removeAllUserFacingLogins", () => {
+      Services.logins.removeAllUserFacingLogins();
+    });
+
+    /* eslint-env mozilla/chrome-script */
+    addMessageListener("getLogins", async () => {
+      const logins = await Services.logins.getAllLogins();
+      return logins.map(
+        ({
+          origin,
+          formActionOrigin,
+          httpRealm,
+          username,
+          password,
+          usernameField,
+          passwordField,
+        }) => [
+          origin,
+          formActionOrigin,
+          httpRealm,
+          username,
+          password,
+          usernameField,
+          passwordField,
+        ]
+      );
+    });
+
+    /* eslint-env mozilla/chrome-script */
+    addMessageListener("addLogins", async logins => {
+      let nsLoginInfo = Components.Constructor(
+        "@mozilla.org/login-manager/loginInfo;1",
+        Ci.nsILoginInfo,
+        "init"
+      );
+
+      const loginInfos = logins.map(login => new nsLoginInfo(...login));
+      try {
+        await Services.logins.addLogins(loginInfos);
+      } catch (e) {
+        assert.ok(false, "addLogins threw: " + e);
+      }
+    });
+  });
+}
+
+/** Initialize with a list of logins. The logins are added within the parent chrome process.
+ * @param {array} aLogins - a list of logins to add. Each login is an array of the arguments
+ *                          that would be passed to nsLoginInfo.init().
+ */
+async function addLoginsInParent(...aLogins) {
+  const script = manageLoginsInParent();
+  await script.sendQuery("addLogins", aLogins);
+  return script;
+}
+
+/** Initialize with a list of logins, after removing all user facing logins.
+ * The logins are added within the parent chrome process.
+ * @param {array} aLogins - a list of logins to add. Each login is an array of the arguments
+ *                          that would be passed to nsLoginInfo.init().
+ */
+async function setStoredLoginsAsync(...aLogins) {
+  const script = manageLoginsInParent();
+  script.sendQuery("removeAllUserFacingLogins");
+  await script.sendQuery("addLogins", aLogins);
+  return script;
+}
+
+/**
+ * Sets given logins for the duration of the test. Existing logins are first
+ * removed and finally restored when the test is finished.
+ * The logins are added within the parent chrome process.
+ * @param {array} logins - a list of logins to add. Each login is an array of the arguments
+ *                          that would be passed to nsLoginInfo.init().
+ */
+async function setStoredLoginsDuringTest(...logins) {
+  const script = manageLoginsInParent();
+  const loginsBefore = await script.sendQuery("getLogins");
+  await script.sendQuery("removeAllUserFacingLogins");
+  await script.sendQuery("addLogins", logins);
+  SimpleTest.registerCleanupFunction(async () => {
+    await script.sendQuery("removeAllUserFacingLogins");
+    await script.sendQuery("addLogins", loginsBefore);
+  });
+}
+
+/**
+ * Sets given logins for the duration of the task. Existing logins are first
+ * removed and finally restored when the task is finished.
+ * @param {array} logins - a list of logins to add. Each login is an array of the arguments
+ *                          that would be passed to nsLoginInfo.init().
+ */
+async function setStoredLoginsDuringTask(...logins) {
+  const script = manageLoginsInParent();
+  const loginsBefore = await script.sendQuery("getLogins");
+  await script.sendQuery("removeAllUserFacingLogins");
+  await script.sendQuery("addLogins", logins);
+  SimpleTest.registerTaskCleanupFunction(async () => {
+    await script.sendQuery("removeAllUserFacingLogins");
+    await script.sendQuery("addLogins", loginsBefore);
+  });
+}
+
+/** Returns a promise which resolves to a list of logins
+ */
+function getLogins() {
+  const script = manageLoginsInParent();
+  return script.sendQuery("getLogins");
+}
+
+/*
+ * gTestDependsOnDeprecatedLogin Set this global to true if your test relies
+ * on the testuser/testpass login that is created in pwmgr_common.js. New tests
+ * should not rely on this login.
+ */
+var gTestDependsOnDeprecatedLogin = false;
+
+/**
+ * Replace the content innerHTML with the provided form and wait for autofill to fill in the form.
+ *
+ * @param {string} form The form to be appended to the #content element.
+ * @param {string} fieldSelector The CSS selector for the field to-be-filled
+ * @param {string} fieldValue The value expected to be filled
+ * @param {string} formId The ID (excluding the # character) of the form
+ */
+function setFormAndWaitForFieldFilled(
+  form,
+  { fieldSelector, fieldValue, formId }
+) {
+  document.querySelector("#content").innerHTML = form;
+  return SimpleTest.promiseWaitForCondition(() => {
+    let ancestor = formId
+      ? document.querySelector("#" + formId)
+      : document.documentElement;
+    return ancestor.querySelector(fieldSelector).value == fieldValue;
+  }, "Wait for password manager to fill form");
+}
+
+/**
+ * Run commonInit synchronously in the parent then run the test function if supplied.
+ *
+ * @param {Function} aFunction The test function to run
+ */
+async function runChecksAfterCommonInit(aFunction = null) {
+  SimpleTest.waitForExplicitFinish();
+  await PWMGR_COMMON_PARENT.sendQuery("setupParent", {
+    testDependsOnDeprecatedLogin: gTestDependsOnDeprecatedLogin,
+  });
+
+  if (aFunction) {
+    await registerRunTests(0, aFunction);
+  }
+
+  return PWMGR_COMMON_PARENT;
+}
+
+// Begin code that runs immediately for all tests that include this file.
+
+const PWMGR_COMMON_PARENT = runInParent(
+  SimpleTest.getTestFileURL("pwmgr_common_parent.js")
+);
+
+SimpleTest.registerCleanupFunction(() => {
+  SpecialPowers.flushPrefEnv();
+
+  PWMGR_COMMON_PARENT.sendAsyncMessage("cleanup");
+
+  runInParent(function cleanupParent() {
+    /* eslint-env mozilla/chrome-script */
+    // eslint-disable-next-line no-shadow
+    const { LoginManagerParent } = ChromeUtils.importESModule(
+      "resource://gre/modules/LoginManagerParent.sys.mjs"
+    );
+
+    // Remove all logins and disabled hosts
+    Services.logins.removeAllUserFacingLogins();
+
+    let disabledHosts = Services.logins.getAllDisabledHosts();
+    disabledHosts.forEach(host =>
+      Services.logins.setLoginSavingEnabled(host, true)
+    );
+
+    let authMgr = Cc["@mozilla.org/network/http-auth-manager;1"].getService(
+      Ci.nsIHttpAuthManager
+    );
+    authMgr.clearAll();
+
+    // Check that it's not null, instead of truthy to catch it becoming undefined
+    // in a refactoring.
+    if (LoginManagerParent._recipeManager !== null) {
+      LoginManagerParent._recipeManager.reset();
+    }
+
+    // Cleanup PopupNotifications (if on a relevant platform)
+    let chromeWin = Services.wm.getMostRecentWindow("navigator:browser");
+    if (chromeWin && chromeWin.PopupNotifications) {
+      let notes = chromeWin.PopupNotifications._currentNotifications;
+      if (notes.length) {
+        dump("Removing " + notes.length + " popup notifications.\n");
+      }
+      for (let note of notes) {
+        note.remove();
+      }
+    }
+
+    // Clear events last in case the above cleanup records events.
+    Services.telemetry.clearEvents();
+  });
+});
+
+/**
+ * Proxy for Services.logins (nsILoginManager).
+ * Only supports arguments which support structured clone plus {nsILoginInfo}
+ * Assumes properties are methods.
+ */
+this.LoginManager = new Proxy(
+  {},
+  {
+    get(target, prop, receiver) {
+      return (...args) => {
+        let loginInfoIndices = [];
+        let cloneableArgs = args.map((val, index) => {
+          if (
+            SpecialPowers.call_Instanceof(val, SpecialPowers.Ci.nsILoginInfo)
+          ) {
+            loginInfoIndices.push(index);
+            return LoginHelper.loginToVanillaObject(val);
+          }
+
+          return val;
+        });
+
+        return PWMGR_COMMON_PARENT.sendQuery("proxyLoginManager", {
+          args: cloneableArgs,
+          loginInfoIndices,
+          methodName: prop,
+        });
+      };
+    },
+  }
+);
+
+/**
+ * Set the inner html of the content div and ensure it gets reset after current
+ * task finishes.
+ * Returns the first child node of the newly created content div for convenient
+ * access of the newly created dom node.
+ *
+ * @param {String} html
+ *        string of dom content or dom element to be inserted into content element
+ */
+function setContentForTask(html) {
+  const content = document.querySelector("#content");
+  const innerHTMLBefore = content.innerHTML || "";
+  SimpleTest.registerCurrentTaskCleanupFunction(
+    () => (content.innerHTML = innerHTMLBefore)
+  );
+  if (html.content?.cloneNode) {
+    const clone = html.content.cloneNode(true);
+    content.replaceChildren(clone);
+  } else {
+    content.innerHTML = html;
+  }
+  return content.firstElementChild;
+}
+
+/*
+ * Set preferences via SpecialPowers.pushPrefEnv and reset them after current
+ * task has finished.
+ *
+ * @param {*Object} preferences
+ * */
+async function setPreferencesForTask(...preferences) {
+  await SpecialPowers.pushPrefEnv({
+    set: preferences,
+  });
+  SimpleTest.registerCurrentTaskCleanupFunction(() => SpecialPowers.popPrefEnv);
+}
+
+// capture form autofill results between tasks
+let gPwmgrCommonCapturedAutofillResults = {};
+PWMGR_COMMON_PARENT.addMessageListener(
+  "formProcessed",
+  ({ formId, autofillResult }) => {
+    if (formId === "observerforcer") {
+      return;
+    }
+
+    gPwmgrCommonCapturedAutofillResults[formId] = autofillResult;
+  }
+);
+SimpleTest.registerTaskCleanupFunction(() => {
+  gPwmgrCommonCapturedAutofillResults = {};
+});
+
+/**
+ * Create a promise that resolves when the form has been processed.
+ * Works with forms processed in the past since the task started and in the future,
+ * across parent and child processes.
+ *
+ * @param {String} formId / the id of the form of which to expect formautofill events
+ * @returns promise, resolving with the autofill result.
+ */
+async function formAutofillResult(formId) {
+  if (formId in gPwmgrCommonCapturedAutofillResults) {
+    const autofillResult = gPwmgrCommonCapturedAutofillResults[formId];
+    delete gPwmgrCommonCapturedAutofillResults[formId];
+    return autofillResult;
+  }
+  return new Promise((resolve, reject) => {
+    PWMGR_COMMON_PARENT.addMessageListener(
+      "formProcessed",
+      ({ formId: id, autofillResult }) => {
+        if (id !== formId) {
+          return;
+        }
+        delete gPwmgrCommonCapturedAutofillResults[formId];
+        resolve(autofillResult);
+      },
+      { once: true }
+    );
+  });
+}
diff --git a/toolkit/components/passwordmgr/test/mochitest/pwmgr_common_parent.js b/toolkit/components/passwordmgr/test/mochitest/pwmgr_common_parent.js
new file mode 100644
index 0000000000..09ad80f467
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/pwmgr_common_parent.js
@@ -0,0 +1,247 @@
+/**
+ * Loaded as a frame script to do privileged things in mochitest-plain tests.
+ * See pwmgr_common.js for the content process companion.
+ */
+
+/* eslint-env mozilla/chrome-script */
+
+"use strict";
+
+var { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+var { LoginHelper } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginHelper.sys.mjs"
+);
+var { LoginManagerParent } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerParent.sys.mjs"
+);
+const { LoginTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/LoginTestUtils.sys.mjs"
+);
+if (LoginHelper.relatedRealmsEnabled) {
+  let rsPromise =
+    LoginTestUtils.remoteSettings.setupWebsitesWithSharedCredentials();
+  async () => {
+    await rsPromise;
+  };
+}
+if (LoginHelper.improvedPasswordRulesEnabled) {
+  let rsPromise = LoginTestUtils.remoteSettings.setupImprovedPasswordRules({
+    rules: "",
+  });
+  async () => {
+    await rsPromise;
+  };
+}
+
+/**
+ * Init with a common login.
+ */
+async function commonInit(testDependsOnDeprecatedLogin) {
+  var pwmgr = Services.logins;
+  assert.ok(pwmgr != null, "Access LoginManager");
+
+  // Check that initial state has no logins
+  var logins = await pwmgr.getAllLogins();
+  assert.equal(logins.length, 0, "Not expecting logins to be present");
+  var disabledHosts = pwmgr.getAllDisabledHosts();
+  if (disabledHosts.length) {
+    assert.ok(false, "Warning: wasn't expecting disabled hosts to be present.");
+    for (var host of disabledHosts) {
+      pwmgr.setLoginSavingEnabled(host, true);
+    }
+  }
+
+  if (testDependsOnDeprecatedLogin) {
+    // Add a login that's used in multiple tests
+    var login = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(
+      Ci.nsILoginInfo
+    );
+    login.init(
+      "http://mochi.test:8888",
+      "http://mochi.test:8888",
+      null,
+      "testuser",
+      "testpass",
+      "uname",
+      "pword"
+    );
+    await pwmgr.addLoginAsync(login);
+  }
+
+  // Last sanity check
+  logins = await pwmgr.getAllLogins();
+  assert.equal(
+    logins.length,
+    testDependsOnDeprecatedLogin ? 1 : 0,
+    "Checking for successful init login"
+  );
+  disabledHosts = pwmgr.getAllDisabledHosts();
+  assert.equal(disabledHosts.length, 0, "Checking for no disabled hosts");
+}
+
+async function dumpLogins() {
+  let logins = await Services.logins.getAllLogins();
+  assert.ok(true, "----- dumpLogins: have " + logins.length + " logins. -----");
+  for (var i = 0; i < logins.length; i++) {
+    dumpLogin("login #" + i + " --- ", logins[i]);
+  }
+}
+
+function dumpLogin(label, login) {
+  var loginText = "";
+  loginText += "origin: ";
+  loginText += login.origin;
+  loginText += " / formActionOrigin: ";
+  loginText += login.formActionOrigin;
+  loginText += " / realm: ";
+  loginText += login.httpRealm;
+  loginText += " / user: ";
+  loginText += login.username;
+  loginText += " / pass: ";
+  loginText += login.password;
+  loginText += " / ufield: ";
+  loginText += login.usernameField;
+  loginText += " / pfield: ";
+  loginText += login.passwordField;
+  assert.ok(true, label + loginText);
+}
+
+addMessageListener("storageChanged", async function ({ expectedChangeTypes }) {
+  return new Promise((resolve, reject) => {
+    function storageChanged(subject, topic, data) {
+      let changeType = expectedChangeTypes.shift();
+      if (data != changeType) {
+        resolve("Unexpected change type " + data + ", expected " + changeType);
+      } else if (expectedChangeTypes.length === 0) {
+        Services.obs.removeObserver(
+          storageChanged,
+          "passwordmgr-storage-changed"
+        );
+        resolve();
+      }
+    }
+
+    Services.obs.addObserver(storageChanged, "passwordmgr-storage-changed");
+  });
+});
+
+addMessageListener("promptShown", async function () {
+  return new Promise(resolve => {
+    function promptShown(subject, topic, data) {
+      Services.obs.removeObserver(promptShown, "passwordmgr-prompt-change");
+      Services.obs.removeObserver(promptShown, "passwordmgr-prompt-save");
+      resolve(topic);
+    }
+
+    Services.obs.addObserver(promptShown, "passwordmgr-prompt-change");
+    Services.obs.addObserver(promptShown, "passwordmgr-prompt-save");
+  });
+});
+
+addMessageListener("cleanup", () => {
+  Services.logins.removeAllUserFacingLogins();
+});
+
+// Begin message listeners
+
+addMessageListener(
+  "setupParent",
+  async ({ testDependsOnDeprecatedLogin = false } = {}) => {
+    return commonInit(testDependsOnDeprecatedLogin);
+  }
+);
+
+addMessageListener("loadRecipes", async function (recipes) {
+  var recipeParent = await LoginManagerParent.recipeParentPromise;
+  await recipeParent.load(recipes);
+  return recipes;
+});
+
+addMessageListener("resetRecipes", async function () {
+  let recipeParent = await LoginManagerParent.recipeParentPromise;
+  await recipeParent.reset();
+});
+
+addMessageListener("getTelemetryEvents", options => {
+  options = Object.assign(
+    {
+      filterProps: {},
+      clear: false,
+    },
+    options
+  );
+  let snapshots = Services.telemetry.snapshotEvents(
+    Ci.nsITelemetry.DATASET_PRERELEASE_CHANNELS,
+    options.clear
+  );
+  let events = options.process in snapshots ? snapshots[options.process] : [];
+
+  // event is array of values like: [22476,"pwmgr","autocomplete_field","generatedpassword"]
+  let keys = ["id", "category", "method", "object", "value"];
+  events = events.filter(entry => {
+    for (let idx = 0; idx < keys.length; idx++) {
+      let key = keys[idx];
+      if (
+        key in options.filterProps &&
+        options.filterProps[key] !== entry[idx]
+      ) {
+        return false;
+      }
+    }
+    return true;
+  });
+
+  return events;
+});
+
+addMessageListener("proxyLoginManager", async msg => {
+  // Recreate nsILoginInfo objects from vanilla JS objects.
+  let recreatedArgs = msg.args.map((arg, index) => {
+    if (msg.loginInfoIndices.includes(index)) {
+      return LoginHelper.vanillaObjectToLogin(arg);
+    }
+
+    return arg;
+  });
+
+  let rv = await Services.logins[msg.methodName](...recreatedArgs);
+  if (rv instanceof Ci.nsILoginInfo) {
+    rv = LoginHelper.loginToVanillaObject(rv);
+  } else if (
+    Array.isArray(rv) &&
+    !!rv.length &&
+    rv[0] instanceof Ci.nsILoginInfo
+  ) {
+    rv = rv.map(login => LoginHelper.loginToVanillaObject(login));
+  }
+  return rv;
+});
+
+addMessageListener("isLoggedIn", () => {
+  // This can't use the LoginManager proxy in pwmgr_common.js since it's not a method.
+  return Services.logins.isLoggedIn;
+});
+
+addMessageListener("setPrimaryPassword", ({ enable }) => {
+  if (enable) {
+    LoginTestUtils.primaryPassword.enable();
+  } else {
+    LoginTestUtils.primaryPassword.disable();
+  }
+});
+
+LoginManagerParent.setListenerForTests((msg, { origin, data }) => {
+  if (msg == "ShowDoorhanger") {
+    sendAsyncMessage("formSubmissionProcessed", { origin, data });
+  } else if (msg == "PasswordEditedOrGenerated") {
+    sendAsyncMessage("passwordEditedOrGenerated", { origin, data });
+  } else if (msg == "FormProcessed") {
+    sendAsyncMessage("formProcessed", data);
+  }
+});
+
+addMessageListener("cleanup", () => {
+  LoginManagerParent.setListenerForTests(null);
+});
diff --git a/toolkit/components/passwordmgr/test/mochitest/slow_image.html b/toolkit/components/passwordmgr/test/mochitest/slow_image.html
new file mode 100644
index 0000000000..172d592633
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/slow_image.html
@@ -0,0 +1,9 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="utf-8">
+  </head>
+  <body>
+    <img src="slow_image.sjs" />
+  </body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/slow_image.sjs b/toolkit/components/passwordmgr/test/mochitest/slow_image.sjs
new file mode 100644
index 0000000000..b955e43f5d
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/slow_image.sjs
@@ -0,0 +1,25 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+// The delay time will not impact test running time, as the test does
+// not wait for the "load" event. We just need to ensure the pwmgr code
+// e.g. autofill happens before the delay time elapses.
+const DELAY_MS = "5000";
+
+let timer;
+
+function handleRequest(req, resp) {
+  resp.processAsync();
+  resp.setHeader("Cache-Control", "no-cache", false);
+  resp.setHeader("Content-Type", "image/png", false);
+
+  timer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
+  timer.init(
+    () => {
+      resp.write("");
+      resp.finish();
+    },
+    DELAY_MS,
+    Ci.nsITimer.TYPE_ONE_SHOT
+  );
+}
diff --git a/toolkit/components/passwordmgr/test/mochitest/subtst_prefilled_form.html b/toolkit/components/passwordmgr/test/mochitest/subtst_prefilled_form.html
new file mode 100644
index 0000000000..8a3e0b0240
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/subtst_prefilled_form.html
@@ -0,0 +1,18 @@
+<!DOCTYPE html><html><head><meta charset="utf-8"></head><body>
+<!-- Any copyright is dedicated to the Public Domain.
+   - http://creativecommons.org/publicdomain/zero/1.0/ -->
+
+<!-- Form with username and password fields pre-populated.
+     With a couple elements where .defaultValue !== .value -->
+<form id="form-basic">
+  <input id="form-basic-username" name="username" value="user">
+  <input id="form-basic-password" name="password" type="password" value="pass">
+  <select name="picker">
+  	<option value="foo">0</option>
+  	<option value="bar" selected>1</option>
+  </select>
+  <input id="form-basic-submit" type="submit">
+  <button id="form-basic-reset" type="reset">Reset</button>
+</form>
+
+</body></html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/subtst_primary_pass.html b/toolkit/components/passwordmgr/test/mochitest/subtst_primary_pass.html
new file mode 100644
index 0000000000..dc892c50e2
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/subtst_primary_pass.html
@@ -0,0 +1,8 @@
+<h2>MP subtest</h2>
+This form triggers a MP and gets filled in.<br>
+<form>
+Username: <input type="text"     id="userfield" name="u"><br>
+Password: <input type="password" id="passfield" name="p"
+                 oninput="parent.postMessage('filled', '*');"><br>
+</form>
+<iframe></iframe>
diff --git a/toolkit/components/passwordmgr/test/mochitest/subtst_prompt_async.html b/toolkit/components/passwordmgr/test/mochitest/subtst_prompt_async.html
new file mode 100644
index 0000000000..39a72add56
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/subtst_prompt_async.html
@@ -0,0 +1,12 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Multiple auth request</title>
+</head>
+<body>
+  <iframe id="iframe1" src="authenticate.sjs?r=1&user=user3name&pass=user3pass&realm=mochirealm3&proxy_user=proxy_user2&proxy_pass=proxy_pass2&proxy_realm=proxy_realm2"></iframe>
+  <iframe id="iframe2" src="authenticate.sjs?r=2&user=user3name&pass=user3pass&realm=mochirealm3&proxy_user=proxy_user2&proxy_pass=proxy_pass2&proxy_realm=proxy_realm2"></iframe>
+  <iframe id="iframe3" src="authenticate.sjs?r=3&user=user3name&pass=user3pass&realm=mochirealm3&proxy_user=proxy_user2&proxy_pass=proxy_pass2&proxy_realm=proxy_realm2"></iframe>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_DOMInputPasswordAdded_fired_between_DOMContentLoaded_and_load_events.html b/toolkit/components/passwordmgr/test/mochitest/test_DOMInputPasswordAdded_fired_between_DOMContentLoaded_and_load_events.html
new file mode 100644
index 0000000000..3ab40e92af
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_DOMInputPasswordAdded_fired_between_DOMContentLoaded_and_load_events.html
@@ -0,0 +1,61 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test the password manager code called on DOMInputPasswordAdded runs when it occurs between DOMContentLoaded and load events</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+  <!-- In cases where the "DOMContentLoaded" event for a page has occured but not the "load" event when
+  "DOMInputPasswordAdded" fires, we want to make sure that the Password Manager code (i.e.
+  _fetchLoginsFromParentAndFillForm) still runs on the page.
+  This scenario can happen for example when a page has very little initial HTML, but extensive JS that
+  adds Custom Elements or other HTML later, or when other subresources, like images, take a while to load.
+  In this test, we delay the page load with a delayed response for an image source. -->
+<script type="application/javascript">
+
+let DEFAULT_ORIGIN = window.location.origin;
+let FILE_PATH = "/tests/toolkit/components/passwordmgr/test/mochitest/slow_image.html";
+
+async function openDocumentInWindow(win) {
+  let DOMContentLoadedPromise = new Promise((resolve) => {
+    win.addEventListener("DOMContentLoaded", function() {
+      resolve();
+    }, {once: true});
+  });
+  win.location = DEFAULT_ORIGIN + FILE_PATH;
+  await DOMContentLoadedPromise;
+}
+
+add_setup(async () => {
+  await setStoredLoginsAsync([DEFAULT_ORIGIN, DEFAULT_ORIGIN, null, "user", "omgsecret!"]);
+});
+
+add_task(async function test_password_autofilled() {
+  let numLogins = await LoginManager.countLogins(DEFAULT_ORIGIN, DEFAULT_ORIGIN, null);
+  is(numLogins, 1, "Correct number of logins");
+
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await openDocumentInWindow(win);
+  let processedPromise = promiseFormsProcessed();
+  await SpecialPowers.spawn(win, [], function() {
+    let doc = this.content.document;
+    info("Adding password input field to the page to trigger DOMInputPasswordAdded");
+    let passwordField = doc.createElement("input");
+    passwordField.type = "password";
+    is(doc.readyState, "interactive", "Make sure 'DOMContentLoaded' has fired but not 'load'");
+    doc.body.append(passwordField);
+  });
+  info("Waiting for the password field to be autofilled");
+  await processedPromise;
+  let expectedValue = "omgsecret!";
+  await SpecialPowers.spawn(win, [expectedValue], expectedValueF => {
+    is(this.content.document.querySelector("input[type='password']").value, expectedValueF, "Ensure the password field is autofilled");
+  });
+});
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_LoginManagerContent_passwordEditedOrGenerated.html b/toolkit/components/passwordmgr/test/mochitest/test_LoginManagerContent_passwordEditedOrGenerated.html
new file mode 100644
index 0000000000..9d23177924
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_LoginManagerContent_passwordEditedOrGenerated.html
@@ -0,0 +1,160 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test behavior of unmasking in LMC._passwordEditedOrGenerated</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test"></pre>
+<script>
+const { LoginManagerChild } = SpecialPowers.ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerChild.sys.mjs"
+);
+
+function preventDefaultAndStopProgagation(event) {
+  event.preventDefault();
+  event.stopImmediatePropagation();
+}
+
+add_setup(async () => {
+  await SpecialPowers.pushPrefEnv({"set": [
+    ["signon.generation.available", true],
+    ["signon.generation.enabled", true],
+  ]});
+  await setStoredLoginsAsync(
+    [location.origin, "https://autofill", null, "user1", "pass1"],
+    [location.origin, "https://autofill", null, "user2", "pass2"]
+  );
+});
+
+add_task(async function prevent_default_and_stop_propagation() {
+  const form = createLoginForm({
+    action: "https://autofill"
+  });
+  await promiseFormsProcessedInSameProcess();
+  form.pword.focus();
+
+  form.pword.addEventListener("focus", preventDefaultAndStopProgagation);
+  form.pword.addEventListener("focus", preventDefaultAndStopProgagation, true);
+  form.pword.addEventListener("blur", preventDefaultAndStopProgagation);
+  form.pword.addEventListener("blur", preventDefaultAndStopProgagation, true);
+
+  SpecialPowers.wrap(form.pword).setUserInput("generatedpass");
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "Before first fill");
+  LoginManagerChild.forWindow(window)._passwordEditedOrGenerated(form.pword, { triggeredByFillingGenerated: true });
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, false, "After first fill");
+  synthesizeKey("KEY_Tab"); // blur
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "After blur");
+  synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, false, "After shift-tab to focus again");
+});
+
+add_task(async function fields_masked_after_saved_login_fill() {
+  const form = createLoginForm({
+    action: "https://autofill"
+  });
+  await promiseFormsProcessedInSameProcess();
+  form.pword.focus();
+
+  SpecialPowers.wrap(form.pword).setUserInput("generatedpass");
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "Before first fill");
+  LoginManagerChild.forWindow(window)._passwordEditedOrGenerated(form.pword, { triggeredByFillingGenerated: true });
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, false, "After first fill");
+  synthesizeKey("KEY_Tab", { shiftKey: true }); // blur pw, focus un
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "After blur");
+
+  info("Filling username matching saved login");
+  sendString("user1");
+
+  let processedPromise = promiseFormsProcessedInSameProcess();
+  synthesizeKey("KEY_Tab"); // focus again and trigger a fill of the matching password
+  await processedPromise;
+  is(form.pword.value, "pass1", "Saved password was filled")
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "After filling a saved login");
+});
+
+add_task(async function fields_masked_after_replacing_whole_value() {
+  const form = createLoginForm({
+    action: "https://autofill"
+  });
+  await promiseFormsProcessedInSameProcess();
+  form.pword.focus();
+
+  SpecialPowers.wrap(form.pword).setUserInput("generatedpass");
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "Before first fill");
+  LoginManagerChild.forWindow(window)._passwordEditedOrGenerated(form.pword, { triggeredByFillingGenerated: true });
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, false, "After first fill");
+  synthesizeKey("KEY_Tab", { shiftKey: true }); // blur pw, focus un
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "After blur");
+
+  synthesizeKey("KEY_Tab"); // focus again and replace the whole password value
+  info("Replacing password field value with arbitrary string");
+  sendString("some_other_password");
+  is(form.pword.value, "some_other_password", "Whole password replaced")
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "Replaced password value");
+
+  synthesizeKey("KEY_Tab"); // blur pw
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "After blur");
+  synthesizeKey("KEY_Tab", { shiftKey: true }); // focus pw again
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "After focus again");
+});
+
+add_task(async function fields_unmasked_after_adding_character() {
+  const form = createLoginForm({
+    action: "https://autofill"
+  });
+  await promiseFormsProcessedInSameProcess();
+  form.pword.focus();
+
+  SpecialPowers.wrap(form.pword).setUserInput("generatedpass");
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "Before first fill");
+  LoginManagerChild.forWindow(window)._passwordEditedOrGenerated(form.pword, { triggeredByFillingGenerated: true });
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, false, "After first fill");
+  synthesizeKey("KEY_Tab", { shiftKey: true }); // blur pw, focus un
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "After blur");
+
+  synthesizeKey("KEY_Tab"); // focus again
+  synthesizeKey("KEY_ArrowRight"); // Remove the selection
+  info("Adding a character to the end of the password");
+  sendString("@");
+  is(form.pword.value, "generatedpass@", "Character was added to the value")
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, false, "Added @");
+
+  synthesizeKey("KEY_Tab"); // blur pw
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "After blur after @");
+  synthesizeKey("KEY_Tab", { shiftKey: true }); // focus pw again
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, false, "After focus after @");
+});
+
+add_task(async function type_not_password() {
+  const form = createLoginForm({
+    action: "https://autofill"
+  });
+  await promiseFormsProcessedInSameProcess();
+  form.pword.focus();
+
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "Before first fill");
+  SpecialPowers.wrap(form.pword).setUserInput("generatedpass");
+  LoginManagerChild.forWindow(window)._passwordEditedOrGenerated(form.pword, { triggeredByFillingGenerated: true });
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, false, "After first fill");
+
+  // Simulate a website doing their own unmasking and re-masking
+  form.pword.type = "text";
+  await new Promise(resolve => SimpleTest.executeSoon(resolve));
+  form.pword.type = "password";
+
+  synthesizeKey("KEY_Tab"); // blur
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "After blur");
+  synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+  LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, false, "After shift-tab to focus again");
+});
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_autofill_related_realms_no_dupes.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_autofill_related_realms_no_dupes.html
new file mode 100644
index 0000000000..b229993a42
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_autofill_related_realms_no_dupes.html
@@ -0,0 +1,112 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Login Manager: Related Realms</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+Testing related realms
+
+Related realms is feature to provide login suggestion based on similar domains.
+
+Out of the scope of this feature is subdomain handling, which is already part
+of the base functionality. The intent is to cover the ebay.com/ebay.co.uk and
+all other country TLD cases where the sign in page is actually
+signin.ebay.com/signin.ebay.co.uk but credentials could have manually been
+entered for ebay.com/ebay.co.uk or automatically stored as
+signin.ebay.com/sigin.ebay.co.uk
+
+The related realms feature can be enabled via the preference
+signon.relatedRealms.enabled. It is disabled by default.
+
+This test proves that related logins show up in the autocomplete menu when
+the feature is enabled and that the related logins do not count as duplicates
+and therefore the form gets filled directly.
+
+<template id="form1-template">
+  <form id="form1" action="https://www.example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>
+</template>
+
+<script class="testbody" type="text/javascript">
+  const formTemplate = document.getElementById("form1-template");
+
+  add_setup(async () => {
+    await setStoredLoginsDuringTest(
+      ["https://example.com", "https://example.com", null, "example.com-user", "password", "uname", "pword"],
+
+      // Related domain relationship where example.com and other-example.com are in the related domains list
+      ["https://other-example.com", "https://other-example.com", null, "other-example.com-user", "password", "uname", "pword"],
+
+      // example.com and example.co.uk are related, so sub.example.co.uk is also related
+      ["https://sub.example.co.uk", "https://sub.example.co.uk", null, "sub.example.co.uk-user", "password", "uname", "pword"],
+
+      // www subdomain on same TLD
+      ["https://www.example.com", "https://www.example.com", null, "www.example.com-user", "password", "uname", "pword"],
+
+      // other subdomain on same TLD
+      ["https://sub.example.com", "https://sub.example.com", null, "sub.example.com-user", "password", "uname", "pword"],
+    );
+  });
+
+  add_named_task("with relatedRealms disabled, related logins do not show up in autocomplete menu", async () => {
+    await setPreferencesForTask(["signon.relatedRealms.enabled", false]);
+
+    const form = setContentForTask(formTemplate);
+
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+
+    // reset the form and open autocomplete popup by focusing username input
+    form.reset();
+    const results = await popupBy(() => form.uname.focus());
+    checkAutoCompleteResults(results, [
+      "example.com-user",
+      "sub.example.com-user",
+      "www.example.com-user",
+    ], window.location.host, "all logins are present and in order");
+  });
+
+  add_named_task("with relatedRealms enabled, related logins show up in autocomplete menu", async () => {
+    await setPreferencesForTask(["signon.relatedRealms.enabled", true]);
+
+    const form = setContentForTask(formTemplate);
+
+    const result = await formAutofillResult(form.id);
+    is(result, "filled", "form has been filled");
+
+    // reset the form and open autocomplete popup by focusing username input
+    form.reset();
+    const results = await popupBy(() => form.uname.focus());
+    checkAutoCompleteResults(results, [
+      "example.com-user",
+      "other-example.com-user",
+      "sub.example.co.uk-user",
+      "sub.example.com-user",
+      "www.example.com-user",
+    ], window.location.host, "all logins are present and in order");
+  });
+
+  add_named_task("even with relatedRealms enabled, related logins are not considered duplicates, so form will be filled", async () => {
+    await setPreferencesForTask(["signon.relatedRealms.enabled", true]);
+
+    const form = setContentForTask(formTemplate);
+
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+
+    is(form.uname.value, "example.com-user", "username from exact tld is filled in");
+  });
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form.html
new file mode 100644
index 0000000000..cfa695e002
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form.html
@@ -0,0 +1,935 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Login Manager: test basic login autocomplete</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="text/javascript" src="../../../../../dom/webauthn/tests/u2futil.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+Test for Login Manager: login autocomplete, with secure connection. This tests autocomplete menu items, its navigation, the selection and deletion of entries as well as sending untrusted events.
+
+This tests the login manager in a secure setting using https. A similar test file exists for using an insecure connection: test_autocomplete_basic_form_insecure.html.
+
+<template id="form1-template">
+  <form id="form1" action="https://autocomplete:8888/formtest.js">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>
+</template>
+
+<script class="testbody" type="text/javascript">
+  const formTemplate = document.getElementById("form1-template");
+
+  // Restore the form to the default state.
+  function restoreForm(form) {
+    form.uname.value = "";
+    form.pword.value = "";
+    form.uname.focus();
+  }
+
+  add_setup(async () => {
+    listenForUnexpectedPopupShown();
+  });
+
+  add_named_task("form is initially empty and popup closed", async () => {
+    const form = setContentForTask(formTemplate);
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const popupState = await getPopupState();
+    is(popupState.open, false, "Check popup is closed");
+  });
+
+  add_named_task("menuitems, telemetry events, selection and escape", async () => {
+    await setStoredLoginsDuringTask(
+      // login 0 has no username, so should be filtered out from the autocomplete list.
+      [location.origin, "https://autocomplete:8888", null, "", "pass0", "", "pword"],
+
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-3", "pass-3", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    form.uname.focus();
+    const autocompleteItems = await popupByArrowDown();
+
+    const popupState = await getPopupState();
+    is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
+
+    const expectedMenuItems = ["user-1",
+                             "user-2",
+                             "user-3"];
+    checkAutoCompleteResults(autocompleteItems, expectedMenuItems,
+                             window.location.host, "Check all menuitems are displayed correctly.");
+
+    const acEvents = await getTelemetryEvents({ process: "parent", filterProps: TelemetryFilterPropsAC, clear: true });
+    is(acEvents.length, 1, "One autocomplete event");
+    checkACTelemetryEvent(acEvents[0], form.uname, {
+      "hadPrevious": "0",
+      "login": expectedMenuItems.length + "",
+      "loginsFooter": "1"
+    });
+
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Escape");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+  });
+
+  add_named_task("select first entry", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    const popupState = await getPopupState();
+    is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
+    synthesizeKey("KEY_ArrowDown"); // first
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "pass-1", "password is set");
+  });
+
+  add_named_task("select second entry", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_ArrowDown"); // second
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("wrap around first entry", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_ArrowDown"); // second
+    synthesizeKey("KEY_ArrowDown"); // footer
+    synthesizeKey("KEY_ArrowDown"); // deselects
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "pass-1", "password is set");
+  });
+
+  add_named_task("wrap around up last entry", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowUp"); // footer
+    synthesizeKey("KEY_ArrowUp"); // last (fourth)
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("wrap around up down up up", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown"); // select first entry
+    synthesizeKey("KEY_ArrowUp"); // selects nothing!
+    synthesizeKey("KEY_ArrowUp"); // footer
+    synthesizeKey("KEY_ArrowUp"); // select last entry
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("wrap around up down up last", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowUp"); // deselects
+    synthesizeKey("KEY_ArrowUp"); // footer
+    synthesizeKey("KEY_ArrowUp"); // last entry
+    synthesizeKey("KEY_ArrowUp"); // first entry
+    synthesizeKey("KEY_ArrowUp"); // deselects
+    synthesizeKey("KEY_ArrowUp"); // footer
+    synthesizeKey("KEY_ArrowUp"); // last entry
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("fill username without autofill right", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    // Set first entry w/o triggering autocomplete
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_ArrowRight");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "", "password is empty");
+  });
+
+  add_named_task("fill username without autofill left", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    // Set first entry w/o triggering autocomplete
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_ArrowLeft");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "", "password is empty");
+  });
+
+  add_named_task("page up first", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    // Check first entry (page up)
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_ArrowDown"); // second
+    synthesizeKey("KEY_PageUp"); // first
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "pass-1", "password is set");
+  });
+
+  add_named_task("page down last", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    // Check last entry (page down)
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_PageDown"); // footer
+    synthesizeKey("KEY_ArrowUp"); // last
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("untrusted event", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+  });
+
+  add_named_task("delete", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-3", "pass-3", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+
+    // XXX tried sending character "t" before/during dropdown to test
+    // filtering, but had no luck. Seemed like the character was getting lost.
+    // Setting uname.value didn't seem to work either. This works with a human
+    // driver, so I'm not sure what's up.
+
+    // Delete the first entry (of 3), "user-1"
+    synthesizeKey("KEY_ArrowDown");
+    const numLoginsBeforeDeletion = await LoginManager.countLogins(location.origin, "https://autocomplete:8888", null);
+    is(numLoginsBeforeDeletion, 3, "Correct number of logins before deleting one");
+
+    const countChangedPromise = notifyMenuChanged(3);
+    const deletionPromise = promiseStorageChanged(["removeLogin"]);
+    // On OS X, shift-backspace and shift-delete work, just delete does not.
+    // On Win/Linux, shift-backspace does not work, delete and shift-delete do.
+    synthesizeKey("KEY_Delete", {shiftKey: true});
+    await deletionPromise;
+
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const numLoginsAfterDeletion = await LoginManager.countLogins(location.origin, "https://autocomplete:8888", null);
+    is(numLoginsAfterDeletion, 2, "Correct number of logins after deleting one");
+    await countChangedPromise;
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("delete second", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-3", "pass-3", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+
+    // Delete the second entry (of 3), "user-2"
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Delete", {shiftKey: true});
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const numLoginsAfterDeletion = await LoginManager.countLogins(location.origin, "https://autocomplete:8888", null);
+    is(numLoginsAfterDeletion, 2, "Correct number of logins after deleting one");
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-3", "username is set");
+    is(form.pword.value, "pass-3", "password is set");
+  });
+
+  add_named_task("delete last", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "user-3", "pass-3", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+
+    /* test 54 */
+    // Delete the last entry (of 3), "user-3"
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowDown");
+    const numLoginsBeforeDeletion = await LoginManager.countLogins(location.origin, "https://autocomplete:8888", null);
+    is(numLoginsBeforeDeletion, 3, "Correct number of logins before deleting one");
+    synthesizeKey("KEY_Delete", {shiftKey: true});
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const numLoginsAfterDeletion = await LoginManager.countLogins(location.origin, "https://autocomplete:8888", null);
+    is(numLoginsAfterDeletion, 2, "Correct number of logins after deleting one");
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "pass-1", "password is set");
+  });
+
+  // Tests for single-user forms for ignoring autocomplete=off */
+
+  add_named_task("default", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete2">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("password autocomplete off", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete2">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="off">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+
+    restoreForm(form);
+    await popupByArrowDown();
+
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    // value should not update just on selection
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("username autocomplete off", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete2">
+    <input type="text" name="uname" autocomplete="off">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+
+    restoreForm(form);
+    await popupByArrowDown();
+
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    // value should not update just on selection
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("form autocomplete off", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete2" autocomplete="off">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+    restoreForm(form);
+    await popupByArrowDown();
+
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    // value should not update just on selection
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("username and password autocomplete off", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete2">
+    <input type="text" name="uname" autocomplete="off">
+    <input type="password" name="pword" autocomplete="off">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+    restoreForm(form);
+    await popupByArrowDown();
+
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("changing username does not touch password", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete2">
+    <input type="text" name="uname" autocomplete="off">
+    <input type="password" name="pword" autocomplete="off">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+
+    // Test that the password field remains filled in after changing
+    // the username.
+    form.uname.focus();
+    synthesizeKey("KEY_ArrowRight");
+    synthesizeKey("X", {shiftKey: true});
+    // Trigger the 'blur' event on uname
+    form.pword.focus();
+    is(form.uname.value, "userX", "username is set");
+    is(form.pword.value, "pass", "password is set");
+  });
+
+  add_named_task("additional username field in between", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete3", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete3", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete3">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+
+    // Insert a new username field into the form. We'll then make sure
+    // that invoking the autocomplete doesn't try to fill the form.
+    const newField = document.createElement("input");
+    newField.setAttribute("type", "text");
+    newField.setAttribute("name", "uname2");
+    form.insertBefore(newField, form.pword);
+    is(newField.value, "", "Verifying empty uname2");
+  });
+
+  add_named_task("additional username field in between and form reset", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete3", null, "user", "pass", "uname", "pword"]
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete3">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+
+    // Insert a new username field into the form. We'll then make sure
+    // that invoking the autocomplete doesn't try to fill the form.
+    const newField = document.createElement("input");
+    newField.setAttribute("type", "text");
+    newField.setAttribute("name", "uname2");
+    form.insertBefore(newField, form.pword);
+
+    restoreForm(form);
+    const autocompleteItems = await popupByArrowDown();
+    checkAutoCompleteResults(autocompleteItems,
+                             ["user"],
+                             window.location.host,
+                             "Check dropdown is showing all logins while field is blank");
+
+
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    // The form changes, so we expect the old username field to get the
+    // selected autocomplete value, but neither the new username field nor
+    // the password field should have any values filled in.
+    await SimpleTest.promiseWaitForCondition(() => form.uname.value == "user",
+                                             "Wait for username to get filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "", "password is empty");
+    is(newField.value, "", "Verifying empty uname2");
+  });
+
+  add_named_task("two forms with different actions", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete", null, "user", "pass", "uname", "pword"]
+    );
+    const div = setContentForTask(`<div>
+      <form id="form1" action="https://autocomplete-other">
+        <input type="email" name="uname">
+        <input type="password" name="pword">
+      </form>
+      <form id="form2" action="https://autocomplete">
+        <input type="email" name="uname">
+        <input type="password" name="pword">
+      </form>
+    </div>`);
+    const form1 = div.querySelector("#form1");
+    const form2 = div.querySelector("#form2");
+    const autofillResult = await formAutofillResult(form1.id);
+    is(autofillResult, "no_saved_logins", "form has not been filled due to no saved logins");
+    const autofillResult2 = await formAutofillResult(form2.id);
+    is(autofillResult2, "filled", "form has been filled");
+
+    is(form2.uname.value, "user", "username is set");
+    is(form2.pword.value, "pass", "password is set");
+
+    restoreForm(form2);
+    is(form2.uname.value, "", "username is empty");
+    is(form2.pword.value, "", "password is empty");
+
+    form1.uname.focus();
+    is(form2.uname.value, "", "username is empty");
+    is(form2.pword.value, "", "password is empty");
+  });
+
+  add_named_task("filtering", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete", null, "form9userAB", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete", null, "form9userAAB", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+
+    const results = await popupBy(() => form.uname.focus());
+    checkAutoCompleteResults(results,
+                             ["form9userAAB", "form9userAB"],
+                             window.location.host,
+                             "Check dropdown is showing all logins while field is blank");
+    synthesizeKey("KEY_Escape"); // Need to close the popup so we can get another popupshown after sending the string below.
+
+    const results2 = await popupBy(() => sendString("form9userAB"));
+    checkAutoCompleteResults(results2,
+                             ["form9userAB"],
+                             window.location.host,
+                             "Check dropdown is showing login with only one 'A'");
+
+    is(form.uname.value, "form9userAB", "username is set");
+    is(form.pword.value, "", "password is empty");
+    form.uname.focus();
+    synthesizeKey("KEY_ArrowLeft");
+    const results3 = await popupBy(() => synthesizeKey("A", {shiftKey: true}));
+
+    is(form.uname.value, "form9userAAB", "username is set");
+    is(form.pword.value, "", "password is empty");
+    checkAutoCompleteResults(results3, ["form9userAAB"],
+                             window.location.host, "Check dropdown is updated after inserting 'A'");
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "form9userAAB", "username is set");
+    is(form.pword.value, "pass-2", "password set");
+  });
+
+  add_named_task("autocomplete cache", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "form9userAB", "pass-1", "uname", "pword"],
+      [location.origin, "https://autocomplete:8888", null, "form9userAAB", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+
+    await popupBy(() => form.uname.focus());
+
+    await addLoginsInParent(
+      [location.origin, "https://autocomplete", null, "form9userAABzz", "pass-3", "uname", "pword"]
+    );
+
+    const promise1 = notifyMenuChanged(1);
+    sendString("z");
+    const results1 = await promise1;
+    checkAutoCompleteResults(results1, [], window.location.host,
+                             "Check popup does not have any login items");
+
+    // check that empty results are cached - bug 496466
+    const promise2 = notifyMenuChanged(1);
+    sendString("z");
+    const results2 = await promise2;
+    checkAutoCompleteResults(results2, [], window.location.host,
+                             "Check popup only has the footer when it opens");
+  });
+
+  add_named_task("formless", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, location.origin, null, "user", "pass", "uname", "pword"]
+    );
+    const form = setContentForTask(`<form id="form1">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+
+    // Test form-less autocomplete
+    // Test form-less autocomplete
+    // TODO: wait - whats formless about this form?
+    restoreForm(form);
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("open on trusted focus", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user", "pass", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+
+    form.uname.value = "";
+    form.pword.value = "";
+
+    // Move focus to the password field so we can test the first click on the
+    // username field.
+    form.pword.focus();
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const firePrivEventPromise = new Promise((resolve) => {
+      form.uname.addEventListener("click", (e) => {
+        ok(e.isTrusted, "Ensure event is trusted");
+        resolve();
+      });
+    });
+    await popupBy(async () => {
+      synthesizeMouseAtCenter(form.uname, {});
+      await firePrivEventPromise;
+    });
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("recipes", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "user", "pass", "uname", "pword"]
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete:8888">
+    <input type="text" name="uname">
+    <input type="text" name="pword">
+  </form>`);
+
+    await loadRecipes({
+      siteRecipes: [{
+        "hosts": [window.location.host],
+        "usernameSelector": "input[name='1']",
+        "passwordSelector": "input[name='2']",
+      }],
+    });
+
+    // Switch the password field to type=password so _fillForm marks the username
+    // field for autocomplete.
+    form.pword.type = "password";
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    restoreForm(form);
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+
+    // Now test recipes with blur on the username field.
+    restoreForm(form);
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    form.uname.value = "user";
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Tab");
+    const autofillResult3 = await formAutofillResult(form.id);
+    is(autofillResult3, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+    await resetRecipes();
+  });
+
+  add_named_task("form stays open upon empty search", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete:8888", null, "", "pass", "", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete:8888">
+    <input type="text" name="uname" value="prefilled">
+    <input type="password" name="pword" value="prefilled">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "existing_password", "form has not been filled due to existing password");
+
+    is(form.uname.value, "prefilled", "username is not changed");
+    is(form.pword.value, "prefilled", "password is not changed");
+
+    form.uname.scrollIntoView();
+    await popupBy(() => synthesizeMouseAtCenter(form.uname, {}));
+    form.uname.select();
+    synthesizeKey("KEY_Delete");
+
+    const popupState = await getPopupState();
+    is(popupState.open, true, "Check popup is still open");
+    is(form.uname.value, "", "username is emoty");
+    is(form.pword.value, "prefilled", "password is not changed");
+
+    info("testing password field");
+    synthesizeMouseAtCenter(form.pword, {});
+    form.pword.select();
+    const popupState2 = await getPopupState();
+    is(popupState2.open, false, "Check popup closed since password field isn't empty");
+    await popupBy(() => synthesizeKey("KEY_Delete"));
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+  });
+
+  add_named_task("username only", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "https://autocomplete", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete" autocomplete="off">
+    <input type="email" name="uname" value="prefilled" autocomplete="username">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "existing_username", "form has not been filled due to existing username");
+
+    is(form.uname.value, "prefilled", "username is not changed");
+    is(form.pword.value, "", "password is empty");
+    restoreForm(form);
+    await popupByArrowDown();
+
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is set");
+    is(form.pword.value, "pass", "password is set");
+  });
+
+  add_named_task("webauthn", async () => {
+    await setStoredLoginsDuringTask();
+    const form = setContentForTask(`<form id="form1" action="https://autocomplete">
+    <input type="text" name="uname" autocomplete="webauthn">
+    <input type="password" name="pword" autocomplete="current-password webauthn">
+  </form>`);
+
+    // Set up a virtual authenticator with a credential for this site.
+    let authenticatorId = await addVirtualAuthenticator();
+    addCredential(authenticatorId, document.domain);
+
+    // Start a conditionally mediated WebAuthn request.
+    let challenge = crypto.getRandomValues(new Uint8Array(16));
+    let publicKey = { challenge, rpId: document.domain };
+    let webauthnPromise = navigator.credentials.get( { publicKey, mediation: "conditional" });
+
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "no_saved_logins", "form has not been filled due to no saved logins");
+
+    // Ensure that focusing on either input shows the popup
+    form.uname.focus();
+    await popupByArrowDown();
+
+    form.pword.focus();
+    await popupByArrowDown();
+
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+
+    let credential = await webauthnPromise;
+    is(credential.type, "public-key", "received a webauthn credential");
+  });
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_formActionOrigin.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_formActionOrigin.html
new file mode 100644
index 0000000000..0365d5369c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_formActionOrigin.html
@@ -0,0 +1,79 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test that logins with non-matching formActionOrigin appear in autocomplete dropdown</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+Login Manager test: logins with non-matching formActionOrigin appear in autocomplete dropdown
+
+<template id="form1-template">
+  <form id="form1">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>
+</template>
+
+<script class="testbody" type="text/javascript">
+  const formTemplate = document.getElementById("form1-template");
+
+  add_setup(async () => {
+    await setStoredLoginsDuringTest(
+      [window.location.origin, "https://differentFormSubmitURL", null, "dfsu1", "dfsp1", "uname", "pword"]
+    );
+    listenForUnexpectedPopupShown();
+  });
+
+  add_named_task("form initially empty", async () => {
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "no_saved_logins", "form has not been filled due to no saved logins");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const popupState = await getPopupState();
+    is(popupState.open, false, "Check popup is initially closed");
+  });
+
+  /* For this testcase, the only login that exists for this origin
+   * is one with a different formActionOrigin, so the login will appear
+   * in the autocomplete popup.
+   */
+  add_named_task("menu shows logins for different form action origin", async () => {
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "no_saved_logins", "form has not been filled due to no saved logins");
+
+    // Trigger autocomplete popup
+    form.uname.focus();
+
+    const autocompleteItems = await popupByArrowDown();
+
+    const popupState = await getPopupState();
+    is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
+
+    const expectedMenuItems = ["dfsu1"];
+    checkAutoCompleteResults(autocompleteItems, expectedMenuItems, window.location.host, "Check all menuitems are displayed correctly.");
+
+    synthesizeKey("KEY_ArrowDown"); // first item
+
+    // value shouldn't update just by selecting
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "dfsu1", "username is set");
+    is(form.pword.value, "dfsp1", "password is set");
+  });
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_insecure.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_insecure.html
new file mode 100644
index 0000000000..156a89f77a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_insecure.html
@@ -0,0 +1,932 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test insecure form field autocomplete</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+Test for Login Manager: login autocomplete, with insecure connection. This tests autocomplete menu items, its navigation, the selection and deletion of entries as well as sending untrusted events.
+
+This tests the login manager in a insecure setting using http. A similar test file exists for using a secure connection: test_autocomplete_basic_form.html.
+
+<template id="form1-template">
+  <form id="form1" action="http://autocomplete:8888/formtest.js">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>
+</template>
+
+<script class="testbody" type="text/javascript">
+  const formTemplate = document.getElementById("form1-template");
+
+  // Restore the form to the default state.
+  function restoreForm(form) {
+    form.uname.value = "";
+    form.pword.value = "";
+    form.uname.focus();
+  }
+
+  add_setup(async () => {
+    listenForUnexpectedPopupShown();
+  });
+
+  add_named_task("form is initially empty and popup closed", async () => {
+    const form = setContentForTask(formTemplate);
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const popupState = await getPopupState();
+    is(popupState.open, false, "Check popup is closed");
+  });
+
+  add_named_task("menuitems, telemetry events, selection and escape", async () => {
+    await setStoredLoginsDuringTask(
+      // login 0 has no username, so should be filtered out from the autocomplete list.
+      [location.origin, "http://autocomplete:8888", null, "", "pass0", "", "pword"],
+
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-3", "pass-3", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    form.uname.focus();
+    const autocompleteItems = await popupByArrowDown();
+
+    const popupState = await getPopupState();
+    is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
+
+    const expectedMenuItems = [
+      "This connection is not secure. Logins entered here could be compromised. Learn More",
+      "user-1",
+      "user-2",
+      "user-3"
+    ];
+    checkAutoCompleteResults(autocompleteItems, expectedMenuItems,
+                             window.location.host, "Check all menuitems are displayed correctly.");
+
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Escape");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+  });
+
+  add_named_task("select first entry", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    const popupState = await getPopupState();
+    is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown"); // first
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "pass-1", "password is set");
+  });
+
+  add_named_task("select second entry", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_ArrowDown"); // second
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("wrap around first entry", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_ArrowDown"); // second
+    synthesizeKey("KEY_ArrowDown"); // footer
+    synthesizeKey("KEY_ArrowDown"); // deselects
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "pass-1", "password is set");
+  });
+
+  add_named_task("wrap around up last entry", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowUp"); // footer
+    synthesizeKey("KEY_ArrowUp"); // last (fourth)
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("wrap around up down up up", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown"); // select first entry
+    synthesizeKey("KEY_ArrowUp"); // selects nothing!
+    synthesizeKey("KEY_ArrowUp"); // footer
+    synthesizeKey("KEY_ArrowUp"); // select last entry
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("wrap around up down up last", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowUp"); // deselects
+    synthesizeKey("KEY_ArrowUp"); // footer
+    synthesizeKey("KEY_ArrowUp"); // last entry
+    synthesizeKey("KEY_ArrowUp"); // skip insecure warning
+    synthesizeKey("KEY_ArrowUp"); // first entry
+    synthesizeKey("KEY_ArrowUp"); // deselects
+    synthesizeKey("KEY_ArrowUp"); // footer
+    synthesizeKey("KEY_ArrowUp"); // last entry
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("fill username without autofill right", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    // Set first entry w/o triggering autocomplete
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_ArrowRight");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "", "password is empty");
+  });
+
+  add_named_task("fill username without autofill left", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    // Set first entry w/o triggering autocomplete
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_ArrowLeft");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "", "password is empty");
+  });
+
+  add_named_task("page up first", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    // Check first entry (page up)
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_ArrowDown"); // second
+    synthesizeKey("KEY_PageUp"); // first
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "pass-1", "password is set");
+  });
+
+  add_named_task("page down last", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    // Check last entry (page down)
+    synthesizeKey("KEY_ArrowDown"); // first
+    synthesizeKey("KEY_PageDown"); // footer
+    synthesizeKey("KEY_ArrowUp"); // last
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("untrusted event", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+  });
+
+  add_named_task("delete", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-3", "pass-3", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+
+    // XXX tried sending character "t" before/during dropdown to test
+    // filtering, but had no luck. Seemed like the character was getting lost.
+    // Setting uname.value didn't seem to work either. This works with a human
+    // driver, so I'm not sure what's up.
+
+    // Delete the first entry (of 3), "user-1"
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown");
+    const numLoginsBeforeDeletion = await LoginManager.countLogins(location.origin, "http://autocomplete:8888", null);
+    is(numLoginsBeforeDeletion, 3, "Correct number of logins before deleting one");
+
+    const countChangedPromise = notifyMenuChanged(4);
+    const deletionPromise = promiseStorageChanged(["removeLogin"]);
+    // On OS X, shift-backspace and shift-delete work, just delete does not.
+    // On Win/Linux, shift-backspace does not work, delete and shift-delete do.
+    synthesizeKey("KEY_Delete", {shiftKey: true});
+    await deletionPromise;
+
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const numLoginsAfterDeletion = await LoginManager.countLogins(location.origin, "http://autocomplete:8888", null);
+    is(numLoginsAfterDeletion, 2, "Correct number of logins after deleting one");
+    await countChangedPromise;
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-2", "username is set");
+    is(form.pword.value, "pass-2", "password is set");
+  });
+
+  add_named_task("delete second", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-3", "pass-3", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    // Delete the second entry (of 3), "user-2"
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Delete", {shiftKey: true});
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const numLoginsAfterDeletion = await LoginManager.countLogins(location.origin, "http://autocomplete:8888", null);
+    is(numLoginsAfterDeletion, 2, "Correct number of logins after deleting one");
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-3", "username is set");
+    is(form.pword.value, "pass-3", "password is set");
+  });
+
+  add_named_task("delete last", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-2", "pass-2", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "user-3", "pass-3", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    form.uname.focus();
+    await popupByArrowDown();
+
+    /* test 54 */
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    // Delete the last entry (of 3), "user-3"
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowDown");
+    const numLoginsBeforeDeletion = await LoginManager.countLogins(location.origin, "http://autocomplete:8888", null);
+    is(numLoginsBeforeDeletion, 3, "Correct number of logins before deleting one");
+    synthesizeKey("KEY_Delete", {shiftKey: true});
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const numLoginsAfterDeletion = await LoginManager.countLogins(location.origin, "http://autocomplete:8888", null);
+    is(numLoginsAfterDeletion, 2, "Correct number of logins after deleting one");
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user-1", "username is set");
+    is(form.pword.value, "pass-1", "password is set");
+  });
+
+
+  // Tests for single-user forms for ignoring autocomplete=off
+
+  add_named_task("default", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete2">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("password autocomplete off", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete2">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="off">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+
+    restoreForm(form);
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    // fields should not update just on selection
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("username autocomplete off", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete2">
+    <input type="text" name="uname" autocomplete="off">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+
+    restoreForm(form);
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    // value should not update just on selection
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("form autocomplete off", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete2" autocomplete="off">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+    restoreForm(form);
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    // value should not update just on selection
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("username and password autocomplete off", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete2">
+    <input type="text" name="uname" autocomplete="off">
+    <input type="password" name="pword" autocomplete="off">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+    restoreForm(form);
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    // value should not update just on selection
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("changing username does not touch password", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete2", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete2">
+    <input type="text" name="uname" autocomplete="off">
+    <input type="password" name="pword" autocomplete="off">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+
+    // Test that the password field remains filled in after changing
+    // the username.
+    form.uname.focus();
+    synthesizeKey("KEY_ArrowRight");
+    synthesizeKey("X", {shiftKey: true});
+    // Trigger the 'blur' event on uname
+    form.pword.focus();
+    is(form.uname.value, "userX", "username is set");
+    is(form.pword.value, "pass", "password is set");
+  });
+
+  add_named_task("additional username field in between", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete3", null, "user-1", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete3", null, "user-2", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete3">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+
+    // Insert a new username field into the form. We'll then make sure
+    // that invoking the autocomplete doesn't try to fill the form.
+    const newField = document.createElement("input");
+    newField.setAttribute("type", "text");
+    newField.setAttribute("name", "uname2");
+    form.insertBefore(newField, form.pword);
+    is(newField.value, "", "Verifying empty uname2");
+  });
+
+  add_named_task("additional username field in between and form reset", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete3", null, "user", "pass", "uname", "pword"]
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete3">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+
+    // Insert a new username field into the form. We'll then make sure
+    // that invoking the autocomplete doesn't try to fill the form.
+    const newField = document.createElement("input");
+    newField.setAttribute("type", "text");
+    newField.setAttribute("name", "uname2");
+    form.insertBefore(newField, form.pword);
+
+    restoreForm(form);
+    const autocompleteItems = await popupByArrowDown();
+    checkAutoCompleteResults(autocompleteItems,
+                             [
+                               "This connection is not secure. Logins entered here could be compromised. Learn More",
+                               "user"
+                             ],
+                             window.location.host,
+                             "Check dropdown is showing all logins while field is blank");
+
+
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    // The form changes, so we expect the old username field to get the
+    // selected autocomplete value, but neither the new username field nor
+    // the password field should have any values filled in.
+    await SimpleTest.promiseWaitForCondition(() => form.uname.value == "user",
+                                             "Wait for username to get filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "", "password is empty");
+    is(newField.value, "", "Verifying empty uname2");
+  });
+
+  add_named_task("two forms with different actions", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete", null, "user", "pass", "uname", "pword"]
+    );
+    const div = setContentForTask(`<div>
+      <form id="form1" action="http://autocomplete-other">
+        <input type="email" name="uname">
+        <input type="password" name="pword">
+      </form>
+      <form id="form2" action="http://autocomplete">
+        <input type="email" name="uname">
+        <input type="password" name="pword">
+      </form>
+    </div>`);
+    const form1 = div.querySelector("#form1");
+    const form2 = div.querySelector("#form2");
+    const autofillResult = await formAutofillResult(form1.id);
+    is(autofillResult, "no_saved_logins", "form has not been filled due to no saved logins");
+    const autofillResult2 = await formAutofillResult(form2.id);
+    is(autofillResult2, "filled", "form has been filled");
+
+    is(form2.uname.value, "user", "username is set");
+    is(form2.pword.value, "pass", "password is set");
+
+    restoreForm(form2);
+    is(form2.uname.value, "", "username is empty");
+    is(form2.pword.value, "", "password is empty");
+
+    form1.uname.focus();
+    is(form2.uname.value, "", "username is empty");
+    is(form2.pword.value, "", "password is empty");
+  });
+
+  add_named_task("filtering", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete", null, "form9userAB", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete", null, "form9userAAB", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+
+    const results = await popupBy(() => form.uname.focus());
+    checkAutoCompleteResults(results,
+                             [
+                               "This connection is not secure. Logins entered here could be compromised. Learn More",
+                               "form9userAAB",
+                               "form9userAB"
+                             ],
+                             window.location.host,
+                             "Check dropdown is showing all logins while field is blank");
+    synthesizeKey("KEY_Escape"); // Need to close the popup so we can get another popupshown after sending the string below.
+
+    const results2 = await popupBy(() => sendString("form9userAB"));
+    checkAutoCompleteResults(results2,
+                             [
+                               "This connection is not secure. Logins entered here could be compromised. Learn More",
+                               "form9userAB"
+                             ],
+                             window.location.host,
+                             "Check dropdown is showing login with only one 'A'");
+
+    is(form.uname.value, "form9userAB", "username is set");
+    is(form.pword.value, "", "password is empty");
+    form.uname.focus();
+    synthesizeKey("KEY_ArrowLeft");
+    const results3 = await popupBy(() => synthesizeKey("A", {shiftKey: true}));
+
+    is(form.uname.value, "form9userAAB", "username is set");
+    is(form.pword.value, "", "password is empty");
+    checkAutoCompleteResults(results3,
+                             [
+                               "This connection is not secure. Logins entered here could be compromised. Learn More",
+                               "form9userAAB"
+                             ],
+                             window.location.host, "Check dropdown is updated after inserting 'A'");
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "form9userAAB", "username is set");
+    is(form.pword.value, "pass-2", "password set");
+  });
+
+  add_named_task("autocomplete cache", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "form9userAB", "pass-1", "uname", "pword"],
+      [location.origin, "http://autocomplete:8888", null, "form9userAAB", "pass-2", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "multiple_logins", "form has not been filled due to multiple logins");
+
+    await popupBy(() => form.uname.focus());
+
+    await addLoginsInParent(
+      [location.origin, "https://autocomplete", null, "form9userAABzz", "pass-3", "uname", "pword"]
+    );
+
+    const promise1 = notifyMenuChanged(2);
+    sendString("z");
+    const results1 = await promise1;
+    checkAutoCompleteResults(results1, [
+                               "This connection is not secure. Logins entered here could be compromised. Learn More",
+    ], window.location.host,
+                             "Check popup does not have any login items");
+
+    // check that empty results are cached - bug 496466
+    const promise2 = notifyMenuChanged(2);
+    sendString("z");
+    const results2 = await promise2;
+    checkAutoCompleteResults(results2, [
+                               "This connection is not secure. Logins entered here could be compromised. Learn More",
+    ], window.location.host,
+                             "Check popup only has the footer when it opens");
+  });
+
+  add_named_task("formless", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user", "pass", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+
+    // Test form-less autocomplete
+    // TODO: wait - whats formless about this form?
+    restoreForm(form);
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("open on trusted focus", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user", "pass", "uname", "pword"]
+    );
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+
+    form.uname.value = "";
+    form.pword.value = "";
+
+    // Move focus to the password field so we can test the first click on the
+    // username field.
+    form.pword.focus();
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const firePrivEventPromise = new Promise((resolve) => {
+      form.uname.addEventListener("click", (e) => {
+        ok(e.isTrusted, "Ensure event is trusted");
+        resolve();
+      });
+    });
+    await popupBy(async () => {
+      synthesizeMouseAtCenter(form.uname, {});
+      await firePrivEventPromise;
+    });
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+  });
+
+  add_named_task("recipes", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "user", "pass", "uname", "pword"]
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete:8888">
+    <input type="text" name="uname">
+    <input type="text" name="pword">
+  </form>`);
+
+    await loadRecipes({
+      siteRecipes: [{
+        "hosts": [window.location.host],
+        "usernameSelector": "input[name='1']",
+        "passwordSelector": "input[name='2']",
+      }],
+    });
+
+    // Switch the password field to type=password so _fillForm marks the username
+    // field for autocomplete.
+    form.pword.type = "password";
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+    restoreForm(form);
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    synthesizeKey("KEY_ArrowDown");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+
+    // Now test recipes with blur on the username field.
+    restoreForm(form);
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    form.uname.value = "user";
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Tab");
+    const autofillResult3 = await formAutofillResult(form.id);
+    is(autofillResult3, "filled", "form has been filled");
+    is(form.uname.value, "user", "username is filled");
+    is(form.pword.value, "pass", "password is filled");
+    await resetRecipes();
+  });
+
+  add_named_task("form stays open upon empty search", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete:8888", null, "", "pass", "", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete:8888">
+    <input type="text" name="uname" value="prefilled">
+    <input type="password" name="pword" value="prefilled">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "existing_password", "form has not been filled due to existing password");
+
+    is(form.uname.value, "prefilled", "username is not changed");
+    is(form.pword.value, "prefilled", "password is not changed");
+
+    form.uname.scrollIntoView();
+    await popupBy(() => synthesizeMouseAtCenter(form.uname, {}));
+    form.uname.select();
+    synthesizeKey("KEY_Delete");
+
+    const popupState = await getPopupState();
+    is(popupState.open, true, "Check popup is still open");
+    is(form.uname.value, "", "username is emoty");
+    is(form.pword.value, "prefilled", "password is not changed");
+
+    info("testing password field");
+    synthesizeMouseAtCenter(form.pword, {});
+    form.pword.select();
+    const popupState2 = await getPopupState();
+    is(popupState2.open, false, "Check popup closed since password field isn't empty");
+    await popupBy(() => synthesizeKey("KEY_Delete"));
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+  });
+
+  add_named_task("username only", async () => {
+    await setStoredLoginsDuringTask(
+      [location.origin, "http://autocomplete", null, "user", "pass", "uname", "pword"],
+    );
+    const form = setContentForTask(`<form id="form1" action="http://autocomplete" autocomplete="off">
+    <input type="email" name="uname" value="prefilled" autocomplete="username">
+    <input type="password" name="pword">
+  </form>`);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "existing_username", "form has not been filled due to existing username");
+
+    is(form.uname.value, "prefilled", "username is not changed");
+    is(form.pword.value, "", "password is empty");
+    restoreForm(form);
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown"); // skip insecure warning
+    // Check first entry
+    synthesizeKey("KEY_ArrowDown");
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    synthesizeKey("KEY_Enter");
+    await untilAutocompletePopupClosed();
+    is(form.uname.value, "user", "username is set");
+    is(form.pword.value, "pass", "password is set");
+  });
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_related_realms.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_related_realms.html
new file mode 100644
index 0000000000..1dcd8b116e
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_basic_form_related_realms.html
@@ -0,0 +1,112 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test login autocomplete with related realms</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+Login Manager test: related realms autocomplete
+
+<template id="form1-template">
+  <form id="form1" action="https://autocomplete:8888/formtest.js">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>
+</template>
+
+<script class="testbody" type="text/javascript">
+  const formTemplate = document.getElementById("form1-template");
+
+  add_setup(async () => {
+    await setStoredLoginsDuringTest(
+      // Simple related domain relationship where example.com and other-example.com are in the related domains list
+      ["https://other-example.com", "https://other-example.com", null, "relatedUser1", "relatedPass1", "uname", "pword"],
+
+      // Example.com and example.co.uk are related, so sub.example.co.uk should appear on example.com's autocomplete dropdown
+      // The intent is to cover the ebay.com/ebay.co.uk and all other country TLD cases
+      // where the sign in page is actually signin.ebay.com/signin.ebay.co.uk but credentials could have manually been entered
+      // for ebay.com/ebay.co.uk or automatically stored as signin.ebay.com/sigin.ebay.co.uk
+      ["https://sub.example.co.uk", "https://sub.example.co.uk", null, "subUser1", "subPass1", "uname", "pword"],
+    );
+    listenForUnexpectedPopupShown();
+  });
+
+  add_named_task("form is initially empty", async () => {
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "no_saved_logins", "form has not been filled due to no saved logins");
+
+    // Make sure initial form is empty.
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+    const popupState = await getPopupState();
+    is(popupState.open, false, "Check popup is initially closed");
+  });
+
+  add_named_task("form related domain menuitems", async () => {
+    const form = setContentForTask(formTemplate);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "no_saved_logins", "form has not been filled due to no saved logins");
+
+    form.uname.focus();
+
+    const autocompleteItems = await popupByArrowDown();
+    const popupState = await getPopupState();
+
+    is(popupState.selectedIndex, -1, "Check no entires are selected upon opening");
+
+    const expectedMenuItems = ["relatedUser1", "subUser1"];
+    checkAutoCompleteResults(autocompleteItems, expectedMenuItems, window.location.host, "Check all menuitems are displayed correctly");
+
+    const acEvents = await getTelemetryEvents({ process: "parent", filterProps: TelemetryFilterPropsAC, clear: true });
+    is(acEvents.length, 1, "One autocomplete event");
+    checkACTelemetryEvent(acEvents[0], form.uname, {
+      "hadPrevious": "0",
+      "login": expectedMenuItems.length + "",
+      "loginsFooter": "1"
+    });
+    checkLoginForm(form.uname, "", form.pword, ""); // value shouldn't update just by opening
+
+    synthesizeKey("KEY_ArrowDown"); // first item
+    // value shouldn't update just by selecting
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+
+    synthesizeKey("KEY_Enter");
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    is(form.pword.value, "relatedPass1", "password should match the login that was selected");
+    checkLoginForm(form.uname, "relatedUser1", form.pword, "relatedPass1");
+    is(form.uname.value, "relatedUser1", "username is set");
+    is(form.pword.value, "relatedPass1", "password is set");
+
+    form.uname.value = "";
+    form.pword.value = "";
+    form.uname.focus();
+
+    await popupByArrowDown();
+
+    synthesizeKey("KEY_ArrowDown"); // first item
+    synthesizeKey("KEY_ArrowDown"); // second item
+    // value shouldn't update just by selecting
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+
+    synthesizeKey("KEY_Enter");
+    const autofillResult3 = await formAutofillResult(form.id);
+    is(autofillResult3, "filled", "form has been filled");
+    is(form.uname.value, "subUser1", "username is set");
+    is(form.pword.value, "subPass1", "password is set");
+  });
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_hasBeenTypePassword.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_hasBeenTypePassword.html
new file mode 100644
index 0000000000..0eb2beadc7
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_hasBeenTypePassword.html
@@ -0,0 +1,93 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test that passwords are autocompleted into fields that were previously type=password</title>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+Login Manager test: Test that passwords are autocompleted into fields that were
+previously type=password
+
+Usually the autocomplete login form only operates on password fields which are
+of type `password`. But when a password fields type has been changed to `text`
+via JavaScript, the password manager should still fill this form, because this
+is often used in real world forms to handle masking/unmasking of password
+fields.
+
+<template id="form1-template">
+  <form id="form1" action="https://www.example.com/formtest.js">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>
+</template>
+
+<script class="testbody" type="text/javascript">
+  const formTemplate = document.getElementById("form1-template");
+
+  add_setup(async () => {
+    const origin = window.location.origin;
+    await setStoredLoginsDuringTest(
+      [origin, origin, null, "user1", "pass1"],
+      [origin, origin, null, "user2", "pass2"]
+    );
+    listenForUnexpectedPopupShown();
+  });
+
+  add_named_task("autofill operates on a password field made text", async () => {
+    const form = setContentForTask(formTemplate);
+
+    // initial consume autofill event
+    await formAutofillResult(form.id);
+
+    info("Setting the password field type to text");
+    // This is similar to a site implementing their own password visibility/unmasking toggle
+    form.pword.type = "text";
+
+    // Trigger autocomplete popup
+    form.uname.focus();
+    const autocompleteItems =  await popupByArrowDown();
+
+    const popupState = await getPopupState();
+    is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
+
+    checkAutoCompleteResults(autocompleteItems, ["user1", "user2"], window.location.host,
+      "Check all menuitems are displayed correctly.");
+
+    synthesizeKey("KEY_ArrowDown"); // first item
+    // value shouldn't update just by selecting
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+
+    synthesizeKey("KEY_Enter");
+
+    const autofillResult1 = await formAutofillResult(form.id);
+    is(autofillResult1, "filled", "form has been filled");
+
+    is(form.uname.value, "user1", "username should match the login");
+    is(form.pword.value, "pass1", "password should match the login");
+
+    form.reset();
+
+    form.pword.focus();
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown"); // first item
+    // value shouldn't update just by selecting
+    is(form.uname.value, "", "username is empty");
+    is(form.pword.value, "", "password is empty");
+
+    synthesizeKey("KEY_Enter");
+    is(form.uname.value, "", "username should stay empty");
+    is(form.pword.value, "pass1", "Password should match the login that was selected");
+  });
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight.html
new file mode 100644
index 0000000000..49cedde0bc
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight.html
@@ -0,0 +1,86 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test form field autofill highlight</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+<script>
+const { ContentTaskUtils } = SpecialPowers.ChromeUtils.importESModule(
+  "resource://testing-common/ContentTaskUtils.sys.mjs"
+);
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [location.origin, "https://autocomplete", null, "user1", "pass1", "", ""],
+    [location.origin, "https://autocomplete", null, "user2", "pass2", "", ""]
+  );
+});
+
+add_task(async function test_field_highlight_on_autocomplete() {
+  const form = createLoginForm({
+    action: "https://autocomplete"
+  });
+
+  await openPopupOn(form.uname);
+  synthesizeKey("KEY_ArrowDown");
+  await synthesizeKey("KEY_Enter");
+
+  await ContentTaskUtils.waitForCondition(() => {
+    return form.uname.matches(":autofill")
+  }, "Highlight was successfully applied to the username field on username autocomplete");
+
+  ok(form.pword.matches(":autofill"),
+     "Highlight was successfully applied to the password field on username autocomplete");
+
+  // Clear existing highlight on login fields. We check by pressing the tab key after backspace
+  // (by shifting focus to the next element) because the tab key was known to cause a bug where the
+  // highlight is applied once again. See Bug 1526522.
+  form.uname.focus();
+  synthesizeKey("KEY_Backspace");
+  synthesizeKey("KEY_Tab");
+  ok(!form.uname.matches(":autofill"),
+     "Highlight was successfully removed on the username field");
+
+  synthesizeKey("KEY_Backspace");
+  synthesizeKey("KEY_Tab");
+  ok(!form.pword.matches(":autofill"),
+     "Highlight was successfully removed on the password field");
+
+  // Clear login fields.
+  form.uname.value = "";
+  form.pword.value = "";
+
+  // Test password field autocomplete.
+  await openPopupOn(form.pword);
+  synthesizeKey("KEY_ArrowDown");
+  synthesizeKey("KEY_Enter");
+
+  await ContentTaskUtils.waitForCondition(() => {
+    return form.pword.matches(":autofill");
+  }, "Highlight was successfully applied to the password field on password autocomplete");
+
+  // Clear existing highlight on the password field. We check by pressing the tab key after backspace
+  // (by shifting focus to the next element) because the tab key was known to cause a bug where the
+  // highlight is applied once again. See Bug 1526522.
+  synthesizeKey("KEY_Backspace");
+  synthesizeKey("KEY_Tab");
+
+  ok(!form.pword.matches(":autofill"),
+     "Highlight was successfully removed on the password field");
+
+  // Clear login fields.
+  form.uname.value = "";
+  form.pword.value = "";
+});
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_non_login.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_non_login.html
new file mode 100644
index 0000000000..eb82e90656
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_non_login.html
@@ -0,0 +1,91 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test form field autofill highlight</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+<script>
+function closeCurrentTab() {
+  runInParent(function cleanUpWindow() {
+    let window = Services.wm.getMostRecentWindow("navigator:browser");
+    window.gBrowser.removeTab(window.gBrowser.selectedTab);
+  });
+}
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [location.origin, "http://autocomplete", null, "user1", "pass1", "", ""],
+    [location.origin, "http://autocomplete", null, "user2", "pass2", "", ""]
+  );
+});
+
+add_task(async function test_field_highlight_on_pw_field_autocomplete_insecureWarning() {
+  const form = createLoginForm({
+    action: "http://autocomplete"
+  });
+  await promiseFormsProcessedInSameProcess();
+
+  // Press enter on insecure warning and check.
+  form.pword.focus();
+  await popupByArrowDown();
+  synthesizeKey("KEY_ArrowDown"); // insecure warning
+  synthesizeKey("KEY_Enter");
+
+  is(document.defaultView.getComputedStyle(form.pword).getPropertyValue("filter"), "none",
+     "Highlight is not applied to the password field if enter key is pressed on the insecure warning item");
+  is(document.defaultView.getComputedStyle(form.uname).getPropertyValue("filter"), "none",
+     "Highlight is not applied to the username field if enter key is pressed on the insecure warning item");
+
+  // Press tab on insecure warning and check.
+  await openPopupOn(form.pword);
+  synthesizeKey("KEY_ArrowDown"); // insecure warning
+  synthesizeKey("KEY_Tab");
+
+  is(document.defaultView.getComputedStyle(form.pword).getPropertyValue("filter"), "none",
+     "Highlight is not applied to the password field if tab key is pressed on the insecure warning item");
+  is(document.defaultView.getComputedStyle(form.uname).getPropertyValue("filter"), "none",
+     "Highlight is not applied to the username field if tab key is pressed on the insecure warning item");
+});
+
+add_task(async function test_field_highlight_on_pw_field_autocomplete_footer() {
+  const form = createLoginForm({
+    action: "http://autocomplete"
+  });
+  await promiseFormsProcessedInSameProcess();
+
+  // Press enter on the footer and check.
+  await openPopupOn(form.pword);
+  synthesizeKey("KEY_ArrowUp"); // footer
+  synthesizeKey("KEY_Enter");
+
+  is(document.defaultView.getComputedStyle(form.pword).getPropertyValue("filter"), "none",
+     "Highlight is not applied to the password field if enter key is pressed on the footer item");
+  is(document.defaultView.getComputedStyle(form.uname).getPropertyValue("filter"), "none",
+     "Highlight is not applied to the username field if enter key is pressed on the footer item");
+
+  closeCurrentTab();
+
+  // Press tab on the footer and check.
+  await openPopupOn(form.pword);
+  synthesizeKey("KEY_ArrowUp"); // footer
+  synthesizeKey("KEY_Tab");
+
+  is(document.defaultView.getComputedStyle(form.pword).getPropertyValue("filter"), "none",
+     "Highlight is not applied to the password field if tab key is pressed on the footer item");
+  is(document.defaultView.getComputedStyle(form.uname).getPropertyValue("filter"), "none",
+     "Highlight is not applied to the username field if tab key is pressed on the insecure warning item");
+
+  closeCurrentTab();
+});
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_username_only_form.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_username_only_form.html
new file mode 100644
index 0000000000..2451f47308
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_highlight_username_only_form.html
@@ -0,0 +1,56 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test form field autofill highlight</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+<script>
+const { ContentTaskUtils } = SpecialPowers.ChromeUtils.importESModule(
+  "resource://testing-common/ContentTaskUtils.sys.mjs"
+);
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [location.origin, "https://autocomplete", null, "user1", "pass1", "", ""],
+    [location.origin, "https://autocomplete", null, "user2", "pass2", "", ""]
+  );
+});
+
+add_task(async function test_username_field_in_username_only_form_highlight_on_autocomplete() {
+  const form = createLoginForm({
+    action: "https://autocomplete",
+    username: {
+      autocomplete: "username"
+    },
+    password: false
+  });
+
+  await openPopupOn(form.uname);
+  synthesizeKey("KEY_ArrowDown");
+  await synthesizeKey("KEY_Enter");
+
+  await ContentTaskUtils.waitForCondition(() => {
+    return form.uname.matches(":autofill");
+  }, "Highlight was successfully applied to the username field on username autocomplete");
+
+  // Clear existing highlight on login fields. We check by pressing the tab key after backspace
+  // (by shifting focus to the next element) because the tab key was known to cause a bug where the
+  // highlight is applied once again. See Bug 1526522.
+  form.uname.focus();
+  synthesizeKey("KEY_Backspace");
+  synthesizeKey("KEY_Tab");
+  ok(!form.uname.matches(":autofill"),
+     "Highlight was successfully removed on the username field");
+});
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_downgrade.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_downgrade.html
new file mode 100644
index 0000000000..44d830afe5
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_downgrade.html
@@ -0,0 +1,105 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autocomplete on an HTTPS page using upgraded HTTP logins</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content">
+  <iframe></iframe>
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+const origin = "http://" + window.location.host;
+const secureOrigin = "https://" + window.location.host;
+const iframe = document.getElementsByTagName("iframe")[0];
+let iframeDoc, hostname;
+let uname;
+let pword;
+
+// Restore the form to the default state.
+function restoreForm() {
+  return SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    this.content.document.getElementById("form-basic-password").focus();
+    this.content.document.getElementById("form-basic-username").value = "";
+    this.content.document.getElementById("form-basic-password").value = "";
+    this.content.document.getElementById("form-basic-username").focus();
+  });
+}
+
+const HTTP_FORM_URL = origin + "/tests/toolkit/components/passwordmgr/test/mochitest/form_basic.html";
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    // We have two actual HTTPS to avoid autofill before the schemeUpgrades pref flips to true.
+    [secureOrigin, secureOrigin, null, "name", "pass", "uname", "pword"],
+    [secureOrigin, secureOrigin, null, "name1", "pass1", "uname", "pword"],
+    // Same as above but HTTP instead of HTTPS (to test de-duping)
+    [origin, origin, null, "name1", "pass1", "uname", "pword"],
+    // Different HTTP login to upgrade with secure formActionOrigin
+    [origin, secureOrigin, null, "name2", "passHTTPtoHTTPS", "uname", "pword"]
+  );
+});
+
+async function setup(formUrl) {
+  await SpecialPowers.pushPrefEnv({"set": [["signon.schemeUpgrades", true]]});
+
+  let processedPromise = promiseFormsProcessed();
+  iframe.src = formUrl;
+  await new Promise(resolve => {
+    iframe.addEventListener("load", function() {
+      resolve();
+    }, {once: true});
+  });
+
+  await processedPromise;
+
+  hostname = await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    return this.content.document.documentURIObject.host;
+  });
+}
+
+add_task(async function test_autocomplete_https_downgrade() {
+  info("test_autocomplete_http, setup with " + HTTP_FORM_URL);
+  await setup(HTTP_FORM_URL);
+
+  let logins = await LoginManager.getAllLogins();
+  info("got logins: " + logins.map(l => l.origin));
+
+  // from a HTTP page, look for matching logins, we should never offer a login with an HTTPS scheme
+  // we're expecting just login2 as a match
+  let isCrossOrigin = false;
+  try {
+    // If this is a cross-origin test, the parent will be inaccessible. The fields
+    // should not be filled in.
+    window.parent.windowGlobalChild;
+  } catch(ex) {
+    isCrossOrigin = true;
+  }
+
+  await checkLoginFormInFrame(iframe, "form-basic-username", isCrossOrigin ? "" : "name1",
+                                      "form-basic-password", isCrossOrigin ? "" : "pass1");
+
+  // Trigger autocomplete popup
+  await restoreForm();
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is initially closed");
+  const autocompleteItems = await popupByArrowDown();
+  info("got results: " + autocompleteItems.join(", "));
+  popupState = await getPopupState();
+  is(popupState.selectedIndex, -1, "Check no entries are selected");
+  checkAutoCompleteResults(autocompleteItems, ["This connection is not secure. Logins entered here could be compromised. Learn More", "name1", "name2"], hostname, "initial");
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_upgrade.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_upgrade.html
new file mode 100644
index 0000000000..a0a81a8c88
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_https_upgrade.html
@@ -0,0 +1,191 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autocomplete on an HTTPS page using upgraded HTTP logins</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content">
+  <iframe></iframe>
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+const originSecure = "https://" + window.location.host;
+const originNonSecure = "http://" + window.location.host;
+const iframe = document.getElementsByTagName("iframe")[0];
+let iframeDoc, hostname;
+
+// Restore the form to the default state.
+function restoreForm() {
+  return SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    this.content.document.getElementById("form-basic-password").focus();
+    this.content.document.getElementById("form-basic-username").value = "";
+    this.content.document.getElementById("form-basic-password").value = "";
+    this.content.document.getElementById("form-basic-username").focus();
+  });
+}
+
+const HTTPS_FORM_URL = originSecure + "/tests/toolkit/components/passwordmgr/test/mochitest/form_basic.html";
+
+async function setup(formUrl = HTTPS_FORM_URL) {
+  await SpecialPowers.pushPrefEnv({"set": [["signon.schemeUpgrades", true]]});
+
+  let processedPromise = promiseFormsProcessed();
+  iframe.src = formUrl;
+  await new Promise(resolve => {
+    iframe.addEventListener("load", function() {
+      resolve();
+    }, {once: true});
+  });
+
+  await processedPromise;
+
+  hostname = await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    return this.content.document.documentURIObject.host;
+  });
+}
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    // We have two actual HTTPS to avoid autofill before the schemeUpgrades pref flips to true.
+    [originSecure, originSecure, null, "name", "pass", "uname", "pword"],
+    [originSecure, originSecure, null, "name1", "pass1", "uname", "pword"],
+
+    // Same as above but HTTP instead of HTTPS (to test de-duping)
+    [originNonSecure, originNonSecure, null, "name1", "pass1", "uname", "pword"],
+
+    // Different HTTP login to upgrade with secure formActionOrigin
+    [originNonSecure, originSecure, null, "name2", "passHTTPtoHTTPS", "uname", "pword"]
+  );
+});
+
+add_task(async function setup_https_frame() {
+  await setup(HTTPS_FORM_URL);
+});
+
+add_task(async function test_empty_first_entry() {
+  // Make sure initial form is empty.
+  await checkLoginFormInFrame(getIframeBrowsingContext(window, 0), "form-basic-username", "", "form-basic-password", "");
+  // Trigger autocomplete popup
+  await restoreForm();
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is initially closed");
+  let autocompleteItems = await popupBy();
+  popupState = await getPopupState();
+  is(popupState.selectedIndex, -1, "Check no entries are selected");
+  checkAutoCompleteResults(autocompleteItems, ["name", "name1", "name2"], hostname, "initial");
+
+  // Check first entry
+  let index0Promise = notifySelectedIndex(0);
+  synthesizeKey("KEY_ArrowDown");
+  await index0Promise;
+  await checkLoginFormInFrame(getIframeBrowsingContext(window, 0), "form-basic-username", "", "form-basic-password", ""); // value shouldn't update
+  synthesizeKey("KEY_Enter");
+  await promiseFormsProcessedInSameProcess();
+  await checkLoginFormInFrame(getIframeBrowsingContext(window, 0), "form-basic-username", "name", "form-basic-password", "pass");
+});
+
+add_task(async function test_empty_second_entry() {
+  await restoreForm();
+  await popupBy();
+  synthesizeKey("KEY_ArrowDown"); // first
+  synthesizeKey("KEY_ArrowDown"); // second
+  synthesizeKey("KEY_Enter");
+  await promiseFormsProcessedInSameProcess();
+  await checkLoginFormInFrame(getIframeBrowsingContext(window, 0), "form-basic-username", "name1", "form-basic-password", "pass1");
+});
+
+add_task(async function test_search() {
+  await restoreForm();
+  let results = await popupBy(async () => {
+    // We need to blur for the autocomplete controller to notice the forced value below.
+    await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+      let uname = this.content.document.getElementById("form-basic-username");
+      uname.blur();
+      uname.value = "name";
+      uname.focus();
+    });
+
+    sendChar("1");
+    synthesizeKey("KEY_ArrowDown"); // open
+  });
+  checkAutoCompleteResults(results, ["name1"], hostname, "check result deduping for 'name1'");
+  synthesizeKey("KEY_ArrowDown"); // first
+  synthesizeKey("KEY_Enter");
+  await promiseFormsProcessedInSameProcess();
+  await checkLoginFormInFrame(getIframeBrowsingContext(window, 0), "form-basic-username", "name1", "form-basic-password", "pass1");
+
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is now closed");
+});
+
+add_task(async function test_delete_first_entry() {
+  await restoreForm();
+  await popupBy();
+
+  let index0Promise = notifySelectedIndex(0);
+  synthesizeKey("KEY_ArrowDown");
+  await index0Promise;
+
+  let deletionPromise = promiseStorageChanged(["removeLogin"]);
+  // On OS X, shift-backspace and shift-delete work, just delete does not.
+  // On Win/Linux, shift-backspace does not work, delete and shift-delete do.
+  synthesizeKey("KEY_Delete", {shiftKey: true});
+  await deletionPromise;
+  await checkLoginFormInFrame(getIframeBrowsingContext(window, 0), "form-basic-username", "", "form-basic-password", "");
+
+  let results = await notifyMenuChanged(3, "name1");
+
+  checkAutoCompleteResults(results, ["name1", "name2"], hostname, "two logins should remain after deleting the first");
+  let popupState = await getPopupState();
+  is(popupState.open, true, "Check popup stays open after deleting");
+  synthesizeKey("KEY_Escape");
+  popupState = await getPopupState();
+  is(popupState.open, false, "Check popup closed upon ESC");
+});
+
+add_task(async function test_delete_duplicate_entry() {
+  await restoreForm();
+  await popupBy();
+
+  let index0Promise = notifySelectedIndex(0);
+  synthesizeKey("KEY_ArrowDown");
+  await index0Promise;
+
+  let deletionPromise = promiseStorageChanged(["removeLogin"]);
+  // On OS X, shift-backspace and shift-delete work, just delete does not.
+  // On Win/Linux, shift-backspace does not work, delete and shift-delete do.
+  synthesizeKey("KEY_Delete", {shiftKey: true});
+  await deletionPromise;
+  await checkLoginFormInFrame(getIframeBrowsingContext(window, 0), "form-basic-username", "", "form-basic-password", "");
+
+  is(await LoginManager.countLogins(originNonSecure, originNonSecure, null), 1,
+     "Check that the HTTP login remains");
+  is(await LoginManager.countLogins(originSecure, originSecure, null), 0,
+     "Check that the HTTPS login was deleted");
+
+  // Two menu items should remain as the HTTPS login should have been deleted but
+  // the HTTP would remain.
+  let results = await notifyMenuChanged(2, "name2");
+
+  checkAutoCompleteResults(results, ["name2"], hostname, "one login should remain after deleting the HTTPS name1");
+  let popupState = await getPopupState();
+  is(popupState.open, true, "Check popup stays open after deleting");
+  synthesizeKey("KEY_Escape");
+  popupState = await getPopupState();
+  is(popupState.open, false, "Check popup closed upon ESC");
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation.html
new file mode 100644
index 0000000000..3fd8b1e90b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation.html
@@ -0,0 +1,596 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofill and autocomplete on autocomplete=new-password fields</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <script src="../../../satchel/test/satchel_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+Login Manager test: autofill with password generation on `autocomplete=new-password` fields.
+
+<template id="form1-template">
+  <form id="form1" action="https://autofill">
+    <input type="text" name="uname">
+    <input type="password" name="p">
+    <button type="submit" name="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form2-template">
+  <form id="form2" action="https://autofill">
+    <input type="text" name="uname">
+    <input type="password" name="password" autocomplete="new-password">
+    <button type="submit" name="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form3-template">
+  <form id="form3" action="https://autofill">
+    <input type="text" name="username">
+    <label>New password<input type="password" name="password"></label>
+    <button type="submit" name="submit">Submit</button>
+  </form>
+</template>
+
+<script class="testbody" type="text/javascript">
+  const { TestUtils } = SpecialPowers.ChromeUtils.importESModule(
+    "resource://testing-common/TestUtils.sys.mjs"
+  );
+
+  const formTemplates = {
+    form1: document.getElementById("form1-template"),
+    form2: document.getElementById("form2-template"),
+    form3: document.getElementById("form3-template"),
+  };
+
+  const dateAndTimeFormatter = new SpecialPowers.Services.intl.DateTimeFormat(undefined, {
+    dateStyle: "medium",
+  });
+
+  async function showACPopup(formNumber, expectedACLabels) {
+    const autocompleteItems = await popupByArrowDown();
+    checkAutoCompleteResults(autocompleteItems, expectedACLabels,
+                             window.location.host, "Check all rows are correct");
+  }
+
+  function clearGeneratedPasswords() {
+    const { LoginManagerParent } = ChromeUtils.importESModule(
+      "resource://gre/modules/LoginManagerParent.sys.mjs"
+    );
+    if (LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin()) {
+      LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+    }
+  }
+
+  add_named_task("autofill autocomplete username no generation", async () => {
+    await setPreferencesForTask(
+      ["signon.generation.available", false],
+      ["signon.generation.enabled", false],
+    );
+    await setStoredLoginsDuringTask([location.origin, "https://autofill", null, "user1", "pass1"]);
+
+    const form1 = setContentForTask(formTemplates.form1);
+
+    const autofillResult1 = await formAutofillResult(form1.id);
+    is(autofillResult1, "filled", "form has not been filled due to multiple logins");
+
+    // reference form was filled as expected?
+    is(form1.uname.value, "user1", "username is filled");
+    is(form1.p.value, "pass1", "password is filled");
+
+    const form2 = setContentForTask(formTemplates.form2);
+    const autofillResult2 = await formAutofillResult(form2.id);
+    is(autofillResult2, "password_autocomplete_new_password", "form has not been filled due to password_autocomplete_new_password");
+
+    // 2nd form should not be filled
+    is(form2.uname.value, "", "username is empty");
+    is(form2.password.value, "", "password is empty");
+
+    form2.uname.focus();
+    await showACPopup(2, ["user1"]);
+
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+
+    const autofillResult3 = await formAutofillResult(form2.id);
+    is(autofillResult3, "filled", "form has been filled");
+    is(form2.uname.value, "user1", "username is filled");
+    is(form2.password.value, "pass1", "password is filled");
+  });
+
+  add_named_task("autofill autocomplete password no generation", async () => {
+    await setPreferencesForTask(
+      ["signon.generation.available", false],
+      ["signon.generation.enabled", false],
+    );
+    await setStoredLoginsDuringTask([location.origin, "https://autofill", null, "user1", "pass1"]);
+
+    const form = setContentForTask(formTemplates.form2);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "password_autocomplete_new_password", "form has not been filled due to password_autocomplete_new_password");
+
+    // form should not be filled
+    is(form.uname.value, "", "username is empty");
+    is(form.password.value, "", "password is empty");
+
+    form.password.focus();
+    // No generation option on username fields.
+    await showACPopup(2, ["user1"]);
+
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+
+    await SimpleTest.promiseWaitForCondition(() => form.password.value == "pass1", "Check pw filled");
+    is(form.uname.value, "", "username is empty");
+    is(form.password.value, "pass1", "password is filled");
+
+    // No autocomplete results should appear for non-empty pw fields.
+    await noPopupByArrowDown();
+  });
+
+  add_named_task("autofill autocomplete username no generation #2", async () => {
+    await setPreferencesForTask(
+      ["signon.generation.available", false],
+      ["signon.generation.enabled", false],
+    );
+    await setStoredLoginsDuringTask([location.origin, "https://autofill", null, "user1", "pass1"]);
+
+    const form = setContentForTask(formTemplates.form2);
+    const autofillResult1 = await formAutofillResult(form.id);
+    is(autofillResult1, "password_autocomplete_new_password", "form has not been filled due to password_autocomplete_new_password");
+
+    // form should not be filled
+    is(form.uname.value, "", "username is empty");
+    is(form.password.value, "", "password is empty");
+
+    form.uname.focus();
+    // No generation option on username fields.
+    await showACPopup(2, ["user1"]);
+
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+
+    const autofillResult2 = await formAutofillResult(form.id);
+    is(autofillResult2, "filled", "form has been filled");
+    is(form.uname.value, "user1", "username is filled");
+    is(form.password.value, "pass1", "password is filled");
+  });
+
+  add_named_task("autofill autocomplete passsword with generation", async () => {
+    await setPreferencesForTask(
+      ["signon.generation.available", true],
+      ["signon.generation.enabled", true],
+    );
+
+    runInParent(clearGeneratedPasswords);
+    await setStoredLoginsDuringTask([location.origin, "https://autofill", null, "user1", "pass1"]);
+
+    const form = setContentForTask(formTemplates.form2);
+    const formNumber = 2;
+
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "password_autocomplete_new_password", "form has not been filled due to password_autocomplete_new_password");
+
+    form.reset();
+
+    // form should not be filled
+    is(form.uname.value, "", "username is empty");
+    is(form.password.value, "", "password is empty");
+
+    form.password.focus();
+
+    await showACPopup(formNumber, [
+      "user1",
+      "Use a Securely Generated Password",
+    ]);
+
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    await SimpleTest.promiseWaitForCondition(() => form.password.value == "pass1", "Check pw filled");
+    is(form.uname.value, "", "username is empty");
+    is(form.password.value, "pass1", "password is filled");
+
+    // No autocomplete results should appear for non-empty pw fields.
+    await noPopupByArrowDown();
+
+    info("Removing all logins to test auto-saving of generated passwords");
+    await LoginManager.removeAllUserFacingLogins();
+
+    while (form.password.value) {
+      synthesizeKey("KEY_Backspace");
+    }
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blanked field");
+
+    info("This time select the generated password");
+    await showACPopup(formNumber, [
+      "Use a Securely Generated Password",
+    ]);
+
+    synthesizeKey("KEY_ArrowDown");
+    const storageAddPromise = promiseStorageChanged(["addLogin"]);
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Before first fill of generated pw");
+    synthesizeKey("KEY_Enter");
+
+    info("waiting for the password field to be filled with the generated password");
+    await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check generated pw filled");
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, "After first fill of generated pw");
+    info("Wait for generated password to be added to storage");
+    await storageAddPromise;
+
+    let logins = await LoginManager.getAllLogins();
+    const timePasswordChanged = logins[logins.length - 1].timePasswordChanged;
+    const time = dateAndTimeFormatter.format(new Date(timePasswordChanged));
+    const LABEL_NO_USERNAME = "No username (" + time + ")";
+
+    const generatedPW = form.password.value;
+    is(generatedPW.length, GENERATED_PASSWORD_LENGTH, "Check generated password length");
+    ok(generatedPW.match(GENERATED_PASSWORD_REGEX), "Check generated password format");
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, "After fill");
+
+    info("Check field is masked upon blurring");
+    synthesizeKey("KEY_Tab"); // blur
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "After blur");
+    synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, "After shift-tab to focus again");
+    // Remove selection for OS where the whole value is selected upon focus.
+    synthesizeKey("KEY_ArrowRight");
+
+    while (form.password.value) {
+      LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, form.password.value);
+      synthesizeKey("KEY_Backspace");
+    }
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blanked field");
+
+    info("Blur the empty field to trigger a 'change' event");
+    synthesizeKey("KEY_Tab"); // blur
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blur after blanking");
+    synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Focus again after blanking");
+
+    info("Type a single character after blanking");
+    synthesizeKey("@");
+
+    info("Blur the single-character field to trigger a 'change' event");
+    synthesizeKey("KEY_Tab"); // blur
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blur after backspacing");
+    synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Focus again after backspacing");
+    synthesizeKey("KEY_Backspace"); // Blank the field again
+
+    await showACPopup(formNumber, [
+      LABEL_NO_USERNAME,
+      "Use a Securely Generated Password",
+    ]);
+
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check generated pw filled");
+    // Same generated password should be used, even despite the 'change' to @ earlier.
+    is(form.uname.value, "", "username is empty");
+    is(form.password.value, generatedPW, "password is filled with generated password");
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, "Second fill of the generated pw");
+
+    logins = await LoginManager.getAllLogins();
+    is(logins.length, 1, "Still 1 login after filling the generated password a 2nd time");
+    is(logins[0].timePasswordChanged, timePasswordChanged, "Saved login wasn't changed");
+    is(logins[0].password, generatedPW, "Password is the same");
+
+    info("filling the saved login to ensure the field is masked again");
+
+    while (form.password.value) {
+      LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, form.password.value);
+      synthesizeKey("KEY_Backspace");
+    }
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blanked field again");
+
+    info("Blur the field to trigger a 'change' event again");
+    synthesizeKey("KEY_Tab"); // blur
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blur after blanking again");
+    synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Focus again after blanking again");
+    // Remove selection for OS where the whole value is selected upon focus.
+    synthesizeKey("KEY_ArrowRight");
+
+    await showACPopup(formNumber, [
+      LABEL_NO_USERNAME,
+      "Use a Securely Generated Password",
+    ]);
+
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check saved generated pw filled");
+    // Same generated password should be used but from storage
+    is(form.uname.value, "", "username is empty");
+    is(form.password.value, generatedPW, "password is filled with generated password");
+    // Passwords from storage should always be masked.
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "after fill from storage");
+    synthesizeKey("KEY_Tab"); // blur
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "after blur");
+    synthesizeKey("KEY_Tab", { shiftKey: true }); // focus
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "after shift-tab to focus again");
+  });
+
+  add_named_task("autofill autocomplete passsword with generation #2", async () => {
+    await setPreferencesForTask(
+      ["signon.generation.available", true],
+      ["signon.generation.enabled", true],
+    );
+
+    runInParent(clearGeneratedPasswords);
+    await setStoredLoginsDuringTask([location.origin, "https://autofill", null, "user1", "pass1"]);
+
+    const form = setContentForTask(formTemplates.form3);
+    const formNumber = 3;
+
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "filled", "form has been filled");
+
+    form.reset();
+
+    is(form.username.value, "", "username is empty");
+    is(form.password.value, "", "password is empty");
+
+    form.password.focus();
+
+    await showACPopup(formNumber, [
+      "user1",
+      "Use a Securely Generated Password",
+    ]);
+
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    await SimpleTest.promiseWaitForCondition(() => form.password.value == "pass1", "Check pw filled");
+    is(form.username.value, "", "username is empty");
+    is(form.password.value, "pass1", "password is filled");
+
+    // No autocomplete results should appear for non-empty pw fields.
+    await noPopupByArrowDown();
+
+    info("Removing all logins to test auto-saving of generated passwords");
+    await LoginManager.removeAllUserFacingLogins();
+
+    while (form.password.value) {
+      synthesizeKey("KEY_Backspace");
+    }
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blanked field");
+
+    info("This time select the generated password");
+    await showACPopup(formNumber, [
+      "Use a Securely Generated Password",
+    ]);
+
+    synthesizeKey("KEY_ArrowDown");
+    const storageAddPromise = promiseStorageChanged(["addLogin"]);
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Before first fill of generated pw");
+    synthesizeKey("KEY_Enter");
+
+    info("waiting for the password field to be filled with the generated password");
+    await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check generated pw filled");
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, "After first fill of generated pw");
+    info("Wait for generated password to be added to storage");
+    await storageAddPromise;
+
+    let logins = await LoginManager.getAllLogins();
+    const timePasswordChanged = logins[logins.length - 1].timePasswordChanged;
+    const time = dateAndTimeFormatter.format(new Date(timePasswordChanged));
+    const LABEL_NO_USERNAME = "No username (" + time + ")";
+
+    const generatedPW = form.password.value;
+    is(generatedPW.length, GENERATED_PASSWORD_LENGTH, "Check generated password length");
+    ok(generatedPW.match(GENERATED_PASSWORD_REGEX), "Check generated password format");
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, "After fill");
+
+    info("Check field is masked upon blurring");
+    synthesizeKey("KEY_Tab"); // blur
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "After blur");
+    synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, "After shift-tab to focus again");
+    // Remove selection for OS where the whole value is selected upon focus.
+    synthesizeKey("KEY_ArrowRight");
+
+    while (form.password.value) {
+      LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, form.password.value);
+      synthesizeKey("KEY_Backspace");
+    }
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blanked field");
+
+    info("Blur the empty field to trigger a 'change' event");
+    synthesizeKey("KEY_Tab"); // blur
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blur after blanking");
+    synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Focus again after blanking");
+
+    info("Type a single character after blanking");
+    synthesizeKey("@");
+
+    info("Blur the single-character field to trigger a 'change' event");
+    synthesizeKey("KEY_Tab"); // blur
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blur after backspacing");
+    synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Focus again after backspacing");
+    synthesizeKey("KEY_Backspace"); // Blank the field again
+
+    await showACPopup(formNumber, [
+      LABEL_NO_USERNAME,
+      "Use a Securely Generated Password",
+    ]);
+
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check generated pw filled");
+    // Same generated password should be used, even despite the 'change' to @ earlier.
+    is(form.username.value, "", "username is empty");
+    is(form.password.value, generatedPW, "password is filled with generated password");
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, "Second fill of the generated pw");
+
+    logins = await LoginManager.getAllLogins();
+    is(logins.length, 1, "Still 1 login after filling the generated password a 2nd time");
+    is(logins[0].timePasswordChanged, timePasswordChanged, "Saved login wasn't changed");
+    is(logins[0].password, generatedPW, "Password is the same");
+
+    info("filling the saved login to ensure the field is masked again");
+
+    while (form.password.value) {
+      LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, false, form.password.value);
+      synthesizeKey("KEY_Backspace");
+    }
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blanked field again");
+
+    info("Blur the field to trigger a 'change' event again");
+    synthesizeKey("KEY_Tab"); // blur
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Blur after blanking again");
+    synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "Focus again after blanking again");
+    // Remove selection for OS where the whole value is selected upon focus.
+    synthesizeKey("KEY_ArrowRight");
+
+    await showACPopup(formNumber, [
+      LABEL_NO_USERNAME,
+      "Use a Securely Generated Password",
+    ]);
+
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check saved generated pw filled");
+    // Same generated password should be used but from storage
+    is(form.username.value, "", "username is empty");
+    is(form.password.value, generatedPW, "password is filled with generated password");
+    // Passwords from storage should always be masked.
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "after fill from storage");
+    synthesizeKey("KEY_Tab"); // blur
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "after blur");
+    synthesizeKey("KEY_Tab", { shiftKey: true }); // focus
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.password, true, "after shift-tab to focus again");
+  });
+
+  add_named_task("autofill autocomplete password save login disabled", async () => {
+    await setPreferencesForTask(
+      ["signon.generation.available", true],
+      ["signon.generation.enabled", true],
+    );
+    await setStoredLoginsDuringTask([location.origin, "https://autofill", null, "user1", "pass1"]);
+
+    const form = setContentForTask(formTemplates.form2);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "password_autocomplete_new_password", "form has not been filled due to password_autocomplete_new_password");
+
+    // form should not be filled
+    is(form.uname.value, "", "username is empty");
+    is(form.password.value, "", "password is empty");
+
+    const formOrigin = new URL(document.documentURI).origin;
+    is(formOrigin, location.origin, "Expected form origin");
+
+    await LoginManager.setLoginSavingEnabled(location.origin, false);
+
+    form.password.focus();
+    // when login-saving is disabled for an origin, we expect no generated password row here
+    await showACPopup(2, ["user1"]);
+
+    // close any open menu
+    synthesizeKey("KEY_Escape");
+    await untilAutocompletePopupClosed();
+
+    await LoginManager.setLoginSavingEnabled(location.origin, true);
+  });
+
+  add_named_task("delete and reselect generated password", async () => {
+    await setPreferencesForTask(
+      ["signon.generation.available", true],
+      ["signon.generation.enabled", true],
+    );
+    await setStoredLoginsDuringTask([location.origin, "https://autofill", null, "user1", "pass1"]);
+
+    const form = setContentForTask(formTemplates.form2);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "password_autocomplete_new_password", "form has not been filled due to password_autocomplete_new_password");
+
+    info("Removing all logins to test auto-saving of generated passwords");
+    await LoginManager.removeAllUserFacingLogins();
+
+    // form should not be filled
+    is(form.uname.value, "", "username is empty");
+    is(form.password.value, "", "password is empty");
+
+    async function showAndSelectACPopupItem(index) {
+      form.password.focus();
+      if (form.password.value) {
+        form.password.select();
+        synthesizeKey("KEY_Backspace");
+      }
+      const autocompleteItems = await popupByArrowDown();
+      if (index < 0) {
+        index = autocompleteItems.length + index;
+      }
+      for (let i = 0; i <= index; i++) {
+        synthesizeKey("KEY_ArrowDown");
+      }
+      await TestUtils.waitForTick();
+      return autocompleteItems[index];
+    }
+
+    let menuLabel, itemIndex, savedLogins;
+
+    // fill the password field with the generated password via auto-complete menu
+    const addLoginPromise = promiseStorageChanged(["addLogin"]);
+    // select last-but-2 item - the one before the footer
+    menuLabel = await showAndSelectACPopupItem(-2);
+    is(menuLabel, "Use a Securely Generated Password", "Check item label");
+    synthesizeKey("KEY_Enter");
+    info("waiting for the password field to be filled with the generated password");
+    await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check generated pw filled");
+    info("Wait for generated password to be added to storage");
+    await addLoginPromise;
+
+    savedLogins = await LoginManager.getAllLogins();
+    is(savedLogins.length, 1, "Check saved logins count");
+
+    form.uname.focus();
+    await TestUtils.waitForTick();
+
+    is(form.password.value.length, LoginTestUtils.generation.LENGTH, "Check password looks generated");
+    const GENERATED_PASSWORD = form.password.value;
+
+    info("clear the password field and delete the saved login using the AC menu")
+    const removeLoginPromise = promiseStorageChanged(["removeLogin"]);
+
+    itemIndex = 0;
+    menuLabel = await showAndSelectACPopupItem(itemIndex);
+    ok(menuLabel.includes("No username"), "Check first item is the auto-saved login");
+    // Send delete to remove the auto-saved login from storage
+    // On OS X, shift-backspace and shift-delete work, just delete does not.
+    // On Win/Linux, shift-backspace does not work, delete and shift-delete do.
+    synthesizeKey("KEY_Delete", {shiftKey: true});
+    await removeLoginPromise;
+
+    form.uname.focus();
+    await TestUtils.waitForTick();
+
+    savedLogins = await LoginManager.getAllLogins();
+    is(savedLogins.length, 0, "Check saved logins count");
+
+    info("Re-fill with the generated password");
+    // select last-but-2 item - the one before the footer
+    menuLabel = await showAndSelectACPopupItem(-2);
+    is(menuLabel, "Use a Securely Generated Password", "Check item label");
+    synthesizeKey("KEY_Enter");
+    info("waiting for the password field to be filled with the generated password");
+    await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check generated pw filled");
+
+    form.uname.focus();
+    await TestUtils.waitForTick();
+    is(form.password.value, GENERATED_PASSWORD, "Generated password has not changed");
+  });
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation_confirm.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation_confirm.html
new file mode 100644
index 0000000000..54cb450815
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation_confirm.html
@@ -0,0 +1,380 @@
+<!DOCTYPE HTML>
+<html>
+  <head>
+  <meta charset="utf-8">
+  <title>Test filling generated passwords into confirm password fields</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <script src="../../../satchel/test/satchel_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+Login Manager test: filling generated passwords into confirm password fields
+
+<template id="form1-template">
+  <form id="form1" action="https://example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="new-password">
+    <input type="password" name="pwordNext">
+    <button type="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form2-template">
+  <form id="form2" action="https://example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="new-password">
+    <input type="password" name="pwordNext" value="initial value">
+    <button type="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form3-template">
+  <form id="form3" action="https://example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="new-password">
+    <input type="password" name="pwordNext" readonly>
+    <button type="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form4-template">
+  <form id="form4" action="https://example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="new-password">
+    <input type="password" name="pwordNext" disabled>
+    <button type="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form5-template">
+  <form id="form5" action="https://example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="new-password">
+    <input type="password" name="pwordBetween">
+    <input type="password" name="pwordNext" autocomplete="new-password">
+    <button type="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form6-template">
+  <form id="form6" action="https://example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="new-password">
+    <input type="password" name="pwordNext">
+    <input type="password" name="pwordAfter" autocomplete="new-password" disabled>
+    <button type="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form7-template">
+  <form id="form7" action="https://example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="new-password">
+    <input type="password" name="junk0">
+    <input type="password" name="junk1">
+    <input type="password" name="junk2">
+    <input type="password" name="junk3">
+    <input type="password" name="junk4">
+    <input type="password" name="pwordNext" autocomplete="new-password">
+    <button type="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form8-template">
+  <form id="form8" action="https://example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="new-password">
+    <input type="password" name="junk0" disabled>
+    <input type="password" name="junk1" disabled>
+    <input type="password" name="junk2" disabled>
+    <input type="password" name="junk3" disabled>
+    <input type="password" name="junk4" disabled>
+    <input type="password" name="pwordNext" autocomplete="new-password">
+    <button type="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form9-template">
+  <form id="form9" action="https://example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="new-password">
+    <input type="hidden" name="junk0">
+    <input type="hidden" name="junk1">
+    <input type="hidden" name="junk2">
+    <input type="hidden" name="junk3">
+    <input type="hidden" name="junk4">
+    <input type="password" name="pwordNext" autocomplete="new-password">
+    <button type="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form10-template">
+  <form id="form10" action="https://example.com">
+    <input type="text" name="uname">
+    <input type="password" name="pword" autocomplete="new-password">
+    <input type="password" name="pwordNext" autocomplete="new-password">
+    <input type="password" name="pwordExtra" autocomplete="new-password">
+    <button type="submit">Submit</button>
+  </form>
+</template>
+
+<script class="testbody" type="text/javascript">
+  const formTemplates = {
+    form1: document.getElementById("form1-template"),
+    form2: document.getElementById("form2-template"),
+    form3: document.getElementById("form3-template"),
+    form4: document.getElementById("form4-template"),
+    form5: document.getElementById("form5-template"),
+    form6: document.getElementById("form6-template"),
+    form7: document.getElementById("form7-template"),
+    form8: document.getElementById("form8-template"),
+    form9: document.getElementById("form9-template"),
+    form10: document.getElementById("form10-template"),
+  };
+
+  const setupScript = runInParent(function parentTestSetup() {
+    const { LoginTestUtils } = ChromeUtils.importESModule(
+      "resource://testing-common/LoginTestUtils.sys.mjs"
+    );
+
+    addMessageListener(
+      "resetLoginsAndGeneratedPasswords", () => {
+        LoginTestUtils.clearData();
+        LoginTestUtils.resetGeneratedPasswordsCache();
+      }
+    );
+  });
+
+  function resetLoginsAndGeneratedPasswords() {
+    return setupScript.sendAsyncMessage("resetLoginsAndGeneratedPasswords");
+  }
+
+  async function triggerPasswordGeneration(form) {
+    await openPopupOn(form.pword);
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+    await SimpleTest.promiseWaitForCondition(() => !!form.pword.value, "Wait for generated password to get filled");
+  }
+
+  add_named_task("autocomplete menu contains option to generate password", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+
+    const { items } = await openPopupOn(form.pword);
+
+    checkAutoCompleteResults(items, [
+      "Use a Securely Generated Password"
+    ], location.host, "Check all rows are correct");
+  });
+
+  add_named_task("username field highlight", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+    ok(!form.uname.matches(":autofill"), "Highlight was not applied to the username field");
+  });
+
+  add_named_task("password field highlight", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+    ok(form.pword.matches(":autofill"), "Highlight was applied to the password field");
+  });
+
+  add_named_task("username field is left untouched", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+    is(form.uname.value, "", "Value is still empty")
+  });
+
+  add_named_task("generated password looks like a generated password", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+    const generatedPassword = form.pword.value;
+    is(generatedPassword.length, GENERATED_PASSWORD_LENGTH, "Generated password length matches");
+    ok(generatedPassword.match(GENERATED_PASSWORD_REGEX), "Generated password format matches");
+  });
+
+  add_named_task("password confirmation also gets filled with the generated password", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+    is(form.pwordNext.value, form.pword.value, "Value of the confirm field has been filled with generated password");
+  });
+
+  add_named_task("password field is not masked initially after password generation", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, false, "password field is not masked after password generation");
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.pwordNext, true, "password confirmation field is masked after user input");
+  });
+
+  add_named_task("password field is masked after user input", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+    form.pwordNext.focus();
+    form.pwordNext.select();
+    synthesizeKey("KEY_Backspace");
+    synthesizeKey("a");
+    form.pwordNext.blur();
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.pword, true, "password field is masked after user input");
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.pwordNext, true, "password confirmation field is also masked after user input");
+  });
+
+  add_named_task("password field highlight is cleared after user input", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+    form.pwordNext.focus();
+    form.pwordNext.select();
+    synthesizeKey("KEY_Backspace");
+    synthesizeKey("a");
+    form.pwordNext.blur();
+    await SimpleTest.promiseWaitForCondition(() => !form.pwordNext.matches(":autofill"), "Highlight was cleared");
+  });
+
+  add_named_task("generated password can be changed", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+    const generatedPassword = form.pword.value;
+    form.pword.focus();
+    synthesizeKey("KEY_End");
+    synthesizeKey("@");
+    is(form.pword.value, `${generatedPassword}@`, "Value of the password field changed");
+  });
+
+  add_named_task("password confirmation field does not receive changes from password field", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+    const generatedPassword = form.pword.value;
+
+    // changing the password field value should result in a message sent to the parent process
+    const messageSentPromise = getPasswordEditedMessage();
+
+    form.pword.focus();
+    synthesizeKey("KEY_End");
+    synthesizeKey("@");
+
+    // bluring results in a "change" event
+    form.pword.blur();
+    await messageSentPromise;
+
+    is(form.pwordNext.value, generatedPassword, "Value of the confirm field still holds the original generated password");
+    ok(form.pwordNext.matches(":autofill"), "Highlight is still applied to password confirmation field");
+  });
+
+  add_named_task("password confirmation field behaves like a normal password field once changed", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    await triggerPasswordGeneration(form);
+
+    form.pwordNext.focus();
+    form.pwordNext.select();
+    synthesizeKey("KEY_Backspace");
+
+    // verify the focused confirm field now masks its input like a normal,
+    // non-generated password field after being emptied
+    form.pwordNext.focus();
+    synthesizeKey("a");
+    form.pwordNext.blur();
+
+    LOGIN_FIELD_UTILS.checkPasswordMasked(form.pwordNext, true, "password confirmation field is masked");
+    await SimpleTest.promiseWaitForCondition(() => !form.pwordNext.matches(":autofill"), "highlight was cleared");
+  });
+
+  add_named_task("password confirmation also gets filled with the generated password, even if it has been changed to be of type text", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    form.pwordNext.type = "text";
+    await triggerPasswordGeneration(form);
+    is(form.pwordNext.value, form.pword.value, "Value of the confirm field has been filled with generated password");
+  });
+
+  add_named_task("password confirmation does not get filled with the generated password if it is not empty", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form2);
+    await triggerPasswordGeneration(form);
+    is(form.pwordNext.value, "initial value", "Value of the confirm field has been filled with generated password");
+  });
+
+  add_named_task("password confirmation does not get filled with the generated password if it has been edited", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form1);
+    form.pwordNext.focus()
+    sendString("edited value");
+    await triggerPasswordGeneration(form);
+    is(form.pwordNext.value, "edited value", "Value of the confirm field has been filled with generated password");
+  });
+
+  add_named_task("password confirmation does not get filled with the generated password if its readonly", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form3);
+    await triggerPasswordGeneration(form);
+    is(form.pwordNext.value, "", "Value of the confirm field has been filled with generated password");
+  });
+
+  add_named_task("password confirmation does not get filled with the generated password if its disabled", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form4);
+    await triggerPasswordGeneration(form);
+    is(form.pwordNext.value, "", "Value of the confirm field has been filled with generated password");
+  });
+
+  add_named_task("password confirmation matching autocomplete info gets filled with the generated password", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form5);
+    await triggerPasswordGeneration(form);
+    is(form.pwordBetween.value, "", "Value of the between field has not been filled");
+    is(form.pwordNext.value, form.pword.value, "Value of the confirm field has been filled with generated password");
+  });
+
+  add_named_task("password confirmation matching autocomplete info gets ignored if its disabled, even if has autocomplete info", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form6);
+    await triggerPasswordGeneration(form);
+    is(form.pwordNext.value, form.pword.value, "Value of the confirm field has been filled with generated password");
+    is(form.pwordAfter.value, "", "Value of the disabled confirmation field has not been filled");
+  });
+
+  add_named_task("password confirmation matching autocomplete info gets ignored there are too many fields in between, even if has autocomplete info", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form7);
+    await triggerPasswordGeneration(form);
+    is(form.pwordNext.value, "", "Value of the confirm field has not been filled");
+  });
+
+  add_named_task("password confirmation matching autocomplete info gets ignored there are too many disabled fields in between, even if has autocomplete info", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form8);
+    await triggerPasswordGeneration(form);
+    is(form.pwordNext.value, "", "Value of the confirm field has not been filled");
+  });
+
+  add_named_task("password confirmation matching autocomplete info gets filled even if there are many hidden fields in between", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form9);
+    await triggerPasswordGeneration(form);
+    is(form.pwordNext.value, form.pword.value, "Value of the confirm field has been filled with generated password");
+  });
+
+  add_named_task("do not fill third password field after the confirm-password field", async () => {
+    await resetLoginsAndGeneratedPasswords();
+    const form = setContentForTask(formTemplates.form10);
+    await triggerPasswordGeneration(form);
+    is(form.pwordExtra.value, "", "Value of the additional confirm field has not been filled");
+  });
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation_telemetry.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation_telemetry.html
new file mode 100644
index 0000000000..4bbba09483
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_generation_telemetry.html
@@ -0,0 +1,309 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test telemetry on autofill and autocomplete on autocomplete=new-password fields</title>
+  <!-- This test assumes that telemetry events are not cleared after the `setup` task. -->
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <script src="../../../satchel/test/satchel_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+Login Manager test: telemetry events during autofill with password generation on `autocomplete=new-password` fields.
+
+<template id="form1-template">
+  <form id="form1" action="https://autofill">
+    <input type="text" name="uname">
+    <input type="password" name="p">
+    <button type="submit" name="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form2-template">
+  <form id="form2" action="https://autofill">
+    <input type="text" name="uname">
+    <input type="password" name="password" autocomplete="new-password">
+    <button type="submit" name="submit">Submit</button>
+  </form>
+</template>
+
+<template id="form3-template">
+  <form id="form3" action="https://autofill">
+    <input type="text" name="username">
+    <label>New password<input type="password" name="password"></label>
+    <button type="submit" name="submit">Submit</button>
+  </form>
+</template>
+
+<script class="testbody" type="text/javascript">
+  const { TestUtils } = SpecialPowers.ChromeUtils.importESModule(
+    "resource://testing-common/TestUtils.sys.mjs"
+  );
+
+  const formTemplates = {
+    form1: document.getElementById("form1-template"),
+    form2: document.getElementById("form2-template"),
+    form3: document.getElementById("form3-template"),
+  };
+
+  const dateAndTimeFormatter = new SpecialPowers.Services.intl.DateTimeFormat(undefined, {
+    dateStyle: "medium",
+  });
+
+  const TelemetryFilterPropsUsed = Object.freeze({
+    category: "pwmgr",
+    method: "autocomplete_field",
+    object: "generatedpassword",
+  });
+
+  const TelemetryFilterPropsShown = Object.freeze({
+    category: "pwmgr",
+    method: "autocomplete_shown",
+    object: "generatedpassword",
+  });
+
+  async function waitForTelemetryEventsCondition(cond, options = {},
+                                                 errorMsg = "waitForTelemetryEventsCondition timed out", maxTries = 200) {
+    return TestUtils.waitForCondition(async () => {
+      let events = await getTelemetryEvents(options);
+      let result;
+      try {
+        result = cond(events);
+        info("waitForTelemetryEventsCondition, result: " + result);
+      } catch (e) {
+        info("waitForTelemetryEventsCondition caught exception, got events: " + JSON.stringify(events));
+        ok(false, `${e}\n${e.stack}`);
+      }
+      return result ? events : null;
+    }, errorMsg, maxTries);
+  }
+
+  async function showACPopup(formNumber, expectedACLabels) {
+    const autocompleteItems = await popupByArrowDown();
+    checkAutoCompleteResults(autocompleteItems, expectedACLabels,
+                             window.location.host, "Check all rows are correct");
+  }
+
+  async function checkTelemetryEventsPWGenShown(expectedPWGenTelemetryEvents) {
+    info(`showed generated password option, check there are now ${expectedPWGenTelemetryEvents} generatedpassword telemetry events`);
+    await waitForTelemetryEventsCondition(events => {
+      return events.length == expectedPWGenTelemetryEvents;
+    }, { process: "parent", filterProps: TelemetryFilterPropsShown }, `Wait for there to be ${expectedPWGenTelemetryEvents} shown telemetry events`);
+  }
+
+  async function checkTelemetryEventsPWGenUsed(expectedPWGenTelemetryEvents) {
+    info("filled generated password again, ensure we don't record another generatedpassword autocomplete telemetry event");
+    let telemetryEvents;
+    try {
+      telemetryEvents = await waitForTelemetryEventsCondition(events => events.length == expectedPWGenTelemetryEvents + 1,
+                                                              { process: "parent", filterProps: TelemetryFilterPropsUsed },
+                                                              `Wait for there to be ${expectedPWGenTelemetryEvents + 1} used events`, 50);
+    } catch (ex) {}
+    ok(!telemetryEvents, `Expected to timeout waiting for there to be ${expectedPWGenTelemetryEvents + 1} events`);
+  }
+
+  function clearGeneratedPasswords() {
+    const { LoginManagerParent } = ChromeUtils.importESModule(
+      "resource://gre/modules/LoginManagerParent.sys.mjs"
+    );
+    if (LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin()) {
+      LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+    }
+  }
+
+  add_setup(async () => {
+    let useEvents = await getTelemetryEvents({ process: "parent", filterProps: TelemetryFilterPropsUsed, clear: true });
+    is(useEvents.length, 0, "Expect 0 use events");
+    let showEvents = await getTelemetryEvents({ process: "parent", filterProps: TelemetryFilterPropsShown, clear: true });
+    is(showEvents.length, 0, "Expect 0 show events");
+    let acEvents = await getTelemetryEvents({ process: "parent", filterProps: TelemetryFilterPropsAC, clear: true });
+    is(acEvents.length, 0, "Expect 0 autocomplete events");
+  });
+
+  add_named_task("autofill autocomplete username no generation", async () => {
+    await setPreferencesForTask(
+      ["signon.generation.available", false],
+      ["signon.generation.enabled", false],
+    );
+    await setStoredLoginsDuringTask([location.origin, "https://autofill", null, "user1", "pass1"]);
+
+    const form = setContentForTask(formTemplates.form2);
+    const autofillResult = await formAutofillResult(form.id);
+    is(autofillResult, "password_autocomplete_new_password", "form has not been filled due to password_autocomplete_new_password");
+
+    form.uname.focus();
+
+    const [acEvent] = await waitForTelemetryEventsCondition(events => {
+      return events.length == 1;
+    }, { process: "parent", filterProps: TelemetryFilterPropsAC, clear: true }, `Wait for there to be 1 autocomplete telemetry event`);
+    checkACTelemetryEvent(acEvent, form.uname, {
+      "hadPrevious": "0",
+      "login": "1",
+      "loginsFooter": "1"
+    });
+  });
+
+  add_named_task("filling out two forms one after the other", async () => {
+    await setPreferencesForTask(
+      ["signon.generation.available", true],
+      ["signon.generation.enabled", true],
+    );
+
+    const formsToTest = [
+      {
+        num: 2,
+        template: formTemplates.form2
+      },
+      {
+        num: 3,
+        template: formTemplates.form3
+      }
+    ];
+
+    // Bug 1616356 and Bug 1548878: Recorded once per origin
+    let expectedPWGenTelemetryEvents = 0;
+     // Bug 1619498: Recorded once every time the autocomplete popup is shown
+    let expectedACShownTelemetryEvents = 0;
+
+    for (const { num: formNumber, template } of formsToTest) {
+      runInParent(clearGeneratedPasswords);
+      await setStoredLoginsAsync([location.origin, "https://autofill", null, "user1", "pass1"]);
+
+      const form = setContentForTask(template);
+      await promiseFormsProcessedInSameProcess();
+      form.reset();
+
+      form.password.focus();
+
+      await showACPopup(formNumber, [
+        "user1",
+        "Use a Securely Generated Password",
+      ]);
+      expectedPWGenTelemetryEvents++;
+      expectedACShownTelemetryEvents++;
+
+      await checkTelemetryEventsPWGenShown(expectedPWGenTelemetryEvents);
+      let acEvents = await waitForTelemetryEventsCondition(events => {
+        return events.length == expectedACShownTelemetryEvents;
+      }, { process: "parent", filterProps: TelemetryFilterPropsAC }, `Wait for there to be ${expectedACShownTelemetryEvents} autocomplete telemetry event(s)`);
+      checkACTelemetryEvent(acEvents[expectedACShownTelemetryEvents - 1], form.password, {
+        "generatedPasswo": "1",
+        "hadPrevious": "0",
+        "login": "1",
+        "loginsFooter": "1"
+      });
+
+      synthesizeKey("KEY_ArrowDown");
+      synthesizeKey("KEY_Enter");
+      // Can't use promiseFormsProcessedInSameProcess() when autocomplete fills the field directly.
+      await SimpleTest.promiseWaitForCondition(() => form.password.value == "pass1", "Check pw filled");
+
+      // No autocomplete results should appear for non-empty pw fields.
+      await noPopupByArrowDown();
+
+      info("Removing all logins to test auto-saving of generated passwords");
+      await LoginManager.removeAllUserFacingLogins();
+
+      while (form.password.value) {
+        synthesizeKey("KEY_Backspace");
+      }
+
+      info("This time select the generated password");
+      await showACPopup(formNumber, [
+        "Use a Securely Generated Password",
+      ]);
+      expectedACShownTelemetryEvents++;
+
+      await checkTelemetryEventsPWGenShown(expectedPWGenTelemetryEvents);
+      acEvents = await waitForTelemetryEventsCondition(events => {
+        return events.length == expectedACShownTelemetryEvents;
+      }, { process: "parent", filterProps: TelemetryFilterPropsAC }, `Wait for there to be ${expectedACShownTelemetryEvents} autocomplete telemetry event(s)`);
+      checkACTelemetryEvent(acEvents[expectedACShownTelemetryEvents - 1], form.password, {
+        "generatedPasswo": "1",
+        "hadPrevious": "0",
+        "loginsFooter": "1"
+      });
+
+      synthesizeKey("KEY_ArrowDown");
+      let storageAddPromise = promiseStorageChanged(["addLogin"]);
+      synthesizeKey("KEY_Enter");
+
+      info("waiting for the password field to be filled with the generated password");
+      await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check generated pw filled");
+      info("Wait for generated password to be added to storage");
+      await storageAddPromise;
+
+      let logins = await LoginManager.getAllLogins();
+      let timePasswordChanged = logins[logins.length - 1].timePasswordChanged;
+      let time = dateAndTimeFormatter.format(new Date(timePasswordChanged));
+      const LABEL_NO_USERNAME = "No username (" + time + ")";
+
+      info("Check field is masked upon blurring");
+      synthesizeKey("KEY_Tab"); // blur
+      synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+      // Remove selection for OS where the whole value is selected upon focus.
+      synthesizeKey("KEY_ArrowRight");
+
+      while (form.password.value) {
+        synthesizeKey("KEY_Backspace");
+      }
+
+      info("Blur the empty field to trigger a 'change' event");
+      synthesizeKey("KEY_Tab"); // blur
+      synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+
+      info("Type a single character after blanking");
+      synthesizeKey("@");
+
+      info("Blur the single-character field to trigger a 'change' event");
+      synthesizeKey("KEY_Tab"); // blur
+      synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+      synthesizeKey("KEY_Backspace"); // Blank the field again
+
+      await showACPopup(formNumber, [
+        LABEL_NO_USERNAME,
+        "Use a Securely Generated Password",
+      ]);
+      expectedACShownTelemetryEvents++;
+
+      synthesizeKey("KEY_ArrowDown");
+      synthesizeKey("KEY_ArrowDown");
+      synthesizeKey("KEY_Enter");
+      await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check generated pw filled");
+
+      await checkTelemetryEventsPWGenUsed(expectedPWGenTelemetryEvents);
+
+      info("filling the saved login to ensure the field is masked again");
+
+      while (form.password.value) {
+        synthesizeKey("KEY_Backspace");
+      }
+
+      info("Blur the field to trigger a 'change' event again");
+      synthesizeKey("KEY_Tab"); // blur
+      synthesizeKey("KEY_Tab", { shiftKey: true }); // focus again
+      // Remove selection for OS where the whole value is selected upon focus.
+      synthesizeKey("KEY_ArrowRight");
+
+      await showACPopup(formNumber, [
+        LABEL_NO_USERNAME,
+        "Use a Securely Generated Password",
+      ]);
+      expectedACShownTelemetryEvents++;
+
+      synthesizeKey("KEY_ArrowDown");
+      synthesizeKey("KEY_Enter");
+      await SimpleTest.promiseWaitForCondition(() => !!form.password.value, "Check saved generated pw filled");
+      synthesizeKey("KEY_Tab"); // blur
+      synthesizeKey("KEY_Tab", { shiftKey: true }); // focus
+    }
+  });
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_open.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_open.html
new file mode 100644
index 0000000000..e792aa19af
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_password_open.html
@@ -0,0 +1,90 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test password field autocomplete footer with and without logins</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<div id="content"></div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: Test password field autocomplete footer with and without logins **/
+
+add_task(async function test_no_autofill() {
+  await setStoredLoginsAsync(
+    [location.origin, "", null, "user-1", "pass-1", "uname", "pword"],
+    [location.origin, "", null, "user-2", "pass-2", "uname", "pword"]
+  );
+  const form = createLoginForm();
+  await promiseFormsProcessedInSameProcess();
+
+  // Make sure initial form is empty as autofill shouldn't happen in the sandboxed frame.
+  checkLoginForm(form.uname, "", form.pword, "");
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is initially closed");
+});
+
+add_task(async function test_two_logins() {
+  await setStoredLoginsAsync(
+    [location.origin, "", null, "user-1", "pass-1", "uname", "pword"],
+    [location.origin, "", null, "user-2", "pass-2", "uname", "pword"]
+  );
+  const form = createLoginForm();
+  await promiseFormsProcessedInSameProcess();
+
+  await popupBy(() => form.uname.focus());
+
+  // popup on the password field should open upon focus
+  let results = await popupBy(() => synthesizeKey("KEY_Tab"));
+
+  let popupState = await getPopupState();
+  is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
+
+  let expectedMenuItems = [
+    "user-1",
+    "user-2",
+  ];
+  checkAutoCompleteResults(results, expectedMenuItems, window.location.host, "Check all menuitems are displayed correctly.");
+
+  checkLoginForm(form.uname, "", form.pword, "");
+});
+
+add_task(async function test_zero_logins() {
+  // no logins stored
+  await setStoredLoginsAsync();
+  const form = createLoginForm();
+  await promiseFormsProcessedInSameProcess();
+
+  form.uname.focus();
+
+  let shownPromise = popupBy().then(() => ok(false, "Should not have shown"));
+  // Popup on the password field should NOT automatically open upon focus when there are no saved logins.
+  synthesizeKey("KEY_Tab"); // focus the password field
+  SimpleTest.requestFlakyTimeout("Giving a chance for the unexpected popup to show");
+  let autocompleteItems = await Promise.race([
+    shownPromise,
+    new Promise(resolve => setTimeout(resolve, 2000)), // Wait 2s for the popup to appear
+  ]);
+
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is still closed");
+
+  checkLoginForm(form.uname, "", form.pword, "");
+  info("arrow down should still open the popup");
+  autocompleteItems = await popupByArrowDown();
+  checkAutoCompleteResults(autocompleteItems, [], window.location.host, "Check only footer is displayed.");
+  checkLoginForm(form.uname, "", form.pword, "");
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_sandboxed.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_sandboxed.html
new file mode 100644
index 0000000000..229791109a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_sandboxed.html
@@ -0,0 +1,70 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test form field autocomplete in sandboxed documents (null principal)</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content">
+  <iframe id="sandboxed"
+          sandbox=""
+          src="form_basic.html"></iframe>
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: form field autocomplete in sandboxed documents (null principal) **/
+
+let sandboxed = document.getElementById("sandboxed");
+let uname;
+let pword;
+let hostname;
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [window.location.origin, "", null, "tempuser1", "temppass1", "uname", "pword"]
+  );
+  let frameWindow = SpecialPowers.wrap(sandboxed).contentWindow;
+  // Can't use SimpleTest.promiseFocus as it doesn't work with the sandbox.
+  await SimpleTest.promiseWaitForCondition(() => {
+    return frameWindow.document.readyState == "complete" && frameWindow.location.href != "about:blank";
+  }, "Check frame is loaded");
+  let frameDoc = SpecialPowers.wrap(sandboxed).contentDocument;
+  uname = frameDoc.getElementById("form-basic-username");
+  pword = frameDoc.getElementById("form-basic-password");
+  hostname = frameDoc.documentURIObject.host;
+});
+
+add_task(async function test_no_autofill() {
+  // Make sure initial form is empty as autofill shouldn't happen in the sandboxed frame.
+  checkLoginForm(uname, "", pword, "");
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is initially closed");
+});
+
+add_task(async function test_autocomplete_warning_no_logins() {
+  const { items } = await openPopupOn(pword);
+
+  let popupState = await getPopupState();
+  is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
+
+  let expectedMenuItems = [
+    "This connection is not secure. Logins entered here could be compromised. Learn More",
+  ];
+  checkAutoCompleteResults(items, expectedMenuItems, hostname, "Check all menuitems are displayed correctly.");
+
+  checkLoginForm(uname, "", pword, "");
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_tab_between_fields.html b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_tab_between_fields.html
new file mode 100644
index 0000000000..4a0aaff0b3
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autocomplete_tab_between_fields.html
@@ -0,0 +1,167 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autocomplete behavior when tabbing between form fields</title>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content"></div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+const { TestUtils } = SpecialPowers.ChromeUtils.importESModule(
+  "resource://testing-common/TestUtils.sys.mjs"
+);
+
+const availableLogins = {
+  "exampleUser1": [location.origin, "https://autofill", null, "user1", "pass1", "uname", "pword"],
+  "subdomainUser1": ["https://sub." + location.host, "https://autofill", null, "user1", "pass1", "uname", "pword"],
+  "emptyUsername": [location.origin, "https://autofill", null, "", "pass2", "uname", "pword"],
+}
+
+const tests = [
+  {
+    name: "single_login_exact_origin_no_inputs",
+    logins: ["exampleUser1"],
+    expectedAutofillUsername: "user1",
+    expectedAutofillPassword: "pass1",
+    expectedACLabels: ["user1"],
+    typeUsername: null,
+    expectedTabbedUsername: "",
+    expectedTabbedPassword: "",
+  },
+  {
+    name: "single_login_exact_origin_initial_letter",
+    logins: ["exampleUser1"],
+    expectedAutofillUsername: "user1",
+    expectedAutofillPassword: "pass1",
+    expectedACLabels: ["user1"],
+    typeUsername: "u",
+    expectedTabbedUsername: "u",
+    expectedTabbedPassword: "",
+  },
+  {
+    name: "single_login_exact_origin_type_username",
+    logins: ["exampleUser1"],
+    expectedAutofillUsername: "user1",
+    expectedAutofillPassword: "pass1",
+    expectedACLabels: ["user1"],
+    typeUsername: "user1",
+    expectedTabbedUsername: "user1",
+    expectedTabbedPassword: "pass1",
+  },
+  {
+    name: "single_login_subdomain_no_inputs",
+    logins: ["subdomainUser1"],
+    expectedAutofillUsername: "",
+    expectedAutofillPassword: "",
+    expectedACLabels: ["user1"],
+    typeUsername: null,
+    expectedTabbedUsername: "",
+    expectedTabbedPassword: "",
+  },
+  {
+    name: "single_login_subdomain_type_username",
+    logins: ["subdomainUser1"],
+    expectedAutofillUsername: "",
+    expectedAutofillPassword: "",
+    expectedACLabels: ["user1"],
+    typeUsername: "user1",
+    expectedTabbedUsername: "user1",
+    expectedTabbedPassword: "",
+  },
+  {
+    name: "two_logins_one_with_empty_username",
+    logins: ["exampleUser1", "emptyUsername"],
+    expectedAutofillUsername: "user1",
+    expectedAutofillPassword: "pass1",
+    expectedACLabels: ["user1"],
+    typeUsername: "",
+    expectedTabbedUsername: "",
+    expectedTabbedPassword: "",
+  },
+];
+
+add_setup(async () => {
+  await SpecialPowers.pushPrefEnv({"set": [["signon.includeOtherSubdomainsInLookup", true]]});
+});
+
+async function testResultOfTabInteractions(testData) {
+  const logins = testData.logins.map(name => availableLogins[name]);
+  await setStoredLoginsAsync(...logins);
+
+  const form = createLoginForm({
+    action: "https://autofill"
+  });
+  await promiseFormsProcessedInSameProcess();
+
+  await SimpleTest.promiseFocus(window);
+
+  // check autofill results
+  checkForm(1, testData.expectedAutofillUsername, testData.expectedAutofillPassword);
+
+  SpecialPowers.wrap(form.pword).setUserInput("");
+  SpecialPowers.wrap(form.uname).setUserInput("");
+
+  info("Placing focus in the password field");
+  form.pword.focus();
+  await synthesizeKey("KEY_Tab", { shiftKey: true }); // blur pw, focus un
+
+  // moving focus shouldn't change anything
+  await ensureLoginFormStaysFilledWith(form.uname, "", form.pword, "");
+
+  info("waiting for AC results");
+  const results = await popupByArrowDown();
+  info("checking results");
+  checkAutoCompleteResults(results, testData.expectedACLabels,
+                           window.location.host, "Check all rows are correct");
+
+  if (testData.typeUsername) {
+    await sendString(testData.typeUsername);
+  }
+
+  // don't select anything from the AC menu
+  await synthesizeKey("KEY_Escape");
+  await TestUtils.waitForCondition(async () => {
+    let popupState = await getPopupState();
+    return !popupState.open;
+  }, "AutoComplete popup should have closed");
+
+  await synthesizeKey("KEY_Tab");
+
+  // wait until username and password are automatically filled in with the
+  // expected values...
+  await TestUtils.waitForCondition(() => {
+    return form.uname.value === testData.expectedTabbedUsername & form.pword.value === testData.expectedTabbedPassword;
+  }, "Username and password field should be filled");
+
+  // ...and if the value is not different from the original value in the form,
+  // make sure that the form keeps its values
+  if (testData.expectedTabbedPassword === "") {
+      await ensureLoginFormStaysFilledWith(form.uname, testData.expectedTabbedUsername, form.pword, testData.expectedTabbedPassword);
+  }
+
+  ok(form.pword.matches("input:focus"), "pword field is focused");
+}
+
+for (const testData of tests) {
+  const tmp = {
+    async [testData.name]() {
+      await testResultOfTabInteractions(testData);
+    },
+  };
+  add_task(tmp[testData.name]);
+}
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_autocomplete_types.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_autocomplete_types.html
new file mode 100644
index 0000000000..c44d5a25ef
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_autocomplete_types.html
@@ -0,0 +1,112 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofilling with autocomplete types (username, off, cc-type, etc.)</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Test autofilling with autocomplete types (username, off, cc-type, etc.)
+
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+/*
+  Test for Login Manager: Skip over inappropriate autcomplete types when finding username field
+ */
+
+const win = window.open("about:blank");
+const loadPromise = loadFormIntoWindow(location.origin, `
+  <form id="form0" action="https://autocomplete">
+    <input  type="text" name="uname">
+    <input  type="text" autocomplete="">
+    <input  type="password" name="pword">
+    <button type="submit">Submit</button>
+  </form>
+
+  <form id="form1" action="https://autocomplete">
+    <input  type="text" name="uname">
+    <input  type="text" autocomplete="username">
+    <input  type="password" name="pword">
+    <button type="submit">Submit</button>
+  </form>
+
+  <form id="form2" action="https://autocomplete">
+    <input  type="text" name="uname">
+    <input  type="text" autocomplete="off" name="acfield">
+    <input  type="password" name="pword">
+    <button type="submit">Submit</button>
+  </form>
+
+  <form id="form3" action="https://autocomplete">
+    <input  type="text" name="uname">
+    <input  type="text" autocomplete="on" name="acfield">
+    <input  type="password" name="pword">
+    <button type="submit">Submit</button>
+  </form>
+
+  <form id="form4" action="https://autocomplete">
+    <input  type="text" name="uname">
+    <input  type="text" autocomplete="nosuchtype" name="acfield">
+    <input  type="password" name="pword">
+    <button type="submit">Submit</button>
+  </form>
+
+  <form id="form5" action="https://autocomplete">
+    <input  type="text" name="uname">
+    <input  type="text" autocomplete="email" name="acfield">
+    <input  type="password" name="pword">
+    <button type="submit">Submit</button>
+  </form>
+
+  <form id="form6" action="https://autocomplete">
+    <input  type="text" name="uname">
+    <input  type="text" autocomplete="tel" name="acfield">
+    <input  type="password" name="pword">
+    <button type="submit">Submit</button>
+  </form>
+
+  <form id="form7" action="https://autocomplete">
+    <input  type="text" name="uname">
+    <input  type="text" autocomplete="tel-national" name="acfield">
+    <input  type="password" name="pword">
+    <button type="submit">Submit</button>
+  </form>
+
+  <!-- Begin forms where the first field is skipped for the username -->
+
+  <form id="form101" action="https://autocomplete">
+    <input  type="text" name="uname">
+    <input  type="text" autocomplete="cc-number" name="acfield">
+    <input  type="password" name="pword">
+    <button type="submit">Submit</button>
+  </form>`, win, 8);
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [window.location.origin, "https://autocomplete", null, "testuser@example.com", "testpass1", "", ""]
+  );
+  SimpleTest.registerCleanupFunction(() => win.close());
+});
+
+/* Tests for autofill of single-user forms with various autocomplete types */
+add_task(async function test_autofill_autocomplete_types() {
+  await loadPromise;
+  await checkLoginFormInFrameWithElementValues(win, 0, null, "testuser@example.com", "testpass1");
+  await checkLoginFormInFrameWithElementValues(win, 1, null, "testuser@example.com", "testpass1");
+  await checkLoginFormInFrameWithElementValues(win, 2, null, "testuser@example.com", "testpass1");
+  await checkLoginFormInFrameWithElementValues(win, 3, null, "testuser@example.com", "testpass1");
+  await checkLoginFormInFrameWithElementValues(win, 4, null, "testuser@example.com", "testpass1");
+  await checkLoginFormInFrameWithElementValues(win, 5, null, "testuser@example.com", "testpass1");
+  await checkLoginFormInFrameWithElementValues(win, 6, null, "testuser@example.com", "testpass1");
+  await checkLoginFormInFrameWithElementValues(win, 7, null, "testuser@example.com", "testpass1");
+  await checkLoginFormInFrameWithElementValues(win, 101, "testuser@example.com", null, "testpass1");
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_different_formActionOrigin.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_different_formActionOrigin.html
new file mode 100644
index 0000000000..1ea43f6a8f
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_different_formActionOrigin.html
@@ -0,0 +1,91 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofill on an HTTPS page using upgraded HTTP logins with different formActionOrigin</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script>
+const MISSING_ACTION_PATH = TESTS_DIR + "mochitest/form_basic.html";
+
+const chromeScript = runChecksAfterCommonInit(false);
+
+let nsLoginInfo = SpecialPowers.wrap(SpecialPowers.Components).Constructor("@mozilla.org/login-manager/loginInfo;1",
+                                                                           SpecialPowers.Ci.nsILoginInfo,
+                                                                           "init");
+</script>
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+let origin = window.location.origin;
+let suborigin = "http://sub." + window.location.host;
+
+let win = window.open("about:blank");
+SimpleTest.registerCleanupFunction(() => win.close());
+
+async function prepareLoginsAndProcessForm(url, logins = []) {
+  await LoginManager.removeAllUserFacingLogins();
+
+  let dates = Date.now();
+  for (let login of logins) {
+    SpecialPowers.do_QueryInterface(login, SpecialPowers.Ci.nsILoginMetaInfo);
+    // Force all dates to be the same so they don't affect things like deduping.
+    login.timeCreated = login.timePasswordChanged = login.timeLastUsed = dates;
+    await LoginManager.addLoginAsync(login);
+  }
+
+  let processedPromise = promiseFormsProcessed();
+  win.location = url;
+  await processedPromise;
+}
+
+add_task(async function test_formActionOrigin_wildcard_should_autofill() {
+  await prepareLoginsAndProcessForm(origin + MISSING_ACTION_PATH, [
+    new nsLoginInfo(origin, "", null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+
+  await checkLoginFormInFrame(win, "form-basic-username", "name2", "form-basic-password", "pass2");
+});
+
+add_task(async function test_formActionOrigin_different_shouldnt_autofill() {
+  await prepareLoginsAndProcessForm(origin + MISSING_ACTION_PATH, [
+    new nsLoginInfo(origin, "https://example.net", null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+
+
+  await checkLoginFormInFrame(win, "form-basic-username", "", "form-basic-password", "");
+});
+
+add_task(async function test_formActionOrigin_subdomain_should_autofill() {
+  await prepareLoginsAndProcessForm(origin + MISSING_ACTION_PATH, [
+    new nsLoginInfo(origin, suborigin, null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+
+  await checkLoginFormInFrame(win, "form-basic-username", "name2", "form-basic-password", "pass2");
+});
+
+add_task(async function test_origin_subdomain_should_not_autofill() {
+  await prepareLoginsAndProcessForm(origin + MISSING_ACTION_PATH, [
+    new nsLoginInfo(suborigin, origin, null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+
+  await checkLoginFormInFrame(win, "form-basic-username", "", "form-basic-password", "");
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_different_subdomain.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_different_subdomain.html
new file mode 100644
index 0000000000..66c6ab3536
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_different_subdomain.html
@@ -0,0 +1,150 @@
+xcod<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofill on an HTTPS page using logins with different eTLD+1</title>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script>
+const MISSING_ACTION_PATH = TESTS_DIR + "mochitest/form_basic.html";
+
+const chromeScript = runChecksAfterCommonInit(false);
+
+let nsLoginInfo = SpecialPowers.wrap(SpecialPowers.Components).Constructor("@mozilla.org/login-manager/loginInfo;1",
+                                                                           SpecialPowers.Ci.nsILoginInfo,
+                                                                           "init");
+</script>
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content">
+  <iframe></iframe>
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+let iframe = SpecialPowers.wrap(document.getElementsByTagName("iframe")[0]);
+let win = window.open("about:blank");
+SimpleTest.registerCleanupFunction(() => win.close());
+
+let origin = window.location.origin;
+let otherOrigin = "https://foobar." + window.location.host;
+let oldOrigin = "https://old." + window.location.host;
+
+async function checkWindowLoginForm(expectedUsername, expectedPassword) {
+  return SpecialPowers.spawn(win, [expectedUsername, expectedPassword], function(un, pw) {
+    let doc = this.content.document;
+    Assert.equal(doc.querySelector("#form-basic-username").value, un, "Check username value");
+    Assert.equal(doc.querySelector("#form-basic-password").value, pw, "Check password value");
+  });
+}
+
+async function prepareLogins(logins = []) {
+  await LoginManager.removeAllUserFacingLogins();
+
+  let dates = Date.now();
+  for (let login of logins) {
+    SpecialPowers.do_QueryInterface(login, SpecialPowers.Ci.nsILoginMetaInfo);
+    // Force all dates to be the same so they don't affect things like deduping.
+    login.timeCreated = login.timePasswordChanged = login.timeLastUsed = dates;
+    await LoginManager.addLoginAsync(login);
+  }
+}
+
+async function formReadyInFrame(url) {
+  let processedPromise = promiseFormsProcessed();
+  iframe.src = url;
+  return processedPromise;
+}
+
+async function formReadyInWindow(url) {
+  let processedPromise = promiseFormsProcessedInSameProcess();
+  win.location = url;
+  return processedPromise;
+}
+
+add_task(async function test_login_with_different_subdomain_shouldnt_autofill_wildcard_formActionOrigin() {
+  await prepareLogins([
+    new nsLoginInfo(otherOrigin, "", null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+  await formReadyInWindow(origin + MISSING_ACTION_PATH);
+
+  await checkWindowLoginForm("", "");
+});
+
+add_task(async function test_login_with_different_subdomain_shouldnt_autofill_same_domain_formActionOrigin() {
+  await prepareLogins([
+    new nsLoginInfo(otherOrigin, origin, null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+  await formReadyInWindow(origin + MISSING_ACTION_PATH);
+
+  await checkWindowLoginForm("", "");
+});
+
+add_task(async function test_matching_logins_with_different_subdomain_and_matching_domain_should_autofill() {
+  await prepareLogins([
+    new nsLoginInfo(origin, origin, null,
+                    "name2", "pass2", "uname", "pword"),
+    new nsLoginInfo(oldOrigin, origin, null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+  await formReadyInWindow(origin + MISSING_ACTION_PATH);
+
+  await checkWindowLoginForm("name2", "pass2");
+});
+
+add_task(async function test_login_with_different_subdomain_shouldnt_autofill_different_subdomain_formActionOrigin() {
+  await prepareLogins([
+    new nsLoginInfo(otherOrigin, otherOrigin, null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+  await formReadyInWindow(origin + MISSING_ACTION_PATH);
+
+  await checkWindowLoginForm("", "");
+});
+
+add_task(async function test_login_with_different_subdomain_shouldnt_autofill_different_domain_formActionOrigin() {
+  await prepareLogins([
+    new nsLoginInfo(otherOrigin, "https://example.net", null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+  await formReadyInWindow(origin + MISSING_ACTION_PATH);
+
+  await checkWindowLoginForm("", "");
+});
+
+add_task(async function test_login_with_same_origin_shouldnt_autofill_cross_origin_iframe() {
+  await SimpleTest.promiseFocus(window);
+
+  async function checkIframeLoginForm(expectedUsername, expectedPassword) {
+    return SpecialPowers.spawn(getIframeBrowsingContext(window, 0), [expectedUsername, expectedPassword], function(un, pw) {
+        var u = this.content.document.getElementById("form-basic-username");
+        var p = this.content.document.getElementById("form-basic-password");
+        Assert.equal(u.value, un, "Check username value");
+        Assert.equal(p.value, pw, "Check password value");
+    });
+  }
+
+  // We need an origin that is supported by the test framework to be able to load the
+  // cross-origin form into the iframe.
+  let crossOrigin = "https://test1.example.com";
+  info(`Top level frame origin: ${origin}. Iframe and login origin: ${crossOrigin}.`);
+  await prepareLogins([
+    new nsLoginInfo(crossOrigin, crossOrigin, null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+  await formReadyInFrame(crossOrigin + MISSING_ACTION_PATH);
+
+  await checkIframeLoginForm("", "");
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_from_bfcache.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_from_bfcache.html
new file mode 100644
index 0000000000..d0fcb16e18
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_from_bfcache.html
@@ -0,0 +1,58 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofilling documents restored from the back/forward cache (bfcache)</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body onload="test_crossOriginBfcacheRestore();">
+<p id="display"></p>
+
+<div id="content">
+  <a id="next" href="https://example.org/tests/toolkit/components/passwordmgr/test/mochitest/file_history_back.html" target="loginWin">Next</a>
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+SimpleTest.waitForExplicitFinish();
+
+/*
+ * The test opens a new window and updates login information. Then
+ * a new page is loaded and it goes immediately back. The initial page
+ * should be coming out from the bfcache and the form control values should be
+ * the ones filled during the initial load.
+ */
+async function test_crossOriginBfcacheRestore() {
+  // If Fission is disabled, the pref is no-op.
+  await SpecialPowers.pushPrefEnv({set: [["fission.bfcacheInParent", true]]});
+
+  var bc = new BroadcastChannel("form_basic_bfcache");
+  window.open("form_basic_bfcache.html", "", "noopener");
+  var pageshowCount = 0;
+  bc.onmessage = function(event) {
+    if (event.data.type == "pageshow") {
+      ++pageshowCount;
+      if (pageshowCount == 1) {
+        is(event.data.persisted, false, "Initial load");
+        bc.postMessage("nextpage");
+      } else if (pageshowCount == 2) {
+        is(event.data.persisted, true, "Should have persisted the page.");
+        bc.postMessage("close");
+      }
+    } else if (event.data.type == "is") {
+      is(event.data.value1, event.data.value2, event.data.message);
+    } else if (event.data.type == "ok") {
+      is(event.data.value, event.data.message);
+    } else if (event.data == "closed") {
+      bc.close();
+      SimpleTest.finish();
+    }
+  }
+
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_hasBeenTypePassword.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_hasBeenTypePassword.html
new file mode 100644
index 0000000000..2139d30e61
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_hasBeenTypePassword.html
@@ -0,0 +1,64 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test no autofill into a password field that is no longer type=password</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+Login Manager test: Test no autofill into a password field that is no longer type=password
+
+<script>
+let DEFAULT_ORIGIN = window.location.origin;
+
+/** Test for Login Manager: Test no autofill into a password field that is no longer type=password **/
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [DEFAULT_ORIGIN, "https://autofill", null, "user1", "pass1"]
+  );
+});
+
+
+// As a control, test that autofill is working on this page.
+add_task(async function test_autofill_control() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <form id="form1" action="https://autofill">
+      <p>This is form 1.</p>
+      <input id="username-1" type="text"       name="uname">
+      <input id="password-1" type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+    </form>`, win);
+  await checkLoginFormInFrame(win, "username-1", "user1", "password-1", "pass1");
+});
+
+add_task(async function test_no_autofill() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  // Synchronously change the password field type to text before the fill happens.
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <form id="form1" action="https://autofill">
+      <p>This is form 1.</p>
+      <input id="username-1" type="text"       name="uname">
+      <input id="password-1" type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+    </form>`, win, 1, () => {
+      this.content.document.getElementById("password-1").type = "text";
+    });
+  await checkLoginFormInFrame(win, "username-1", "", "password-1", "");
+});
+</script>
+
+<p id="display"></p>
+
+<div id="content"></div>
+
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_highlight.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_highlight.html
new file mode 100644
index 0000000000..3ca214841c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_highlight.html
@@ -0,0 +1,58 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test form field autofill highlight</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content">
+<pre id="test">
+<script>
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [window.location.origin, "https://autofill", null, "user1", "pass1", "", ""]
+  );
+});
+
+add_task(async function test_field_highlight_on_autofill() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(window.location.origin, `
+    <form id="form1" action="https://autofill" onsubmit="return false;">
+      <input  type="text"       id="uname">
+      <input  type="password"   id="pword">
+      <button type="submit">Submit</button>
+    </form>`, win);
+
+  await SpecialPowers.spawn(win, [], async function() {
+    let EventUtils = ContentTaskUtils.getEventUtils(this.content);
+    let doc = this.content.document;
+    let username = doc.getElementById("uname");
+    let password = doc.getElementById("pword");
+    ok(username.matches(":autofill"),
+       "Highlight was successfully applied to the username field on page load autofill");
+    ok(password.matches(":autofill"),
+       "Highlight was successfully applied to the password field on page load autofill");
+
+    // Test that initiating a change on the input value will remove the highlight. We check by pressing
+    // the tab key after backspace(by shifting focus to the next element) because the tab key is known to
+    // cause a bug where the highlight is applied once again.
+    username.focus();
+    await EventUtils.synthesizeKey("KEY_Backspace", {}, this.content);
+    await EventUtils.synthesizeKey("KEY_Tab", {}, this.content);
+
+    ok(!username.matches(":autofill"), "Highlight was successfully removed on change in value of username input element");
+
+    await EventUtils.synthesizeKey("KEY_Backspace", {}, this.content);
+    await EventUtils.synthesizeKey("KEY_Tab", {}, this.content);
+    ok(!password.matches(":autofill"), "Highlight was successfully removed on change in value of password input element");
+  });
+});
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_highlight_empty_username.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_highlight_empty_username.html
new file mode 100644
index 0000000000..36fffb480b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_highlight_empty_username.html
@@ -0,0 +1,60 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test that filling an empty username into a form does not highlight the username element</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<script>
+</script>
+<body>
+<p id="display"></p>
+<div id="content">
+<pre id="test">
+<script>
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [window.location.origin, "https://autofill", null, "", "pass1", "", ""]
+  );
+});
+
+add_task(async function test_field_highlight_on_autofill() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(window.location.origin, `
+    <form id="form1" action="https://autofill" onsubmit="return false;">
+      <input  type="text"       id="uname">
+      <input  type="password"   id="pword">
+      <button type="submit">Submit</button>
+    </form>`, win);
+
+  await SpecialPowers.spawn(win, [], async function() {
+    let EventUtils = ContentTaskUtils.getEventUtils(this.content);
+    let doc = this.content.document;
+    let username = doc.getElementById("uname");
+    let password = doc.getElementById("pword");
+    ok(!username.matches(":autofill"),
+          "Highlight was not applied to the username field on page load autofill");
+    ok(password.matches(":autofill"),
+          "Highlight was successfully applied to the password field on page load autofill");
+
+    // Test that initiating a change on the input value will remove the highlight. We check by pressing
+    // the tab key after backspace(by shifting focus to the next element) because the tab key is known to
+    // cause a bug where the highlight is applied once again.
+    username.focus();
+    await EventUtils.synthesizeKey("U", {}, this.content);
+    await EventUtils.synthesizeKey("KEY_Tab", {}, this.content);
+
+    ok(!username.matches(":autofill"), "Highlight is still not present on username element");
+
+    await EventUtils.synthesizeKey("KEY_Backspace", {}, this.content);
+    await EventUtils.synthesizeKey("KEY_Tab", {}, this.content);
+    ok(!password.matches(":autofill"), "Highlight was successfully removed on change in value of password input element");
+  });
+});
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_highlight_username_only_form.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_highlight_username_only_form.html
new file mode 100644
index 0000000000..67892a9ea4
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_highlight_username_only_form.html
@@ -0,0 +1,50 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test that filling a username into a username-only form does highlight the username element</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content">
+<pre id="test">
+<script>
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [window.location.origin, "https://autofill", null, "user1", "pass1", "", ""]
+  );
+});
+
+add_task(async function test_field_highlight_on_autofill() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(window.location.origin, `
+    <form id="form1" action="https://autofill" onsubmit="return false;">
+      <input  type="text" id="uname" autocomplete="username">
+      <button type="submit">Submit</button>
+    </form>`, win);
+
+  await SpecialPowers.spawn(win, [], async function() {
+    let EventUtils = ContentTaskUtils.getEventUtils(this.content);
+    let doc = this.content.document;
+    let username = doc.getElementById("uname");
+    ok(username.matches(":autofill"),
+          "Highlight was successfully applied to the username field on page load autofill");
+
+    // Test that initiating a change on the input value will remove the highlight. We check by pressing
+    // the tab key after backspace(by shifting focus to the next element) because the tab key is known to
+    // cause a bug where the highlight is applied once again.
+    username.focus();
+    await EventUtils.synthesizeKey("KEY_Backspace", {}, this.content);
+    await EventUtils.synthesizeKey("KEY_Tab", {}, this.content);
+
+    ok(!username.matches(":autofill"), "Highlight was successfully removed on change in value of username input element");
+  });
+});
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_https_downgrade.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_https_downgrade.html
new file mode 100644
index 0000000000..091f9c8ad6
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_https_downgrade.html
@@ -0,0 +1,118 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test we don't autofill on an HTTP page using HTTPS logins</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script>
+const MISSING_ACTION_PATH = TESTS_DIR + "mochitest/form_basic.html";
+const SAME_ORIGIN_ACTION_PATH = TESTS_DIR + "mochitest/form_same_origin_action.html";
+
+const chromeScript = runChecksAfterCommonInit(false);
+
+let nsLoginInfo = SpecialPowers.wrap(SpecialPowers.Components).Constructor("@mozilla.org/login-manager/loginInfo;1",
+                                                                           SpecialPowers.Ci.nsILoginInfo,
+                                                                           "init");
+</script>
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+let win = window.open("about:blank");
+SimpleTest.registerCleanupFunction(() => win.close());
+
+async function prepareAndProcessForm(url, login) {
+  let processedPromise = promiseFormsProcessed();
+  win.location = url;
+  info("prepareAndProcessForm, assigned window location: " + url);
+  await processedPromise;
+}
+
+async function checkFormsWithLogin(formUrls, login, expectedUsername, expectedPassword) {
+  await LoginManager.removeAllUserFacingLogins();
+  await LoginManager.addLoginAsync(login);
+
+  for (let url of formUrls) {
+    info("start test_checkNoAutofillOnDowngrade w. url: " + url);
+
+    await prepareAndProcessForm(url);
+    info("form was processed");
+
+    await SpecialPowers.spawn(win, [url, expectedUsername, expectedPassword],
+                              function(urlContent, expectedUsernameContent, expectedPasswordContent) {
+      let doc = this.content.document;
+      let uname = doc.getElementById("form-basic-username");
+      let pword = doc.getElementById("form-basic-password");
+      Assert.equal(uname.value, expectedUsernameContent, `username ${expectedUsernameContent ? "filled" : "not filled"} on ${urlContent}`);
+      Assert.equal(pword.value, expectedPasswordContent, `password ${expectedPasswordContent ? "filled" : "not filled"} on ${urlContent}`);
+    });
+  }
+}
+
+add_setup(async () => {
+  await SpecialPowers.pushPrefEnv({"set": [
+    ["signon.schemeUpgrades", true],
+    ["dom.security.https_first", false],
+    ]});
+});
+
+add_task(async function test_sanityCheckHTTPS() {
+  let login = new nsLoginInfo("https://example.com", "https://example.com", null,
+                              "name1", "pass1", "uname", "pword");
+
+  await checkFormsWithLogin([
+    `https://example.com${MISSING_ACTION_PATH}`,
+    `https://example.com${SAME_ORIGIN_ACTION_PATH}`,
+  ], login, "name1", "pass1");
+});
+
+add_task(async function test_checkNoAutofillOnDowngrade() {
+  let login = new nsLoginInfo("https://example.com", "https://example.com", null,
+                              "name1", "pass1", "uname", "pword");
+  await checkFormsWithLogin([
+    `http://example.com${MISSING_ACTION_PATH}`,
+    `http://example.com${SAME_ORIGIN_ACTION_PATH}`,
+  ], login, "", "");
+});
+
+add_task(async function test_checkNoAutofillOnDowngradeSubdomain() {
+  let login = new nsLoginInfo("https://sub.example.com", "https://example.com", null,
+                              "name1", "pass1", "uname", "pword");
+  todo(false, "await promiseFormsProcessed timesout when test is run with scheme=https");
+  await checkFormsWithLogin([
+    `http://example.com${MISSING_ACTION_PATH}`,
+    `http://example.com${SAME_ORIGIN_ACTION_PATH}`,
+  ], login, "", "");
+});
+
+
+add_task(async function test_checkNoAutofillOnDowngradeDifferentPort() {
+  let login = new nsLoginInfo("https://example.com:8080", "https://example.com", null,
+                              "name1", "pass1", "uname", "pword");
+  await checkFormsWithLogin([
+    `http://example.com${MISSING_ACTION_PATH}`,
+    `http://example.com${SAME_ORIGIN_ACTION_PATH}`,
+  ], login, "", "");
+});
+
+add_task(async function test_checkNoAutofillOnDowngradeSubdomainDifferentPort() {
+  let login = new nsLoginInfo("https://sub.example.com:8080", "https://example.com", null,
+                              "name1", "pass1", "uname", "pword");
+  await checkFormsWithLogin([
+    `https://example.com${MISSING_ACTION_PATH}`,
+    `https://example.com${SAME_ORIGIN_ACTION_PATH}`,
+  ], login, "", "");
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_https_upgrade.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_https_upgrade.html
new file mode 100644
index 0000000000..a8691ebe54
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_https_upgrade.html
@@ -0,0 +1,148 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofill on an HTTPS page using upgraded HTTP logins</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script>
+const MISSING_ACTION_PATH = TESTS_DIR + "mochitest/form_basic.html";
+const CROSS_ORIGIN_SECURE_PATH = TESTS_DIR + "mochitest/form_cross_origin_secure_action.html";
+
+const chromeScript = runChecksAfterCommonInit(false);
+
+let nsLoginInfo = SpecialPowers.wrap(SpecialPowers.Components).Constructor("@mozilla.org/login-manager/loginInfo;1",
+                                                                           SpecialPowers.Ci.nsILoginInfo,
+                                                                           "init");
+</script>
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+let win = window.open("about:blank");
+SimpleTest.registerCleanupFunction(() => win.close());
+
+async function prepareLoginsAndProcessForm(url, logins = []) {
+  await LoginManager.removeAllUserFacingLogins();
+
+  let dates = Date.now();
+  for (let login of logins) {
+    SpecialPowers.do_QueryInterface(login, SpecialPowers.Ci.nsILoginMetaInfo);
+    // Force all dates to be the same so they don't affect things like deduping.
+    login.timeCreated = login.timePasswordChanged = login.timeLastUsed = dates;
+    await LoginManager.addLoginAsync(login);
+  }
+
+  let processedPromise = promiseFormsProcessed();
+  win.location = url;
+  await processedPromise;
+}
+
+add_setup(async () => {
+  await SpecialPowers.pushPrefEnv({"set": [
+    ["signon.schemeUpgrades", true],
+    ["signon.includeOtherSubdomainsInLookup", true],
+  ]});
+});
+
+add_task(async function test_simpleNoDupesNoAction() {
+  await prepareLoginsAndProcessForm("https://example.com" + MISSING_ACTION_PATH, [
+    new nsLoginInfo("http://example.com", "http://example.com", null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+
+  await checkLoginFormInFrame(win,
+                                   "form-basic-username", "name2",
+                                   "form-basic-password", "pass2");
+});
+
+add_task(async function test_simpleNoDupesUpgradeOriginAndAction() {
+  await prepareLoginsAndProcessForm("https://example.com" + CROSS_ORIGIN_SECURE_PATH, [
+    new nsLoginInfo("http://example.com", "http://example.org", null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+
+  await checkLoginFormInFrame(win, "form-basic-username", "name2",
+                                           "form-basic-password", "pass2");
+});
+
+add_task(async function test_simpleNoDupesUpgradeOriginOnly() {
+  await prepareLoginsAndProcessForm("https://example.com" + CROSS_ORIGIN_SECURE_PATH, [
+    new nsLoginInfo("http://example.com", "https://example.org", null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+
+  await checkLoginFormInFrame(win, "form-basic-username", "name2",
+                                           "form-basic-password", "pass2");
+});
+
+add_task(async function test_simpleNoDupesUpgradeActionOnly() {
+  await prepareLoginsAndProcessForm("https://example.com" + CROSS_ORIGIN_SECURE_PATH, [
+    new nsLoginInfo("https://example.com", "http://example.org", null,
+                    "name2", "pass2", "uname", "pword"),
+  ]);
+
+  await checkLoginFormInFrame(win, "form-basic-username", "name2",
+                                           "form-basic-password", "pass2");
+});
+
+add_task(async function test_dedupe() {
+  await prepareLoginsAndProcessForm("https://example.com" + MISSING_ACTION_PATH, [
+    new nsLoginInfo("https://example.com", "https://example.com", null,
+                    "name1", "passHTTPStoHTTPS", "uname", "pword"),
+    new nsLoginInfo("http://example.com", "http://example.com", null,
+                    "name1", "passHTTPtoHTTP", "uname", "pword"),
+    new nsLoginInfo("http://example.com", "https://example.com", null,
+                    "name1", "passHTTPtoHTTPS", "uname", "pword"),
+    new nsLoginInfo("https://example.com", "http://example.com", null,
+                    "name1", "passHTTPStoHTTP", "uname", "pword"),
+  ]);
+
+  await checkLoginFormInFrame(win, "form-basic-username", "name1",
+                                           "form-basic-password", "passHTTPStoHTTPS");
+});
+
+add_task(async function test_dedupe_subdomain() {
+  // subdomain match (should be autofilled)
+  let loginToFill = new nsLoginInfo("http://test1.example.com", "http://test1.example.com", null,
+                                    "name1", "pass1");
+  const loginToFillGUID = "subdomain-match"
+  // Assign a GUID to this login so we can ensure this is the login that gets
+  // filled later.
+  loginToFill.QueryInterface(SpecialPowers.Ci.nsILoginMetaInfo).guid = loginToFillGUID;
+
+  await prepareLoginsAndProcessForm("https://test1.example.com" + MISSING_ACTION_PATH, [
+    // All logins have the same username and password:
+    // https: (scheme match)
+    new nsLoginInfo("https://example.com", "https://example.com", null,
+                    "name1", "pass1"),
+    loginToFill,
+    // formActionOrigin match
+    new nsLoginInfo("http://example.com", "https://test1.example.com", null,
+                    "name1", "pass1"),
+  ]);
+
+  await checkLoginFormInFrame(win, "form-basic-username", "name1",
+                                   "form-basic-password", "pass1");
+
+  let filledGUID = await SpecialPowers.spawn(win, [], function getFilledGUID() {
+    let LMC = this.content.windowGlobalChild.getActor("LoginManager");
+    let doc = this.content.document;
+    let form = doc.getElementById("form-basic");
+    let { login: filledLogin } = LMC.stateForDocument(doc).fillsByRootElement.get(form);
+    return filledLogin && filledLogin.guid;
+  });
+  is(filledGUID, loginToFillGUID, "Check the correct login was filled");
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_password-only.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_password-only.html
new file mode 100644
index 0000000000..47f53bb65b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_password-only.html
@@ -0,0 +1,133 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test password-only forms should prefer a password-only login when present</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: Bug 444968
+<script>
+runChecksAfterCommonInit(null);
+
+SimpleTest.waitForExplicitFinish();
+
+const chromeScript = runInParent(async function chromeSetup() {
+  const login1A = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+  const login1B = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+  const login2A = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+  const login2B = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+  const login2C = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+
+  login1A.init("http://mochi.test:8888", "http://bug444968-1", null, "testuser1A", "testpass1A", "", "");
+  login1B.init("http://mochi.test:8888", "http://bug444968-1", null, "", "testpass1B", "", "");
+
+  login2A.init("http://mochi.test:8888", "http://bug444968-2", null, "testuser2A", "testpass2A", "", "");
+  login2B.init("http://mochi.test:8888", "http://bug444968-2", null, "", "testpass2B", "", "");
+  login2C.init("http://mochi.test:8888", "http://bug444968-2", null, "testuser2C", "testpass2C", "", "");
+
+  await Services.logins.addLogins([
+    login1A,
+    login1B,
+    login2A,
+    login2B,
+    login2C,
+  ]);
+
+  addMessageListener("removeLogins", function removeLogins() {
+    Services.logins.removeLogin(login1A);
+    Services.logins.removeLogin(login1B);
+    Services.logins.removeLogin(login2A);
+    Services.logins.removeLogin(login2B);
+    Services.logins.removeLogin(login2C);
+  });
+});
+
+SimpleTest.registerCleanupFunction(() => chromeScript.sendAsyncMessage("removeLogins"));
+</script>
+
+<p id="display"></p>
+<div id="content" style="display: none">
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+const DEFAULT_ORIGIN = window.location.origin;
+
+/* Test for Login Manager: 444968 (password-only forms should prefer a
+ * password-only login when present )
+ */
+async function startTest() {
+  const win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <!-- first 3 forms have matching user+pass and pass-only logins -->
+
+    <!-- user+pass form. -->
+    <form id="form1" action="http://bug444968-1">
+      <input  type="text"     name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <!-- password-only form. -->
+    <form id="form2" action="http://bug444968-1">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <!-- user+pass form, username prefilled -->
+    <form id="form3" action="http://bug444968-1">
+      <input  type="text"     name="uname" value="testuser1A">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+
+    <!-- next 4 forms have matching user+pass (2x) and pass-only (1x) logins -->
+
+    <!-- user+pass form. -->
+    <form id="form4" action="http://bug444968-2">
+      <input  type="text"     name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <!-- password-only form. -->
+    <form id="form5" action="http://bug444968-2">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <!-- user+pass form, username prefilled -->
+    <form id="form6" action="http://bug444968-2">
+      <input  type="text"     name="uname" value="testuser2A">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <!-- user+pass form, username prefilled -->
+    <form id="form7" action="http://bug444968-2">
+      <input  type="text"     name="uname" value="testuser2C">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>`, win, 7);
+
+  await checkLoginFormInFrameWithElementValues(win, 1, "testuser1A", "testpass1A");
+  await checkLoginFormInFrameWithElementValues(win, 2, "testpass1B");
+  await checkLoginFormInFrameWithElementValues(win, 3, "testuser1A", "testpass1A");
+
+  checkUnmodifiedFormInFrame(win, 4); // 2 logins match
+  await checkLoginFormInFrameWithElementValues(win, 5, "testpass2B");
+  await checkLoginFormInFrameWithElementValues(win, 6, "testuser2A", "testpass2A");
+  await checkLoginFormInFrameWithElementValues(win, 7, "testuser2C", "testpass2C");
+
+  SimpleTest.finish();
+}
+
+registerRunTests(0, startTest);
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_sandboxed.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_sandboxed.html
new file mode 100644
index 0000000000..ef4dfdb417
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_sandboxed.html
@@ -0,0 +1,100 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test form field autofill in sandboxed documents (null principal)</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<div id="content">
+  <iframe id="sandboxed"
+          sandbox=""></iframe>
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+const { TestUtils } = SpecialPowers.ChromeUtils.importESModule(
+  "resource://testing-common/TestUtils.sys.mjs"
+);
+
+/** Test for Login Manager: form field autofill in sandboxed documents (null principal) **/
+
+const sandboxed = document.getElementById("sandboxed");
+let uname;
+let pword;
+
+add_setup(async () => {
+  await setStoredLoginsAsync(["https://example.com", "", null, "tempuser1", "temppass1", "uname", "pword"]);
+});
+
+add_task(async function test_no_autofill_in_form() {
+  sandboxed.src = "form_basic.html";
+  const frameWindow = SpecialPowers.wrap(sandboxed).contentWindow;
+  const DOMFormHasPasswordPromise = new Promise(resolve => {
+    SpecialPowers.addChromeEventListener("DOMFormHasPassword", function onDFHP() {
+      SpecialPowers.removeChromeEventListener("DOMFormHasPassword", onDFHP);
+      resolve();
+    });
+  });
+  // Can't use SimpleTest.promiseFocus as it doesn't work with the sandbox.
+  await SimpleTest.promiseWaitForCondition(() => {
+    return frameWindow.document.readyState == "complete" &&
+             frameWindow.location.href.endsWith("form_basic.html");
+  }, "Check frame is loaded");
+  info("frame loaded");
+  await DOMFormHasPasswordPromise;
+  const frameDoc = SpecialPowers.wrap(sandboxed).contentDocument;
+
+  uname = frameDoc.getElementById("form-basic-username");
+  pword = frameDoc.getElementById("form-basic-password");
+
+  // Autofill shouldn't happen in the sandboxed frame but would have happened by
+  // now since DOMFormHasPassword was observed above.
+  await ensureLoginFormStaysFilledWith(uname, "", pword, "");
+
+  info("blurring the username field after typing the username");
+  uname.focus();
+  uname.setUserInput("tempuser1");
+  synthesizeKey("VK_TAB", {}, frameWindow);
+
+  await TestUtils.waitForCondition(() => {
+    return uname.value === "tempuser1" & pword.value === "";
+  }, "Username and password field should be filled");
+});
+
+add_task(async function test_no_autofill_outside_form() {
+  sandboxed.src = "formless_basic.html";
+  const frameWindow = SpecialPowers.wrap(sandboxed).contentWindow;
+  const DOMInputPasswordAddedPromise = new Promise(resolve => {
+    SpecialPowers.addChromeEventListener("DOMInputPasswordAdded", function onDIPA() {
+      SpecialPowers.removeChromeEventListener("DOMInputPasswordAdded", onDIPA);
+      resolve();
+    });
+  });
+  // Can't use SimpleTest.promiseFocus as it doesn't work with the sandbox.
+  await SimpleTest.promiseWaitForCondition(() => {
+    return frameWindow.document.readyState == "complete" &&
+             frameWindow.location.href.endsWith("formless_basic.html");
+  }, "Check frame is loaded");
+  info("frame loaded");
+  await DOMInputPasswordAddedPromise;
+  const frameDoc = SpecialPowers.wrap(sandboxed).contentDocument;
+
+  uname = frameDoc.getElementById("form-basic-username");
+  pword = frameDoc.getElementById("form-basic-password");
+
+  // Autofill shouldn't happen in the sandboxed frame but would have happened by
+  // now since DOMInputPasswordAdded was observed above.
+  await ensureLoginFormStaysFilledWith(uname, "", pword, "");
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_tab_between_fields.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_tab_between_fields.html
new file mode 100644
index 0000000000..c88a6713f4
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_tab_between_fields.html
@@ -0,0 +1,151 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autocomplete behavior when tabbing between form fields</title>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script>
+let nsLoginInfo = SpecialPowers.wrap(SpecialPowers.Components).Constructor("@mozilla.org/login-manager/loginInfo;1",
+                                                                           SpecialPowers.Ci.nsILoginInfo,
+                                                                           "init");
+let readyPromise = registerRunTests();
+</script>
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+let DEFAULT_ORIGIN = window.location.origin;
+let win;
+let html = `
+  <form id="form1" action="https://autofill" onsubmit="return false;">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+    <button type="submit">Submit</button>
+  </form>`;
+
+async function prepareLogins(logins = []) {
+  await LoginManager.removeAllUserFacingLogins();
+
+  for (let login of logins) {
+    await LoginManager.addLoginAsync(login);
+  }
+  let count = (await LoginManager.getAllLogins()).length;
+  is(count, logins.length, "All logins were added");
+}
+
+const availableLogins = {
+  "exampleUser1": new nsLoginInfo(DEFAULT_ORIGIN, "https://autofill", null,
+                              "user1", "pass1", "uname", "pword"),
+}
+
+async function recreateTreeInWindow(formNum) {
+  await SpecialPowers.spawn(win, [formNum], (formNumF) => {
+    let form = this.content.document.querySelector(`#form${formNumF}`);
+    // eslint-disable-next-line no-self-assign
+    form.outerHTML = form.outerHTML;
+  });
+}
+
+const tests = [
+  {
+    name: "autofill_disabled_exact_username",
+    autofillEnabled: false,
+    logins: ["exampleUser1"],
+    expectedAutofillUsername: "",
+    expectedAutofillPassword: "",
+    typeUsername: "user1",
+    expectedTabbedUsername: "user1",
+    expectedTabbedPassword: "",
+  },
+  {
+    name: "autofill_enabled_exact_username",
+    autofillEnabled: true,
+    logins: ["exampleUser1"],
+    expectedAutofillUsername: "user1",
+    expectedAutofillPassword: "pass1",
+    typeUsername: "user1",
+    expectedTabbedUsername: "user1",
+    expectedTabbedPassword: "pass1",
+  },
+];
+
+add_setup(async () => {
+  ok(readyPromise, "check promise is available");
+  await readyPromise;
+  win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, html, win);
+});
+
+async function testResultOfTabInteractions(testData) {
+  await SpecialPowers.pushPrefEnv({"set": [
+    ["signon.autofillForms", testData.autofillEnabled],
+  ]});
+
+  await SimpleTest.promiseFocus(win);
+  let logins = testData.logins.map(name => availableLogins[name]);
+  await prepareLogins(logins);
+
+  info("recreating form");
+  let processed = promiseFormsProcessed();
+  await recreateTreeInWindow(1);
+  info("waiting for form processed");
+  await processed;
+  // check autofill results
+  await checkLoginFormInFrameWithElementValues(win, 1, testData.expectedAutofillUsername, testData.expectedAutofillPassword);
+
+  await SpecialPowers.spawn(win, [testData.typeUsername], async (typeUsername) => {
+    let doc = this.content.document;
+    let pword = doc.querySelector("[name='pword']");
+    let uname = doc.querySelector("[name='uname']");
+
+    pword.setUserInput("");
+    uname.setUserInput("");
+
+    info("Placing focus in the username field");
+    uname.focus();
+
+    if (typeUsername) {
+      info("Filling username field");
+      EventUtils.sendString(typeUsername, this.content);
+    }
+
+    EventUtils.synthesizeKey("KEY_Tab", {}, this.content); // blur un, focus pw
+    await new Promise(resolve => SpecialPowers.executeSoon(resolve));
+
+    ok(pword.matches("input:focus"), "pword field is focused");
+  });
+
+  await checkLoginFormInFrameWithElementValues(win, 1, testData.expectedTabbedUsername, testData.expectedTabbedPassword);
+
+  await recreateTreeInWindow(1);
+  await promiseFormsProcessed();
+
+  await SpecialPowers.spawn(win, [], () => {
+    EventUtils.synthesizeKey("KEY_Escape", {}, this.content);
+  });
+}
+
+for (let testData of tests) {
+  let tmp = {
+    async [testData.name]() {
+      await testResultOfTabInteractions(testData);
+    },
+  };
+  add_task(tmp[testData.name]);
+}
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_username-only.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_username-only.html
new file mode 100644
index 0000000000..860c317409
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_username-only.html
@@ -0,0 +1,107 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofill on username-form</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Test autofill on username-form
+
+<script>
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [window.location.origin, "https://autofill", null, "user1", "pass1"]
+  );
+});
+
+add_task(async function test_autofill_username_only_form() {
+  await loadRecipes({
+    siteRecipes: [{
+      hosts: ["mochi.test:8888"],
+      notUsernameSelector: "input[name='shouldnotfill']",
+    }],
+  });
+
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+
+  // 5 out of the 7 forms should be autofilled
+  await loadFormIntoWindow(window.location.origin, `
+    <!-- no password field, 1 username field -->
+    <form id='form1' action='https://autofill'> 1
+        <input type='text' name='uname' autocomplete='username' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- no password field, 1 username field, with a value set -->
+    <form id='form2' action='https://autofill'> 2
+        <input type='text' name='uname' autocomplete='username' value='someuser'>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- no password field, 2 username fields, should be ignored -->
+    <form id='form3' action='https://autofill'> 3
+        <input type='text' name='uname1' autocomplete='username' value=''>
+        <input type='text' name='uname2' autocomplete='username' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- no password field, 1 username field, too small for the username login -->
+    <form id='form4' action='https://autofill'> 4
+        <input type='text' name='uname' value='' maxlength="4" autocomplete='username'>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- no password field, 1 username field, too small for the username login -->
+    <form id='form5' action='https://autofill'> 5
+        <input type='text' name='uname' value='' maxlength="0" autocomplete='username'>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- no password field, 1 text input field (not a username-only form), should be ignored -->
+    <form id='form6' action='https://autofill'> 6
+        <input type='text' name='uname' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- no password field, 1 username field that matches notUsernameSelector recipe -->
+    <form id='form7' action='https://autofill'> 7
+        <input type='text' name='shouldnotfill' autocomplete='username' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>`, win, 5);
+
+  await checkLoginFormInFrameWithElementValues(win, 1, "user1");
+  await checkLoginFormInFrameWithElementValues(win, 2, "someuser");
+  await checkUnmodifiedFormInFrame(win, 3);
+  await checkUnmodifiedFormInFrame(win, 4);
+  await checkUnmodifiedFormInFrame(win, 5);
+  await checkUnmodifiedFormInFrame(win, 6);
+  await checkUnmodifiedFormInFrame(win, 7);
+
+  await resetRecipes();
+});
+</script>
+
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test"></pre>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofill_username-only_threshold.html b/toolkit/components/passwordmgr/test/mochitest/test_autofill_username-only_threshold.html
new file mode 100644
index 0000000000..d9a2e08095
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofill_username-only_threshold.html
@@ -0,0 +1,83 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofill on username-form when the number of form exceeds the lookup threshold</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Test not autofill on username-form when the number of form exceeds the lookup threshold
+
+<script>
+add_setup(async () => {
+  await SpecialPowers.pushPrefEnv({"set": [["signon.usernameOnlyForm.lookupThreshold", 5]]});
+
+  await setStoredLoginsAsync(
+    [window.location.origin, "https://autofill", null, "user1", "pass1"]
+  );
+});
+
+add_task(async function test_autofill_username_only_form() {
+  const win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+
+  await loadFormIntoWindow(window.location.origin, `
+    <!-- no password field, 1 username field -->
+    <form id='form1' action='https://autofill'> 1
+        <input type='text' name='uname' autocomplete='username' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <form id='form2' action='https://autofill'> 2
+        <input type='text' name='uname' autocomplete='username' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <form id='form3' action='https://autofill'> 3
+        <input type='text' name='uname' autocomplete='username' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <form id='form4' action='https://autofill'> 4
+        <input type='text' name='uname' autocomplete='username' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <form id='form5' action='https://autofill'> 5
+        <input type='text' name='uname' autocomplete='username' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <form id='form6' action='https://autofill'> 6
+        <input type='text' name='uname' autocomplete='username' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>`, win, 5);
+
+  await checkLoginFormInFrameWithElementValues(win, 1, "user1");
+  await checkLoginFormInFrameWithElementValues(win, 2, "user1");
+  await checkLoginFormInFrameWithElementValues(win, 3, "user1");
+  await checkLoginFormInFrameWithElementValues(win, 4, "user1");
+  await checkLoginFormInFrameWithElementValues(win, 5, "user1");
+  await checkUnmodifiedFormInFrame(win, 6);
+});
+</script>
+
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_autofocus_js.html b/toolkit/components/passwordmgr/test/mochitest/test_autofocus_js.html
new file mode 100644
index 0000000000..803197c2a2
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_autofocus_js.html
@@ -0,0 +1,114 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test login autocomplete is activated when focused by js on load</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<div id="content">
+  <iframe></iframe>
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+const iframe = document.getElementsByTagName("iframe")[0];
+let iframeDoc, hostname;
+
+add_setup(async () => {
+  const origin = window.location.origin;
+  await setStoredLoginsAsync(
+    [origin, origin, null, "name", "pass"],
+    [origin, origin, null, "name1", "pass1"]
+  );
+
+  const processedPromise = promiseFormsProcessed();
+  iframe.src = "/tests/toolkit/components/passwordmgr/test/mochitest/form_autofocus_js.html";
+  await new Promise(resolve => {
+    iframe.addEventListener("load", function() {
+      resolve();
+    }, {once: true});
+  });
+
+  await processedPromise;
+
+  hostname = await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    return this.content.document.documentURIObject.host;
+  });
+
+  SimpleTest.requestFlakyTimeout("Giving a chance for the unexpected popupshown to occur");
+});
+
+add_task(async function test_initial_focus() {
+  let results = await notifyMenuChanged(3, "name");
+  checkAutoCompleteResults(results, ["name", "name1"], hostname, "Two login results");
+  synthesizeKey("KEY_ArrowDown");
+  synthesizeKey("KEY_Enter");
+  await promiseFormsProcessedInSameProcess();
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    Assert.equal(this.content.document.getElementById("form-basic-password").value, "pass", "Check first password filled");
+  });
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is now closed");
+});
+
+// This depends on the filling from the previous test.
+add_task(async function test_not_reopened_if_filled() {
+  listenForUnexpectedPopupShown();
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    this.content.document.getElementById("form-basic-username").focus();
+  });
+  info("Waiting to see if a popupshown occurs");
+  await new Promise(resolve => setTimeout(resolve, 1000));
+
+  // cleanup
+  gPopupShownExpected = true;
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    this.content.document.getElementById("form-basic-submit").focus();
+  });
+});
+
+add_task(async function test_reopened_after_edit_not_matching_saved() {
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    this.content.document.getElementById("form-basic-username").value = "nam";
+  });
+  await popupBy(async () => {
+    await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+      this.content.document.getElementById("form-basic-username").focus();
+    });
+  });
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    this.content.document.getElementById("form-basic-submit").focus();
+  });
+});
+
+add_task(async function test_not_reopened_after_selecting() {
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    this.content.document.getElementById("form-basic-username").value = "";
+    this.content.document.getElementById("form-basic-password").value = "";
+  });
+  listenForUnexpectedPopupShown();
+
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    let formFillController = SpecialPowers.getFormFillController();
+    let usernameField = this.content.document.getElementById("form-basic-username");
+    formFillController.markAsLoginManagerField(usernameField);
+  });
+
+  info("Waiting to see if a popupshown occurs");
+  await new Promise(resolve => setTimeout(resolve, 1000));
+
+  // Cleanup
+  gPopupShownExpected = true;
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form.html
new file mode 100644
index 0000000000..d13fd1369f
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form.html
@@ -0,0 +1,48 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test basic autofill</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: simple form fill
+
+<script>
+gTestDependsOnDeprecatedLogin = true;
+runChecksAfterCommonInit(startTest);
+
+let DEFAULT_ORIGIN = window.location.origin;
+
+/** Test for Login Manager: form fill, multiple forms. **/
+
+async function startTest() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <form id="form1" action="formtest.js">
+      <p>This is form 1.</p>
+      <input id="username-1" type="text"       name="uname">
+      <input id="password-1" type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>`, win);
+  await checkLoginFormInFrame(win, "username-1", "testuser", "password-1", "testpass");
+
+  SimpleTest.finish();
+}
+</script>
+
+<p id="display"></p>
+
+<div id="content" style="display: none">
+
+
+</div>
+
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_0pw.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_0pw.html
new file mode 100644
index 0000000000..64450300d6
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_0pw.html
@@ -0,0 +1,70 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test forms with no password fields</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: forms with no password fields
+<p id="display"></p>
+
+<div id="content" style="display: none">
+
+  <!-- Form with no user field or password field -->
+  <form id="form1" action="formtest.js">
+    <button type="submit">Submit</button>
+    <button type="reset"> Reset </button>
+  </form>
+
+  <!-- Form with no user field or password field, but one other field -->
+  <form id="form2" action="formtest.js">
+    <input  type="checkbox">
+    <button type="submit">Submit</button>
+    <button type="reset"> Reset </button>
+  </form>
+
+  <!-- Form with no user field or password field, but one other field -->
+  <form id="form3" action="formtest.js">
+    <input  type="checkbox" name="uname" value="">
+    <button type="submit">Submit</button>
+    <button type="reset"> Reset </button>
+  </form>
+
+  <!-- Form with a text field, but no password field -->
+  <form id="form4" action="formtest.js">
+    <input  type="text"       name="yyyyy">
+
+    <button type="submit">Submit</button>
+    <button type="reset"> Reset </button>
+  </form>
+
+  <!-- Form with a user field, but no password field -->
+  <form id="form5" action="formtest.js">
+    <input  type="text"       name="uname">
+
+    <button type="submit">Submit</button>
+    <button type="reset"> Reset </button>
+  </form>
+
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+function startTest() {
+  is(getFormElementByName(3, "uname").value, "", "Checking for unfilled checkbox (form 3)");
+  is(getFormElementByName(4, "yyyyy").value, "", "Checking for unfilled text field (form 4)");
+  is(getFormElementByName(5, "uname").value, "", "Checking for unfilled text field (form 5)");
+
+  SimpleTest.finish();
+}
+
+runChecksAfterCommonInit(startTest);
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_1pw.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_1pw.html
new file mode 100644
index 0000000000..bb91d9cf3e
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_1pw.html
@@ -0,0 +1,171 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofill for forms with 1 password field</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: forms with 1 password field
+<script>
+gTestDependsOnDeprecatedLogin = true;
+runChecksAfterCommonInit(() => startTest());
+
+let DEFAULT_ORIGIN = window.location.origin;
+</script>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: simple form fill **/
+
+async function startTest() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <!-- no username fields -->
+
+    <form id='form1' action='formtest.js'> 1
+        <!-- Blank, so fill in the password -->
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form2' action='formtest.js'> 2
+        <!-- Already contains the password, so nothing to do. -->
+        <input type='password' name='pname' value='testpass'>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form3' action='formtest.js'> 3
+        <!-- Contains unknown password, so don't change it -->
+        <input type='password' name='pname' value='xxxxxxxx'>
+        <button type='submit'>Submit</button>
+    </form>
+
+
+    <!-- username fields -->
+
+    <form id='form4' action='formtest.js'> 4
+        <!-- Blanks, so fill in login -->
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form5' action='formtest.js'> 5
+        <!-- Username already set, so fill in password -->
+        <input type='text'     name='uname' value='testuser'>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form6' action='formtest.js'> 6
+        <!-- Unknown username, so don't fill in password -->
+        <input type='text'     name='uname' value='xxxxxxxx'>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form7' action='formtest.js'> 7
+        <!-- Password already set, could fill in username but that's weird so we don't -->
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value='testpass'>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form8' action='formtest.js'> 8
+        <!-- Unknown password, so don't fill in a username -->
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value='xxxxxxxx'>
+        <button type='submit'>Submit</button>
+    </form>
+
+
+
+    <!-- extra text fields -->
+
+    <form id='form9' action='formtest.js'> 9
+        <!-- text field _after_ password should never be treated as a username field -->
+        <input type='password' name='pname' value=''>
+        <input type='text'     name='uname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form10' action='formtest.js'> 10
+        <!-- only the first text field before the password should be for username -->
+        <input type='text'     name='other' value=''>
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form11' action='formtest.js'> 11
+        <!-- variation just to make sure extra text field is still ignored -->
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value=''>
+        <input type='text'     name='other' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+
+
+    <!-- same as last bunch, but with xxxx in the extra field. -->
+
+    <form id='form12' action='formtest.js'> 12
+        <!-- text field _after_ password should never be treated as a username field -->
+        <input type='password' name='pname' value=''>
+        <input type='text'     name='uname' value='xxxxxxxx'>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form13' action='formtest.js'> 13
+        <!-- only the first text field before the password should be for username -->
+        <input type='text'     name='other' value='xxxxxxxx'>
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form14' action='formtest.js'> 14
+        <!-- variation just to make sure extra text field is still ignored -->
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value=''>
+        <input type='text'     name='other' value='xxxxxxxx'>
+        <button type='submit'>Submit</button>
+    </form>`, win, 14);
+
+  var f = 1;
+
+  // 1-3
+  await checkLoginFormInFrameWithElementValues(win, f++, "testpass");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testpass");
+  await checkLoginFormInFrameWithElementValues(win, f++, "xxxxxxxx");
+
+  // 4-8
+  await checkLoginFormInFrameWithElementValues(win, f++, "testuser", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testuser", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, f++, "xxxxxxxx", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, f++, "", "xxxxxxxx");
+
+  // 9-14
+  await checkLoginFormInFrameWithElementValues(win, f++, "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "", "testuser", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testuser", "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testpass", "xxxxxxxx");
+  await checkLoginFormInFrameWithElementValues(win, f++, "xxxxxxxx", "testuser", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testuser", "testpass", "xxxxxxxx");
+
+  SimpleTest.finish();
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_1pw_2.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_1pw_2.html
new file mode 100644
index 0000000000..d7aaadc895
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_1pw_2.html
@@ -0,0 +1,115 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test forms with 1 password field, part 2</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: forms with 1 password field, part 2
+<script>
+gTestDependsOnDeprecatedLogin = true;
+runChecksAfterCommonInit(() => startTest());
+
+let DEFAULT_ORIGIN = window.location.origin;
+</script>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: simple form fill, part 2 **/
+
+async function startTest() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <form id='form1' action='formtest.js'> 1
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form2' action='formtest.js'> 2
+        <input type='password' name='pname' value='' disabled>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form3' action='formtest.js'> 3
+        <input type='password' name='pname' value='' readonly>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form4' action='formtest.js'> 4
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form5' action='formtest.js'> 5
+        <input type='text'     name='uname' value='' disabled>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form6' action='formtest.js'> 6
+        <input type='text'     name='uname' value='' readonly>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form7' action='formtest.js'> 7
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value='' disabled>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form8' action='formtest.js'> 8
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value='' readonly>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form9' action='formtest.js'> 9
+        <input type='text'     name='uname' value='TESTUSER'>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form10' action='formtest.js'> 10
+        <input type='text'     name='uname' value='TESTUSER' readonly>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form11' action='formtest.js'> 11
+        <input type='text'     name='uname' value='TESTUSER' disabled>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>`, win, 11);
+
+  var f;
+
+  // Test various combinations of disabled/readonly inputs
+  await checkLoginFormInFrameWithElementValues(win, 1, "testpass"); // control
+  await checkUnmodifiedFormInFrame(win, 2);
+  await checkUnmodifiedFormInFrame(win, 3);
+  await checkLoginFormInFrameWithElementValues(win, 4, "testuser", "testpass"); // control
+  for (f = 5; f <= 8; f++) {
+    await checkUnmodifiedFormInFrame(win, f);
+  }
+  // Test case-insensitive comparison of username field
+  await checkLoginFormInFrameWithElementValues(win, 9, "testuser", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, 10, "TESTUSER", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, 11, "TESTUSER", "testpass");
+
+  SimpleTest.finish();
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_2pw_1.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_2pw_1.html
new file mode 100644
index 0000000000..1d9224a819
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_2pw_1.html
@@ -0,0 +1,190 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofill for forms with 2 password fields</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: forms with 2 password fields
+<script>
+gTestDependsOnDeprecatedLogin = true;
+runChecksAfterCommonInit(() => startTest());
+
+let DEFAULT_ORIGIN = window.location.origin;
+</script>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: simple form fill **/
+
+async function startTest() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <!-- no username fields -->
+
+    <form id='form1' action='formtest.js'> 1
+        <!-- simple form, fill in first pw -->
+        <input type='password' name='pname' value=''>
+        <input type='password' name='qname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form2' action='formtest.js'> 2
+        <!-- same but reverse pname and qname, field names are ignored. -->
+        <input type='password' name='qname' value=''>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form3' action='formtest.js'> 3
+        <!-- text field after password fields should be ignored, no username. -->
+        <input type='password' name='pname' value=''>
+        <input type='password' name='qname' value=''>
+        <input type='text'     name='uname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form4' action='formtest.js'> 4
+        <!-- nothing to do, password already present -->
+        <input type='password' name='pname' value='testpass'>
+        <input type='password' name='qname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form5' action='formtest.js'> 5
+        <!-- don't clobber an existing unrecognized password -->
+        <input type='password' name='pname' value='xxxxxxxx'>
+        <input type='password' name='qname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form6' action='formtest.js'> 6
+        <!-- fill in first field, 2nd field shouldn't be touched anyway. -->
+        <input type='password' name='pname' value=''>
+        <input type='password' name='qname' value='xxxxxxxx'>
+        <button type='submit'>Submit</button>
+    </form>
+
+
+
+    <!-- with username fields -->
+
+
+
+    <form id='form7' action='formtest.js'> 7
+        <!-- simple form, should fill in username and first pw -->
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value=''>
+        <input type='password' name='qname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form8' action='formtest.js'> 8
+        <!-- reverse pname and qname, field names are ignored. -->
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='qname' value=''>
+        <input type='password' name='pname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form9' action='formtest.js'> 9
+        <!-- username already filled, so just fill first password -->
+        <input type='text'     name='uname' value='testuser'>
+        <input type='password' name='pname' value=''>
+        <input type='password' name='qname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form10' action='formtest.js'> 10
+        <!-- unknown username, don't fill in a password -->
+        <input type='text'     name='uname' value='xxxxxxxx'>
+        <input type='password' name='pname' value=''>
+        <input type='password' name='qname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form11' action='formtest.js'> 11
+        <!-- don't clobber unknown password -->
+        <input type='text'     name='uname' value='testuser'>
+        <input type='password' name='pname' value='xxxxxxxx'>
+        <input type='password' name='qname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form12' action='formtest.js'> 12
+        <!-- fill in 1st pass, don't clobber 2nd pass -->
+        <input type='text'     name='uname' value='testuser'>
+        <input type='password' name='pname' value=''>
+        <input type='password' name='qname' value='xxxxxxxx'>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form13' action='formtest.js'> 13
+        <!-- nothing to do, user and pass prefilled. life is easy. -->
+        <input type='text'     name='uname' value='testuser'>
+        <input type='password' name='pname' value='testpass'>
+        <input type='password' name='qname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form14' action='formtest.js'> 14
+        <!-- shouldn't fill in username because 1st pw field is unknown. -->
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value='xxxxxxxx'>
+        <input type='password' name='qname' value='testpass'>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form15' action='formtest.js'> 15
+        <!-- textfield in the middle of pw fields should be ignored -->
+        <input type='password' name='pname' value=''>
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='qname' value=''>
+        <button type='submit'>Submit</button>
+    </form>
+
+    <form id='form16' action='formtest.js'> 16
+        <!-- same, and don't clobber existing unknown password -->
+        <input type='password' name='pname' value='xxxxxxxx'>
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='qname' value=''>
+        <button type='submit'>Submit</button>
+    </form>`, win, 16);
+
+  var f = 1;
+
+  // 1-6 no username
+  await checkLoginFormInFrameWithElementValues(win, f++, "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testpass", "", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "xxxxxxxx", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testpass", "xxxxxxxx");
+
+  // 7-15 with username
+  await checkLoginFormInFrameWithElementValues(win, f++, "testuser", "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testuser", "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testuser", "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "xxxxxxxx", "", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testuser", "xxxxxxxx", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testuser", "testpass", "xxxxxxxx");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testuser", "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "", "xxxxxxxx", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, f++, "testpass", "", "");
+  await checkLoginFormInFrameWithElementValues(win, f++, "xxxxxxxx", "", "");
+
+  SimpleTest.finish();
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_2pw_2.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_2pw_2.html
new file mode 100644
index 0000000000..a2c60e5964
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_2pw_2.html
@@ -0,0 +1,111 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for form fill with 2 password fields</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: form fill, 2 password fields
+<p id="display"></p>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: form fill, 2 password fields **/
+
+/*
+ * If a form has two password fields, other things may be going on....
+ *
+ * 1 - The user might be creating a new login (2nd field for typo checking)
+ * 2 - The user is changing a password (old and new password each have field)
+ *
+ * This test is for case #1.
+ */
+
+var numSubmittedForms = 0;
+var numStartingLogins = 0;
+
+function startTest() {
+  // Check for unfilled forms
+  is(getFormElementByName(1, "uname").value, "", "Checking username 1");
+  is(getFormElementByName(1, "pword").value, "", "Checking password 1A");
+  is(getFormElementByName(1, "qword").value, "", "Checking password 1B");
+
+  // Fill in the username and password fields, for account creation.
+  // Form 1
+  SpecialPowers.wrap(getFormElementByName(1, "uname")).setUserInput("newuser1");
+  SpecialPowers.wrap(getFormElementByName(1, "pword")).setUserInput("newpass1");
+  SpecialPowers.wrap(getFormElementByName(1, "qword")).setUserInput("newpass1");
+
+  // eslint-disable-next-line no-unused-vars
+  var button = getFormSubmitButton(1);
+
+  todo(false, "form submission disabled, can't auto-accept dialog yet");
+  SimpleTest.finish();
+}
+
+
+// Called by each form's onsubmit handler.
+function checkSubmit(formNum) {
+  numSubmittedForms++;
+
+  // End the test at the last form.
+  if (formNum == 999) {
+    is(numSubmittedForms, 999, "Ensuring all forms submitted for testing.");
+
+    (async () => {
+      var numEndingLogins = await LoginManager.countLogins("", "", "");
+
+      ok(numEndingLogins > 0, "counting logins at end");
+      is(numStartingLogins, numEndingLogins + 222, "counting logins at end");
+
+      SimpleTest.finish();
+    })();
+    return false; // return false to cancel current form submission
+  }
+
+  // submit the next form.
+  var button = getFormSubmitButton(formNum + 1);
+  button.click();
+
+  return false; // return false to cancel current form submission
+}
+
+
+function getFormSubmitButton(formNum) {
+  var form = $("form" + formNum); // by id, not name
+  ok(form != null, "getting form " + formNum);
+
+  // we can't just call form.submit(), because that doesn't seem to
+  // invoke the form onsubmit handler.
+  var button = form.firstChild;
+  while (button && button.type != "submit") {
+    button = button.nextSibling;
+  }
+  ok(button != null, "getting form submit button");
+
+  return button;
+}
+
+runChecksAfterCommonInit(startTest);
+
+</script>
+</pre>
+<div id="content" style="display: none">
+  <form id="form1" onsubmit="return checkSubmit(1)" action="http://newuser.com">
+    <input  type="text"     name="uname">
+    <input  type="password" name="pword">
+    <input  type="password" name="qword">
+
+    <button type="submit">Submit</button>
+    <button type="reset"> Reset </button>
+  </form>
+
+</div>
+
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_3pw_1.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_3pw_1.html
new file mode 100644
index 0000000000..59aec20612
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_3pw_1.html
@@ -0,0 +1,259 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofill for forms with 3 password fields</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: forms with 3 password fields (form filling)
+<script>
+gTestDependsOnDeprecatedLogin = true;
+runChecksAfterCommonInit(() => startTest());
+
+let DEFAULT_ORIGIN = window.location.origin;
+</script>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: form fill, 3 password fields **/
+
+// Test to make sure 3-password forms are filled properly.
+
+async function startTest() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <p>The next three forms are <b>user/pass/passB/passC</b>, as all-empty, preuser(only), and preuser/pass</p>
+    <form id="form1" action="formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+      <input  type="password"   name="qword">
+      <input  type="password"   name="rword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <form id="form2" action="formtest.js">
+      <input  type="text"       name="uname"  value="testuser">
+      <input  type="password"   name="pword">
+      <input  type="password"   name="qword">
+      <input  type="password"   name="rword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <form id="form3" action="formtest.js">
+      <input  type="text"       name="uname"  value="testuser">
+      <input  type="password"   name="pword"  value="testpass">
+      <input  type="password"   name="qword">
+      <input  type="password"   name="rword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+
+    <p>The next three forms are <b>user/passB/pass/passC</b>, as all-empty, preuser(only), and preuser/pass</p>
+    <form id="form4" action="formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="qword">
+      <input  type="password"   name="pword">
+      <input  type="password"   name="rword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <form id="form5" action="formtest.js">
+      <input  type="text"       name="uname"  value="testuser">
+      <input  type="password"   name="qword">
+      <input  type="password"   name="pword">
+      <input  type="password"   name="rword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <form id="form6" action="formtest.js">
+      <input  type="text"       name="uname"  value="testuser">
+      <input  type="password"   name="qword">
+      <input  type="password"   name="pword"  value="testpass">
+      <input  type="password"   name="rword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <p>The next three forms are <b>user/passB/passC/pass</b>, as all-empty, preuser(only), and preuser/pass</p>
+    <form id="form7" action="formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="qword">
+      <input  type="password"   name="rword">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <form id="form8" action="formtest.js">
+      <input  type="text"       name="uname"  value="testuser">
+      <input  type="password"   name="qword">
+      <input  type="password"   name="rword">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <form id="form9" action="formtest.js">
+      <input  type="text"       name="uname"  value="testuser">
+      <input  type="password"   name="qword">
+      <input  type="password"   name="rword">
+      <input  type="password"   name="pword"  value="testpass">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>`, win, 9);
+
+  let TESTCASES = [
+    // Check form 1
+    {
+      formNum: 1,
+      isAssertionTuples: [
+        ["uname", "testuser", "Checking username 1"],
+        ["pword", "testpass", "Checking password 1"],
+        ["qword", "", "Checking password 1 (q)"],
+        ["rword", "", "Checking password 1 (r)"],
+      ],
+    },
+    // Check form 2
+    {
+      formNum: 2,
+      isAssertionTuples: [
+        ["uname", "testuser", "Checking username 2"],
+        ["pword", "testpass", "Checking password 2"],
+        ["qword", "", "Checking password 2 (q)"],
+        ["rword", "", "Checking password 2 (r)"],
+      ],
+    },
+    // Check form 3
+    {
+      formNum: 3,
+      isAssertionTuples: [
+        ["uname", "testuser", "Checking username 3"],
+        ["pword", "testpass", "Checking password 3"],
+        ["qword", "", "Checking password 3 (q)"],
+        ["rword", "", "Checking password 3 (r)"],
+      ],
+    },
+    // Check form 4
+    {
+      formNum: 4,
+      isAssertionTuples: [
+        ["uname", "testuser", "Checking username 4"],
+        ["rword", "", "Checking password 4 (r)"],
+      ],
+      todoIsAssertionTuples: [
+        ["qword", "", "Checking password 4 (q)"],
+        ["pword", "testpass", "Checking password 4"],
+      ],
+    },
+    // Check form 5
+    {
+      formNum: 5,
+      isAssertionTuples: [
+        ["uname", "testuser", "Checking username 5"],
+        ["rword", "", "Checking password 5 (r)"],
+      ],
+      todoIsAssertionTuples: [
+        ["qword", "", "Checking password 5 (q)"],
+        ["pword", "testpass", "Checking password 5"],
+      ],
+    },
+    // Check form 6
+    {
+      formNum: 6,
+      isAssertionTuples: [
+        ["uname", "testuser", "Checking username 6"],
+        ["pword", "testpass", "Checking password 6"],
+        ["rword", "", "Checking password 6 (r)"],
+      ],
+      todoIsAssertionTuples: [
+        ["qword", "", "Checking password 6 (q)"],
+      ],
+    },
+    // Check form 7
+    {
+      formNum: 7,
+      isAssertionTuples: [
+        ["uname", "testuser", "Checking username 7"],
+        ["rword", "", "Checking password 7 (r)"],
+      ],
+      todoIsAssertionTuples: [
+        ["qword", "", "Checking password 7 (q)"],
+        ["pword", "testpass", "Checking password 7"],
+      ],
+    },
+    // Check form 8
+    {
+      formNum: 8,
+      isAssertionTuples: [
+        ["uname", "testuser", "Checking username 8"],
+        ["rword", "", "Checking password 8 (r)"],
+      ],
+      todoIsAssertionTuples: [
+        ["qword", "", "Checking password 8 (q)"],
+        ["pword", "testpass", "Checking password 8"],
+      ],
+    },
+    // Check form 9
+    {
+      formNum: 9,
+      isAssertionTuples: [
+        ["uname", "testuser", "Checking username 9"],
+        ["rword", "", "Checking password 9 (r)"],
+        ["pword", "testpass", "Checking password 9"],
+      ],
+      todoIsAssertionTuples: [
+        ["qword", "", "Checking password 9 (q)"],
+      ],
+    },
+  ];
+
+  await SpecialPowers.spawn(win, [TESTCASES], (testcasesF) => {
+    let doc = this.content.document;
+    for (let testcase of testcasesF) {
+      let { formNum } = testcase;
+      for (let tuple of testcase.isAssertionTuples) {
+        let [name, value, message] = tuple;
+        is(doc.querySelector(`#form${formNum} input[name=${name}]`).value, value, message);
+      }
+      if (!testcase.todoIsAssertionTuples) {
+        continue;
+      }
+      // TODO: Bug 1669614
+      // for (let tuple of testcase.todoIsAssertionTuples) {
+      //   let [name, value, message] = tuple;
+      //   todo_is(doc.querySelector(`#form${formNum} input[name=${name}]`).value, value, message);
+      // }
+    }
+  });
+
+  // TODO: as with the 2-password cases, add tests to check for creating new
+  // logins and changing passwords.
+  SimpleTest.finish();
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_honor_autocomplete_off.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_honor_autocomplete_off.html
new file mode 100644
index 0000000000..42214485c8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_honor_autocomplete_off.html
@@ -0,0 +1,149 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test login autofill autocomplete when signon.autofillForms.autocompleteOff is false</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: autofilling when autocomplete=off
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content"></div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+/** Test for Login Manager: multiple login autocomplete. **/
+
+// Check for expected username/password in form.
+function checkFormValues(form, expectedUsername, expectedPassword) {
+  let uname = form.querySelector("[name='uname']");
+  let pword = form.querySelector("[name='pword']");
+  is(uname.value, expectedUsername, `Checking ${form.id} username is: ${expectedUsername}`);
+  is(pword.value, expectedPassword, `Checking ${form.id} password is: ${expectedPassword}`);
+}
+
+async function autoCompleteFieldsFromFirstMatch(form) {
+  // trigger autocomplete from the username field
+  await SimpleTest.promiseFocus(form.ownerGlobal);
+  let uname = form.querySelector("[name='uname']");
+  await popupBy(() => uname.focus());
+
+  let formFilled = promiseFormsProcessedInSameProcess();
+  await synthesizeKey("KEY_ArrowDown"); // open
+  await synthesizeKey("KEY_Enter");
+  await formFilled;
+  await Promise.resolve();
+}
+
+add_setup(async () => {
+  // Set the pref before the document loads.
+  SpecialPowers.setBoolPref("signon.autofillForms.autocompleteOff", false);
+  SimpleTest.registerCleanupFunction(() => {
+    SpecialPowers.clearUserPref("signon.autofillForms.autocompleteOff");
+  });
+
+  await setStoredLoginsAsync(
+    [window.location.origin, "https://autocomplete", null, "singleuser", "singlepass", "uname", "pword"]
+  );
+  listenForUnexpectedPopupShown();
+});
+
+/* Tests for autofill of single-user forms for when we honor autocomplete=off on password fields */
+add_task(async function honor_password_autocomplete_off() {
+  const form = createLoginForm({
+    action: "https://autocomplete",
+    password: {
+      autocomplete: "off"
+    }
+  });
+  await promiseFormsProcessedInSameProcess();
+  await SimpleTest.promiseFocus(window);
+  // With the pref toggled off, and with autocomplete=off on the password field,
+  // we expect not to have autofilled this form
+  checkFormValues(form, "", "");
+  // ..but it should autocomplete just fine
+  await autoCompleteFieldsFromFirstMatch(form);
+  checkFormValues(form, "singleuser", "singlepass");
+});
+
+add_task(async function honor_username_autocomplete_off() {
+  const form = createLoginForm({
+    action: "https://autocomplete",
+    username: {
+      autocomplete: "off"
+    }
+  });
+  await promiseFormsProcessedInSameProcess();
+  await SimpleTest.promiseFocus(window);
+  // With the pref toggled off, and with autocomplete=off on the username field,
+  // we expect to have autofilled this form
+  checkFormValues(form, "singleuser", "singlepass");
+});
+
+add_task(async function honor_form_autocomplete_off() {
+  const form = createLoginForm({
+    action: "https://autocomplete",
+    autocomplete: "off"
+  });
+  await promiseFormsProcessedInSameProcess();
+  await SimpleTest.promiseFocus(window);
+  // With the pref toggled off, and with autocomplete=off on the form,
+  // we expect to have autofilled this form
+  checkFormValues(form, "singleuser", "singlepass");
+});
+
+add_task(async function honor_username_and_password_autocomplete_off() {
+  const form = createLoginForm({
+    action: "https://autocomplete",
+    username: {
+      autocomplete: "off"
+    },
+    password: {
+      autocomplete: "off"
+    }
+  });
+  await promiseFormsProcessedInSameProcess();
+  await SimpleTest.promiseFocus(window);
+  // With the pref toggled off, and autocomplete=off on the username and password field,
+  // we expect not to have autofilled this form
+  checkFormValues(form, "", "");
+  // ..but it should autocomplete just fine
+  await autoCompleteFieldsFromFirstMatch(form);
+  checkFormValues(form, "singleuser", "singlepass");
+});
+
+add_task(async function reference_form() {
+  const form = createLoginForm({
+    action: "https://autocomplete"
+  });
+  await promiseFormsProcessedInSameProcess();
+  await SimpleTest.promiseFocus(window);
+  // (this is a control, w/o autocomplete=off, to ensure the login
+  // that was being suppressed would have been filled in otherwise)
+  checkFormValues(form, "singleuser", "singlepass");
+});
+
+add_task(async function honor_username_autocomplete_off_without_password() {
+  const form = createLoginForm({
+    action: "https://autocomplete",
+    username: {
+      id: "username",
+      autocomplete: "off"
+    },
+    password: false
+  });
+  await promiseFormsProcessedInSameProcess();
+  await SimpleTest.promiseFocus(window);
+  // With the pref toggled off, and with autocomplete=off on the username field
+  // in a username-only form, we expect to have autofilled this form
+  is(form.uname.value, "singleuser", `Checking form6 username is: singleuser`);
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_html5.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_html5.html
new file mode 100644
index 0000000000..12aeb0bab3
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_html5.html
@@ -0,0 +1,165 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for html5 input types (email, tel, url, etc.)</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: html5 input types (email, tel, url, etc.)
+<script>
+runChecksAfterCommonInit(() => startTest());
+
+const DEFAULT_ORIGIN = window.location.origin;
+
+runInParent(async function setup() {
+  const login1 = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+  const login2 = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+  const login3 = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+  const login4 = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+  const login5 = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+
+  login1.init("http://mochi.test:8888", "http://bug600551-1", null,
+              "testuser@example.com", "testpass1", "", "");
+  login2.init("http://mochi.test:8888", "http://bug600551-2", null,
+              "555-555-5555", "testpass2", "", "");
+  login3.init("http://mochi.test:8888", "http://bug600551-3", null,
+              "http://mozilla.org", "testpass3", "", "");
+  login4.init("http://mochi.test:8888", "http://bug600551-4", null,
+              "123456789", "testpass4", "", "");
+  login5.init("http://mochi.test:8888", "http://bug600551-5", null,
+              "test", "test", "", "");
+
+  await Services.logins.addLogins([
+    login1,
+    login2,
+    login3,
+    login4,
+    login5,
+  ]);
+});
+</script>
+
+<p id="display"></p>
+<div id="content" style="display: none">
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/* Test for Login Manager: 600551
+  (Password manager not working with input type=email)
+ */
+async function startTest() {
+  const win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <form id="form1" action="http://bug600551-1">
+      <input  type="email"    name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form2" action="http://bug600551-2">
+      <input  type="tel"      name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form3" action="http://bug600551-3">
+      <input  type="url"      name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form4" action="http://bug600551-4">
+      <input  type="number"   name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form5" action="http://bug600551-5">
+      <input  type="search"   name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+      </form>
+
+    <!-- The following forms should not be filled with usernames -->
+    <form id="form6" action="formtest.js">
+      <input  type="datetime" name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form7" action="formtest.js">
+      <input  type="date"     name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form8" action="formtest.js">
+      <input  type="month" name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form9" action="formtest.js">
+      <input  type="week"     name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form10" action="formtest.js">
+      <input  type="time"     name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form11" action="formtest.js">
+      <input  type="datetime-local" name="uname">
+      <input  type="password"       name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form12" action="formtest.js">
+      <input  type="range"    name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>
+
+    <form id="form13" action="formtest.js">
+      <input  type="color"    name="uname">
+      <input  type="password" name="pword">
+      <button type="submit">Submit</button>
+    </form>`, win, 13);
+
+  await checkLoginFormInFrameWithElementValues(win, 1, "testuser@example.com", "testpass1");
+  await checkLoginFormInFrameWithElementValues(win, 2, "555-555-5555", "testpass2");
+  await checkLoginFormInFrameWithElementValues(win, 3, "http://mozilla.org", "testpass3");
+  await checkLoginFormInFrameWithElementValues(win, 4, "123456789", "testpass4");
+  await checkLoginFormInFrameWithElementValues(win, 5, "test", "test");
+
+  info("type=datetime should not be considered a username");
+  await checkLoginFormInFrameWithElementValues(win, 6, "");
+  info("type=date should not be considered a username");
+  await checkLoginFormInFrameWithElementValues(win, 7, "");
+  info("type=month should not be considered a username");
+  await checkLoginFormInFrameWithElementValues(win, 8, "");
+  info("type=week should not be considered a username");
+  await checkLoginFormInFrameWithElementValues(win, 9, "");
+  info("type=time should not be considered a username");
+  await checkLoginFormInFrameWithElementValues(win, 10, "");
+  info("type=datetime-local should not be considered a username");
+  await checkLoginFormInFrameWithElementValues(win, 11, "");
+  info("type=range should not be considered a username");
+  await checkLoginFormInFrameWithElementValues(win, 12, "50");
+  info("type=color should not be considered a username");
+  await checkLoginFormInFrameWithElementValues(win, 13, "#000000");
+
+  SimpleTest.finish();
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_pwevent.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_pwevent.html
new file mode 100644
index 0000000000..4a202a7c05
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_pwevent.html
@@ -0,0 +1,50 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=355063
+-->
+<head>
+  <meta charset="utf-8"/>
+  <title>Test for Bug 355063</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="application/javascript">
+  /** Test for Bug 355063 **/
+  gTestDependsOnDeprecatedLogin = true;
+  runChecksAfterCommonInit(async function startTest() {
+    info("startTest");
+    // Password Manager's own listener should always have been added first, so
+    // the test's listener should be called after the pwmgr's listener fills in
+    // a login.
+    //
+    SpecialPowers.addChromeEventListener("DOMFormHasPassword", function eventFired() {
+      SpecialPowers.removeChromeEventListener("DOMFormHasPassword", eventFired);
+      var passField = $("p1");
+      passField.addEventListener("input", checkForm);
+    });
+    await setFormAndWaitForFieldFilled("<form id=form1>form1: <input id=u1><input type=password id=p1></form><br>",
+                                       {fieldSelector: "#u1", fieldValue: "testuser"});
+  });
+
+  function checkForm() {
+    info("checkForm");
+    var userField = document.getElementById("u1");
+    var passField = document.getElementById("p1");
+    is(userField.value, "testuser", "checking filled username");
+    is(passField.value, "testpass", "checking filled password");
+
+    SimpleTest.finish();
+  }
+</script>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=355063">Mozilla Bug 355063</a>
+<p id="display"></p>
+<div id="content">
+forms go here!
+</div>
+<pre id="test">
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_basic_form_pwonly.html b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_pwonly.html
new file mode 100644
index 0000000000..ec9557d2c3
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_basic_form_pwonly.html
@@ -0,0 +1,193 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test forms and logins without a username</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: forms and logins without a username.
+<p id="display"></p>
+
+<div id="content" style="display: none">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    ["http://mochi.test:8888", "http://mochi.test:8888", null, "testuser", "testpass", "uname", "pword"],
+    ["http://mochi.test:8888", "http://mochi.test:1111", null, "", "1234"],
+    ["http://mochi.test:8888", "http://mochi.test:8888", null, "", "1234"]
+  );
+});
+
+/** Test for Login Manager: password-only logins **/
+add_task(async function startTest() {
+  const win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(location.origin, `
+    <!-- simple form: no username field, 1 password field -->
+    <form id='form1' action='http://mochi.test:1111/formtest.js'> 1
+        <input type='password' name='pname' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- simple form: no username field, 2 password fields -->
+    <form id='form2' action='http://mochi.test:1111/formtest.js'> 2
+        <input type='password' name='pname1' value=''>
+        <input type='password' name='pname2' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- simple form: no username field, 3 password fields -->
+    <form id='form3' action='http://mochi.test:1111/formtest.js'> 3
+        <input type='password' name='pname1' value=''>
+        <input type='password' name='pname2' value=''>
+        <input type='password' name='pname3' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- simple form: no username field, 5 password fields -->
+    <form id='form4' action='http://mochi.test:1111/formtest.js'> 4
+        <input type='password' name='pname1' value=''>
+        <input type='password' name='pname2' value=''>
+        <input type='password' name='pname3' value=''>
+        <input type='password' name='pname4' value=''>
+        <input type='password' name='pname5' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- 6 password fields, should be ignored. -->
+    <form id='form5' action='http://mochi.test:1111/formtest.js'> 5
+        <input type='password' name='pname1' value=''>
+        <input type='password' name='pname2' value=''>
+        <input type='password' name='pname3' value=''>
+        <input type='password' name='pname4' value=''>
+        <input type='password' name='pname5' value=''>
+        <input type='password' name='pname6' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- 1 username field -->
+    <form id='form6' action='http://mochi.test:1111/formtest.js'> 6
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- 1 username field, with a value set -->
+    <form id='form7' action='http://mochi.test:1111/formtest.js'> 7
+        <input type='text'     name='uname' value='someuser'>
+        <input type='password' name='pname' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!--
+    (The following forms have 2 potentially-matching logins, on is
+    password-only, the other is username+password)
+    -->
+
+    <!-- 1 username field, with value set. Fill in the matching U+P login -->
+    <form id='form8' action='formtest.js'> 8
+        <input type='text'     name='uname' value='testuser'>
+        <input type='password' name='pname' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- 1 username field, with value set. Don't fill in U+P login-->
+    <form id='form9' action='formtest.js'> 9
+        <input type='text'     name='uname' value='someuser'>
+        <input type='password' name='pname' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- 1 username field, too small for U+P login -->
+    <form id='form10' action='formtest.js'> 10
+        <input type='text'     name='uname' value='' maxlength="4">
+        <input type='password' name='pname' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- 1 username field, too small for U+P login -->
+    <form id='form11' action='formtest.js'> 11
+        <input type='text'     name='uname' value='' maxlength="0">
+        <input type='password' name='pname' value=''>
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- 1 username field, too small for U+P login -->
+    <form id='form12' action='formtest.js'> 12
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value='' maxlength="4">
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- 1 username field, too small for either login -->
+    <form id='form13' action='formtest.js'> 13
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value='' maxlength="1">
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>
+
+    <!-- 1 username field, too small for either login -->
+    <form id='form14' action='formtest.js'> 14
+        <input type='text'     name='uname' value=''>
+        <input type='password' name='pname' value='' maxlength="0">
+
+        <button type='submit'>Submit</button>
+        <button type='reset'> Reset </button>
+    </form>`, win, 14);
+
+  await checkLoginFormInFrameWithElementValues(win, 1, "1234");
+  await checkLoginFormInFrameWithElementValues(win, 2, "1234", "");
+  await checkLoginFormInFrameWithElementValues(win, 3, "1234", "", "");
+  await checkLoginFormInFrameWithElementValues(win, 4, "1234");
+  await checkUnmodifiedFormInFrame(win, 5);
+
+  await checkLoginFormInFrameWithElementValues(win, 6, "testuser", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, 7, "someuser", "");
+
+  await checkLoginFormInFrameWithElementValues(win, 8, "testuser", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, 9, "someuser", "");
+
+  await checkLoginFormInFrameWithElementValues(win, 10, "", "1234");
+  await checkLoginFormInFrameWithElementValues(win, 11, "", "1234");
+  await checkLoginFormInFrameWithElementValues(win, 12, "", "1234");
+
+  await checkUnmodifiedFormInFrame(win, 13);
+  await checkUnmodifiedFormInFrame(win, 14);
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_bug_627616.html b/toolkit/components/passwordmgr/test/mochitest/test_bug_627616.html
new file mode 100644
index 0000000000..429ec2269c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_bug_627616.html
@@ -0,0 +1,163 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test bug 627616 related to proxy authentication</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script class="testbody" type="text/javascript">
+    SimpleTest.waitForExplicitFinish();
+
+    var Ci = SpecialPowers.Ci;
+
+    function makeXHR(expectedStatus, expectedText, extra) {
+      var xhr =  new XMLHttpRequest();
+      xhr.open("GET", "authenticate.sjs?" +
+                      "proxy_user=proxy_user&" +
+                      "proxy_pass=proxy_pass&" +
+                      "proxy_realm=proxy_realm&" +
+                      "user=user1name&" +
+                      "pass=user1pass&" +
+                      "realm=mochirealm&" +
+                      extra || "");
+      xhr.onloadend = function() {
+        is(xhr.status, expectedStatus, "xhr.status");
+        is(xhr.statusText, expectedText, "xhr.statusText");
+        runNextTest();
+      };
+      return xhr;
+    }
+
+    function testNonAnonymousCredentials() {
+      var xhr = makeXHR(200, "OK");
+      xhr.send();
+    }
+
+    function testAnonymousCredentials() {
+      // Test that an anonymous request correctly performs proxy authentication
+      var xhr = makeXHR(401, "Authentication required");
+      SpecialPowers.wrap(xhr).channel.loadFlags |= Ci.nsIChannel.LOAD_ANONYMOUS;
+      xhr.send();
+    }
+
+    function testAnonymousNoAuth() {
+      // Next, test that an anonymous request still does not include any non-proxy
+      // authentication headers.
+      var xhr = makeXHR(200, "Authorization header not found", "anonymous=1");
+      SpecialPowers.wrap(xhr).channel.loadFlags |= Ci.nsIChannel.LOAD_ANONYMOUS;
+      xhr.send();
+    }
+
+    var gExpectedDialogs = 0;
+    var gCurrentTest;
+    function runNextTest() {
+      is(gExpectedDialogs, 0, "received expected number of auth dialogs");
+      mm.sendAsyncMessage("prepareForNextTest");
+      mm.addMessageListener("prepareForNextTestDone", function prepared(msg) {
+        mm.removeMessageListener("prepareForNextTestDone", prepared);
+        if (pendingTests.length) {
+          ({expectedDialogs: gExpectedDialogs,
+            test: gCurrentTest} = pendingTests.shift());
+          gCurrentTest.call(this);
+        } else {
+          mm.sendAsyncMessage("cleanup");
+          mm.addMessageListener("cleanupDone", () => {
+            // mm.destroy() is called as a cleanup function by runInParent(), no
+            // need to do it here.
+            SimpleTest.finish();
+          });
+        }
+      });
+    }
+
+    var pendingTests = [{expectedDialogs: 2, test: testNonAnonymousCredentials},
+                        {expectedDialogs: 1, test: testAnonymousCredentials},
+                        {expectedDialogs: 0, test: testAnonymousNoAuth}];
+
+    const mm = runInParent(() => {
+      const { classes: parentCc, interfaces: parentCi } = Components;
+
+      const {NetUtil} = ChromeUtils.importESModule(
+        "resource://gre/modules/NetUtil.sys.mjs"
+      );
+
+      const channel = NetUtil.newChannel({
+        uri: "http://example.com",
+        loadUsingSystemPrincipal: true,
+      });
+
+      const pps = parentCc["@mozilla.org/network/protocol-proxy-service;1"].
+                getService(parentCi.nsIProtocolProxyService);
+      pps.asyncResolve(channel, 0, {
+        async onProxyAvailable(req, uri, pi, status) {
+          const mozproxy = "moz-proxy://" + pi.host + ":" + pi.port;
+          const login1 = parentCc["@mozilla.org/login-manager/loginInfo;1"].
+                      createInstance(parentCi.nsILoginInfo);
+          login1.init(mozproxy, null, "proxy_realm", "proxy_user", "proxy_pass",
+                     "", "");
+
+          const login2 = parentCc["@mozilla.org/login-manager/loginInfo;1"].
+                       createInstance(parentCi.nsILoginInfo);
+          login2.init("http://mochi.test:8888", null, "mochirealm", "user1name",
+                      "user1pass", "", "");
+          await Services.logins.addLogins([login1, login2]);
+
+          sendAsyncMessage("setupDone");
+        },
+        QueryInterface: ChromeUtils.generateQI([parentCi.nsIProtocolProxyCallback]),
+      });
+
+      addMessageListener("prepareForNextTest", message => {
+        parentCc["@mozilla.org/network/http-auth-manager;1"].
+          getService(parentCi.nsIHttpAuthManager).
+          clearAll();
+        sendAsyncMessage("prepareForNextTestDone");
+      });
+
+      const modalType = Services.prefs.getIntPref(
+        "prompts.modalType.httpAuth"
+      );
+      const authPromptIsCommonDialog =
+        modalType === Services.prompt.MODAL_TYPE_WINDOW
+          || (modalType === Services.prompt.MODAL_TYPE_TAB
+            && Services.prefs.getBoolPref(
+        "prompts.tabChromePromptSubDialog",
+        false
+      ));
+
+      const dialogObserverTopic = authPromptIsCommonDialog
+        ? "common-dialog-loaded" : "tabmodal-dialog-loaded";
+
+      function dialogObserver(subj, topic, data) {
+        if (authPromptIsCommonDialog) {
+          subj.Dialog.ui.prompt.document
+          .getElementById("commonDialog")
+          .acceptDialog();
+        } else {
+          const prompt = subj.ownerGlobal.gBrowser.selectedBrowser
+            .tabModalPromptBox.getPrompt(subj);
+          prompt.Dialog.ui.button0.click(); // Accept button
+        }
+        sendAsyncMessage("promptAccepted");
+      }
+
+      Services.obs.addObserver(dialogObserver, dialogObserverTopic);
+
+      addMessageListener("cleanup", message => {
+        Services.obs.removeObserver(dialogObserver, dialogObserverTopic);
+        sendAsyncMessage("cleanupDone");
+      });
+    });
+
+    mm.addMessageListener("promptAccepted", msg => {
+      gExpectedDialogs--;
+    });
+    mm.addMessageListener("setupDone", msg => {
+      runNextTest();
+    });
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_bug_776171.html b/toolkit/components/passwordmgr/test/mochitest/test_bug_776171.html
new file mode 100644
index 0000000000..f7de66a01d
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_bug_776171.html
@@ -0,0 +1,57 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=776171
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 776171 related to HTTP auth</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body onload="startTest()">
+<script class="testbody" type="text/javascript">
+
+/**
+ * This test checks we correctly ignore authentication entry
+ * for a subpath and use creds from the URL when provided when XHR
+ * is used with filled user name and password.
+ *
+ * 1. connect auth2/authenticate.sjs that expects user1:pass1 password
+ * 2. connect a dummy URL at the same path
+ * 3. connect authenticate.sjs that again expects user1:pass1 password
+ *    in this case, however, we have an entry without an identity
+ *    for this path (that is a parent for auth2 path in the first step)
+ */
+
+SimpleTest.waitForExplicitFinish();
+
+function doxhr(URL, user, pass, next) {
+  var xhr = new XMLHttpRequest();
+  if (user && pass) {
+    xhr.open("POST", URL, true, user, pass);
+  } else {
+    xhr.open("POST", URL, true);
+  }
+  xhr.onload = function() {
+    is(xhr.status, 200, "Got status 200");
+    next();
+  };
+  xhr.onerror = function() {
+    ok(false, "request passed");
+    SimpleTest.finish();
+  };
+  xhr.send();
+}
+
+function startTest() {
+  doxhr("auth2/authenticate.sjs?user=user1&pass=pass1&realm=realm1", "user1", "pass1", function() {
+    doxhr("auth2", null, null, function() {
+      doxhr("authenticate.sjs?user=user1&pass=pass1&realm=realm1", "user1", "pass1", SimpleTest.finish);
+    });
+  });
+}
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_case_differences.html b/toolkit/components/passwordmgr/test/mochitest/test_case_differences.html
new file mode 100644
index 0000000000..8a8499b584
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_case_differences.html
@@ -0,0 +1,100 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autocomplete due to multiple matching logins</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: autocomplete due to multiple matching logins
+<p id="display"></p>
+<!-- we presumably can't hide the content for this test. -->
+<div id="content"></div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+/** Test for Login Manager: autocomplete due to multiple matching logins **/
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [location.origin, "https://autocomplete:8888", null, "name", "pass", "uname", "pword"],
+    [location.origin, "https://autocomplete:8888", null, "Name", "Pass", "uname", "pword"],
+    [location.origin, "https://autocomplete:8888", null, "USER", "PASS", "uname", "pword"]
+  );
+})
+
+add_task(async function test_empty_first_entry() {
+  const form = createLoginForm({
+    action: "https://autocomplete:8888"
+  });
+
+  // Make sure initial form is empty.
+  checkLoginForm(form.uname, "", form.pword, "");
+
+  // Trigger autocomplete popup
+  form.uname.focus();
+
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is initially closed");
+  const { items } = await openPopupOn(form.uname);
+  popupState = await getPopupState();
+  is(popupState.selectedIndex, -1, "Check no entries are selected");
+  checkAutoCompleteResults(items, ["name", "Name", "USER"], "example.com", "initial");
+
+  // Check first entry
+  const index0Promise = notifySelectedIndex(0);
+  synthesizeKey("KEY_ArrowDown");
+  await index0Promise;
+  checkLoginForm(form.uname, "", form.pword, ""); // value shouldn't update
+  synthesizeKey("KEY_Enter");
+  await promiseFormsProcessedInSameProcess();
+  checkLoginForm(form.uname, "name", form.pword, "pass");
+});
+
+add_task(async function test_empty_second_entry() {
+  const form = createLoginForm({
+    action: "https://autocomplete:8888"
+  });
+
+  await openPopupOn(form.uname);
+  synthesizeKey("KEY_ArrowDown"); // first
+  synthesizeKey("KEY_ArrowDown"); // second
+  synthesizeKey("KEY_Enter");
+  await promiseFormsProcessedInSameProcess();
+  checkLoginForm(form.uname, "Name", form.pword, "Pass");
+});
+
+add_task(async function test_empty_third_entry() {
+  const form = createLoginForm({
+    action: "https://autocomplete:8888"
+  });
+
+  await openPopupOn(form.uname);
+  synthesizeKey("KEY_ArrowDown"); // first
+  synthesizeKey("KEY_ArrowDown"); // second
+  synthesizeKey("KEY_ArrowDown"); // third
+  synthesizeKey("KEY_Enter");
+  await promiseFormsProcessedInSameProcess();
+  checkLoginForm(form.uname, "USER", form.pword, "PASS");
+});
+
+add_task(async function test_preserve_matching_username_case() {
+  const form = createLoginForm({
+    action: "https://autocomplete:8888"
+  });
+  await promiseFormsProcessedInSameProcess();
+
+  await openPopupOn(form.uname, { inputValue: "user" });
+  // Check that we don't clobber user-entered text when tabbing away
+  // (even with no autocomplete entry selected)
+  synthesizeKey("KEY_Tab");
+  await promiseFormsProcessedInSameProcess();
+  checkLoginForm(form.uname, "user", form.pword, "PASS");
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_dismissed_doorhanger_in_shadow_DOM.html b/toolkit/components/passwordmgr/test/mochitest/test_dismissed_doorhanger_in_shadow_DOM.html
new file mode 100644
index 0000000000..87638b1132
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_dismissed_doorhanger_in_shadow_DOM.html
@@ -0,0 +1,108 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test the password manager dismissed doorhanger can detect username and password fields in a Shadow DOM.</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<iframe></iframe>
+
+<script type="application/javascript">
+add_setup(async () => {
+  const readyPromise = registerRunTests();
+  info("Waiting for setup and page load");
+  await readyPromise;
+
+  // assert that there are no logins
+  const allLogins = await LoginManager.getAllLogins();
+  is(allLogins.length, 0, "There are no logins");
+});
+
+const IFRAME = document.querySelector("iframe");
+const PASSWORD_VALUE = "!@$*";
+const TESTCASES = [
+  // Check that the Shadow DOM version of form_basic.html works
+  {
+    name: "test_form_each_field_in_its_own_shadow_root",
+    filename: "form_basic_shadow_DOM_each_field_in_its_own_shadow_root.html",
+  },
+  // Check that the Shadow DOM version of formless_basic.html works
+  {
+    name: "test_formless_each_field_in_its_own_shadow_root",
+    filename: "formless_basic_shadow_DOM_each_field_in_its_own_shadow_root.html",
+  },
+  // Check that the nested Shadow DOM version of form_basic.html works
+  {
+    name: "test_form_nested_each_field_in_its_own_shadow_root",
+    filename: "form_nested_shadow_DOM_each_field_in_its_own_shadow_root.html",
+  }
+];
+
+async function editPasswordFieldInShadowDOM() {
+  info("Editing the input field in the form with a Shadow DOM");
+  await SpecialPowers.spawn(getIframeBrowsingContext(window, 0), [PASSWORD_VALUE], function(val) {
+      const doc = this.content.document;
+      // Grab the wrapper element to get the shadow root containing the password field
+      let wrapper = doc.getElementById("wrapper-password");
+      if (!wrapper) {
+        // This is a nested Shadow DOM test case
+        const outerWrapper = doc.getElementById("outer-wrapper-password");
+        const outerShadowRoot = outerWrapper.openOrClosedShadowRoot;
+        wrapper = outerShadowRoot.querySelector("#wrapper-password");
+      }
+      // If the ShadowRoot's mode is "closed", it can only be accessed from a chrome-privileged
+      // (Bug 1421568) or addon context (Bug 1439153)
+      const shadowRoot = wrapper.openOrClosedShadowRoot;
+      const passwordField = shadowRoot.querySelector("[name='password']");
+      Assert.equal(passwordField.value, "", "Check password didn't get autofilled");
+      passwordField.setUserInput(val);
+      Assert.equal(passwordField.value, val, "Checking for filled password");
+    }
+  );
+}
+
+async function testForm(testcase) {
+  const iframeLoaded = new Promise(resolve => {
+    IFRAME.addEventListener(
+      "load",
+      function(e) {
+        resolve(true);
+      },
+      { once: true }
+    );
+  });
+
+  // This could complete before the page finishes loading.
+  const formsProcessed = promiseFormsProcessed();
+
+  IFRAME.src = testcase.filename;
+  info("Waiting for test page to load in the iframe");
+  await iframeLoaded;
+
+  info("Waiting for 'input' event listener to be added to the form before editing");
+  await formsProcessed;
+
+  const passwordEditProcessed = getPasswordEditedMessage();
+
+  await editPasswordFieldInShadowDOM();
+
+  info("Waiting for parent process to receive input field edit message from content");
+  await passwordEditProcessed;
+}
+
+for (let testcase of TESTCASES) {
+  const taskName = testcase.name;
+  const tmp = {
+    async [taskName]() {
+      await testForm(testcase);
+    }
+  }
+  add_task(tmp[taskName]);
+}
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_formLike_rootElement_with_Shadow_DOM.html b/toolkit/components/passwordmgr/test/mochitest/test_formLike_rootElement_with_Shadow_DOM.html
new file mode 100644
index 0000000000..06458893ea
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_formLike_rootElement_with_Shadow_DOM.html
@@ -0,0 +1,151 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test that FormLike.rootElement points to right element when the page has Shadow DOM</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+
+<iframe></iframe>
+
+<script type="application/javascript">
+const { LoginFormFactory } = SpecialPowers.ChromeUtils.importESModule(
+  "resource://gre/modules/LoginFormFactory.sys.mjs"
+);
+
+add_setup(async () => {
+  const readyPromise = registerRunTests();
+  info("Waiting for setup and page load");
+  await readyPromise;
+
+  // assert that there are no logins
+  const allLogins = await LoginManager.getAllLogins();
+  is(allLogins.length, 0, "There are no logins");
+});
+
+const IFRAME = document.querySelector("iframe");
+const TESTCASES = [
+  // Check that the Shadow DOM version of form_basic.html works
+  {
+    name: "test_form_each_field_in_its_own_shadow_root",
+    filename: "form_basic_shadow_DOM_each_field_in_its_own_shadow_root.html",
+    hostAndRootElementSelectorTuples: [["span#wrapper-password", "form"]],
+  },
+  {
+    name: "test_form_both_fields_together_in_a_shadow_root",
+    filename: "form_basic_shadow_DOM_both_fields_together_in_a_shadow_root.html",
+    hostAndRootElementSelectorTuples: [["span#wrapper-un-and-pw", "form"]],
+  },
+  {
+    name: "test_form_form_and_fields_together_in_a_shadow_root",
+    filename: "form_basic_shadow_DOM_form_and_fields_together_in_a_shadow_root.html",
+    hostAndRootElementSelectorTuples: [["span#wrapper", "form"]],
+  },
+  // Check that the Shadow DOM version of formless_basic.html works
+  {
+    name: "test_formless_each_field_in_its_own_shadow_root",
+    filename: "formless_basic_shadow_DOM_each_field_in_its_own_shadow_root.html",
+    hostAndRootElementSelectorTuples: [["span#wrapper-password", "html"]],
+  },
+  {
+    name: "test_formless_both_fields_together_in_a_shadow_root",
+    filename: "formless_basic_shadow_DOM_both_fields_together_in_a_shadow_root.html",
+    hostAndRootElementSelectorTuples: [["span#wrapper-un-and-pw", "html"]],
+  },
+  {
+    name: "test_formless_form_and_fields_together_in_a_shadow_root.html",
+    filename: "formless_basic_shadow_DOM_form_and_fields_together_in_a_shadow_root.html",
+    hostAndRootElementSelectorTuples: [["span#wrapper", "html"]],
+  },
+  // Check that the nested Shadow DOM version of form_basic.html works
+  {
+    name: "test_form_nested_each_field_in_its_own_shadow_root",
+    filename: "form_nested_shadow_DOM_each_field_in_its_own_shadow_root.html",
+    hostAndRootElementSelectorTuples: [["span#wrapper-password", "form"]],
+    outerHostElementSelector: "span#outer-wrapper-password",
+  },
+  {
+    name: "test_form_nested_both_fields_together_in_a_shadow_root",
+    filename: "form_nested_shadow_DOM_both_fields_together_in_a_shadow_root.html",
+    hostAndRootElementSelectorTuples: [["span#inner-wrapper", "form"]],
+    outerHostElementSelector: "span#outer-wrapper",
+  },
+  {
+    name: "test_form_nested_form_and_fields_together_in_a_shadow_root",
+    filename: "form_nested_shadow_DOM_form_and_fields_together_in_a_shadow_root.html",
+    hostAndRootElementSelectorTuples: [["span#inner-wrapper", "form"]],
+    outerHostElementSelector: "span#outer-wrapper",
+  },
+  {
+    name: "test_multiple_forms_shadow_DOM_all_known_variants",
+    filename: "multiple_forms_shadow_DOM_all_known_variants.html",
+    hostAndRootElementSelectorTuples: [
+      ["span#outer-wrapper", "html"],
+      ["span#wrapper-password-form-case-1", "form#form-case-1"],
+      ["span#wrapper-form-case-2", "form#form-case-2"],
+      ["span#wrapper-form-case-3", "form#form-case-3"],
+    ],
+    outerHostElementSelector: "span#outer-wrapper",
+  }
+];
+
+async function testForm(testcase) {
+  const iframeLoaded = new Promise(resolve => {
+    IFRAME.addEventListener(
+      "load",
+      function(e) {
+        resolve(true);
+      },
+      { once: true }
+    );
+  });
+
+  // This could complete before the page finishes loading.
+  const numForms = testcase.hostAndRootElementSelectorTuples.length;
+  const formsProcessed = promiseFormsProcessedInSameProcess(numForms);
+
+  IFRAME.src = testcase.filename;
+  info("Waiting for test page to load in the iframe");
+  await iframeLoaded;
+
+  info(`Wait for ${numForms} form(s) to be processed.`);
+  await formsProcessed;
+
+  const iframeDoc = SpecialPowers.wrap(IFRAME.contentWindow).document;
+  for (let [hostElementSelector, rootElementSelector] of testcase.hostAndRootElementSelectorTuples) {
+    info("Get the expected rootElement from the document");
+    let hostElement = iframeDoc.querySelector(hostElementSelector);
+    let outerShadowRoot = null;
+    if (!hostElement) {
+      // Nested Shadow DOM testcase
+      const outerHostElement = iframeDoc.querySelector(testcase.outerHostElementSelector);
+      outerShadowRoot = outerHostElement.openOrClosedShadowRoot;
+      hostElement = outerShadowRoot.querySelector(hostElementSelector);
+    }
+    const shadowRoot = hostElement.openOrClosedShadowRoot;
+    let expectedRootElement = iframeDoc.querySelector(rootElementSelector);
+    if (!expectedRootElement) {
+      // The form itself is inside a ShadowRoot and/or there is a ShadowRoot in between the field and form
+      expectedRootElement =
+        shadowRoot.querySelector(rootElementSelector) ||
+        outerShadowRoot.querySelector(rootElementSelector);
+    }
+    ok(LoginFormFactory.getRootElementsWeakSetForDocument(iframeDoc).has(expectedRootElement), "Ensure formLike.rootElement has the expected value");
+  }
+}
+
+for (let testcase of TESTCASES) {
+  const taskName = testcase.name;
+  const tmp = {
+    async [taskName]() {
+      await testForm(testcase);
+    }
+  }
+  add_task(tmp[taskName]);
+}
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_form_action_1.html b/toolkit/components/passwordmgr/test/mochitest/test_form_action_1.html
new file mode 100644
index 0000000000..21f5f18904
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_form_action_1.html
@@ -0,0 +1,140 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for considering form action</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: Bug 360493
+<script>
+gTestDependsOnDeprecatedLogin = true;
+runChecksAfterCommonInit(() => startTest());
+
+let DEFAULT_ORIGIN = window.location.origin;
+</script>
+<p id="display"></p>
+<div id="content" style="display: none">
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: 360493 (Cross-Site Forms + Password
+    Manager = Security Failure) **/
+
+// This test is designed to make sure variations on the form's |action|
+// and |method| continue to work with the fix for 360493.
+
+async function startTest() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <!-- normal form with normal relative action. -->
+    <form id="form1" action="formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- fully specify the action URL -->
+    <form id="form2" action="http://mochi.test:8888/tests/toolkit/components/passwordmgr/test/formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- fully specify the action URL, and change the path -->
+    <form id="form3" action="http://mochi.test:8888/zomg/wtf/bbq/passwordmgr/test/formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- fully specify the action URL, and change the path and filename -->
+    <form id="form4" action="http://mochi.test:8888/zomg/wtf/bbq/passwordmgr/test/not_a_test.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- specify the action URL relative to the current document-->
+    <form id="form5" action="./formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- specify the action URL relative to the current server -->
+    <form id="form6" action="/tests/toolkit/components/passwordmgr/test/formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- Change the method from get to post -->
+    <form id="form7" action="formtest.js" method="POST">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- Blank action URL specified -->
+    <form id="form8" action="">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- |action| attribute entirely missing -->
+    <form id="form9" >
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- action url as javascript -->
+    <form id="form10" action="javascript:alert('this form is not submitted so this alert should not be invoked');">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>`, win, 10);
+
+  // TODO: action=IP.ADDRESS instead of HOSTNAME?
+  // TODO: test with |base href="http://othersite//"| ?
+
+  for (var i = 1; i <= 9; i++) {
+    // Check form i
+    await checkLoginFormInFrameWithElementValues(win, i, "testuser", "testpass");
+  }
+
+  // The login's formActionOrigin isn't "javascript:", so don't fill it in.
+  await checkLoginFormInFrameWithElementValues(win, 10, "", "");
+
+  SimpleTest.finish();
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_form_action_2.html b/toolkit/components/passwordmgr/test/mochitest/test_form_action_2.html
new file mode 100644
index 0000000000..2eae0958ca
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_form_action_2.html
@@ -0,0 +1,173 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for considering form action</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: Bug 360493
+<script>
+gTestDependsOnDeprecatedLogin = true;
+runChecksAfterCommonInit(() => startTest());
+
+let DEFAULT_ORIGIN = window.location.origin;
+</script>
+<p id="display"></p>
+<div id="content" style="display: none">
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: 360493 (Cross-Site Forms + Password Manager = Security Failure) **/
+
+async function startTest() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <!-- The tests in this page exercise things that shouldn't work. -->
+
+    <!-- Change port # of action URL from 8888 to 7777 -->
+    <form id="form1" action="http://localhost:7777/tests/toolkit/components/passwordmgr/test/formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- No port # in action URL -->
+    <form id="form2" action="http://localhost/tests/toolkit/components/passwordmgr/test/formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- Change protocol from http:// to ftp://, include the expected 8888 port # -->
+    <form id="form3" action="ftp://localhost:8888/tests/toolkit/components/passwordmgr/test/formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- Change protocol from http:// to ftp://, no port # specified -->
+    <form id="form4" action="ftp://localhost/tests/toolkit/components/passwordmgr/test/formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- Try a weird URL. -->
+    <form id="form5" action="about:blank">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- Try a weird URL. (If the normal embedded action URL doesn't work, that should mean other URLs won't either) -->
+    <form id="form6" action="view-source:http://localhost:8888/tests/toolkit/components/passwordmgr/test/formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- Try a weird URL. -->
+    <form id="form7" action="view-source:formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- Action URL points to a different host (this is the archetypical exploit) -->
+    <form id="form8" action="http://www.cnn.com/">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- Action URL points to a different host, user field prefilled -->
+    <form id="form9" action="http://www.cnn.com/">
+      <input  type="text"       name="uname" value="testuser">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- Try wrapping a evil form around a good form, to see if we can confuse the parser. -->
+    <form id="form10-A" action="http://www.cnn.com/">
+     <form id="form10-B" action="formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit (inner)</button>
+      <button type="reset"> Reset  (inner)</button>
+     </form>
+     <button type="submit" id="neutered_submit10">Submit (outer)</button>
+     <button type="reset">Reset (outer)</button>
+    </form>
+
+    <!-- Try wrapping a good form around an evil form, to see if we can confuse the parser. -->
+    <form id="form11-A" action="formtest.js">
+     <form id="form11-B" action="http://www.cnn.com/">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+
+      <button type="submit">Submit (inner)</button>
+      <button type="reset"> Reset  (inner)</button>
+     </form>
+     <button type="submit" id="neutered_submit11">Submit (outer)</button>
+     <button type="reset">Reset (outer)</button>
+    </form>`, win, 11);
+
+  // TODO: probably should have some accounts which have no port # in the action url.
+  // JS too. And different host/proto.
+  // TODO: www.site.com vs. site.com?
+  // TODO: foo.site.com vs. bar.site.com?
+
+  for (var i = 1; i <= 8; i++) {
+    // Check form i
+    await checkLoginFormInFrameWithElementValues(win, i, "", "");
+  }
+
+  await checkLoginFormInFrameWithElementValues(win, 9, "testuser", "");
+
+  await checkLoginFormInFrameWithElementValues(win, "10-A", "", "");
+
+  // The DOM indicates this form could be filled, as the evil inner form
+  // is discarded. And yet pwmgr seems not to fill it. Not sure why.
+  todo(false, "Mangled form combo not being filled when maybe it could be?");
+  await checkLoginFormInFrameWithElementValues(win, "11-A", "testuser", "testpass");
+
+  // Verify this by making sure there are no extra forms in the document, and
+  // that the submit button for the neutered forms don't do anything.
+  // If the test finds extra forms the submit() causes the test to timeout, then
+  // there may be a security issue.
+  await SpecialPowers.spawn(win, [], async function submitForms() {
+    is(this.content.document.forms.length, 11, "Checking for unexpected forms");
+    this.content.document.getElementById("neutered_submit10").click();
+    this.content.document.getElementById("neutered_submit11").click();
+  });
+
+  SimpleTest.finish();
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_form_action_javascript.html b/toolkit/components/passwordmgr/test/mochitest/test_form_action_javascript.html
new file mode 100644
index 0000000000..717805f06a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_form_action_javascript.html
@@ -0,0 +1,44 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test forms with a JS submit action</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: form with JS submit action
+<script>
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [location.origin, "javascript:", null, "jsuser", "jspass123", "uname", "pword"]
+  );
+});
+
+/** Test for Login Manager: JS action URL **/
+add_task(async function startTest() {
+  const win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(location.origin, `
+    <form id='form1' action='javascript:alert("never shows")'> 1
+      <input name="uname">
+      <input name="pword" type="password">
+
+      <button type='submit'>Submit</button>
+      <button type='reset'> Reset </button>
+    </form>`, win);
+
+  await checkLoginFormInFrameWithElementValues(win, 1, "jsuser", "jspass123");
+});
+</script>
+
+<p id="display"></p>
+
+<div id="content" style="display: none">
+</div>
+
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_formless_autofill.html b/toolkit/components/passwordmgr/test/mochitest/test_formless_autofill.html
new file mode 100644
index 0000000000..4d1b7582a9
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_formless_autofill.html
@@ -0,0 +1,140 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test autofilling of fields outside of a form</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script type="application/javascript">
+gTestDependsOnDeprecatedLogin = true;
+let doneSetupPromise = new Promise(resolve => {
+  document.addEventListener("DOMContentLoaded", () => {
+    document.getElementById("loginFrame").addEventListener("load", async evt => {
+      // Tell the parent to setup test logins.
+      await runChecksAfterCommonInit();
+      resolve();
+    });
+  });
+});
+
+add_setup(async () => {
+  info("Waiting for loads and setup");
+  await doneSetupPromise;
+
+  await loadRecipes({
+    siteRecipes: [{
+      hosts: ["mochi.test:8888"],
+      usernameSelector: "input[name='recipeuname']",
+      passwordSelector: "input[name='recipepword']",
+    }],
+  });
+});
+
+
+const DEFAULT_ORIGIN = "http://mochi.test:8888";
+const TESTCASES = [
+  {
+    // Inputs
+    document: `<input type=password>`,
+
+    // Expected outputs
+    expectedInputValues: ["testpass"],
+  },
+  {
+    document: `<input>
+      <input type=password>`,
+    expectedInputValues: ["testuser", "testpass"],
+  },
+  {
+    document: `<input>
+      <input type=password>
+      <input type=password>`,
+    expectedInputValues: ["testuser", "testpass", ""],
+  },
+  {
+    document: `<input>
+      <input type=password>
+      <input type=password>
+      <input type=password>`,
+    expectedInputValues: ["testuser", "testpass", "", ""],
+  },
+  {
+    document: `<input>
+      <input type=password form="form1">
+      <input type=password>
+      <form id="form1">
+        <input>
+        <input type=password>
+      </form>`,
+    expectedFormCount: 2,
+    expectedInputValues: ["testuser", "testpass", "testpass", "", ""],
+  },
+  {
+    document: `<!-- formless password field selector recipe test -->
+      <input>
+      <input type=password>
+      <input>
+      <input type=password name="recipepword">`,
+    expectedInputValues: ["", "", "testuser", "testpass"],
+  },
+  {
+    document: `<!-- formless username and password field selector recipe test -->
+      <input name="recipeuname">
+      <input>
+      <input type=password>
+      <input type=password name="recipepword">`,
+    expectedInputValues: ["testuser", "", "", "testpass"],
+  },
+  {
+    document: `<!-- form and formless recipe field selector test -->
+      <input name="recipeuname">
+      <input>
+      <input type=password form="form1"> <!-- not filled since recipe affects both FormLikes -->
+      <input type=password>
+      <input type=password name="recipepword">
+      <form id="form1">
+        <input>
+        <input type=password>
+      </form>`,
+    expectedFormCount: 2,
+    expectedInputValues: ["testuser", "", "", "", "testpass", "", ""],
+  },
+];
+
+add_task(async function test() {
+  let loginFrame = document.getElementById("loginFrame");
+  let frameDoc = loginFrame.contentWindow.document;
+
+  for (let tc of TESTCASES) {
+    info("Starting testcase: " + JSON.stringify(tc));
+
+    let numFormLikesExpected = tc.expectedFormCount || 1;
+
+    let processedFormPromise = promiseFormsProcessedInSameProcess(numFormLikesExpected);
+
+    frameDoc.documentElement.innerHTML = tc.document;
+    info("waiting for " + numFormLikesExpected + " processed form(s)");
+    await processedFormPromise;
+
+    let testInputs = frameDoc.documentElement.querySelectorAll("input");
+    is(testInputs.length, tc.expectedInputValues.length, "Check number of inputs");
+    for (let i = 0; i < tc.expectedInputValues.length; i++) {
+      let expectedValue = tc.expectedInputValues[i];
+      is(testInputs[i].value, expectedValue, `Check expected input value ${i} : ${expectedValue}`);
+    }
+  }
+});
+
+</script>
+
+<p id="display"></p>
+
+<div id="content">
+  <iframe id="loginFrame" src="http://mochi.test:8888/tests/toolkit/components/passwordmgr/test/blank.html"></iframe>
+</div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_formless_submit.html b/toolkit/components/passwordmgr/test/mochitest/test_formless_submit.html
new file mode 100644
index 0000000000..4e98fd1b9a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_formless_submit.html
@@ -0,0 +1,242 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test capturing of fields outside of a form</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script type="application/javascript">
+const { LoginFormFactory } = SpecialPowers.ChromeUtils.importESModule(
+  "resource://gre/modules/LoginFormFactory.sys.mjs"
+);
+const { LoginManagerChild } = SpecialPowers.ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerChild.sys.mjs"
+);
+
+function loadFrame() {
+  return new Promise(resolve => {
+    document.getElementById("loginFrame").addEventListener("load", (evt) => {
+      if (evt.target.contentWindow.location.href.includes("blank.html")) {
+        resolve();
+      }
+    });
+  });
+}
+
+let loadPromise = new Promise(resolve => {
+  document.addEventListener("DOMContentLoaded", () => {
+    resolve(loadFrame());
+  });
+});
+
+add_setup(async () => {
+  info("Waiting for page and frame loads");
+  await loadPromise;
+
+  await loadRecipes({
+    siteRecipes: [{
+      hosts: ["mochi.test:8888"],
+      usernameSelector: "input[name='recipeuname']",
+      passwordSelector: "input[name='recipepword']",
+    }],
+  });
+});
+
+const DEFAULT_ORIGIN = "http://mochi.test:8888";
+const TESTCASES = [
+  {
+    // Inputs
+    document: `<input type=password value="">`,
+    selectorValues: {
+      "[type=password]": "pass1",
+    },
+    inputIndexForFormLike: 0,
+    expectedFormsCount: 1,
+
+    // Expected outputs similar to PasswordManager:onFormSubmit
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: null,
+    newPasswordFieldValue: "pass1",
+    oldPasswordFieldValue: null,
+  },
+  {
+    document: `<input id="u1" value="">
+      <input type=password value="">`,
+    selectorValues: {
+      "#u1": "user1",
+      "[type=password]": "pass1",
+    },
+    inputIndexForFormLike: 0,
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass1",
+    oldPasswordFieldValue: null,
+  },
+  {
+    document: `<input id="u1" value="">
+      <input type=password value="">`,
+    selectorValues: {
+      "#u1": "user1",
+      "[type=password]": "pass1",
+    },
+    inputIndexForFormLike: 1,
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass1",
+    oldPasswordFieldValue: null,
+  },
+  {
+    document: `<input id="u1" value="">
+      <input id="p1" type=password value="">
+      <input id="p2" type=password value="">`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "pass1",
+      "#p2": "pass2",
+    },
+    inputIndexForFormLike: 2,
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: "pass1",
+  },
+  {
+    document: `<input id="u1" value="">
+      <input id="p1" type=password value="">
+      <input id="p2" type=password value="">
+      <input id="p3" type=password value="">`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "pass1",
+      "#p2": "pass2",
+      "#p3": "pass2",
+    },
+    inputIndexForFormLike: 3,
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: "pass1",
+  },
+  {
+    document: `<input id="u1" value="">
+      <input id="p1" type=password value="" form="form1">
+      <input id="p2" type=password value="">
+      <form id="form1">
+        <input id="u2" value="">
+        <input id="p3" type=password value="">
+      </form>`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "user2",
+      "#p2": "pass1",
+      "#u2": "user3",
+      "#p3": "pass2",
+    },
+    inputIndexForFormLike: 2,
+    expectedFormsCount: 2,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass1",
+    oldPasswordFieldValue: null,
+  },
+  {
+    document: `<!-- recipe field override -->
+      <input name="recipeuname" value="">
+      <input id="u1" value="">
+      <input id="p1" type=password value="">
+      <input name="recipepword" type=password value="">`,
+    selectorValues: {
+      "[name='recipeuname']": "username from recipe",
+      "#u1": "default field username",
+      "#p1": "pass1",
+      "[name='recipepword']": "pass2",
+    },
+    inputIndexForFormLike: 2,
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "username from recipe",
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: null,
+  },
+];
+
+let count = 0;
+async function testFormlessSubmit(tc) {
+  let loginFrame = document.getElementById("loginFrame");
+
+  let frameDoc = SpecialPowers.wrap(loginFrame.contentWindow).document;
+  info("Starting testcase: " + JSON.stringify(tc));
+
+  let formsProcessed = promiseFormsProcessedInSameProcess(tc.expectedFormsCount);
+  frameDoc.documentElement.innerHTML = tc.document;
+  await formsProcessed;
+  // We eliminate no user input as a reason for not capturing by modifying the value
+  setUserInputValues(frameDoc.documentElement, tc.selectorValues);
+
+  let inputForFormLike = frameDoc.querySelectorAll("input")[tc.inputIndexForFormLike];
+
+  let formLike = LoginFormFactory.createFromField(inputForFormLike);
+
+  info("Calling _onFormSubmit with FormLike");
+  let submitProcessed = getSubmitMessage();
+  LoginManagerChild.forWindow(frameDoc.defaultView)._onFormSubmit(formLike);
+
+  let { origin, data } = await submitProcessed;
+
+  // Check data sent via PasswordManager:onFormSubmit
+  is(origin, tc.origin, "Check origin");
+  is(data.formActionOrigin, tc.formActionOrigin, "Check formActionOrigin");
+
+  if (tc.usernameFieldValue === null) {
+    is(data.usernameField, tc.usernameFieldValue, "Check usernameField");
+  } else {
+    is(data.usernameField.value, tc.usernameFieldValue, "Check usernameField");
+  }
+
+  is(data.newPasswordField.value, tc.newPasswordFieldValue, "Check newPasswordFieldValue");
+
+  if (tc.oldPasswordFieldValue === null) {
+    is(data.oldPasswordField, tc.oldPasswordFieldValue, "Check oldPasswordFieldValue");
+  } else {
+    is(data.oldPasswordField.value, tc.oldPasswordFieldValue, "Check oldPasswordFieldValue");
+  }
+
+  loadPromise = loadFrame();
+  loginFrame.contentWindow.location =
+    "http://mochi.test:8888/tests/toolkit/components/passwordmgr/test/mochitest/blank.html?" + count++;
+  await loadPromise;
+}
+
+for (let tc of TESTCASES) {
+  let taskName = "testcase-" + count++;
+  let tmp = {
+    async [taskName]() {
+      await testFormlessSubmit(tc);
+    },
+  };
+  add_task(tmp[taskName]);
+}
+</script>
+
+<p id="display"></p>
+
+<div id="content">
+  <iframe id="loginFrame" src="http://mochi.test:8888/tests/toolkit/components/passwordmgr/test/mochitest/blank.html"></iframe>
+</div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_form_removal.html b/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_form_removal.html
new file mode 100644
index 0000000000..5512c57db2
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_form_removal.html
@@ -0,0 +1,287 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test capturing of fields due to form removal</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script type="application/javascript">
+let loadPromise = new Promise(resolve => {
+  document.addEventListener("DOMContentLoaded", () => {
+    document.getElementById("loginFrame").addEventListener("load", (evt) => {
+      resolve();
+    });
+  });
+});
+
+add_setup(async () => {
+  info("Waiting for page and frame loads");
+  await loadPromise;
+
+  await loadRecipes({
+    siteRecipes: [{
+      hosts: ["test1.mochi.test:8888"],
+      usernameSelector: "input[name='recipeuname']",
+      passwordSelector: "input[name='recipepword']",
+    }],
+  });
+});
+
+const DEFAULT_ORIGIN = "http://test1.mochi.test:8888";
+const SCRIPTS = {
+  // Test removing the form(or form-less password field), their parent node, and the top-level node.
+  REMOVE_FORM: `let e = document.querySelector("form"); e.parentNode.removeChild(e);`,
+  REMOVE_PASSWORD: `let e = document.querySelector("[type=password]"); e.parentNode.removeChild(e);`,
+  REMOVE_FORM_PARENT: `let e = document.querySelector("form").parentNode; e.parentNode.removeChild(e);`,
+  REMOVE_PASSWORD_PARENT: `let e = document.querySelector("[type=password]").parentNode; e.parentNode.removeChild(e);`,
+  REMOVE_TOP: `let e = document.querySelector("html"); e.parentNode.removeChild(e);`,
+
+  // Add testcases related to page navigation here to ensure these cases still work
+  // when we have set up form removal observer.
+  PUSHSTATE: `history.pushState({}, "Pushed state", "?pushed");`,
+  WINDOW_LOCATION: `window.location = "data:text/html;charset=utf-8,window.location";`,
+};
+const TESTCASES = [
+  {
+    // Inputs
+    document: `<input type=password value="">`,
+    selectorValues: {
+      "[type=password]": "pass1",
+    },
+    expectedFormsCount: 1,
+
+    // Expected outputs similar to PasswordManager:onFormSubmit
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: null,
+    newPasswordFieldValue: "pass1",
+    oldPasswordFieldValue: null,
+  },
+  {
+    document: `<input id="u1" value="">
+      <input type=password value="">`,
+    selectorValues: {
+      "#u1": "user1",
+      "[type=password]": "pass1",
+    },
+
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass1",
+    oldPasswordFieldValue: null,
+  },
+  {
+    document: `<input id="u1" value="">
+      <input id="p1" type=password value="">
+      <input id="p2" type=password value="">`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "pass1",
+      "#p2": "pass2",
+    },
+
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: "pass1",
+  },
+  {
+    document: `<input id="u1" value="">
+      <input id="p1" type=password value="">
+      <input id="p2" type=password value="">
+      <input id="p3" type=password value="">`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "pass1",
+      "#p2": "pass2",
+      "#p3": "pass2",
+    },
+
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: "pass1",
+  },
+  {
+    // Since there are two FormLikes to auto-submit in this case we mark
+    // one FormLike's password fields with a magic "ignore-form-submission"
+    // value so we can just focus on the other form. We then repeat the testcase
+    // below with the other FormLike ignored.
+    document: `<input id="u1" value="">
+      <input type=password id="p1" value="" form="form1">
+      <input type=password id="p2" value="">
+      <form id="form1">
+        <input id="u2" value="">
+        <input id="p3" type=password value="">
+      </form>`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "ignore-form-submission",
+      "#p2": "pass1",
+      "#u2": "user3",
+      "#p3": "ignore-form-submission",
+    },
+    expectedFormsCount: 2,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass1",
+    oldPasswordFieldValue: null,
+    removePassword: true,
+  },
+  { // Same as above but with the other form ignored.
+    document: `<input id="u1" value="">
+      <input id="p1" type=password value="" form="form1">
+      <input id="p2" type=password value="">
+      <form id="form1">
+        <input id="u2" value="">
+        <input id="p3" type=password value="">
+      </form>`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "pass2",
+      "#p2": "ignore-form-submission",
+      "#u2": "user3",
+      "#p3": "pass2",
+    },
+
+    expectedFormsCount: 2,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: null,
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: null,
+  },
+  /*
+ XXX - Bug 1698498 :
+ This test case fails because when we call querySelector in LoginRecipes.jsm
+ after the form is removed, querySelector can't find the element.
+  {
+    document: `<!-- recipe field override -->
+      <input name="recipeuname" value="">
+      <input id="u1" value="">
+      <input id="p1" type=password value="">
+      <input name="recipepword" type=password value="">`,
+    selectorValues: {
+      "[name='recipeuname']": "username from recipe",
+      "#u1": "default field username",
+      "#p1": "pass1",
+      "[name='recipepword']": "pass2",
+    },
+
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "username from recipe",
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: null,
+  },*/
+];
+
+function filterFormSubmissions({ origin, data }) {
+  return data.newPasswordField.value != "ignore-form-submission";
+}
+
+async function testFormlesSubmitFormRemoval(tc, testDoc, scriptName) {
+  let loginFrame = document.getElementById("loginFrame");
+  let loadedPromise = new Promise((resolve) => {
+    loginFrame.addEventListener("load", function() {
+      resolve();
+    }, {once: true});
+  });
+  loginFrame.src = DEFAULT_ORIGIN + "/tests/toolkit/components/passwordmgr/test/mochitest/blank.html";
+  await loadedPromise;
+
+  let frameDoc = SpecialPowers.wrap(loginFrame.contentWindow).document;
+
+  let formsProcessed = promiseFormsProcessed(tc.expectedFormsCount);
+  frameDoc.documentElement.innerHTML = testDoc;
+  await formsProcessed;
+  // We eliminate no user input as a reason for not capturing by modifying the value
+  setUserInputValues(frameDoc.documentElement, tc.selectorValues)
+
+  await SpecialPowers.spawn(frameDoc.defaultView, [], async () => {
+    await content.fetch("http://test1.mochi.test:8888/tests/toolkit/components/passwordmgr/test/mochitest/blank.html");
+  });
+
+  let submitProcessed = getSubmitMessage(filterFormSubmissions);
+  info("Running " + scriptName + " script to cause a submission");
+  frameDoc.defaultView.eval(SCRIPTS[scriptName]);
+
+  info("Waiting for formSubmissionProcsssed message");
+  let { origin, data } = await submitProcessed;
+  info("Got for formSubmissionProcsssed message");
+
+  // Check data sent via PasswordManager:onFormSubmit
+  is(origin, tc.origin, "Check origin");
+  is(data.formActionOrigin, tc.formActionOrigin, "Check formActionOrigin");
+
+  if (tc.usernameFieldValue === null) {
+    is(data.usernameField, tc.usernameFieldValue, "Check usernameField");
+  } else {
+    is(data.usernameField.value, tc.usernameFieldValue, "Check usernameField");
+  }
+
+  is(data.newPasswordField.value, tc.newPasswordFieldValue, "Check newPasswordFieldValue");
+
+  if (tc.oldPasswordFieldValue === null) {
+    is(data.oldPasswordField, tc.oldPasswordFieldValue, "Check oldPasswordFieldValue");
+  } else {
+    is(data.oldPasswordField.value, tc.oldPasswordFieldValue, "Check oldPasswordFieldValue");
+  }
+};
+
+let count = 0;
+for (let tc of TESTCASES) {
+  for (let scriptName of Object.keys(SCRIPTS)) {
+    for (let surroundDocumentWithForm of [false, true]) {
+      let testDoc = tc.document;
+      if (surroundDocumentWithForm) {
+        if (testDoc.includes("<form")) {
+          info("Skipping surroundDocumentWithForm case since document already contains a <form>");
+          continue;
+        }
+        testDoc = "<form>" + testDoc + "</form>";
+      }
+
+      if (["REMOVE_FORM", "REMOVE_FORM_PARENT"].includes(scriptName) &&
+          (!testDoc.includes("<form") || tc.removePassword)) {
+        continue;
+      } else if (["REMOVE_PASSWORD","REMOVE_PASSWORD_PARENT"].includes(scriptName) &&
+                 testDoc.includes("<form")) {
+        continue;
+      }
+
+      let taskName = `testcase-${count}-${scriptName}${surroundDocumentWithForm ? '-formWrapped' : ''}`;
+      let tmp = {
+        async [taskName]() {
+          info("Starting testcase with script " + scriptName + " and " +
+               (surroundDocumentWithForm ? "a" : "no") + " form wrapper: " + JSON.stringify(tc));
+          await testFormlesSubmitFormRemoval(tc, testDoc, scriptName);
+        },
+      };
+      add_task(tmp[taskName]);
+    }
+  }
+  count++;
+}
+
+</script>
+
+<p id="display"></p>
+
+<div id="content">
+  <iframe id="loginFrame" src="http://test1.mochi.test:8888/tests/toolkit/components/passwordmgr/test/mochitest/blank.html"></iframe>
+</div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_form_removal_negative.html b/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_form_removal_negative.html
new file mode 100644
index 0000000000..dfd7670a12
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_form_removal_negative.html
@@ -0,0 +1,204 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test no capturing of fields outside of a form due to navigation</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script type="application/javascript">
+SimpleTest.requestFlakyTimeout("Testing that a message doesn't arrive");
+
+let loadPromise = new Promise(resolve => {
+  document.addEventListener("DOMContentLoaded", () => {
+    document.getElementById("loginFrame").addEventListener("load", (evt) => {
+      resolve();
+    });
+  });
+});
+
+function submissionProcessed(...args) {
+  ok(false, "No formSubmissionProcessed should occur in this test");
+  info("got: " + JSON.stringify(args));
+}
+
+add_setup(async () => {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["signon.formRemovalCapture.enabled", true],
+    ],
+  });
+
+  info("Waiting for page and frame loads");
+  await loadPromise;
+
+  PWMGR_COMMON_PARENT.addMessageListener("formSubmissionProcessed", submissionProcessed);
+
+  SimpleTest.registerCleanupFunction(() => {
+    PWMGR_COMMON_PARENT.removeMessageListener("formSubmissionProcessed", submissionProcessed);
+  });
+});
+
+const DEFAULT_ORIGIN = "http://test1.mochi.test:8888";
+const SCRIPTS = {
+  // Test form submission is not triggered when there is no user interaction and
+  // no ajax request fired previously.
+  REMOVE_TOP: `let e = document.querySelector("html"); e.parentNode.removeChild(e);`,
+
+  // Test the following scripts don't trigger form submissions because of the
+  // form removal heuristics
+  PUSHSTATE: `history.pushState({}, "Pushed state", "?pushed");`,
+  WINDOW_LOCATION: `window.location = "data:text/html;charset=utf-8,window.location";`,
+  WINDOW_LOCATION_RELOAD: `window.location.reload();`,
+  HISTORY_BACK: `history.back();`,
+  HISTORY_GO_MINUS1: `history.go(-1);`,
+};
+
+const HEURISTICS = [
+  {
+    userInput: true,
+    ajaxSuccess: true,
+  },
+  {
+    userInput: false,
+    ajaxSuccess: true,
+  },
+  {
+    userInput: true,
+    ajaxSuccess: false,
+  },
+  {
+    userInput: false,
+    ajaxSuccess: false,
+  },
+];
+
+const TESTCASES = [
+  // Begin test cases that shouldn't trigger capture.
+  {
+    // Empty password field in a form
+    document: `<form><input type=password value="xxx"></form>`,
+    selectorValues: {
+      "[type=password]": "",
+    },
+  },
+  {
+    // Empty password field
+    document: `<input type=password value="">`,
+    selectorValues: {
+      "[type=password]": "",
+    },
+  },
+  {
+    // Test with an input that would normally be captured but with SCRIPTS that
+    // shouldn't trigger capture.
+    document: `<input type=password value="">`,
+    selectorValues: {
+      "[type=password]": "pass2",
+    },
+    wouldCapture: true,
+  },
+  {
+    // Test with an input that would normally be captured but with SCRIPTS that
+    // shouldn't trigger capture.
+    document: `<form><input type=password value=""></form>`,
+    selectorValues: {
+      "[type=password]": "pass2",
+    },
+    wouldCapture: true,
+  },
+];
+
+async function testFormlesSubmitNavigationNegative(tc, scriptName, heuristic) {
+  let loginFrame = document.getElementById("loginFrame");
+  let waitTime;
+  let android = navigator.appVersion.includes("Android");
+  if (android) {
+    // intermittent failures on Android Debug at 5 seconds
+    waitTime = 10000;
+  } else {
+    waitTime = 5000;
+  }
+
+  let loadedPromise = new Promise((resolve) => {
+    loginFrame.addEventListener("load", function() {
+      resolve();
+    }, {once: true});
+  });
+
+  loginFrame.src = DEFAULT_ORIGIN + "/tests/toolkit/components/passwordmgr/test/mochitest/blank.html";
+  await loadedPromise;
+
+  let frameDoc = SpecialPowers.wrap(loginFrame.contentWindow).document;
+  let formsProcessed = promiseFormsProcessed();
+  frameDoc.documentElement.innerHTML = tc.document;
+  await formsProcessed;
+
+  // We eliminate no user input as a reason for not capturing by modifying the value
+  setUserInputValues(frameDoc.documentElement, tc.selectorValues, heuristic.userInput);
+
+  if (heuristic.ajaxSuccess) {
+    await SpecialPowers.spawn(frameDoc.defaultView, [], async () => {
+      await content.fetch("http://test1.mochi.test:8888/tests/toolkit/components/passwordmgr/test/mochitest/blank.html");
+    });
+  }
+
+  info("Running " + scriptName + " script to check for a submission");
+  frameDoc.defaultView.eval(SCRIPTS[scriptName]);
+
+  info("Running " + scriptName + " script to check for a submission 1");
+  // Wait to see if the promise above resolves.
+  await new Promise(resolve => setTimeout(resolve, waitTime));
+  info("Running " + scriptName + " script to check for a submission 2");
+  ok(true, "Done waiting for captures");
+
+}
+
+let count = 0;
+for (let tc of TESTCASES) {
+  for (let scriptName of Object.keys(SCRIPTS)) {
+    for (let heuristic of HEURISTICS) {
+      let shouldCaptureAFormRemoval = heuristic.ajaxSuccess && heuristic.userInput;
+      // Only run the following scripts when we are going to observeform removal change
+      // to save some time running this whole test.
+      if (["PUSHSTATE", "WINDOW_LOCATION", "WINDOW_LOCATION_RELOAD", "HISTORY_BACK", "HISTORY_GO_MINUS1"].includes(scriptName)) {
+        if(!shouldCaptureAFormRemoval) {
+          continue;
+        }
+
+        if (tc.wouldCapture && ["PUSHSTATE", "WINDOW_LOCATION"].includes(scriptName)) {
+          // Don't run scripts that should actually capture for this testcase.
+          continue;
+        }
+      } else if (["REMOVE_TOP"].includes(scriptName)) {
+        if (shouldCaptureAFormRemoval) {
+          // Don't run scripts that should actually capture for this testcase.
+          continue;
+        }
+      }
+
+      let taskName = `testcase-${count}-${scriptName}`;
+      let tmp = {
+        async [taskName]() {
+          info("Starting testcase with script " + scriptName + ": " + JSON.stringify(tc) + ": " + JSON.stringify(heuristic));
+          await testFormlesSubmitNavigationNegative(tc, scriptName, heuristic);
+        },
+      };
+      add_task(tmp[taskName]);
+    }
+  }
+}
+
+
+</script>
+
+<p id="display"></p>
+
+<div id="content">
+  <iframe id="loginFrame" src="http://test1.mochi.test:8888/tests/toolkit/components/passwordmgr/test/mochitest/blank.html"></iframe>
+</div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_navigation.html b/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_navigation.html
new file mode 100644
index 0000000000..348669a85c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_navigation.html
@@ -0,0 +1,267 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test capturing of fields outside of a form due to navigation</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script type="application/javascript">
+let loadPromise = new Promise(resolve => {
+  document.addEventListener("DOMContentLoaded", () => {
+    document.getElementById("loginFrame").addEventListener("load", (evt) => {
+      resolve();
+    });
+  });
+});
+
+add_setup(async () => {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["signon.formlessCapture.enabled", true],
+    ],
+  });
+
+  info("Waiting for page and frame loads");
+  await loadPromise;
+
+  await loadRecipes({
+    siteRecipes: [{
+      hosts: ["test1.mochi.test:8888"],
+      usernameSelector: "input[name='recipeuname']",
+      passwordSelector: "input[name='recipepword']",
+    }],
+  });
+});
+
+const DEFAULT_ORIGIN = "http://test1.mochi.test:8888";
+const SCRIPTS = {
+  PUSHSTATE: `history.pushState({}, "Pushed state", "?pushed");`,
+  WINDOW_LOCATION: `window.location = "data:text/html;charset=utf-8,window.location";`,
+};
+const TESTCASES = [
+  {
+    // Inputs
+    document: `<input type=password value="">`,
+    selectorValues: {
+      "[type=password]": "pass1",
+    },
+    expectedFormsCount: 1,
+
+    // Expected outputs similar to PasswordManager:onFormSubmit
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: null,
+    newPasswordFieldValue: "pass1",
+    oldPasswordFieldValue: null,
+  },
+  {
+    document: `<input id="u1" value="">
+      <input type=password value="">`,
+    selectorValues: {
+      "#u1": "user1",
+      "[type=password]": "pass1",
+    },
+
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass1",
+    oldPasswordFieldValue: null,
+  },
+  {
+    document: `<input id="u1" value="">
+      <input id="p1" type=password value="">
+      <input id="p2" type=password value="">`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "pass1",
+      "#p2": "pass2",
+    },
+
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: "pass1",
+  },
+  {
+    document: `<input id="u1" value="">
+      <input id="p1" type=password value="">
+      <input id="p2" type=password value="">
+      <input id="p3" type=password value="">`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "pass1",
+      "#p2": "pass2",
+      "#p3": "pass2",
+    },
+
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: "pass1",
+  },
+  {
+    // Since there are two FormLikes to auto-submit in this case we mark
+    // one FormLike's password fields with a magic "ignore-form-submission"
+    // value so we can just focus on the other form. We then repeat the testcase
+    // below with the other FormLike ignored.
+    document: `<input id="u1" value="">
+      <input type=password id="p1" value="" form="form1">
+      <input type=password id="p2" value="">
+      <form id="form1">
+        <input id="u2" value="">
+        <input id="p3" type=password value="">
+      </form>`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "ignore-form-submission",
+      "#p2": "pass1",
+      "#u2": "user3",
+      "#p3": "ignore-form-submission",
+    },
+    expectedFormsCount: 2,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "user1",
+    newPasswordFieldValue: "pass1",
+    oldPasswordFieldValue: null,
+  },
+  { // Same as above but with the other form ignored.
+    document: `<input id="u1" value="">
+      <input id="p1" type=password value="" form="form1">
+      <input id="p2" type=password value="">
+      <form id="form1">
+        <input id="u2" value="">
+        <input id="p3" type=password value="">
+      </form>`,
+    selectorValues: {
+      "#u1": "user1",
+      "#p1": "pass2",
+      "#p2": "ignore-form-submission",
+      "#u2": "user3",
+      "#p3": "pass2",
+    },
+
+    expectedFormsCount: 2,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: null,
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: null,
+  },
+  {
+    document: `<!-- recipe field override -->
+      <input name="recipeuname" value="">
+      <input id="u1" value="">
+      <input id="p1" type=password value="">
+      <input name="recipepword" type=password value="">`,
+    selectorValues: {
+      "[name='recipeuname']": "username from recipe",
+      "#u1": "default field username",
+      "#p1": "pass1",
+      "[name='recipepword']": "pass2",
+    },
+
+    expectedFormsCount: 1,
+    origin: DEFAULT_ORIGIN,
+    formActionOrigin: DEFAULT_ORIGIN,
+    usernameFieldValue: "username from recipe",
+    newPasswordFieldValue: "pass2",
+    oldPasswordFieldValue: null,
+  },
+];
+
+function filterFormSubmissions({ origin, data }) {
+  return data.newPasswordField.value != "ignore-form-submission";
+}
+
+async function testFormlesSubmitNavigation(tc, testDoc, scriptName) {
+
+  let loginFrame = document.getElementById("loginFrame");
+  let loadedPromise = new Promise((resolve) => {
+    loginFrame.addEventListener("load", function() {
+      resolve();
+    }, {once: true});
+  });
+  loginFrame.src = DEFAULT_ORIGIN + "/tests/toolkit/components/passwordmgr/test/mochitest/blank.html";
+  await loadedPromise;
+
+  let frameDoc = SpecialPowers.wrap(loginFrame.contentWindow).document;
+
+  let formsProcessed = promiseFormsProcessed(tc.expectedFormsCount);
+  frameDoc.documentElement.innerHTML = testDoc;
+  await formsProcessed;
+  // We eliminate no user input as a reason for not capturing by modifying the value
+  setUserInputValues(frameDoc.documentElement, tc.selectorValues)
+
+  let submitProcessed = getSubmitMessage(filterFormSubmissions);
+  info("Running " + scriptName + " script to cause a submission");
+  frameDoc.defaultView.eval(SCRIPTS[scriptName]);
+
+  info("Waiting for formSubmissionProcsssed message");
+  let { origin, data } = await submitProcessed;
+  info("Got for formSubmissionProcsssed message");
+
+  // Check data sent via PasswordManager:onFormSubmit
+  is(origin, tc.origin, "Check origin");
+  is(data.formActionOrigin, tc.formActionOrigin, "Check formActionOrigin");
+
+  if (tc.usernameFieldValue === null) {
+    is(data.usernameField, tc.usernameFieldValue, "Check usernameField");
+  } else {
+    is(data.usernameField.value, tc.usernameFieldValue, "Check usernameField");
+  }
+
+  is(data.newPasswordField.value, tc.newPasswordFieldValue, "Check newPasswordFieldValue");
+
+  if (tc.oldPasswordFieldValue === null) {
+    is(data.oldPasswordField, tc.oldPasswordFieldValue, "Check oldPasswordFieldValue");
+  } else {
+    is(data.oldPasswordField.value, tc.oldPasswordFieldValue, "Check oldPasswordFieldValue");
+  }
+};
+
+let count = 0;
+for (let tc of TESTCASES) {
+  for (let scriptName of Object.keys(SCRIPTS)) {
+    for (let surroundDocumentWithForm of [false, true]) {
+      let testDoc = tc.document;
+      if (surroundDocumentWithForm) {
+        if (testDoc.includes("<form")) {
+          info("Skipping surroundDocumentWithForm case since document already contains a <form>");
+          continue;
+        }
+        testDoc = "<form>" + testDoc + "</form>";
+      }
+      let taskName = `testcase-${count}-${scriptName}${surroundDocumentWithForm ? '-formWrapped' : ''}`;
+      let tmp = {
+        async [taskName]() {
+          info("Starting testcase with script " + scriptName + " and " +
+               (surroundDocumentWithForm ? "a" : "no") + " form wrapper: " + JSON.stringify(tc));
+          await testFormlesSubmitNavigation(tc, testDoc, scriptName);
+        },
+      };
+      add_task(tmp[taskName]);
+    }
+  }
+  count++;
+}
+
+</script>
+
+<p id="display"></p>
+
+<div id="content">
+  <iframe id="loginFrame" src="http://test1.mochi.test:8888/tests/toolkit/components/passwordmgr/test/mochitest/blank.html"></iframe>
+</div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_navigation_negative.html b/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_navigation_negative.html
new file mode 100644
index 0000000000..338cd5d2c1
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_navigation_negative.html
@@ -0,0 +1,148 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test no capturing of fields outside of a form due to navigation</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script type="application/javascript">
+SimpleTest.requestFlakyTimeout("Testing that a message doesn't arrive");
+
+let loadPromise = new Promise(resolve => {
+  document.addEventListener("DOMContentLoaded", () => {
+    document.getElementById("loginFrame").addEventListener("load", (evt) => {
+      resolve();
+    });
+  });
+});
+
+function submissionProcessed(...args) {
+  ok(false, "No formSubmissionProcessed should occur in this test");
+  info("got: " + JSON.stringify(args));
+}
+
+add_setup(async () => {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["signon.formlessCapture.enabled", true],
+    ],
+  });
+
+  info("Waiting for page and frame loads");
+  await loadPromise;
+
+  PWMGR_COMMON_PARENT.addMessageListener("formSubmissionProcessed", submissionProcessed);
+
+  SimpleTest.registerCleanupFunction(() => {
+    PWMGR_COMMON_PARENT.removeMessageListener("formSubmissionProcessed", submissionProcessed);
+  });
+});
+
+const DEFAULT_ORIGIN = "http://test1.mochi.test:8888";
+const SCRIPTS = {
+  PUSHSTATE: `history.pushState({}, "Pushed state", "?pushed");`,
+  WINDOW_LOCATION: `window.location = "data:text/html;charset=utf-8,window.location";`,
+  WINDOW_LOCATION_RELOAD: `window.location.reload();`,
+  HISTORY_BACK: `history.back();`,
+  HISTORY_GO_MINUS1: `history.go(-1);`,
+};
+const TESTCASES = [
+  // Begin test cases that shouldn't trigger capture.
+  {
+    // Empty password field in a form
+    document: `<form><input type=password value="xxx"></form>`,
+    selectorValues: {
+      "[type=password]": "",
+    },
+  },
+  {
+    // Empty password field
+    document: `<input type=password value="">`,
+    selectorValues: {
+      "[type=password]": "",
+    },
+  },
+  {
+    // Test with an input that would normally be captured but with SCRIPTS that
+    // shouldn't trigger capture.
+    document: `<input type=password value="">`,
+    selectorValues: {
+      "[type=password]": "pass2",
+    },
+    wouldCapture: true,
+  },
+  {
+    // Test with an input that would normally be captured but with SCRIPTS that
+    // shouldn't trigger capture.
+    document: `<form><input type=password value=""></form>`,
+    selectorValues: {
+      "[type=password]": "pass2",
+    },
+    wouldCapture: true,
+  },
+];
+
+async function testFormlesSubmitNavigationNegative(tc, scriptName) {
+  let loginFrame = document.getElementById("loginFrame");
+  let waitTime;
+  let android = navigator.appVersion.includes("Android");
+  if (android) {
+    // intermittent failures on Android Debug at 5 seconds
+    waitTime = 10000;
+  } else {
+    waitTime = 5000;
+  }
+
+  let loadedPromise = new Promise((resolve) => {
+    loginFrame.addEventListener("load", function() {
+      resolve();
+    }, {once: true});
+  });
+  loginFrame.src = DEFAULT_ORIGIN + "/tests/toolkit/components/passwordmgr/test/mochitest/blank.html";
+  await loadedPromise;
+
+  let frameDoc = SpecialPowers.wrap(loginFrame.contentWindow).document;
+  frameDoc.documentElement.innerHTML = tc.document;
+  // We eliminate no user input as a reason for not capturing by modifying the value
+  setUserInputValues(frameDoc.documentElement, tc.selectorValues);
+
+  info("Running " + scriptName + " script to check for a submission");
+  frameDoc.defaultView.eval(SCRIPTS[scriptName]);
+
+  // Wait to see if the promise above resolves.
+  await new Promise(resolve => setTimeout(resolve, waitTime));
+  ok(true, "Done waiting for captures");
+}
+
+let count = 0;
+for (let tc of TESTCASES) {
+  for (let scriptName of Object.keys(SCRIPTS)) {
+    if (tc.wouldCapture && ["PUSHSTATE", "WINDOW_LOCATION"].includes(scriptName)) {
+      // Don't run scripts that should actually capture for this testcase.
+      continue;
+    }
+    let taskName = `testcase-${count}-${scriptName}`;
+    let tmp = {
+      async [taskName]() {
+        info("Starting testcase with script " + scriptName + ": " + JSON.stringify(tc));
+        await testFormlesSubmitNavigationNegative(tc, scriptName);
+      },
+    };
+    add_task(tmp[taskName]);
+  }
+}
+
+
+</script>
+
+<p id="display"></p>
+
+<div id="content">
+  <iframe id="loginFrame" src="http://test1.mochi.test:8888/tests/toolkit/components/passwordmgr/test/mochitest/blank.html"></iframe>
+</div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_include_other_subdomains_in_lookup.html b/toolkit/components/passwordmgr/test/mochitest/test_include_other_subdomains_in_lookup.html
new file mode 100644
index 0000000000..4c569463c5
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_include_other_subdomains_in_lookup.html
@@ -0,0 +1,202 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test includeOtherSubdomainsInLookup</title>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+  Test that logins with non-exact match origin appear in autocomplete dropdown.
+
+  The includeOtherSubdomainsInLookup feature offers autocomplete results for
+  subdomain related logins.
+
+  For this testcase, there exists two logins for this origin on different
+  subdomains (old.example.com and new.example.com) but with different
+  passwords, beneath one login for the parent domain (example.com). Both
+  logins should appear in the autocomplete popup.
+
+<template id="form1-template">
+  <form id="form1" action="https://otherexample.com/formtest.js">
+    <input type="text" name="uname">
+    <input type="password" name="pword">
+  </form>
+</template>
+
+<script class="testbody" type="text/javascript">
+  const formTemplate = document.getElementById("form1-template");
+
+  const domainname = location.hostname;
+  const loginInfos = [
+    [`https://${domainname}/`, `https://${domainname}/`, null, "example-user", "example-password", "uname", "pword"],
+    [`https://old.${domainname}/`, `https://old.${domainname}/`, null, "example-user", "example-password", "uname", "pword"],
+    [`https://new.${domainname}/`, `https://new.${domainname}/`, null, "example-user", "new-example-password", "uname", "pword"],
+  ];
+
+  // calculates a date representation as used in the autocomplete menu to
+  // distinguish duplicate logins
+  function getDateString() {
+    const dateAndTimeFormatter = new Services.intl.DateTimeFormat(undefined, { dateStyle: "medium" });
+    return dateAndTimeFormatter.format(new Date());
+  }
+
+  add_setup(async () => {
+    listenForUnexpectedPopupShown();
+  });
+
+  add_named_task("not including https login when includeOtherSubdomainsInLookup is false", async () => {
+    await setPreferencesForTask(["signon.includeOtherSubdomainsInLookup", false]);
+    await setStoredLoginsDuringTask(
+      [`https://${domainname}/`, `https://${domainname}/`, null, "example-user-https", "example-password", "uname", "pword"],
+    );
+    const form = setContentForTask(formTemplate);
+    form.uname.focus();
+
+    await noPopupByArrowDown();
+    ok(true, "no popup has been opened")
+  });
+
+  add_named_task("including https login when includeOtherSubdomainsInLookup is true", async () => {
+    await setPreferencesForTask(["signon.includeOtherSubdomainsInLookup", true]);
+    await setStoredLoginsDuringTask(
+      [`https://${domainname}/`, `https://${domainname}/`, null, "example-user-https", "example-password", "uname", "pword"],
+    );
+    const form = setContentForTask(formTemplate);
+    form.uname.focus();
+
+    const autocompleteItems = await popupByArrowDown();
+    checkAutoCompleteResults(autocompleteItems, ["example-user-https"], window.location.host, "https login showed");
+  });
+
+  add_named_task("including http login when includeOtherSubdomainsInLookup is false", async () => {
+    await setPreferencesForTask(["signon.includeOtherSubdomainsInLookup", false]);
+    await setStoredLoginsDuringTask(
+      // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+      [`http://${domainname}/`, `https://${domainname}/`, null, "example-user-http", "example-password", "uname", "pword"],
+    );
+    const form = setContentForTask(formTemplate);
+    form.uname.focus();
+
+    const autocompleteItems = await popupByArrowDown();
+    checkAutoCompleteResults(autocompleteItems, ["example-user-http"], window.location.host, "http login showed");
+  });
+
+  add_named_task("including http login when includeOtherSubdomainsInLookup is true", async () => {
+    await setPreferencesForTask(["signon.includeOtherSubdomainsInLookup", true]);
+    await setStoredLoginsDuringTask(
+      // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+      [`http://${domainname}/`, `https://${domainname}/`, null, "example-user-http", "example-password", "uname", "pword"],
+    );
+    const form = setContentForTask(formTemplate);
+    form.uname.focus();
+
+    const autocompleteItems = await popupByArrowDown();
+    checkAutoCompleteResults(autocompleteItems, ["example-user-http"], window.location.host, "http login showed");
+  });
+
+  add_named_task("including https and http login when includeOtherSubdomainsInLookup is false", async () => {
+    await setPreferencesForTask(["signon.includeOtherSubdomainsInLookup", false]);
+    await setStoredLoginsDuringTask(
+      [`https://${domainname}/`, `https://${domainname}/`, null, "example-user-https", "example-password", "uname", "pword"],
+      // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+      [`http://${domainname}/`, `https://${domainname}/`, null, "example-user-http", "example-password", "uname", "pword"],
+    );
+    const form = setContentForTask(formTemplate);
+    form.uname.focus();
+
+    const autocompleteItems = await popupByArrowDown();
+    // checkAutoCompleteResults(autocompleteItems, ["example-user-https"], window.location.host, "https login showed");
+    checkAutoCompleteResults(autocompleteItems, ["example-user-http"], window.location.host, "https login showed");
+  });
+
+  add_named_task("including https and http login when includeOtherSubdomainsInLookup is true", async () => {
+    await setPreferencesForTask(["signon.includeOtherSubdomainsInLookup", true]);
+    await setStoredLoginsDuringTask(
+      [`https://${domainname}/`, `https://${domainname}/`, null, "example-user-https", "example-password", "uname", "pword"],
+      // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+      [`http://${domainname}/`, `https://${domainname}/`, null, "example-user-http", "example-password", "uname", "pword"],
+    );
+    const form = setContentForTask(formTemplate);
+    form.uname.focus();
+
+    const autocompleteItems = await popupByArrowDown();
+    // checkAutoCompleteResults(autocompleteItems, ["example-user-https"], window.location.host, "https login showed");
+    checkAutoCompleteResults(autocompleteItems, ["example-user-http", "example-user-https"], window.location.host, "http and https logins showed");
+  });
+
+  add_named_task("menu does not show login for different subdomain when includeOtherSubdomainsInLookup is false", async () => {
+    await setPreferencesForTask(["signon.includeOtherSubdomainsInLookup", false]);
+    await setStoredLoginsDuringTask(
+      ...[
+        // These two logins should never be visible on https: versions of
+        // *.example.com since the login is for http: and an https: login exists
+        // for this username.
+        // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+        [`http://${domainname}/`, `https://${domainname}/`, null, "example-user", "example-password", "uname", "pword"],
+        // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+        [`http://old.${domainname}/`, `https://old.${domainname}/`, null, "example-user", "old-example-password", "uname", "pword"],
+        ...loginInfos,
+      ]
+    );
+    const form = setContentForTask(formTemplate);
+
+    form.uname.focus();
+    const autocompleteItems = await popupByArrowDown();
+    checkAutoCompleteResults(autocompleteItems, ["example-user"], window.location.host, "Only exact subdomain showed");
+  });
+
+  add_named_task("menu shows two logins with the same username for different subdomain", async () => {
+    await setStoredLoginsDuringTask(...loginInfos);
+    await setPreferencesForTask(["signon.includeOtherSubdomainsInLookup", true]);
+    const form = setContentForTask(formTemplate);
+
+    // The logins are added "today" and since they are duplicates, the date that they were last
+    // changed will be appended.
+    const dateString = getDateString();
+    const username = `example-user (${dateString})`;
+
+    form.uname.focus();
+    const autocompleteItems = await popupByArrowDown();
+    checkAutoCompleteResults(autocompleteItems, [username, username], window.location.host, "Check all menuitems are displayed correctly.");
+  });
+
+  add_named_task("login with different subdomain is selectable", async () => {
+    await setPreferencesForTask(["signon.includeOtherSubdomainsInLookup", true]);
+    await setStoredLoginsDuringTask(...loginInfos);
+    const form = setContentForTask(formTemplate);
+
+    // consume initial autofill event
+    await formAutofillResult(form.id);
+
+    form.uname.focus();
+
+    // select first item
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+
+    await formAutofillResult(form.id);
+    is(form.uname.value, "example-user", "correct username is set");
+    is(form.pword.value, "example-password", "password matches first login");
+
+    // select second item
+    await popupByArrowDown();
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_ArrowDown");
+    synthesizeKey("KEY_Enter");
+
+    await formAutofillResult(form.id);
+    is(form.uname.value, "example-user", "correct username is set");
+    is(form.pword.value, "new-example-password", "password matches second login");
+  });
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_input_events.html b/toolkit/components/passwordmgr/test/mochitest/test_input_events.html
new file mode 100644
index 0000000000..2560c212d8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_input_events.html
@@ -0,0 +1,56 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for input events in Login Manager</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: input events should fire.
+<p id="display"></p>
+<div id="content" style="display: none"></div>
+<pre id="test"></pre>
+<script>
+  add_setup(async () => {
+    await setStoredLoginsAsync(
+      [location.origin, location.origin, null, "testuser", "testpass", "uname", "pword"]
+    );
+  })
+
+  add_task(async function username_events() {
+    return new Promise(resolve => {
+      let inputFired = false;
+      const form = createLoginForm();
+      form.uname.oninput = e => {
+        is(e.target.value, "testuser", "Should get 'testuser' as value in input event");
+        inputFired = true;
+      };
+      form.uname.onchange = e => {
+        ok(inputFired, "Should get input event before change event for username field.");
+        is(e.target.value, "testuser", "Should get 'testuser' as value in change event");
+        resolve();
+      };
+    })
+  })
+
+  add_task(async function password_events() {
+    return new Promise(resolve => {
+      let inputFired = false;
+      const form = createLoginForm();
+      form.pword.oninput = e => {
+        is(e.target.value, "testpass", "Should get 'testpass' as value in input event");
+        inputFired = true;
+      };
+      form.pword.onchange = e => {
+        ok(inputFired, "Should get input event before change event for password field.");
+        is(e.target.value, "testpass", "Should get 'testpass' as value in change event");
+        resolve();
+      };
+    })
+  })
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_input_events_for_identical_values.html b/toolkit/components/passwordmgr/test/mochitest/test_input_events_for_identical_values.html
new file mode 100644
index 0000000000..c6e378a516
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_input_events_for_identical_values.html
@@ -0,0 +1,52 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for input events in Login Manager when username/password are filled in already</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body onload="onNewEvent(event)">
+Login Manager test: input events should fire.
+
+<script>
+runChecksAfterCommonInit();
+
+SimpleTest.requestFlakyTimeout("untriaged");
+
+/** Test for Login Manager: form fill when form is already filled, should not get input events. **/
+
+var onloadFired = false;
+
+function onNewEvent(e) {
+  console.error("Got " + e.type + " event.");
+  if (e.type == "load") {
+    onloadFired = true;
+    getFormElementByName(1, "uname").focus();
+    sendKey("Tab");
+  } else {
+    ok(false, "Got an input event for " + e.target.name + " field, which shouldn't happen.");
+  }
+}
+</script>
+
+<p id="display"></p>
+
+<div id="content">
+
+  <form id="form1" action="formtest.js">
+    <p>This is form 1.</p>
+    <input  type="text"       name="uname" oninput="onNewEvent(event)" value="testuser">
+    <input  type="password"   name="pword" oninput="onNewEvent(event)" onfocus="setTimeout(function() { SimpleTest.finish() }, 1000);" value="testpass">
+
+    <button type="submit">Submit</button>
+    <button type="reset"> Reset </button>
+  </form>
+
+</div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_insecure_form_field_no_saved_login.html b/toolkit/components/passwordmgr/test/mochitest/test_insecure_form_field_no_saved_login.html
new file mode 100644
index 0000000000..8fcb9df6f6
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_insecure_form_field_no_saved_login.html
@@ -0,0 +1,91 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test basic login, contextual inscure password warning without saved logins</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: contextual inscure password warning without saved logins
+
+<script>
+let chromeScript = runChecksAfterCommonInit();
+</script>
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content">
+
+  <form id="form1" action="http://autocomplete:8888/formtest.js" onsubmit="return false;">
+    <input  type="text"       name="uname">
+    <input  type="password"   name="pword">
+    <button type="submit">Submit</button>
+  </form>
+
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: contextual insecure password warning without saved logins. **/
+
+let uname = getFormElementByName(1, "uname");
+let pword = getFormElementByName(1, "pword");
+
+// Restore the form to the default state.
+function restoreForm() {
+  uname.value = "";
+  pword.value = "";
+  uname.focus();
+}
+
+function spinEventLoop() {
+  return Promise.resolve();
+}
+
+add_setup(async () => {
+  listenForUnexpectedPopupShown();
+});
+
+add_task(async function test_form1_initial_empty() {
+  await SimpleTest.promiseFocus(window);
+
+  // Make sure initial form is empty.
+  checkLoginForm(uname, "", pword, "");
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is initially closed");
+});
+
+add_task(async function test_form1_warning_entry() {
+  await SimpleTest.promiseFocus(window);
+  // Trigger autocomplete popup
+  restoreForm();
+  await popupBy();
+
+  let popupState = await getPopupState();
+  is(popupState.open, true, "Check popup is opened");
+  is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
+
+  let acEvents = await getTelemetryEvents({ process: "parent", filterProps: TelemetryFilterPropsAC, clear: true });
+  is(acEvents.length, 1, "One autocomplete event");
+  checkACTelemetryEvent(acEvents[0], uname, {
+    "hadPrevious": "0",
+    "insecureWarning": "1",
+    "loginsFooter": "1"
+  });
+
+  synthesizeKey("KEY_ArrowDown"); // select insecure warning
+  checkLoginForm(uname, "", pword, ""); // value shouldn't update just by selecting
+  synthesizeKey("KEY_Enter");
+  await spinEventLoop(); // let focus happen
+  checkLoginForm(uname, "", pword, "");
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_maxlength.html b/toolkit/components/passwordmgr/test/mochitest/test_maxlength.html
new file mode 100644
index 0000000000..a61812f6d3
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_maxlength.html
@@ -0,0 +1,144 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for maxlength attributes</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: Bug 391514
+<script>
+gTestDependsOnDeprecatedLogin = true;
+runChecksAfterCommonInit(() => startTest());
+
+let DEFAULT_ORIGIN = window.location.origin;
+</script>
+<p id="display"></p>
+<div id="content" style="display: none">
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/* Test for Login Manager: 391514 (Login Manager gets confused with
+ * password/PIN on usaa.com)
+ */
+
+async function startTest() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <!-- normal form. -->
+    <form id="form1" action="formtest.js">
+      <input  type="text"     name="uname">
+      <input  type="password" name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- limited username -->
+    <form id="form2" action="formtest.js">
+      <input  type="text"     name="uname" maxlength="4">
+      <input  type="password" name="pword">
+    </form>
+
+    <!-- limited password -->
+    <form id="form3" action="formtest.js">
+      <input  type="text"     name="uname">
+      <input  type="password" name="pword" maxlength="4">
+    </form>
+
+    <!-- limited username and password -->
+    <form id="form4" action="formtest.js">
+      <input  type="text"     name="uname" maxlength="4">
+      <input  type="password" name="pword" maxlength="4">
+    </form>
+
+
+    <!-- limited username -->
+    <form id="form5" action="formtest.js">
+      <input  type="text"     name="uname" maxlength="0">
+      <input  type="password" name="pword">
+    </form>
+
+    <!-- limited password -->
+    <form id="form6" action="formtest.js">
+      <input  type="text"     name="uname">
+      <input  type="password" name="pword" maxlength="0">
+    </form>
+
+    <!-- limited username and password -->
+    <form id="form7" action="formtest.js">
+      <input  type="text"     name="uname" maxlength="0">
+      <input  type="password" name="pword" maxlength="0">
+    </form>
+
+
+    <!-- limited, but ok, username -->
+    <form id="form8" action="formtest.js">
+      <input  type="text"     name="uname" maxlength="999">
+      <input  type="password" name="pword">
+    </form>
+
+    <!-- limited, but ok, password -->
+    <form id="form9" action="formtest.js">
+      <input  type="text"     name="uname">
+      <input  type="password" name="pword" maxlength="999">
+    </form>
+
+    <!-- limited, but ok, username and password -->
+    <form id="form10" action="formtest.js">
+      <input  type="text"     name="uname" maxlength="999">
+      <input  type="password" name="pword" maxlength="999">
+    </form>
+
+
+    <!-- limited, but ok, username -->
+    <!-- (note that filled values are exactly 8 characters) -->
+    <form id="form11" action="formtest.js">
+      <input  type="text"     name="uname" maxlength="8">
+      <input  type="password" name="pword">
+    </form>
+
+    <!-- limited, but ok, password -->
+    <!-- (note that filled values are exactly 8 characters) -->
+    <form id="form12" action="formtest.js">
+      <input  type="text"     name="uname">
+      <input  type="password" name="pword" maxlength="8">
+    </form>
+
+    <!-- limited, but ok, username and password -->
+    <!-- (note that filled values are exactly 8 characters) -->
+    <form id="form13" action="formtest.js">
+      <input  type="text"     name="uname" maxlength="8">
+      <input  type="password" name="pword" maxlength="8">
+    </form>`, win, 13);
+
+  var i;
+
+  await checkLoginFormInFrameWithElementValues(win, 1, "testuser", "testpass");
+
+  for (i = 2; i < 8; i++) {
+    await checkLoginFormInFrameWithElementValues(win, i, "", "");
+  }
+
+  for (i = 8; i < 14; i++) {
+    await checkLoginFormInFrameWithElementValues(win, i, "testuser", "testpass");
+  }
+
+  // Note that tests 11-13 are limited to exactly the expected value.
+  // Assert this lest someone change the login we're testing with.
+  await SpecialPowers.spawn(win, [11, 8], (formNum, length) => {
+    let form = this.content.document.getElementById(`form${formNum}`);
+    let field = form.querySelector("[name='uname']");
+    is(field.value.length, length, "asserting test assumption is valid.");
+  });
+
+  SimpleTest.finish();
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_munged_values.html b/toolkit/components/passwordmgr/test/mochitest/test_munged_values.html
new file mode 100644
index 0000000000..d2fdf91d4a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_munged_values.html
@@ -0,0 +1,362 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test handling of possibly-manipulated username values</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script type="application/javascript">
+const DEFAULT_ORIGIN = window.location.origin;
+
+function removeAllUserFacingLoginsInParent() {
+  runInParent(function removeAllUserFacingLogins() {
+    Services.logins.removeAllUserFacingLogins();
+  });
+}
+
+async function add2logins() {
+  removeAllUserFacingLoginsInParent();
+  await addLoginsInParent([DEFAULT_ORIGIN, DEFAULT_ORIGIN, null, "real••••user", "pass1", "", ""], [DEFAULT_ORIGIN, DEFAULT_ORIGIN, null, "user2", "pass2", "", ""]);
+}
+
+async function addSingleLogin() {
+  removeAllUserFacingLoginsInParent();
+  await addLoginsInParent([DEFAULT_ORIGIN, DEFAULT_ORIGIN, null, "real••••user", "pass1", "", ""])
+}
+
+/**
+ *  For any test including the character "!", generate a version of that test for every known munge
+ *  character.
+ **/
+ function generateTestCases(test) {
+  const MUNGE_CHARS = ["*", ".", "•"];
+
+  const nothingToReplace = Object.values(test).every(value => typeof value !== "string" || !value.includes("!"));
+  if (nothingToReplace) {
+    return test;
+  };
+
+  return MUNGE_CHARS.map(char => {
+    const newTest = {};
+    for (const [propName, val] of Object.entries(test)) {
+      if (typeof val === "string") {
+        newTest[propName] = val.replace(/!/g, char);
+      } else {
+        newTest[propName] = val;
+      }
+  };
+  return newTest;
+})};
+
+const loadPromise = new Promise(resolve => {
+  document.addEventListener("DOMContentLoaded", () => {
+    resolve();
+  });
+});
+
+add_setup(async () => {
+  await setStoredLoginsAsync();
+  info("Waiting for page and window loads");
+  await loadPromise;
+});
+
+add_task(async function test_new_logins() {
+  const TEST_CASES = [
+  // ! is replaced with characters commonly used for munging
+  {
+    testName: "test_middle!MaskedUsername",
+    username: "so!!!ne",
+    expected: null,
+  },
+  {
+    testName: "test_start!MaskedUsername",
+    username: "!!!eone",
+    expected: null,
+  },
+  {
+    testName: "test_end!MaskedUsername",
+    username: "some!!!",
+    expected: null,
+  },
+  {
+    testName: "test_ok!Username",
+    username: "obelixand!",
+    expected: "obelixand!",
+  },
+  {
+    testName: "test_ok!Username2",
+    username: "!!username!!",
+    expected: "!!username!!",
+  },
+  {
+    // We should only consider a username munged if it repeats of the same character
+    testName: "test_combinedMungeCharacters",
+    username: "*.•*.•*.•*.•*.•*.•",
+    expected: "*.•*.•*.•*.•*.•*.•",
+  },
+].flatMap(generateTestCases);
+  for (const tc of TEST_CASES) {
+    info("Starting testcase: " + JSON.stringify(tc));
+    // Create a new window for each test case, because if we instead try to use
+    // the same window and change the page using window.location, that will trigger
+    // an onLocationChange event, which can trigger unwanted FormSubmit outside of
+    // clicking the submit button in each test document.
+    const win = window.open("about:blank");
+    const html = `
+      <form id="form1" onsubmit="return false;">
+        <input  type="text"       name="uname" value="${tc.username}">
+        <input  type="password"   name="pword" value="thepassword">
+        <button type="submit" id="submitBtn">Submit</button>
+      </form>`;
+    await loadFormIntoWindow(DEFAULT_ORIGIN, html, win);
+    await SpecialPowers.spawn(win, [html], function(contentHtml) {
+      const doc = this.content.document;
+      for (const field of doc.querySelectorAll("input")) {
+        const actualValue = field.value;
+        field.value = "";
+        SpecialPowers.wrap(field).setUserInput(actualValue);
+      }
+    });
+    await SpecialPowers.spawn(win, [tc], function(testcase) {
+      const doc = this.content.document;
+      Assert.equal(doc.querySelector("[name='uname']").value, testcase.username, "Checking for filled username");
+    });
+
+    // Check data sent via PasswordManager:onFormSubmit
+    const processedPromise = getSubmitMessage();
+    await SpecialPowers.spawn(win, [], function() {
+      this.content.document.getElementById("submitBtn").click();
+    });
+
+    const { data } = await processedPromise;
+    info("Got submitted result: " + JSON.stringify(data));
+
+    if (tc.expected === null) {
+      is(data.usernameField, tc.expected, "Check usernameField");
+    } else {
+      is(data.usernameField.value, tc.expected, "Check usernameField");
+    }
+
+    win.close();
+    await SimpleTest.promiseFocus(window);
+  }
+});
+
+add_task(async function test_no_save_dialog_when_password_is_fully_munged() {
+  const TEST_CASES = [
+  {
+      testName: "test_passFullyMungedBy!",
+      password: "!!!!!!!!!",
+      shouldShowPrompt: false,
+    },
+    {
+      testName: "test_passStartsMungedBy!",
+      password: "!!!!!!!butThenAPassword",
+      shouldShowPrompt: true,
+    },
+    {
+      testName: "test_passEndsMungedBy!",
+      password: "aRealPasswordAndThen!!!!!!!",
+      shouldShowPrompt: true,
+    },
+    {
+      testName: "test_passMostlyMungedBy!",
+      password: "!!!a!!!!",
+      shouldShowPrompt: true,
+    },
+    {
+      testName: "test_combinedMungedCharacters",
+      password: "*.•*.•*.•*.•",
+      shouldShowPrompt: true,
+    },
+  ].flatMap(generateTestCases);
+
+  for (const tc of TEST_CASES) {
+    info("Starting testcase: " + tc.testName)
+    // Create a new window for each test case, because if we instead try to use
+    // the same window and change the page using window.location, that will trigger
+    // an onLocationChange event, which can trigger unwanted FormSubmit outside of
+    // clicking the submit button in each test document.
+    const win = window.open("about:blank");
+    const html = `
+      <form id="form1" onsubmit="return false;">
+        <input  type="text"       name="uname" value="username">
+        <input  type="password"   name="pword" value="${tc.password}">
+        <button type="submit" id="submitBtn">Submit</button>
+      </form>`;
+    await loadFormIntoWindow(DEFAULT_ORIGIN, html, win);
+    await SpecialPowers.spawn(win, [html], function(contentHtml) {
+      const doc = this.content.document;
+      for (const field of doc.querySelectorAll("input")) {
+        const actualValue = field.value;
+        field.value = "";
+        SpecialPowers.wrap(field).setUserInput(actualValue);
+      }
+    });
+    await SpecialPowers.spawn(win, [tc], function(testcase) {
+      const doc = this.content.document;
+      Assert.equal(doc.querySelector("[name='pword']").value, testcase.password, "Checking for filled password");
+    });
+
+    const formSubmitListener = SpecialPowers.spawn(win, [], function() {
+      return new Promise(resolve => {
+        this.content.windowRoot.addEventListener(
+            "PasswordManager:ShowDoorhanger",
+            event => {
+              info(`PasswordManager:ShowDoorhanger called. Event: ${JSON.stringify(event)}`);
+              resolve(event.detail.messageSent);
+            }
+          );
+      });
+    });
+
+    await SpecialPowers.spawn(win, [], function() {
+      this.content.document.getElementById("submitBtn").click();
+    });
+
+    const dialogRequested = await formSubmitListener;
+
+    is(dialogRequested, tc.shouldShowPrompt, "Verify 'show save/update prompt' message sent to parent process");
+
+    win.close();
+    await SimpleTest.promiseFocus(window);
+  }
+});
+
+add_task(async function test_no_autofill_munged_username_matching_password() {
+  // run this test with 2 matching logins from this origin so we don't autofill
+  await add2logins();
+  const allLogins = await LoginManager.getAllLogins();
+  const matchingLogins = Array.prototype.filter.call(allLogins, l => l.origin == DEFAULT_ORIGIN);
+  is(matchingLogins.length, 2, "Expected number of matching logins");
+
+  const bulletLogin = matchingLogins.find(l => l.username == "real••••user");
+  ok(bulletLogin, "Found the real••••user login");
+
+  const timesUsed = bulletLogin.timesUsed;
+  const guid = bulletLogin.guid;
+
+  const win = window.open("about:blank");
+  const html =
+    `<form id="form1" onsubmit="return false;">
+      <input  type="text"       name="uname" value="">
+      <input  type="password"   name="pword" value="">
+      <button type="submit" id="submitBtn">Submit</button>
+    </form>`;
+  await loadFormIntoWindow(DEFAULT_ORIGIN, html, win);
+  await SpecialPowers.spawn(win, [html], function(contentHtml) {
+    const doc = this.content.document;
+    for (const field of doc.querySelectorAll("input")) {
+      const actualValue = field.value;
+      field.value = "";
+      SpecialPowers.wrap(field).setUserInput(actualValue);
+    }
+  });
+  await SpecialPowers.spawn(win, [], function() {
+    const doc = this.content.document;
+    Assert.equal(doc.querySelector("[name='uname']").value, "", "Check username didn't get autofilled");
+    SpecialPowers.wrap(doc.querySelector("[name='uname']")).setUserInput("real••••user");
+    SpecialPowers.wrap(doc.querySelector("[name='pword']")).setUserInput("pass1");
+  });
+
+  // we shouldn't get the save password doorhanger...
+  const popupShownPromise = noPopupBy();
+
+  // Check data sent via PasswordManager:onFormSubmit
+  const processedPromise = getSubmitMessage();
+  await SpecialPowers.spawn(win, [], function() {
+    this.content.document.getElementById("submitBtn").click();
+  });
+
+  const { data } = await processedPromise;
+  info("Got submitted result: " + JSON.stringify(data));
+
+  is(data.usernameField, null, "Check usernameField");
+
+  const updatedLogins = await LoginManager.getAllLogins();
+  const updatedLogin = Array.prototype.find.call(updatedLogins, l => l.guid == guid);
+  ok(updatedLogin, "Got the login via guid");
+  is(updatedLogin.timesUsed, timesUsed + 1, "timesUsed was incremented");
+
+  await popupShownPromise;
+
+  win.close();
+  await SimpleTest.promiseFocus(window);
+});
+
+
+add_task(async function test_autofill_munged_username_matching_password() {
+  // only a single matching login so we autofill the username
+  await addSingleLogin();
+
+  const allLogins = await LoginManager.getAllLogins();
+  const matchingLogins = Array.prototype.filter.call(allLogins, l => l.origin == DEFAULT_ORIGIN);
+  is(matchingLogins.length, 1, "Expected number of matching logins");
+
+  info("matched login: " + matchingLogins[0].username);
+  const bulletLogin = matchingLogins.find(l => l.username == "real••••user");
+  ok(bulletLogin, "Found the real••••user login");
+
+  const timesUsed = bulletLogin.timesUsed;
+  const guid = bulletLogin.guid;
+
+  const win = window.open("about:blank");
+  const html =
+    `<form id="form1" onsubmit="return false;">
+      <input  type="text"       name="uname" value="">
+      <input  type="password"   name="pword" value="">
+      <button type="submit" id="submitBtn">Submit</button>
+    </form>`;
+  await loadFormIntoWindow(DEFAULT_ORIGIN, html, win);
+  await SpecialPowers.spawn(win, [html], function(contentHtml) {
+    const doc = this.content.document;
+    for (const field of doc.querySelectorAll("input")) {
+      const actualValue = field.value;
+      field.value = "";
+      SpecialPowers.wrap(field).setUserInput(actualValue);
+    }
+  });
+  await SpecialPowers.spawn(win, [], function() {
+    const doc = this.content.document;
+    Assert.equal(doc.querySelector("[name='uname']").value, "real••••user", "Check username did get autofilled");
+    doc.querySelector("[name='pword']").setUserInput("pass1");
+  });
+
+  // we shouldn't get the save/update password doorhanger as it didn't change
+  const popupShownPromise = noPopupBy();
+
+  // Check data sent via PasswordManager:onFormSubmit
+  const processedPromise = getSubmitMessage();
+  await SpecialPowers.spawn(win, [], function() {
+    this.content.document.getElementById("submitBtn").click();
+  });
+
+  const { data } = await processedPromise;
+  info("Got submitted result: " + JSON.stringify(data));
+
+  is(data.usernameField, null, "Check usernameField");
+
+  const updatedLogins = await LoginManager.getAllLogins();
+  const updatedLogin = Array.prototype.find.call(updatedLogins, l => l.guid == guid);
+  ok(updatedLogin, "Got the login via guid");
+  is(updatedLogin.timesUsed, timesUsed + 1, "timesUsed was incremented");
+
+  await popupShownPromise;
+
+  win.close();
+  await SimpleTest.promiseFocus(window);
+});
+
+</script>
+
+<p id="display"></p>
+
+<div id="content">
+</div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_one_doorhanger_per_un_pw.html b/toolkit/components/passwordmgr/test/mochitest/test_one_doorhanger_per_un_pw.html
new file mode 100644
index 0000000000..4d8dfd1fee
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_one_doorhanger_per_un_pw.html
@@ -0,0 +1,59 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Don't repeatedly prompt to save the same username and password
+    combination in the same document</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script>
+  let chromeScript = runChecksAfterCommonInit();
+
+  SimpleTest.requestFlakyTimeout("Giving a chance for the unexpected popupshown to occur");
+</script>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+   <form id="form1" onsubmit="return false;">
+    <input  type="text"     name="uname" id="ufield">
+    <input  type="password" name="pword" id="pfield">
+    <button type="submit" id="submitBtn">Submit</button>
+   </form>
+</div>
+
+<pre id="test"></pre>
+<script>
+  /** Test for Login Manager: Don't repeatedly prompt to save the
+      same username and password combination in the same document **/
+
+  add_task(async function test_prompt_does_not_reappear() {
+    let username = document.getElementById("ufield");
+    let password = document.getElementById("pfield");
+    let submitButton = document.getElementById("submitBtn");
+
+    SpecialPowers.wrap(username).setUserInput("user");
+    SpecialPowers.wrap(password).setUserInput("pass");
+
+    let processedPromise = getSubmitMessage();
+    let promptShownPromise = promisePromptShown("passwordmgr-prompt-save");
+    submitButton.click();
+    await processedPromise;
+    await promptShownPromise;
+
+    is(username.value, "user", "Checking for filled username");
+    is(password.value, "pass", "Checking for filled password");
+
+    let promptShown = false;
+    promptShownPromise = promisePromptShown("passwordmgr-prompt-save").then(value => {
+      promptShown = true;
+    });
+    submitButton.click();
+    await new Promise(resolve => setTimeout(resolve, 1000));
+    ok(!promptShown, "Prompt is not shown for the same login values a second time");
+  });
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_onsubmit_value_change.html b/toolkit/components/passwordmgr/test/mochitest/test_onsubmit_value_change.html
new file mode 100644
index 0000000000..18b851c86f
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_onsubmit_value_change.html
@@ -0,0 +1,71 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test input value change right after onsubmit event</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: input value change right after onsubmit event
+
+<script>
+  let chromeScriptPromise = runChecksAfterCommonInit();
+
+  async function getSubmitMessage() {
+    info("getSubmitMessage");
+    let chromeScript = await chromeScriptPromise;
+    return new Promise(resolve => {
+      chromeScript.addMessageListener("formSubmissionProcessed", function processed(...args) {
+        info("got formSubmissionProcessed");
+        chromeScript.removeMessageListener("formSubmissionProcessed", processed);
+        resolve(args[0]);
+      });
+    });
+  }
+</script>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+
+  <form id="form1" action="formTest.js" onsubmit="return false;">
+    <input  type="text"     name="uname" id="ufield">
+    <input  type="password" name="pword" id="pfield">
+    <button type="submit" id="submitBtn">Submit</button>
+  </form>
+
+</div>
+
+<pre id="test"></pre>
+<script>
+  /** Test for Login Manager: input value change right after onsubmit event **/
+  add_task(async function checkFormValues() {
+    SpecialPowers.wrap(document.getElementById("ufield")).setUserInput("testuser");
+    SpecialPowers.wrap(document.getElementById("pfield")).setUserInput("testpass");
+    is(getFormElementByName(1, "uname").value, "testuser", "Checking for filled username");
+    is(getFormElementByName(1, "pword").value, "testpass", "Checking for filled password");
+
+    document.getElementById("form1").addEventListener("submit", () => {
+      // deliberately assign to .value rather than setUserInput:
+      // the scenario under test here is that script is changing/populating
+      // fields after the user has clicked the submit button
+      document.getElementById("ufield").value = "newuser";
+      document.getElementById("pfield").value = "newpass";
+    }, true);
+
+    document.getElementById("form1").addEventListener("submit", (e) => e.preventDefault());
+
+    let processedPromise = getSubmitMessage();
+
+    let button = document.getElementById("submitBtn");
+    button.click();
+
+    let { data } = await processedPromise;
+    is(data.usernameField.value, "testuser", "Should have registered \"testuser\" for username");
+    is(data.newPasswordField.value, "testpass", "Should have registered \"testpass\" for username");
+  });
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_password_field_autocomplete.html b/toolkit/components/passwordmgr/test/mochitest/test_password_field_autocomplete.html
new file mode 100644
index 0000000000..cb7f759cab
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_password_field_autocomplete.html
@@ -0,0 +1,185 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test basic login autocomplete</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: multiple login autocomplete
+<p id="display"></p>
+
+<!-- we presumably can't hide the content for this test. -->
+<div id="content"></div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+/** Test for Login Manager: multiple login autocomplete. **/
+
+const INSECURE_WARNING_TEXT = "This connection is not secure. Logins entered here could be compromised. Learn More";
+
+// Restore the form to the default state.
+async function reinitializeForm(index) {
+  // Using innerHTML is for creating the autocomplete popup again, so the
+  // preference value will be applied to the constructor of
+  // LoginAutoCompleteResult.
+  let form = document.getElementById("form" + index);
+  let temp = form.innerHTML;
+  form.innerHTML = "";
+  form.innerHTML = temp;
+
+  await new Promise(resolve => {
+    let observer = SpecialPowers.wrapCallback(() => {
+      SpecialPowers.removeObserver(observer, "passwordmgr-processed-form");
+      resolve();
+    });
+    SpecialPowers.addObserver(observer, "passwordmgr-processed-form");
+  });
+
+  await SimpleTest.promiseFocus(window);
+
+  const uname = getFormElementByName(index, "uname");
+  const pword = getFormElementByName(index, "pword");
+  uname.value = "";
+  pword.value = "";
+  pword.focus();
+}
+
+function generateDateString(date) {
+  let dateAndTimeFormatter = new Services.intl.DateTimeFormat(undefined,
+                                                              { dateStyle: "medium" });
+  return dateAndTimeFormatter.format(date);
+}
+
+const DATE_NOW_STRING = generateDateString(new Date());
+
+// Check for expected username/password in form.
+function checkACFormPasswordField(expectedPassword) {
+  const pword = getFormElementByName(1, "pword");
+  is(pword.value, expectedPassword, "Checking form1 password is: " + JSON.stringify(expectedPassword));
+}
+
+async function userOpenAutocompleteOnForm1(autoFillInsecureForms) {
+  await SpecialPowers.pushPrefEnv({"set": [
+    ["signon.autofillForms.http", autoFillInsecureForms],
+  ]});
+  await reinitializeForm(1);
+  const autocompleteItems = await popupBy();
+
+  const popupState = await getPopupState();
+  is(popupState.selectedIndex, -1, "Check no entries are selected upon opening");
+
+  const expectedMenuItems = [INSECURE_WARNING_TEXT,
+                           "No username (" + DATE_NOW_STRING + ")",
+                           "tempuser1",
+                           "testuser2",
+                           "testuser3",
+                           "zzzuser4"];
+  checkAutoCompleteResults(autocompleteItems, expectedMenuItems, "mochi.test", "Check all menuitems are displayed correctly.");
+}
+
+async function userPressedDown_passwordIs(value) {
+  synthesizeKey("KEY_ArrowDown");
+  await Promise.resolve(); // let focus happen
+  checkACFormPasswordField(value);
+}
+
+async function userPressedEnter_passwordIs(value) {
+  synthesizeKey("KEY_Enter");
+  await Promise.resolve(); // let focus happen
+  checkACFormPasswordField(value);
+}
+
+async function noPopupOnForm(formIndex, reason) {
+  await SpecialPowers.pushPrefEnv({"set": [
+    ["signon.autofillForms.http", true],
+  ]});
+  await reinitializeForm(formIndex);
+
+  // Trigger autocomplete popup
+  synthesizeKey("KEY_ArrowDown"); // open
+  let popupState = await getPopupState();
+  is(popupState.open, false, reason);
+}
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    // login0 has no username, so should be filtered out from the autocomplete list.
+    [location.origin, "http://autocomplete:8888", null, "", "user0pass", "", "pword"],
+    [location.origin, "http://autocomplete:8888", null, "tempuser1", "temppass1", "uname", "pword"],
+    [location.origin, "http://autocomplete:8888", null, "testuser2", "testpass2", "uname", "pword"],
+    [location.origin, "http://autocomplete:8888", null, "testuser3", "testpass3", "uname", "pword"],
+    [location.origin, "http://autocomplete:8888", null, "zzzuser4", "zzzpass4", "uname", "pword"]
+  );
+  createLoginForm({
+    num: 1,
+    action: "http://autocomplete:8888/formtest.js"
+  });
+  createLoginForm({
+    num: 2,
+    actio: "http://autocomplete:8888/formtest.js",
+    password: {
+      readonly: true
+    }
+  });
+  createLoginForm({
+    num: 3,
+    action: "http://autocomplete:8888/formtest.js",
+    password: {
+      disabled: true
+    }
+  });
+  listenForUnexpectedPopupShown();
+});
+
+add_task(async function form1_initial_empty() {
+  await SimpleTest.promiseFocus(window);
+
+  // Make sure initial form is empty.
+  checkACFormPasswordField("");
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is initially closed");
+});
+
+add_task(async function noAutocompleteForReadonlyField() {
+  await noPopupOnForm(2, "Check popup is closed for a readonly field.");
+});
+
+add_task(async function noAutocompleteForDisabledField() {
+  await noPopupOnForm(3, "Check popup is closed for a disabled field.");
+});
+
+add_task(async function insecureAutoFill_EnterOnWarning() {
+  await userOpenAutocompleteOnForm1(true);
+  await userPressedDown_passwordIs("");
+  await userPressedEnter_passwordIs("");
+});
+
+add_task(async function insecureAutoFill_EnterOnLogin() {
+  await userOpenAutocompleteOnForm1(true);
+  await userPressedDown_passwordIs(""); // select insecure warning
+  await userPressedDown_passwordIs(""); // select login
+  await userPressedEnter_passwordIs("user0pass");
+});
+
+add_task(async function noInsecureAutoFill_EnterOnWarning() {
+  await userOpenAutocompleteOnForm1(false);
+  await userPressedDown_passwordIs(""); // select insecure warning
+  await userPressedEnter_passwordIs("");
+});
+
+add_task(async function noInsecureAutoFill_EnterOnLogin() {
+  await userOpenAutocompleteOnForm1(false);
+  await userPressedDown_passwordIs(""); // select insecure warning
+  await userPressedDown_passwordIs(""); // select login
+  await userPressedEnter_passwordIs("user0pass");
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_password_length.html b/toolkit/components/passwordmgr/test/mochitest/test_password_length.html
new file mode 100644
index 0000000000..724caf236f
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_password_length.html
@@ -0,0 +1,145 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test handling of different password length</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script type="application/javascript">
+let readyPromise = registerRunTests();
+
+let loadPromise = new Promise(resolve => {
+  document.addEventListener("DOMContentLoaded", () => {
+    document.getElementById("loginFrame").addEventListener("load", (evt) => {
+      resolve();
+    });
+  });
+});
+
+async function loadFormIntoIframe(origin, html) {
+  let loginFrame = document.getElementById("loginFrame");
+  let loadedPromise = new Promise((resolve) => {
+    loginFrame.addEventListener("load", function() {
+      resolve();
+    }, {once: true});
+  });
+  let processedPromise = promiseFormsProcessed();
+  loginFrame.src = origin + "/tests/toolkit/components/passwordmgr/test/mochitest/blank.html";
+  await loadedPromise;
+
+  await SpecialPowers.spawn(getIframeBrowsingContext(window, 0), [html], function(contentHtml) {
+    this.content.document.documentElement.innerHTML = contentHtml;
+  });
+
+  // Wait for the form to be processed before trying to submit.
+  await processedPromise;
+}
+
+add_setup(async () => {
+  info("Waiting for setup and page and frame loads");
+  await readyPromise;
+  await loadPromise;
+});
+
+const DEFAULT_ORIGIN = window.location.origin;
+const TESTCASES = [
+  {
+    testName: "test_control2PasswordFields",
+    pword1: "pass1",
+    pword2: "pass2",
+    expectedNewPassword: { value: "pass2" },
+    expectedOldPassword: { value: "pass1" },
+  },
+  {
+    testName: "test_1characterPassword",
+    pword1: "x",
+    pword2: "pass2",
+    expectedNewPassword: { value: "pass2" },
+    expectedOldPassword: null,
+  },
+  {
+    testName: "test_2characterPassword",
+    pword1: "xy",
+    pword2: "pass2",
+    expectedNewPassword: { value: "pass2" },
+    expectedOldPassword: { value: "xy" },
+  },
+  {
+    testName: "test_1characterNewPassword",
+    pword1: "pass1",
+    pword2: "x",
+    expectedNewPassword: { value: "pass1" },
+    expectedOldPassword: null,
+  },
+];
+
+/**
+ * @return {Promise} resolving when form submission was processed.
+ */
+function getSubmitMessage() {
+  return new Promise((resolve, reject) => {
+    PWMGR_COMMON_PARENT.addMessageListener("formSubmissionProcessed", function processed(...args) {
+      info("got formSubmissionProcessed");
+      PWMGR_COMMON_PARENT.removeMessageListener("formSubmissionProcessed", processed);
+      resolve(args[0]);
+    });
+  });
+}
+
+add_task(async function test_password_lengths() {
+  for (let tc of TESTCASES) {
+    info("Starting testcase: " + tc.testName + ", " + JSON.stringify([tc.pword1, tc.pword2]));
+    await loadFormIntoIframe(DEFAULT_ORIGIN, `<form id="form1" onsubmit="return false;">
+      <input  type="text"       name="uname" value="myname">
+      <input  type="password"   name="pword1" value="">
+      <input  type="password"   name="pword2" value="">
+      <button type="submit" id="submitBtn">Submit</button>
+    </form>`);
+
+    await SpecialPowers.spawn(getIframeBrowsingContext(window, 0), [tc], function(testcase) {
+      let doc = this.content.document;
+      Assert.equal(doc.querySelector("[name='uname']").value, "myname", "Checking for filled username");
+      doc.querySelector("[name='pword1']").setUserInput(testcase.pword1);
+      doc.querySelector("[name='pword2']").setUserInput(testcase.pword2);
+    });
+
+    // Check data sent via PasswordManager:onFormSubmit
+    let processedPromise = getSubmitMessage();
+    await SpecialPowers.spawn(getIframeBrowsingContext(window, 0), [], function() {
+      this.content.document.getElementById("submitBtn").click();
+    });
+
+    let { data } = await processedPromise;
+    info("Got submitted result: " + JSON.stringify(data));
+
+    if (tc.expectedNewPassword === null) {
+      is(data.newPasswordField,
+         tc.expectedNewPassword, "Check expectedNewPassword is null");
+    } else {
+      is(data.newPasswordField.value,
+         tc.expectedNewPassword.value,
+         "Check that newPasswordField.value matches the expectedNewPassword.value");
+    }
+    if (tc.expectedOldPassword === null) {
+      is(data.oldPasswordField,
+         tc.expectedOldPassword, "Check expectedOldPassword is null");
+    } else {
+      is(data.oldPasswordField.value,
+         tc.expectedOldPassword.value,
+         "Check that oldPasswordField.value matches expectedOldPassword.value");
+    }
+  }
+});
+</script>
+
+<p id="display"></p>
+
+<div id="content">
+  <iframe id="loginFrame" src="/tests/toolkit/components/passwordmgr/test/mochitest/blank.html"></iframe>
+</div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_passwords_in_type_password.html b/toolkit/components/passwordmgr/test/mochitest/test_passwords_in_type_password.html
new file mode 100644
index 0000000000..fcaeb0e455
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_passwords_in_type_password.html
@@ -0,0 +1,114 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test that passwords only get filled in type=password</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: Bug 242956
+<script>
+gTestDependsOnDeprecatedLogin = true;
+runChecksAfterCommonInit(() => startTest());
+
+let DEFAULT_ORIGIN = window.location.origin;
+</script>
+<p id="display"></p>
+<div id="content" style="display: none">
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: 242956 (Stored password is inserted into a
+    readable text input on a second page) **/
+
+// Make sure that pwmgr only puts passwords into type=password <input>s.
+// Might as well test the converse, too (username in password field).
+
+async function startTest() {
+  let win = window.open("about:blank");
+  SimpleTest.registerCleanupFunction(() => win.close());
+
+  // only 4 out of 7 forms are to be autofilled
+  await loadFormIntoWindow(DEFAULT_ORIGIN, `
+    <!-- pword is not a type=password input -->
+    <form id="form1" action="formtest.js">
+      <input  type="text" name="uname">
+      <input  type="text" name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- uname is not a type=text input -->
+    <form id="form2" action="formtest.js">
+      <input  type="password" name="uname">
+      <input  type="password" name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- two "pword" inputs, (text + password) -->
+    <form id="form3" action="formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="text"       name="pword">
+      <input  type="password"   name="qword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- same thing, different order -->
+    <form id="form4" action="formtest.js">
+      <input  type="text"       name="uname">
+      <input  type="password"   name="pword">
+      <input  type="text"       name="qword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- uname is not a type=text input (try a checkbox just for variety) -->
+    <form id="form5" action="formtest.js">
+      <input  type="checkbox" name="uname" value="">
+      <input  type="password" name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- pword is not a type=password input (try a checkbox just for variety) -->
+    <form id="form6" action="formtest.js">
+      <input  type="text"     name="uname">
+      <input  type="checkbox" name="pword" value="">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>
+
+    <!-- pword is not a type=password input -->
+    <form id="form7" action="formtest.js">
+      <input  type="text" name="uname" value="testuser">
+      <input  type="text" name="pword">
+
+      <button type="submit">Submit</button>
+      <button type="reset"> Reset </button>
+    </form>`, win, 4);
+
+  await checkLoginFormInFrameWithElementValues(win, 1, "", "");
+  await checkLoginFormInFrameWithElementValues(win, 2, "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, 3, "", "testuser", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, 4, "testuser", "testpass", "");
+  await checkLoginFormInFrameWithElementValues(win, 5, "", "testpass");
+  await checkLoginFormInFrameWithElementValues(win, 6, "", "");
+  await checkLoginFormInFrameWithElementValues(win, 7, "testuser", "");
+
+  SimpleTest.finish();
+}
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_primary_password.html b/toolkit/components/passwordmgr/test/mochitest/test_primary_password.html
new file mode 100644
index 0000000000..4da6929b61
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_primary_password.html
@@ -0,0 +1,296 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for primary password</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="text/javascript" src="../../../prompts/test/prompt_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: primary password.
+
+<p id="display"></p>
+
+<div id="content" style="display: none">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+"use strict";
+
+// Force parent to not look for tab-modal prompts, as they're not used for auth prompts.
+modalType = Ci.nsIPrompt.MODAL_TYPE_WINDOW;
+
+const exampleCom = "https://example.com/tests/toolkit/components/passwordmgr/test/mochitest/";
+const exampleOrg = "https://example.org/tests/toolkit/components/passwordmgr/test/mochitest/";
+
+const win = window.open("about:blank");
+SimpleTest.registerCleanupFunction(() => win.close());
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    ["http://mochi.test:8888", "http://mochi.test:8888", null, "testuser", "testpass", "uname", "pword"],
+    ["https://example.com", "https://example.com", null, "user1", "pass1", "uname", "pword"],
+    ["https://example.org", "https://example.org", null, "user2", "pass2", "uname", "pword"]
+  );
+  ok(await isLoggedIn(), "should be initially logged in (no PP)");
+  enablePrimaryPassword();
+  ok(!await isLoggedIn(), "should be logged out after setting PP");
+});
+
+add_task(async function test_1() {
+  // Trigger a MP prompt via the API
+  const state = {
+    msg: "Please enter your Primary Password.",
+    title: "the title",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: true,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "passField",
+    defButton: "button0",
+  };
+  const action = {
+    buttonClick: "ok",
+    passField: LoginTestUtils.primaryPassword.primaryPassword,
+  };
+  const promptDone = handlePrompt(state, action);
+
+  const logins = await LoginManager.getAllLogins();
+
+  await promptDone;
+  is(logins.length, 3, "expected number of logins");
+
+  ok(await isLoggedIn(), "should be logged in after MP prompt");
+  logoutPrimaryPassword();
+  ok(!await isLoggedIn(), "should be logged out");
+});
+
+add_task(async function test_2() {
+  // Try again but click cancel.
+  const state = {
+    msg: "Please enter your Primary Password.",
+    title: "the title",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: true,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "passField",
+    defButton: "button0",
+  };
+  const action = {
+    buttonClick: "cancel",
+  };
+  const promptDone = handlePrompt(state, action);
+
+  const logins = await LoginManager.getAllLogins().catch(() => {});
+  await promptDone;
+  is(logins, undefined, "shouldn't have gotten logins");
+  ok(!await isLoggedIn(), "should still be logged out");
+});
+
+add_task(async function test_3() {
+  const state = {
+    msg: "Please enter your Primary Password.",
+    title: "the title",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: true,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "passField",
+    defButton: "button0",
+  };
+  const action = {
+    buttonClick: "ok",
+    passField: LoginTestUtils.primaryPassword.primaryPassword,
+  };
+  const promptDone = handlePrompt(state, action);
+
+  const fillPromise = promiseFormsProcessed();
+
+  info("Load a single window to trigger a MP");
+  await SimpleTest.promiseFocus(win, true);
+  win.location = exampleCom + "subtst_primary_pass.html";
+
+  await promptDone;
+  info("promptDone");
+  await fillPromise;
+  info("filled");
+
+  // check contents of win fields
+
+  await SpecialPowers.spawn(win, [], function() {
+    const u = this.content.document.getElementById("userfield");
+    const p = this.content.document.getElementById("passfield");
+    Assert.equal(u.value, "user1", "checking expected user to have been filled in");
+    Assert.equal(p.value, "pass1", "checking expected pass to have been filled in");
+    u.value = "";
+    p.value = "";
+  });
+
+  ok(await isLoggedIn(), "should be logged in");
+  logoutPrimaryPassword();
+  ok(!await isLoggedIn(), "should be logged out");
+});
+
+add_task(async function test_4() {
+  const state = {
+    msg: "Please enter your Primary Password.",
+    title: "the title",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: true,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "passField",
+    defButton: "button0",
+  };
+  let action = {
+    buttonClick: "none",
+  };
+  const promptDone = handlePrompt(state, action);
+
+  // first part of loading 2 MP-triggering windows
+  await SimpleTest.promiseFocus(win);
+  win.location = exampleOrg + "subtst_primary_pass.html";
+  // The MP prompt is open but don't take any action yet.
+  await promptDone;
+
+  // check contents of win fields
+  await SpecialPowers.spawn(win, [], function() {
+    const u = this.content.document.getElementById("userfield");
+    const p = this.content.document.getElementById("passfield");
+    Assert.equal(u.value, "", "checking expected empty user");
+    Assert.equal(p.value, "", "checking expected empty pass");
+  });
+
+  ok(!await isLoggedIn(), "should be logged out");
+
+  // XXX check that there's 1 MP window open
+
+  // Load a second login form in an iframe
+  // This should detect that there's already a pending MP prompt, and not
+  // put up a second one.
+
+  // Since the Primary Password prompt is open, we can't focus another tab
+  // to load the second form. Instead, we load the same form into an iframe.
+  const url = exampleOrg + "subtst_primary_pass.html";
+  await SpecialPowers.spawn(win, [url], async function(urlF) {
+    const iframe = this.content.document.querySelector("iframe");
+    const loadPromise = new Promise(resolve => {
+      iframe.addEventListener("load", function onload() {
+        resolve();
+      }, { once: true });
+    });
+    // Use the same origin as the top level to ensure we would autofill
+    // if we could (we don't fill in cross-origin iframes).
+    iframe.src = urlF;
+    await loadPromise;
+  });
+
+  // We can't use promiseFormsProcessed* here, because _fillForm doesn't
+  // run if Primary Password is locked.
+  await new Promise(resolve => {
+    // Testing a negative, wait a little to give the login manager a chance to
+    // (incorrectly) fill in the form.  Note, we cannot use setTimeout()
+    // here because the modal window suspends all window timers.  Instead we
+    // must use a chrome script to use nsITimer directly.
+    const chromeURL = SimpleTest.getTestFileURL("chrome_timeout.js");
+    const script = SpecialPowers.loadChromeScript(chromeURL);
+    script.addMessageListener("ready", _ => {
+      script.sendAsyncMessage("setTimeout", { delay: 500 });
+    });
+    script.addMessageListener("timeout", resolve);
+  });
+
+  // iframe should load without having triggered a MP prompt (because one
+  // is already waiting)
+
+  // check contents of iframe fields
+  await SpecialPowers.spawn(win, [], function() {
+    const iframe = this.content.document.querySelector("iframe");
+    const frameDoc = iframe.contentDocument;
+    const u = frameDoc.getElementById("userfield");
+    const p = frameDoc.getElementById("passfield");
+    Assert.equal(u.value, "", "checking expected empty user");
+    Assert.equal(p.value, "", "checking expected empty pass");
+  });
+
+  // XXX check that there's 1 MP window open
+  ok(!await isLoggedIn(), "should be logged out");
+
+  // Ok, now enter the MP. The MP prompt is already up.
+  const fillPromise = promiseFormsProcessed(2);
+
+  // fill existing MP dialog with MP.
+  action = {
+    buttonClick: "ok",
+    passField: LoginTestUtils.primaryPassword.primaryPassword,
+  };
+  await handlePrompt(state, action);
+  await fillPromise;
+
+  // We shouldn't have to worry about win's load event racing with
+  // filling of the iframe's data. We notify observers synchronously, so
+  // the iframe's observer will process the iframe before win even finishes
+  // processing the form.
+  ok(await isLoggedIn(), "should be logged in");
+
+  // check contents of win fields
+  await SpecialPowers.spawn(win, [], function() {
+    const u = this.content.document.getElementById("userfield");
+    const p = this.content.document.getElementById("passfield");
+    Assert.equal(u.value, "user2", "checking expected user to have been filled in");
+    Assert.equal(p.value, "pass2", "checking expected pass to have been filled in");
+
+    // clearing fields to not cause a submission when the next document is loaded
+    u.value = "";
+    p.value = "";
+  });
+
+  // check contents of iframe fields
+  await SpecialPowers.spawn(win, [], function() {
+    const iframe = this.content.document.querySelector("iframe");
+    const frameDoc = iframe.contentDocument;
+    const u = frameDoc.getElementById("userfield");
+    const p = frameDoc.getElementById("passfield");
+    Assert.equal(u.value, "user2", "checking expected user to have been filled in");
+    Assert.equal(p.value, "pass2", "checking expected pass to have been filled in");
+
+    // clearing fields to not cause a submission when the next document is loaded
+    u.value = "";
+    p.value = "";
+  });
+});
+
+// XXX do a test5ABC with clicking cancel?
+
+SimpleTest.registerCleanupFunction(function finishTest() {
+  disablePrimaryPassword();
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_prompt.html b/toolkit/components/passwordmgr/test/mochitest/test_prompt.html
new file mode 100644
index 0000000000..12d3a7d080
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_prompt.html
@@ -0,0 +1,669 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test prompter.{prompt,asyncPromptPassword,asyncPromptUsernameAndPassword}</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="text/javascript" src="../../../prompts/test/prompt_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+var state, action;
+var uname  = { value: null };
+var pword  = { value: null };
+var result = { value: null };
+var isOk;
+
+// Force parent to not look for tab-modal prompts, as they're not used for auth prompts.
+modalType = Ci.nsIPrompt.MODAL_TYPE_WINDOW;
+
+let prompterParent = runInParent(() => {
+  const promptFac = Cc["@mozilla.org/passwordmanager/authpromptfactory;1"].
+                    getService(Ci.nsIPromptFactory);
+
+  let chromeWin = Services.wm.getMostRecentWindow("navigator:browser");
+  let prompter1 = promptFac.getPrompt(chromeWin, Ci.nsIAuthPrompt);
+
+  addMessageListener("proxyPrompter", async function onMessage(msg) {
+    let rv = await prompter1[msg.methodName](...msg.args);
+    return {
+      rv,
+      // Send the args back to content so out/inout args can be checked.
+      args: msg.args,
+    };
+  });
+});
+
+let prompter1 = new PrompterProxy(prompterParent);
+
+const defaultTitle = "the title";
+const defaultMsg = "the message";
+
+add_setup(async () => {
+    await setStoredLoginsAsync(
+    ["http://example.com", null, "http://example.com", "", "examplepass", "", ""],
+    ["http://example2.com", null, "http://example2.com", "user1name", "user1pass", "", ""],
+    ["http://example2.com", null, "http://example2.com", "user2name", "user2pass", "", ""],
+    ["http://example2.com", null, "http://example2.com", "user3.name@host", "user3pass", "", ""],
+    ["http://example2.com", null, "http://example2.com", "100@beef", "user3pass", "", ""],
+    ["http://example2.com", null, "http://example2.com", "100%beef", "user3pass", "", ""]
+  );
+});
+
+add_task(async function test_prompt_accept() {
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "abc",
+    passValue: "",
+    iconClass: "question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: true,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    textField: "xyz",
+  };
+  promptDone = handlePrompt(state, action);
+  isOk = prompter1.prompt(defaultTitle, defaultMsg, "http://example.com",
+                          Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, "abc", result);
+  await promptDone;
+
+  ok(isOk, "Checking dialog return value (accept)");
+  is(result.value, "xyz", "Checking prompt() returned value");
+});
+
+add_task(async function test_prompt_cancel() {
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "abc",
+    passValue: "",
+    iconClass: "question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: true,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "cancel",
+  };
+  promptDone = handlePrompt(state, action);
+  isOk = prompter1.prompt(defaultTitle, defaultMsg, "http://example.com",
+                          Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, "abc", result);
+  await promptDone;
+  ok(!isOk, "Checking dialog return value (cancel)");
+});
+
+add_task(async function test_promptPassword_defaultAccept() {
+  // Default password provided, existing logins are ignored.
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "",
+    passValue: "inputpw",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: true,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "passField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    passField: "secret",
+  };
+  pword.value = "inputpw";
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "http://example.com",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "secret", "Checking returned password");
+});
+
+add_task(async function test_promptPassword_defaultCancel() {
+  // Default password provided, existing logins are ignored.
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "",
+    passValue: "inputpw",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: true,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "passField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "cancel",
+  };
+  pword.value = "inputpw";
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "http://example.com",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  await promptDone;
+  ok(!isOk, "Checking dialog return value (cancel)");
+});
+
+add_task(async function test_promptPassword_emptyAccept() {
+  // No default password provided, realm does not match existing login.
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: true,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "passField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    passField: "secret",
+  };
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "http://nonexample.com",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "secret", "Checking returned password");
+});
+
+add_task(async function test_promptPassword_saved() {
+  // No default password provided, matching login is returned w/o prompting.
+  pword.value = null;
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "http://example.com",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "examplepass", "Checking returned password");
+});
+
+add_task(async function test_promptPassword_noMatchingPasswordForEmptyUN() {
+  // No default password provided, none of the logins from this host are
+  // password-only so the user is prompted.
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: true,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "passField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    passField: "secret",
+  };
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "http://example2.com",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "secret", "Checking returned password");
+});
+
+add_task(async function test_promptPassword_matchingPWForUN() {
+  // No default password provided, matching login is returned w/o prompting.
+  pword.value = null;
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "http://user1name@example2.com",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "user1pass", "Checking returned password");
+});
+
+add_task(async function test_promptPassword_matchingPWForUN2() {
+  // No default password provided, matching login is returned w/o prompting.
+  pword.value = null;
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "http://user2name@example2.com",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "user2pass", "Checking returned password");
+});
+
+add_task(async function test_promptPassword_matchingPWForUN3() {
+  // No default password provided, matching login is returned w/o prompting.
+  pword.value = null;
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "http://user3%2Ename%40host@example2.com",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "user3pass", "Checking returned password");
+});
+
+add_task(async function test_promptPassword_extraAt() {
+  // No default password provided, matching login is returned w/o prompting.
+  pword.value = null;
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "http://100@beef@example2.com",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "user3pass", "Checking returned password");
+});
+
+add_task(async function test_promptPassword_usernameEncoding() {
+  // No default password provided, matching login is returned w/o prompting.
+  pword.value = null;
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "http://100%25beef@example2.com",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "user3pass", "Checking returned password");
+
+  // XXX test saving a password with  Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY
+});
+
+add_task(async function test_promptPassword_realm() {
+  // We don't pre-fill or save for NS_GetAuthKey-generated realms, but we should still prompt
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: true,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "passField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    passField: "fill2pass",
+  };
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "example2.com:80 (somerealm)",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "fill2pass", "Checking returned password");
+});
+
+add_task(async function test_promptPassword_realm2() {
+  // We don't pre-fill or save for NS_GetAuthKey-generated realms, but we should still prompt
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: true,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "passField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    passField: "fill2pass",
+  };
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptPassword(defaultTitle, defaultMsg, "example2.com:80 (somerealm)",
+                                  Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(pword.value, "fill2pass", "Checking returned password");
+});
+
+add_task(async function test_promptUsernameAndPassword_accept() {
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "inuser",
+    passValue: "inpass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    textField: "outuser",
+    passField: "outpass",
+  };
+  uname.value = "inuser";
+  pword.value = "inpass";
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptUsernameAndPassword(defaultTitle, defaultMsg, "http://nonexample.com",
+                                             Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, uname, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(uname.value, "outuser", "Checking returned username");
+  is(pword.value, "outpass", "Checking returned password");
+});
+
+add_task(async function test_promptUsernameAndPassword_cancel() {
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "inuser",
+    passValue: "inpass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "cancel",
+  };
+  uname.value = "inuser";
+  pword.value = "inpass";
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptUsernameAndPassword(defaultTitle, defaultMsg, "http://nonexample.com",
+                                             Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, uname, pword);
+  await promptDone;
+  ok(!isOk, "Checking dialog return value (cancel)");
+});
+
+add_task(async function test_promptUsernameAndPassword_autofill() {
+  // test filling in existing password-only login
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "",
+    passValue: "examplepass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+  };
+  uname.value = null;
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptUsernameAndPassword(defaultTitle, defaultMsg, "http://example.com",
+                                             Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY, uname, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(uname.value, "", "Checking returned username");
+  is(pword.value, "examplepass", "Checking returned password");
+});
+
+add_task(async function test_promptUsernameAndPassword_multipleExisting() {
+  // test filling in existing login (undetermined from multiple selection)
+  // user2name/user2pass would also be valid to fill here.
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "user1name",
+    passValue: "user1pass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+  };
+  uname.value = null;
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptUsernameAndPassword(defaultTitle, defaultMsg, "http://example2.com",
+                                             Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY, uname, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  ok(uname.value == "user1name" || uname.value == "user2name", "Checking returned username");
+  ok(pword.value == "user1pass" || uname.value == "user2pass", "Checking returned password");
+});
+
+add_task(async function test_promptUsernameAndPassword_multipleExisting1() {
+  // test filling in existing login (user1 from multiple selection)
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "user1name",
+    passValue: "user1pass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+  };
+  uname.value = "user1name";
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptUsernameAndPassword(defaultTitle, defaultMsg, "http://example2.com",
+                                             Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY, uname, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(uname.value, "user1name", "Checking returned username");
+  is(pword.value, "user1pass", "Checking returned password");
+});
+
+add_task(async function test_promptUsernameAndPassword_multipleExisting2() {
+  // test filling in existing login (user2 from multiple selection)
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "user2name",
+    passValue: "user2pass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+  };
+  uname.value = "user2name";
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptUsernameAndPassword(defaultTitle, defaultMsg, "http://example2.com",
+                                             Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY, uname, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(uname.value, "user2name", "Checking returned username");
+  is(pword.value, "user2pass", "Checking returned password");
+});
+
+add_task(async function test_promptUsernameAndPassword_passwordChange() {
+  // test changing password
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "user2name",
+    passValue: "user2pass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    passField: "NEWuser2pass",
+  };
+  uname.value = "user2name";
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptUsernameAndPassword(defaultTitle, defaultMsg, "http://example2.com",
+                                             Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY, uname, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(uname.value, "user2name", "Checking returned username");
+  is(pword.value, "NEWuser2pass", "Checking returned password");
+});
+
+add_task(async function test_promptUsernameAndPassword_changePasswordBack() {
+  // test changing password (back to original value)
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "user2name",
+    passValue: "NEWuser2pass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    passField: "user2pass",
+  };
+  uname.value = "user2name";
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptUsernameAndPassword(defaultTitle, defaultMsg, "http://example2.com",
+                                             Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY, uname, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(uname.value, "user2name", "Checking returned username");
+  is(pword.value, "user2pass", "Checking returned password");
+});
+
+add_task(async function test_promptUsernameAndPassword_realm() {
+  // We don't pre-fill or save for NS_GetAuthKey-generated realms, but we should still prompt
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    textField: "fill2user",
+    passField: "fill2pass",
+  };
+  uname.value = null;
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptUsernameAndPassword(defaultTitle, defaultMsg, "example2.com:80 (somerealm)",
+                                             Ci.nsIAuthPrompt.SAVE_PASSWORD_NEVER, uname, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(uname.value, "fill2user", "Checking returned username");
+  is(pword.value, "fill2pass", "Checking returned password");
+});
+
+add_task(async function test_promptUsernameAndPassword_realm2() {
+  // We don't pre-fill or save for NS_GetAuthKey-generated realms, but we should still prompt
+  state = {
+    msg: "the message",
+    title: "the title",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    textField: "fill2user",
+    passField: "fill2pass",
+  };
+  uname.value = null;
+  pword.value = null;
+  promptDone = handlePrompt(state, action);
+  isOk = await prompter1.asyncPromptUsernameAndPassword(defaultTitle, defaultMsg, "example2.com:80 (somerealm)",
+                                             Ci.nsIAuthPrompt.SAVE_PASSWORD_PERMANENTLY, uname, pword);
+  await promptDone;
+  ok(isOk, "Checking dialog return value (accept)");
+  is(uname.value, "fill2user", "Checking returned username");
+  is(pword.value, "fill2pass", "Checking returned password");
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_prompt_async.html b/toolkit/components/passwordmgr/test/mochitest/test_prompt_async.html
new file mode 100644
index 0000000000..41a58cb416
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_prompt_async.html
@@ -0,0 +1,621 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+    <meta charset="utf-8">
+    <title>Test for Async Auth Prompt</title>
+    <script type="text/javascript" src="/MochiKit/MochiKit.js"></script>
+    <script src="/tests/SimpleTest/SimpleTest.js"></script>
+    <script type="text/javascript" src="pwmgr_common.js"></script>
+    <script type="text/javascript" src="../../../prompts/test/prompt_common.js"></script>
+    <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+
+    <script class="testbody" type="text/javascript">
+      const { NetUtil } = SpecialPowers.ChromeUtils.importESModule(
+        "resource://gre/modules/NetUtil.sys.mjs"
+      );
+      const { TestUtils } = SpecialPowers.ChromeUtils.importESModule(
+        "resource://testing-common/TestUtils.sys.mjs"
+      );
+      const EXAMPLE_COM = "http://example.com/tests/toolkit/components/passwordmgr/test/mochitest/";
+      const EXAMPLE_ORG = "http://example.org/tests/toolkit/components/passwordmgr/test/mochitest/";
+      let mozproxyOrigin;
+
+      // Let prompt_common know what kind of modal type is enabled for auth prompts.
+      modalType = authPromptModalType;
+
+      // These are magically defined on the window due to the iframe IDs
+      /* global iframe1, iframe2a, iframe2b */
+
+      /**
+       * Add a listener to add some logins to be autofilled in the HTTP/proxy auth. prompts later.
+       */
+      let pwmgrParent = runInParent(() => {
+        Services.prefs.setIntPref("network.auth.subresource-http-auth-allow", 2);
+        Services.prefs.setIntPref("prompts.authentication_dialog_abuse_limit", -1);
+
+        addMessageListener("initLogins", async function onMessage(msg) {
+          const loginsData = [
+            [msg.mozproxyOrigin, "proxy_realm", "proxy_user", "proxy_pass"],
+            [msg.mozproxyOrigin, "proxy_realm2", "proxy_user2", "proxy_pass2"],
+            [msg.mozproxyOrigin, "proxy_realm3", "proxy_user3", "proxy_pass3"],
+            [msg.mozproxyOrigin, "proxy_realm4", "proxy_user4", "proxy_pass4"],
+            [msg.mozproxyOrigin, "proxy_realm5", "proxy_user5", "proxy_pass5"],
+            ["http://example.com", "mochirealm", "user1name", "user1pass"],
+            ["http://example.org", "mochirealm2", "user2name", "user2pass"],
+            ["http://example.com", "mochirealm3", "user3name", "user3pass"],
+            ["http://example.com", "mochirealm4", "user4name", "user4pass"],
+            ["http://example.com", "mochirealm5", "user5name", "user5pass"],
+            ["http://example.com", "mochirealm6", "user6name", "user6pass"]
+          ];
+          const logins = loginsData.map(([host, realm, user, pass]) => {
+            const login = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(Ci.nsILoginInfo);
+            login.init(host, null, realm, user, pass, "", "");
+            return login
+          })
+          await Services.logins.addLogins(logins);
+        });
+      }); // end runInParent
+
+      function promiseLoadedContentDoc(frame) {
+        return new Promise(resolve => {
+          frame.addEventListener("load", function onLoad(evt) {
+            resolve(SpecialPowers.wrap(frame).contentDocument);
+          }, { once: true });
+        });
+      }
+
+      function promiseProxyErrorLoad(frame) {
+        return TestUtils.waitForCondition(async function checkForProxyConnectFailure() {
+          try {
+            return await SpecialPowers.spawn(frame, [], function() {
+              return this.content.document.documentURI.includes("proxyConnectFailure");
+            })
+          } catch (e) {
+            // The frame may not be ready for the 'spawn' task right after setting
+            // iframe.src, which will throw an exception when that happens.
+            // Since this test is testing error load, we can't wait until the iframe
+            // is 'loaded' either. So we simply catch the exception here and retry the task
+            // later since we are in the waitForCondition loop.
+            return false;
+          }
+        }, "Waiting for proxyConnectFailure documentURI");
+      }
+
+      /**
+       * Make a channel to get the ProxyInfo used by the test harness so that we
+       * can add logins for the correct proxy origin.
+       */
+      add_task(async function setup_getProxyInfoForHarness() {
+        await new Promise(resolve => {
+          let resolveCallback = SpecialPowers.wrapCallbackObject({
+            // eslint-disable-next-line mozilla/use-chromeutils-generateqi
+            QueryInterface(iid) {
+              const interfaces = [Ci.nsIProtocolProxyCallback, Ci.nsISupports];
+
+              if (!interfaces.some(v => iid.equals(v))) {
+                throw SpecialPowers.Cr.NS_ERROR_NO_INTERFACE;
+              }
+              return this;
+            },
+
+            onProxyAvailable(req, uri, pi, status) {
+              // Add logins using the proxy host and port used by the mochitest harness.
+              mozproxyOrigin = "moz-proxy://" + SpecialPowers.wrap(pi).host + ":" +
+                SpecialPowers.wrap(pi).port;
+
+              pwmgrParent.sendQuery("initLogins", {mozproxyOrigin}).then(resolve)
+            },
+          });
+
+          // Need to allow for arbitrary network servers defined in PAC instead of a hardcoded moz-proxy.
+          let channel = NetUtil.newChannel({
+            uri: "http://example.com",
+            loadUsingSystemPrincipal: true,
+          });
+
+          let pps = SpecialPowers.Cc["@mozilla.org/network/protocol-proxy-service;1"]
+                                 .getService();
+
+          pps.asyncResolve(channel, 0, resolveCallback);
+        });
+      });
+
+      add_task(async function test_proxyAuthThenTwoHTTPAuth() {
+        // Load through a single proxy with authentication required 3 different
+        // pages, first with one login, other two with their own different login.
+        // We expect to show just a single dialog for proxy authentication and
+        // then two dialogs to authenticate to login 1 and then login 2.
+
+        let iframe1DocPromise = promiseLoadedContentDoc(iframe1);
+        let iframe2aDocPromise = promiseLoadedContentDoc(iframe2a);
+        let iframe2bDocPromise = promiseLoadedContentDoc(iframe2b);
+
+        iframe1.src = EXAMPLE_COM + "authenticate.sjs?" +
+          "r=1&" +
+          "user=user1name&" +
+          "pass=user1pass&" +
+          "realm=mochirealm&" +
+          "proxy_user=proxy_user&" +
+          "proxy_pass=proxy_pass&" +
+          "proxy_realm=proxy_realm";
+        iframe2a.src = EXAMPLE_ORG + "authenticate.sjs?" +
+          "r=2&" +
+          "user=user2name&" +
+          "pass=user2pass&" +
+          "realm=mochirealm2&" +
+          "proxy_user=proxy_user&" +
+          "proxy_pass=proxy_pass&" +
+          "proxy_realm=proxy_realm";
+        iframe2b.src = EXAMPLE_ORG + "authenticate.sjs?" +
+          "r=3&" +
+          "user=user2name&" +
+          "pass=user2pass&" +
+          "realm=mochirealm2&" +
+          "proxy_user=proxy_user&" +
+          "proxy_pass=proxy_pass&" +
+          "proxy_realm=proxy_realm";
+
+        let state = {
+          msg: `The proxy ${mozproxyOrigin} is requesting a username and password. The site says: “proxy_realm”`,
+          title: "Authentication Required",
+          textValue: "proxy_user",
+          passValue: "proxy_pass",
+          iconClass: "authentication-icon question-icon",
+          titleHidden: true,
+          textHidden: false,
+          passHidden: false,
+          checkHidden: true,
+          checkMsg: "",
+          checked: false,
+          focused: "textField",
+          defButton: "button0",
+        };
+        let action = {
+          buttonClick: "ok",
+        };
+        await handlePrompt(state, action);
+
+        // We don't know what order these prompts appear in so get both states and check them.
+        // We can't use Promise.all here since we can't start the 2nd timer in chromeScript.js until
+        // the first timer is done since the timer variable gets clobbered, plus we don't want
+        // different actions racing each other.
+        let promptStates = [
+          await handlePromptWithoutChecks(action),
+          await handlePromptWithoutChecks(action),
+        ];
+
+        let expected1 = Object.assign({}, state, {
+          msg: "This site is asking you to sign in. Warning: Your login information will be shared with example.com, not the website you are currently visiting.",
+          textValue: "user1name",
+          passValue: "user1pass",
+        });
+
+        let expected2 = Object.assign({}, state, {
+          msg: "This site is asking you to sign in. Warning: Your login information will be shared with example.org, not the website you are currently visiting.",
+          textValue: "user2name",
+          passValue: "user2pass",
+        });
+
+        // The order isn't important.
+        let expectedPromptStates = [
+          expected1,
+          expected2,
+        ];
+
+        is(promptStates.length, expectedPromptStates.length,
+           "Check we handled the right number of prompts");
+        for (let promptState of promptStates) {
+          let expectedStateIndexForMessage = expectedPromptStates.findIndex(eps => {
+            return eps.msg == promptState.msg;
+          });
+          isnot(expectedStateIndexForMessage, -1, "Check state message was found in expected array");
+          let expectedPromptState = expectedPromptStates.splice(expectedStateIndexForMessage, 1)[0];
+          checkPromptState(promptState, expectedPromptState);
+        }
+
+        await iframe1DocPromise;
+        await iframe2aDocPromise;
+        await iframe2bDocPromise;
+
+        await SpecialPowers.spawn(getIframeBrowsingContext(window, 0), [], function() {
+          let doc = this.content.document;
+          let authok1 = doc.getElementById("ok").textContent;
+          let proxyok1 = doc.getElementById("proxy").textContent;
+          Assert.equal(authok1, "PASS", "WWW Authorization OK, frame1");
+          Assert.equal(proxyok1, "PASS", "Proxy Authorization OK, frame1");
+        });
+
+        await SpecialPowers.spawn(getIframeBrowsingContext(window, 1), [], function() {
+          let doc = this.content.document;
+          let authok2a = doc.getElementById("ok").textContent;
+          let proxyok2a = doc.getElementById("proxy").textContent;
+          Assert.equal(authok2a, "PASS", "WWW Authorization OK, frame2a");
+          Assert.equal(proxyok2a, "PASS", "Proxy Authorization OK, frame2a");
+        });
+
+        await SpecialPowers.spawn(getIframeBrowsingContext(window, 2), [], function() {
+          let doc = this.content.document;
+          let authok2b = doc.getElementById("ok").textContent;
+          let proxyok2b = doc.getElementById("proxy").textContent;
+          Assert.equal(authok2b, "PASS", "WWW Authorization OK, frame2b");
+          Assert.equal(proxyok2b, "PASS", "Proxy Authorization OK, frame2b");
+        });
+      });
+
+      add_task(async function test_threeSubframesWithSameProxyAndHTTPAuth() {
+        // Load an iframe with 3 subpages all requiring the same login through
+        // an authenticated proxy. We expect 2 dialogs, proxy authentication
+        // and web authentication.
+
+        let iframe1DocPromise = promiseLoadedContentDoc(iframe1);
+
+        iframe1.src = EXAMPLE_COM + "subtst_prompt_async.html";
+        iframe2a.src = "about:blank";
+        iframe2b.src = "about:blank";
+
+        let state = {
+          msg: `The proxy ${mozproxyOrigin} is requesting a username and password. The site says: “proxy_realm2”`,
+          title: "Authentication Required",
+          textValue: "proxy_user2",
+          passValue: "proxy_pass2",
+          iconClass: "authentication-icon question-icon",
+          titleHidden: true,
+          textHidden: false,
+          passHidden: false,
+          checkHidden: true,
+          checkMsg: "",
+          checked: false,
+          focused: "textField",
+          defButton: "button0",
+        };
+        let action = {
+          buttonClick: "ok",
+        };
+        await handlePrompt(state, action);
+
+        Object.assign(state, {
+          msg: "This site is asking you to sign in. Warning: Your login information will be shared with example.com, not the website you are currently visiting.",
+          textValue: "user3name",
+          passValue: "user3pass",
+        });
+        await handlePrompt(state, action);
+
+        await iframe1DocPromise;
+
+        function checkIframe(frameid) {
+          let doc = this.content.document;
+          let authok = doc.getElementById("ok").textContent;
+          let proxyok = doc.getElementById("proxy").textContent;
+
+          Assert.equal(authok, "PASS", "WWW Authorization OK, " + frameid);
+          Assert.equal(proxyok, "PASS", "Proxy Authorization OK, " + frameid);
+        }
+
+        let parentIFrameBC = SpecialPowers.wrap(window).windowGlobalChild
+                                          .browsingContext.children[0];
+
+        let childIFrame = SpecialPowers.unwrap(parentIFrameBC.children[0]);
+        await SpecialPowers.spawn(childIFrame, ["iframe1"], checkIframe);
+        childIFrame = SpecialPowers.unwrap(parentIFrameBC.children[1]);
+        await SpecialPowers.spawn(childIFrame, ["iframe2"], checkIframe);
+        childIFrame = SpecialPowers.unwrap(parentIFrameBC.children[2]);
+        await SpecialPowers.spawn(childIFrame, ["iframe3"], checkIframe);
+      });
+
+      add_task(async function test_oneFrameWithUnauthenticatedProxy() {
+        // Load in the iframe page through unauthenticated proxy
+        // and discard the proxy authentication. We expect to see
+        // unauthenticated page content and just a single dialog.
+
+        iframe1.src = EXAMPLE_COM + "authenticate.sjs?" +
+          "user=user4name&" +
+          "pass=user4pass&" +
+          "realm=mochirealm4&" +
+          "proxy_user=proxy_user3&" +
+          "proxy_pass=proxy_pass3&" +
+          "proxy_realm=proxy_realm3";
+
+        let state = {
+          msg: `The proxy ${mozproxyOrigin} is requesting a username and password. The site says: “proxy_realm3”`,
+          title: "Authentication Required",
+          textValue: "proxy_user3",
+          passValue: "proxy_pass3",
+          iconClass: "authentication-icon question-icon",
+          titleHidden: true,
+          textHidden: false,
+          passHidden: false,
+          checkHidden: true,
+          checkMsg: "",
+          checked: false,
+          focused: "textField",
+          defButton: "button0",
+        };
+        let action = {
+          buttonClick: "cancel",
+        };
+        await handlePrompt(state, action);
+
+        await promiseProxyErrorLoad(iframe1);
+      });
+
+      add_task(async function test_reloadReusingProxyAuthButCancellingHTTPAuth() {
+        // Reload the frame from previous step and pass the proxy authentication
+        // but cancel the WWW authentication. We should get the proxy=ok and WWW=fail
+        // content as a result.
+        let iframe1DocPromise = promiseLoadedContentDoc(iframe1);
+
+        iframe1.src = EXAMPLE_COM + "authenticate.sjs?" +
+          "user=user4name&" +
+          "pass=user4pass&" +
+          "realm=mochirealm4&" +
+          "proxy_user=proxy_user3&" +
+          "proxy_pass=proxy_pass3&" +
+          "proxy_realm=proxy_realm3";
+
+        let state = {
+          msg: `The proxy ${mozproxyOrigin} is requesting a username and password. The site says: “proxy_realm3”`,
+          title: "Authentication Required",
+          textValue: "proxy_user3",
+          passValue: "proxy_pass3",
+          iconClass: "authentication-icon question-icon",
+          titleHidden: true,
+          textHidden: false,
+          passHidden: false,
+          checkHidden: true,
+          checkMsg: "",
+          checked: false,
+          focused: "textField",
+          defButton: "button0",
+        };
+        let action = {
+          buttonClick: "ok",
+        };
+        await handlePrompt(state, action);
+
+        Object.assign(state, {
+          msg: "This site is asking you to sign in. Warning: Your login information will be shared with example.com, not the website you are currently visiting.",
+          textValue: "user4name",
+          passValue: "user4pass",
+        });
+        action = {
+          buttonClick: "cancel",
+        };
+        await handlePrompt(state, action);
+
+        await iframe1DocPromise;
+
+        await SpecialPowers.spawn(getIframeBrowsingContext(window, 0), [], function() {
+          let doc = this.content.document;
+          let authok1 = doc.getElementById("ok").textContent;
+          let proxyok1 = doc.getElementById("proxy").textContent;
+
+          Assert.equal(authok1, "FAIL", "WWW Authorization FAILED, frame1");
+          Assert.equal(proxyok1, "PASS", "Proxy Authorization OK, frame1");
+        });
+      });
+
+      add_task(async function test_hugePayloadCancelled() {
+        // Same as the previous two steps but let the server generate
+        // huge content load to check http channel is capable to handle
+        // case when auth dialog is canceled or accepted before unauthenticated
+        // content data is load from the server. (This would be better to
+        // implement using delay of server response).
+        iframe1.src = EXAMPLE_COM + "authenticate.sjs?" +
+          "user=user5name&" +
+          "pass=user5pass&" +
+          "realm=mochirealm5&" +
+          "proxy_user=proxy_user4&" +
+          "proxy_pass=proxy_pass4&" +
+          "proxy_realm=proxy_realm4&" +
+          "huge=1";
+
+        let state = {
+          msg: `The proxy ${mozproxyOrigin} is requesting a username and password. The site says: “proxy_realm4”`,
+          title: "Authentication Required",
+          textValue: "proxy_user4",
+          passValue: "proxy_pass4",
+          iconClass: "authentication-icon question-icon",
+          titleHidden: true,
+          textHidden: false,
+          passHidden: false,
+          checkHidden: true,
+          checkMsg: "",
+          checked: false,
+          focused: "textField",
+          defButton: "button0",
+        };
+        let action = {
+          buttonClick: "cancel",
+        };
+        await handlePrompt(state, action);
+
+        await promiseProxyErrorLoad(iframe1);
+      });
+
+      add_task(async function test_hugeProxySuccessWWWFail() {
+        // Reload the frame from the previous step and let the proxy
+        // authentication pass but WWW fail. We expect two dialogs
+        // and an unauthenticated page content load.
+
+        let iframe1DocPromise = promiseLoadedContentDoc(iframe1);
+        iframe1.src = EXAMPLE_COM + "authenticate.sjs?" +
+          "user=user5name&" +
+          "pass=user5pass&" +
+          "realm=mochirealm5&" +
+          "proxy_user=proxy_user4&" +
+          "proxy_pass=proxy_pass4&" +
+          "proxy_realm=proxy_realm4&" +
+          "huge=1";
+
+        let state = {
+          msg: `The proxy ${mozproxyOrigin} is requesting a username and password. The site says: “proxy_realm4”`,
+          title: "Authentication Required",
+          textValue: "proxy_user4",
+          passValue: "proxy_pass4",
+          iconClass: "authentication-icon question-icon",
+          titleHidden: true,
+          textHidden: false,
+          passHidden: false,
+          checkHidden: true,
+          checkMsg: "",
+          checked: false,
+          focused: "textField",
+          defButton: "button0",
+        };
+        let action = {
+          buttonClick: "ok",
+        };
+        await handlePrompt(state, action);
+
+        Object.assign(state, {
+          msg: "This site is asking you to sign in. Warning: Your login information will be shared with example.com, not the website you are currently visiting.",
+          textValue: "user5name",
+          passValue: "user5pass",
+        });
+        action = {
+          buttonClick: "cancel",
+        };
+        await handlePrompt(state, action);
+
+        await iframe1DocPromise;
+
+        await SpecialPowers.spawn(getIframeBrowsingContext(window, 0), [], function() {
+          let doc = this.content.document;
+          let authok1 = doc.getElementById("ok").textContent;
+          let proxyok1 = doc.getElementById("proxy").textContent;
+          let footnote = doc.getElementById("footnote").textContent;
+
+          Assert.equal(authok1, "FAIL", "WWW Authorization FAILED, frame1");
+          Assert.equal(proxyok1, "PASS", "Proxy Authorization OK, frame1");
+          Assert.equal(footnote, "This is a footnote after the huge content fill",
+             "Footnote present and loaded completely");
+        });
+      });
+
+      add_task(async function test_hugeProxySuccessWWWSuccess() {
+        // Reload again and let pass all authentication dialogs.
+        // Check we get the authenticated content not broken by
+        // the unauthenticated content.
+
+        let iframe1DocPromise = promiseLoadedContentDoc(iframe1);
+        await SpecialPowers.spawn(iframe1, [], function() {
+          this.content.document.location.reload();
+        });
+
+        let state = {
+          msg: "This site is asking you to sign in. Warning: Your login information will be shared with example.com, not the website you are currently visiting.",
+          title: "Authentication Required",
+          textValue: "user5name",
+          passValue: "user5pass",
+          iconClass: "authentication-icon question-icon",
+          titleHidden: true,
+          textHidden: false,
+          passHidden: false,
+          checkHidden: true,
+          checkMsg: "",
+          checked: false,
+          focused: "textField",
+          defButton: "button0",
+        };
+        let action = {
+          buttonClick: "ok",
+        };
+        await handlePrompt(state, action);
+
+        await iframe1DocPromise;
+
+        await SpecialPowers.spawn(getIframeBrowsingContext(window, 0), [], function() {
+          let doc = this.content.document;
+          let authok1 = doc.getElementById("ok").textContent;
+          let proxyok1 = doc.getElementById("proxy").textContent;
+          let footnote = doc.getElementById("footnote").textContent;
+
+          Assert.equal(authok1, "PASS", "WWW Authorization OK, frame1");
+          Assert.equal(proxyok1, "PASS", "Proxy Authorization OK, frame1");
+          Assert.equal(footnote, "This is a footnote after the huge content fill",
+             "Footnote present and loaded completely");
+        });
+      });
+
+      add_task(async function test_cancelSome() {
+        // Check we process all challenges sent by server when
+        // user cancels prompts
+        let iframe1DocPromise = promiseLoadedContentDoc(iframe1);
+        iframe1.src = EXAMPLE_COM + "authenticate.sjs?" +
+          "user=user6name&" +
+          "pass=user6pass&" +
+          "realm=mochirealm6&" +
+          "proxy_user=proxy_user5&" +
+          "proxy_pass=proxy_pass5&" +
+          "proxy_realm=proxy_realm5&" +
+          "huge=1&" +
+          "multiple=3";
+
+        let state = {
+          msg: `The proxy ${mozproxyOrigin} is requesting a username and password. The site says: “proxy_realm5”`,
+          title: "Authentication Required",
+          textValue: "proxy_user5",
+          passValue: "proxy_pass5",
+          iconClass: "authentication-icon question-icon",
+          titleHidden: true,
+          textHidden: false,
+          passHidden: false,
+          checkHidden: true,
+          checkMsg: "",
+          checked: false,
+          focused: "textField",
+          defButton: "button0",
+        };
+        let action = {
+          buttonClick: "cancel",
+        };
+        await handlePrompt(state, action);
+
+        action = {
+          buttonClick: "cancel",
+        };
+        await handlePrompt(state, action);
+
+        action = {
+          buttonClick: "ok",
+        };
+        await handlePrompt(state, action);
+
+        Object.assign(state, {
+          msg: "This site is asking you to sign in. Warning: Your login information will be shared with example.com, not the website you are currently visiting.",
+          textValue: "user6name",
+          passValue: "user6pass",
+        });
+
+        action = {
+          buttonClick: "cancel",
+        };
+        await handlePrompt(state, action);
+
+        action = {
+          buttonClick: "ok",
+        };
+        await handlePrompt(state, action);
+
+        await iframe1DocPromise;
+        await SpecialPowers.spawn(getIframeBrowsingContext(window, 0), [], function() {
+          let doc = this.content.document;
+          let authok1 = doc.getElementById("ok").textContent;
+          let proxyok1 = doc.getElementById("proxy").textContent;
+          let footnote = doc.getElementById("footnote").textContent;
+
+          Assert.equal(authok1, "PASS", "WWW Authorization OK, frame1");
+          Assert.equal(proxyok1, "PASS", "Proxy Authorization OK, frame1");
+          Assert.equal(footnote, "This is a footnote after the huge content fill",
+             "Footnote present and loaded completely");
+        });
+
+      });
+    </script>
+</head>
+<body>
+    <iframe id="iframe1"></iframe>
+    <iframe id="iframe2a"></iframe>
+    <iframe id="iframe2b"></iframe>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_prompt_http.html b/toolkit/components/passwordmgr/test/mochitest/test_prompt_http.html
new file mode 100644
index 0000000000..f6f6e681dc
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_prompt_http.html
@@ -0,0 +1,319 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test HTTP auth prompts by loading authenticate.sjs</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="text/javascript" src="../../../prompts/test/prompt_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+  <iframe id="iframe"></iframe>
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+var iframe = document.getElementById("iframe");
+
+// Let prompt_common know what kind of modal type is enabled for auth prompts.
+modalType = authPromptModalType;
+
+const AUTHENTICATE_PATH = new URL("authenticate.sjs", window.location.href).pathname;
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    ["http://mochi.test:8888", null, "mochitest", "mochiuser1", "mochipass1", "", ""],
+    ["http://mochi.test:8888", null, "mochitest2", "mochiuser2", "mochipass2", "", ""],
+    ["http://mochi.test:8888", null, "mochitest3", "mochiuser3", "mochipass3-old", "", ""],
+    // Logins to test scheme upgrades (allowed) and downgrades (disallowed)
+    ["http://example.com", null, "schemeUpgrade", "httpUser", "httpPass", "", ""],
+    ["https://example.com", null, "schemeDowngrade", "httpsUser", "httpsPass", "", ""],
+    // HTTP and HTTPS version of the same domain and realm but with different passwords.
+    ["http://example.org", null, "schemeUpgradeDedupe", "dedupeUser", "httpPass", "", ""],
+    ["https://example.org", null, "schemeUpgradeDedupe", "dedupeUser", "httpsPass", "", ""]
+  );
+});
+
+add_task(async function test_iframe() {
+  let state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "mochiuser1",
+    passValue: "mochipass1",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  let action = {
+    buttonClick: "ok",
+  };
+  promptDone = handlePrompt(state, action);
+
+  // The following tests are driven by iframe loads
+
+  var iframeLoaded = onloadPromiseFor("iframe");
+  iframe.src = "authenticate.sjs?user=mochiuser1&pass=mochipass1";
+  await promptDone;
+  await iframeLoaded;
+  await checkEchoedAuthInfo({user: "mochiuser1", pass: "mochipass1"},
+                            iframe);
+
+  state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "mochiuser2",
+    passValue: "mochipass2",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+  };
+  promptDone = handlePrompt(state, action);
+  // We've already authenticated to this host:port. For this next
+  // request, the existing auth should be sent, we'll get a 401 reply,
+  // and we should prompt for new auth.
+  iframeLoaded = onloadPromiseFor("iframe");
+  iframe.src = "authenticate.sjs?user=mochiuser2&pass=mochipass2&realm=mochitest2";
+  await promptDone;
+  await iframeLoaded;
+  await checkEchoedAuthInfo({user: "mochiuser2", pass: "mochipass2"},
+                            iframe);
+
+  // Now make a load that requests the realm from test 1000. It was
+  // already provided there, so auth will *not* be prompted for -- the
+  // networking layer already knows it!
+  iframeLoaded = onloadPromiseFor("iframe");
+  iframe.src = "authenticate.sjs?user=mochiuser1&pass=mochipass1";
+  await iframeLoaded;
+  await checkEchoedAuthInfo({user: "mochiuser1", pass: "mochipass1"},
+                            iframe);
+
+  // Same realm we've already authenticated to, but with a different
+  // expected password (to trigger an auth prompt, and change-password
+  // popup notification).
+  state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "mochiuser1",
+    passValue: "mochipass1",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    passField: "mochipass1-new",
+  };
+  promptDone = handlePrompt(state, action);
+  iframeLoaded = onloadPromiseFor("iframe");
+  let promptShownPromise = promisePromptShown("passwordmgr-prompt-change");
+  iframe.src = "authenticate.sjs?user=mochiuser1&pass=mochipass1-new";
+  await promptDone;
+  await iframeLoaded;
+  await checkEchoedAuthInfo({user: "mochiuser1", pass: "mochipass1-new"},
+                            iframe);
+  await promptShownPromise;
+
+  // Same as last test, but for a realm we haven't already authenticated
+  // to (but have an existing saved login for, so that we'll trigger
+  // a change-password popup notification.
+  state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "mochiuser3",
+    passValue: "mochipass3-old",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    passField: "mochipass3-new",
+  };
+  promptDone = handlePrompt(state, action);
+  iframeLoaded = onloadPromiseFor("iframe");
+  promptShownPromise = promisePromptShown("passwordmgr-prompt-change");
+  iframe.src = "authenticate.sjs?user=mochiuser3&pass=mochipass3-new&realm=mochitest3";
+  await promptDone;
+  await iframeLoaded;
+  await checkEchoedAuthInfo({user: "mochiuser3", pass: "mochipass3-new"},
+                            iframe);
+  await promptShownPromise;
+
+  // Housekeeping: Delete login4 to test the save prompt in the next test.
+  runInParent(() => {
+    var tmpLogin = Cc["@mozilla.org/login-manager/loginInfo;1"].
+                   createInstance(Ci.nsILoginInfo);
+    tmpLogin.init("http://mochi.test:8888", null, "mochitest3",
+                  "mochiuser3", "mochipass3-old", "", "");
+    Services.logins.removeLogin(tmpLogin);
+
+    // Clear cached auth from this subtest, and avoid leaking due to bug 459620.
+    var authMgr = Cc["@mozilla.org/network/http-auth-manager;1"].
+                  getService(Ci.nsIHttpAuthManager);
+    authMgr.clearAll();
+  });
+
+  state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "",
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  action = {
+    buttonClick: "ok",
+    textField: "mochiuser3",
+    passField: "mochipass3-old",
+  };
+  // Trigger a new prompt, so we can test adding a new login.
+  promptDone = handlePrompt(state, action);
+
+  iframeLoaded = onloadPromiseFor("iframe");
+  promptShownPromise = promisePromptShown("passwordmgr-prompt-save");
+  iframe.src = "authenticate.sjs?user=mochiuser3&pass=mochipass3-old&realm=mochitest3";
+  await promptDone;
+  await iframeLoaded;
+  await checkEchoedAuthInfo({user: "mochiuser3", pass: "mochipass3-old"},
+                            iframe);
+  await promptShownPromise;
+});
+
+add_task(async function test_schemeUpgrade() {
+  let state = {
+    msg: "This site is asking you to sign in. Warning: Your login information " +
+      "will be shared with example.com, not the website you are currently visiting.",
+    title: "Authentication Required",
+    textValue: "httpUser",
+    passValue: "httpPass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  let action = {
+    buttonClick: "ok",
+  };
+  let promptDone = handlePrompt(state, action);
+
+  // The following tests are driven by iframe loads
+
+  let iframeLoaded = onloadPromiseFor("iframe");
+  iframe.src = "https://example.com" + AUTHENTICATE_PATH +
+               "?user=httpUser&pass=httpPass&realm=schemeUpgrade";
+  await promptDone;
+  await iframeLoaded;
+  await checkEchoedAuthInfo({user: "httpUser", pass: "httpPass"},
+                            iframe);
+});
+
+add_task(async function test_schemeDowngrade() {
+  const state = {
+    msg: "This site is asking you to sign in. Warning: Your login information " +
+      "will be shared with example.com, not the website you are currently visiting.",
+    title: "Authentication Required",
+    textValue: "", // empty because we shouldn't downgrade
+    passValue: "",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  const action = {
+    buttonClick: "cancel",
+  };
+  const promptDone = handlePrompt(state, action);
+
+  // The following tests are driven by iframe loads
+
+  const iframeLoaded = onloadPromiseFor("iframe");
+  iframe.src = "http://example.com" + AUTHENTICATE_PATH +
+               "?user=unused&pass=unused&realm=schemeDowngrade";
+  await promptDone;
+  await iframeLoaded;
+});
+
+add_task(async function test_schemeUpgrade_dedupe() {
+  const state = {
+    msg: "This site is asking you to sign in. Warning: Your login information " +
+      "will be shared with example.org, not the website you are currently visiting.",
+    title: "Authentication Required",
+    textValue: "dedupeUser",
+    passValue: "httpsPass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  const action = {
+    buttonClick: "ok",
+  };
+  const promptDone = handlePrompt(state, action);
+
+  // The following tests are driven by iframe loads
+
+  const iframeLoaded = onloadPromiseFor("iframe");
+  iframe.src = "https://example.org" + AUTHENTICATE_PATH +
+               "?user=dedupeUser&pass=httpsPass&realm=schemeUpgradeDedupe";
+  await promptDone;
+  await iframeLoaded;
+  await checkEchoedAuthInfo({user: "dedupeUser", pass: "httpsPass"},
+                            iframe);
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_prompt_noWindow.html b/toolkit/components/passwordmgr/test/mochitest/test_prompt_noWindow.html
new file mode 100644
index 0000000000..19d05e47e5
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_prompt_noWindow.html
@@ -0,0 +1,72 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test HTTP auth prompts by loading authenticate.sjs with no window</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="text/javascript" src="../../../prompts/test/prompt_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+// Let prompt_common know what kind of modal type is enabled for auth prompts.
+modalType = authPromptModalType;
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    ["http://mochi.test:8888", null, "mochitest", "mochiuser1", "mochipass1", "", ""]
+  );
+});
+
+add_task(async function test_sandbox_xhr() {
+  const state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "mochiuser1",
+    passValue: "mochipass1",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  const action = {
+    buttonClick: "ok",
+  };
+  const promptDone = handlePrompt(state, action);
+
+  const url = new URL("authenticate.sjs?user=mochiuser1&pass=mochipass1", window.location.href);
+  const sandboxConstructor = SpecialPowers.Cu.Sandbox;
+  const sandbox = new sandboxConstructor(this, {wantXrays: true});
+  function sandboxedRequest(sandboxedUrl) {
+    const req = new XMLHttpRequest();
+    req.open("GET", sandboxedUrl, true);
+    req.send(null);
+  }
+
+  const loginModifiedPromise = promiseStorageChanged(["modifyLogin"]);
+  sandbox.sandboxedRequest = sandboxedRequest(url);
+  info("send the XHR request in the sandbox");
+  SpecialPowers.Cu.evalInSandbox("sandboxedRequest;", sandbox);
+
+  await promptDone;
+  info("prompt shown, waiting for metadata updates");
+  // Ensure the timeLastUsed and timesUsed metadata are updated.
+  await loginModifiedPromise;
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_prompt_promptAuth.html b/toolkit/components/passwordmgr/test/mochitest/test_prompt_promptAuth.html
new file mode 100644
index 0000000000..b82ea67faa
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_prompt_promptAuth.html
@@ -0,0 +1,370 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test promptAuth prompts</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="text/javascript" src="../../../prompts/test/prompt_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+const level = Ci.nsIAuthPrompt2.LEVEL_NONE;
+const authinfo = {
+  username: "",
+  password: "",
+  domain: "",
+
+  flags: Ci.nsIAuthInformation.AUTH_HOST,
+  authenticationScheme: "basic",
+  realm: "",
+};
+
+// Let prompt_common know what kind of modal type is enabled for auth prompts.
+modalType = authPromptModalType;
+
+const prompterParent = runInParent(() => {
+  const promptFac = Cc["@mozilla.org/passwordmanager/authpromptfactory;1"].
+                    getService(Ci.nsIPromptFactory);
+
+  const chromeWin = Services.wm.getMostRecentWindow("navigator:browser");
+  const prompter2 = promptFac.getPrompt(chromeWin, Ci.nsIAuthPrompt2);
+  prompter2.QueryInterface(Ci.nsILoginManagerAuthPrompter).browser = chromeWin.gBrowser.selectedBrowser;
+
+  const channels = {};
+  channels.channel1 = Services.io.newChannel("http://example.com",
+                                             null,
+                                             null,
+                                             null, // aLoadingNode
+                                             Services.
+                                             scriptSecurityManager.getSystemPrincipal(),
+                                             null, // aTriggeringPrincipal
+                                             Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL,
+                                             Ci.nsIContentPolicy.TYPE_OTHER);
+
+  channels.channel2 = Services.io.newChannel("http://example2.com",
+                                             null,
+                                             null,
+                                             null, // aLoadingNode
+                                             Services.
+                                             scriptSecurityManager.getSystemPrincipal(),
+                                             null, // aTriggeringPrincipal
+                                             Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL,
+                                             Ci.nsIContentPolicy.TYPE_OTHER);
+
+  addMessageListener("proxyPrompter", function onMessage(msg) {
+    const args = [...msg.args];
+    const channelName = args.shift();
+    // Replace the channel name string (arg. 0) with the channel by that name.
+    args.unshift(channels[channelName]);
+
+    const rv = prompter2[msg.methodName](...args);
+    return {
+      rv,
+      // Send the args back to content so out/inout args can be checked.
+      args: msg.args,
+    };
+  });
+});
+
+const prompter2 = new PrompterProxy(prompterParent);
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    ["http://example.com", null, "http://example.com", "", "examplepass", "", ""],
+    ["http://example2.com", null, "http://example2.com", "user1name", "user1pass", "", ""],
+    ["http://example2.com", null, "http://example2.com", "user2name", "user2pass", "", ""],
+    ["http://example2.com", null, "http://example2.com", "user3.name@host", "user3pass", "", ""],
+    ["http://example2.com", null, "http://example2.com", "100@beef", "user3pass", "", ""],
+    ["http://example2.com", null, "http://example2.com", "100%beef", "user3pass", "", ""]
+  );
+});
+
+add_task(async function test_accept() {
+  const state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "inuser",
+    passValue: "inpass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  const action = {
+    buttonClick: "ok",
+    textField: "outuser",
+    passField: "outpass",
+  };
+  authinfo.username = "inuser";
+  authinfo.password = "inpass";
+  authinfo.realm    = "some realm";
+
+  promptDone = handlePrompt(state, action);
+  // Since prompter2 is actually a proxy to send a message to a chrome script and
+  // we can't send a channel in a message, we instead send the channel name that
+  // already exists in the chromeScript.
+  const isOk = prompter2.promptAuth("channel1", level, authinfo);
+  await promptDone;
+
+  ok(isOk, "Checking dialog return value (accept)");
+  is(authinfo.username, "outuser", "Checking returned username");
+  is(authinfo.password, "outpass", "Checking returned password");
+});
+
+add_task(async function test_cancel() {
+  const state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "outuser",
+    passValue: "outpass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  const action = {
+    buttonClick: "cancel",
+  };
+  promptDone = handlePrompt(state, action);
+  const isOk = prompter2.promptAuth("channel1", level, authinfo);
+  await promptDone;
+
+  ok(!isOk, "Checking dialog return value (cancel)");
+});
+
+add_task(async function test_pwonly() {
+  // test filling in password-only login
+  const state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "",
+    passValue: "examplepass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  const action = {
+    buttonClick: "ok",
+  };
+  authinfo.username = "";
+  authinfo.password = "";
+  authinfo.realm    = "http://example.com";
+
+  promptDone = handlePrompt(state, action);
+  const isOk = prompter2.promptAuth("channel1", level, authinfo);
+  await promptDone;
+
+  ok(isOk, "Checking dialog return value (accept)");
+  is(authinfo.username, "", "Checking returned username");
+  is(authinfo.password, "examplepass", "Checking returned password");
+});
+
+add_task(async function test_multipleExisting() {
+  // test filling in existing login (undetermined from multiple selection)
+  // user2name/user2pass would also be valid to fill here.
+  const state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "user1name",
+    passValue: "user1pass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  const action = {
+    buttonClick: "ok",
+  };
+  authinfo.username = "";
+  authinfo.password = "";
+  authinfo.realm    = "http://example2.com";
+
+  promptDone = handlePrompt(state, action);
+  const isOk = prompter2.promptAuth("channel2", level, authinfo);
+  await promptDone;
+
+  ok(isOk, "Checking dialog return value (accept)");
+  ok(authinfo.username == "user1name" || authinfo.username == "user2name", "Checking returned username");
+  ok(authinfo.password == "user1pass" || authinfo.password == "user2pass", "Checking returned password");
+});
+
+add_task(async function test_multipleExisting2() {
+  // test filling in existing login (undetermined --> user1)
+  // user2name/user2pass would also be valid to fill here.
+  const state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "user1name",
+    passValue: "user1pass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  // enter one of the known logins, test 504+505 exercise the two possible states.
+  const action = {
+    buttonClick: "ok",
+    textField: "user1name",
+    passField: "user1pass",
+  };
+  authinfo.username = "";
+  authinfo.password = "";
+  authinfo.realm    = "http://example2.com";
+
+  promptDone = handlePrompt(state, action);
+  const isOk = prompter2.promptAuth("channel2", level, authinfo);
+  await promptDone;
+
+  ok(isOk, "Checking dialog return value (accept)");
+  is(authinfo.username, "user1name", "Checking returned username");
+  is(authinfo.password, "user1pass", "Checking returned password");
+});
+
+add_task(async function test_multipleExisting3() {
+  // test filling in existing login (undetermined --> user2)
+  // user2name/user2pass would also be valid to fill here.
+  const state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "user1name",
+    passValue: "user1pass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  // enter one of the known logins, test 504+505 exercise the two possible states.
+  const action = {
+    buttonClick: "ok",
+    textField: "user2name",
+    passField: "user2pass",
+  };
+  authinfo.username = "";
+  authinfo.password = "";
+  authinfo.realm    = "http://example2.com";
+
+  promptDone = handlePrompt(state, action);
+  const isOk = prompter2.promptAuth("channel2", level, authinfo);
+  await promptDone;
+
+  ok(isOk, "Checking dialog return value (accept)");
+  is(authinfo.username, "user2name", "Checking returned username");
+  is(authinfo.password, "user2pass", "Checking returned password");
+});
+
+add_task(async function test_changingMultiple() {
+  // test changing a password (undetermined --> user2 w/ newpass)
+  // user2name/user2pass would also be valid to fill here.
+  const state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "user1name",
+    passValue: "user1pass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  // force to user2, and change the password
+  const action = {
+    buttonClick: "ok",
+    textField: "user2name",
+    passField: "NEWuser2pass",
+  };
+  authinfo.username = "";
+  authinfo.password = "";
+  authinfo.realm    = "http://example2.com";
+
+  promptDone = handlePrompt(state, action);
+  const isOk = prompter2.promptAuth("channel2", level, authinfo);
+  await promptDone;
+
+  ok(isOk, "Checking dialog return value (accept)");
+  is(authinfo.username, "user2name", "Checking returned username");
+  is(authinfo.password, "NEWuser2pass", "Checking returned password");
+});
+
+add_task(async function test_changingMultiple2() {
+  // test changing a password (undetermined --> user2 w/ origpass)
+  // user2name/user2pass would also be valid to fill here.
+  const state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "user1name",
+    passValue: "user1pass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  // force to user2, and change the password back
+  const action = {
+    buttonClick: "ok",
+    textField: "user2name",
+    passField: "user2pass",
+  };
+  authinfo.username = "";
+  authinfo.password = "";
+  authinfo.realm    = "http://example2.com";
+
+  promptDone = handlePrompt(state, action);
+  const isOk = prompter2.promptAuth("channel2", level, authinfo);
+  await promptDone;
+
+  ok(isOk, "Checking dialog return value (accept)");
+  is(authinfo.username, "user2name", "Checking returned username");
+  is(authinfo.password, "user2pass", "Checking returned password");
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_prompt_promptAuth_proxy.html b/toolkit/components/passwordmgr/test/mochitest/test_prompt_promptAuth_proxy.html
new file mode 100644
index 0000000000..6f78d62f1b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_prompt_promptAuth_proxy.html
@@ -0,0 +1,269 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test promptAuth proxy prompts</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="text/javascript" src="../../../prompts/test/prompt_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<div id="content" style="display: none">
+  <iframe id="iframe"></iframe>
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+/* eslint-disable mozilla/use-chromeutils-generateqi */
+
+const LEVEL = Ci.nsIAuthPrompt2.LEVEL_NONE;
+
+let proxyAuthinfo = {
+  username: "",
+  password: "",
+  domain: "",
+
+  flags: Ci.nsIAuthInformation.AUTH_PROXY,
+  authenticationScheme: "basic",
+  realm: "",
+};
+
+// Let prompt_common know what kind of modal type is enabled for auth prompts.
+modalType = authPromptModalType;
+
+let chromeScript = runInParent(() => {
+  const promptFac = Cc[
+    "@mozilla.org/passwordmanager/authpromptfactory;1"
+  ].getService(Ci.nsIPromptFactory);
+
+  let systemPrincipal = Services.scriptSecurityManager.getSystemPrincipal();
+
+  let chromeWin = Services.wm.getMostRecentWindow("navigator:browser");
+  let prompter2 = promptFac.getPrompt(chromeWin, Ci.nsIAuthPrompt2);
+  prompter2.QueryInterface(Ci.nsILoginManagerAuthPrompter).browser =
+    chromeWin.gBrowser.selectedBrowser;
+
+  let mozproxyURL;
+  let proxyChannel;
+
+  addMessageListener("init", () => init());
+
+  addMessageListener("proxyPrompter", function onMessage(msg) {
+    let args = [...msg.args];
+
+    args[0] = proxyChannel;
+    let rv = prompter2[msg.methodName](...args);
+    return {
+      rv,
+      // Send the args back to content so out/inout args can be checked.
+      args: msg.args,
+    };
+  });
+
+  addMessageListener("getTimeLastUsed", async () => {
+    let logins = await Services.logins.searchLoginsAsync({ origin: mozproxyURL, httpRealm: "Proxy Realm"});
+    return logins[0].QueryInterface(Ci.nsILoginMetaInfo).timeLastUsed;
+  });
+
+  function init() {
+    // Need to allow for arbitrary network servers defined in PAC instead of a hardcoded moz-proxy.
+    let pps = Cc["@mozilla.org/network/protocol-proxy-service;1"].getService();
+
+    let channel = Services.io.newChannel(
+      "http://example.com",
+      null,
+      null,
+      null, // aLoadingNode
+      systemPrincipal,
+      null, // aTriggeringPrincipal
+      Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL,
+      Ci.nsIContentPolicy.TYPE_OTHER
+    );
+    pps.asyncResolve(channel, 0, resolveCallback);
+  }
+
+  class ProxyChannelListener {
+    onStartRequest(request) {
+      sendAsyncMessage("initDone");
+    }
+    onStopRequest(request, status) {}
+  }
+
+  async function initLogins(pi) {
+    mozproxyURL = `moz-proxy://${pi.host}:${pi.port}`;
+
+    let proxyLogin = Cc["@mozilla.org/login-manager/loginInfo;1"].createInstance(
+      Ci.nsILoginInfo
+    );
+
+    proxyLogin.init(
+      mozproxyURL,
+      null,
+      "Proxy Realm",
+      "proxuser",
+      "proxpass",
+      "",
+      ""
+    );
+
+    await Services.logins.addLoginAsync(proxyLogin);
+  }
+
+  let resolveCallback = {
+    QueryInterface(iid) {
+      const interfaces = [Ci.nsIProtocolProxyCallback, Ci.nsISupports];
+
+      if (
+        !interfaces.some(function (v) {
+          return iid.equals(v);
+        })
+      ) {
+        throw Components.Exception("", Cr.NS_ERROR_NO_INTERFACE);
+      }
+      return this;
+    },
+
+    async onProxyAvailable(req, uri, pi, status) {
+      await initLogins(pi);
+
+      // I'm cheating a bit here... We should probably do some magic foo to get
+      // something implementing nsIProxiedProtocolHandler and then call
+      // NewProxiedChannel(), so we have something that's definately a proxied
+      // channel. But Mochitests use a proxy for a number of hosts, so just
+      // requesting a normal channel will give us a channel that's proxied.
+      // The proxyChannel needs to move to at least on-modify-request to
+      // have valid ProxyInfo, but we use OnStartRequest during startup()
+      // for simplicity.
+      proxyChannel = Services.io.newChannel(
+        "http://mochi.test:8888",
+        null,
+        null,
+        null, // aLoadingNode
+        systemPrincipal,
+        null, // aTriggeringPrincipal
+        Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL,
+        Ci.nsIContentPolicy.TYPE_OTHER
+      );
+      proxyChannel.asyncOpen(new ProxyChannelListener());
+    },
+  };
+});
+
+let prompter2 = new PrompterProxy(chromeScript);
+
+add_setup(async () => {
+  let initComplete = new Promise((resolve) =>
+    chromeScript.addMessageListener("initDone", resolve)
+  );
+  chromeScript.sendAsyncMessage("init");
+  info("Waiting for startup to complete...");
+  await initComplete;
+});
+
+add_task(async function test_noAutologin() {
+  // test proxy login (default = no autologin), make sure it prompts.
+  let state = {
+    msg:
+      "The proxy moz-proxy://127.0.0.1:8888 is requesting a username and password. The site says: “Proxy Realm”",
+    title: "Authentication Required",
+    textValue: "proxuser",
+    passValue: "proxpass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  let action = {
+    buttonClick: "ok",
+  };
+  proxyAuthinfo.username = "";
+  proxyAuthinfo.password = "";
+  proxyAuthinfo.realm = "Proxy Realm";
+  proxyAuthinfo.flags = Ci.nsIAuthInformation.AUTH_PROXY;
+
+  let time1 = await chromeScript.sendQuery("getTimeLastUsed");
+  promptDone = handlePrompt(state, action);
+  let isOk = prompter2.promptAuth(null, LEVEL, proxyAuthinfo);
+  await promptDone;
+  let time2 = await chromeScript.sendQuery("getTimeLastUsed");
+
+  ok(isOk, "Checking dialog return value (accept)");
+  isnot(time1, time2, "Checking that timeLastUsed was updated");
+  is(proxyAuthinfo.username, "proxuser", "Checking returned username");
+  is(proxyAuthinfo.password, "proxpass", "Checking returned password");
+});
+
+add_task(async function test_autologin() {
+  // test proxy login (with autologin)
+
+  // Enable the autologin pref.
+  await SpecialPowers.pushPrefEnv({
+    set: [["signon.autologin.proxy", true]],
+  });
+
+  proxyAuthinfo.username = "";
+  proxyAuthinfo.password = "";
+  proxyAuthinfo.realm = "Proxy Realm";
+  proxyAuthinfo.flags = Ci.nsIAuthInformation.AUTH_PROXY;
+
+  let time1 = await chromeScript.sendQuery("getTimeLastUsed");
+  let isOk = prompter2.promptAuth(null, LEVEL, proxyAuthinfo);
+  let time2 = await chromeScript.sendQuery("getTimeLastUsed");
+
+  ok(isOk, "Checking dialog return value (accept)");
+  isnot(time1, time2, "Checking that timeLastUsed was updated");
+  is(proxyAuthinfo.username, "proxuser", "Checking returned username");
+  is(proxyAuthinfo.password, "proxpass", "Checking returned password");
+});
+
+add_task(async function test_autologin_incorrect() {
+  // test proxy login (with autologin), ensure it prompts after a failed auth.
+  let state = {
+    msg:
+      "The proxy moz-proxy://127.0.0.1:8888 is requesting a username and password. The site says: “Proxy Realm”",
+    title: "Authentication Required",
+    textValue: "proxuser",
+    passValue: "proxpass",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  let action = {
+    buttonClick: "ok",
+  };
+
+  proxyAuthinfo.username = "";
+  proxyAuthinfo.password = "";
+  proxyAuthinfo.realm = "Proxy Realm";
+  proxyAuthinfo.flags =
+    Ci.nsIAuthInformation.AUTH_PROXY | Ci.nsIAuthInformation.PREVIOUS_FAILED;
+
+  let time1 = await chromeScript.sendQuery("getTimeLastUsed");
+  promptDone = handlePrompt(state, action);
+  let isOk = prompter2.promptAuth(null, LEVEL, proxyAuthinfo);
+  await promptDone;
+  let time2 = await chromeScript.sendQuery("getTimeLastUsed");
+
+  ok(isOk, "Checking dialog return value (accept)");
+  isnot(time1, time2, "Checking that timeLastUsed was updated");
+  is(proxyAuthinfo.username, "proxuser", "Checking returned username");
+  is(proxyAuthinfo.password, "proxpass", "Checking returned password");
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_recipe_login_fields.html b/toolkit/components/passwordmgr/test/mochitest/test_recipe_login_fields.html
new file mode 100644
index 0000000000..818a4e15bf
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_recipe_login_fields.html
@@ -0,0 +1,212 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for recipes overriding login fields</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<script>
+gTestDependsOnDeprecatedLogin = true;
+var chromeScript = runChecksAfterCommonInit();
+
+let fillPromiseResolvers = [];
+
+function waitForFills(fillCount) {
+  let promises = [];
+  while (fillCount--) {
+    let promise = new Promise(resolve => fillPromiseResolvers.push(resolve));
+    promises.push(promise);
+  }
+
+  return Promise.all(promises);
+}
+
+add_setup(async () => {
+  // This test should run without any existing loaded recipes interfering.
+  await resetRecipes();
+
+  if (document.readyState !== "complete") {
+    await new Promise((resolve) => {
+      document.onreadystatechange = () => {
+        if (document.readyState !== "complete") {
+          return;
+        }
+        document.onreadystatechange = null;
+        resolve();
+      };
+    });
+  }
+
+  document.getElementById("content")
+  .addEventListener("input", function handleInputEvent(evt) {
+    let resolve = fillPromiseResolvers.shift();
+    if (!resolve) {
+      ok(false, "Too many fills");
+      return;
+    }
+
+    resolve(evt.target);
+  });
+});
+
+add_task(async function loadUsernamePasswordSelectorRecipes() {
+  await loadRecipes({
+    siteRecipes: [{
+      hosts: ["mochi.test:8888"],
+      usernameSelector: "input[name='uname1']",
+      passwordSelector: "input[name='pword2']",
+    }],
+  });
+});
+
+add_task(async function testOverriddingFields() {
+  // Insert the form dynamically so autofill is triggered after setup above.
+  document.getElementById("content").innerHTML = `
+    <!-- form with recipe for the username and password -->
+      <form id="form1">
+        <input type="text"     name="uname1" data-expected="true">
+        <input type="text"     name="uname2" data-expected="false">
+        <input type="password" name="pword1" data-expected="false">
+        <input type="password" name="pword2" data-expected="true">
+      </form>`;
+
+  let elements = await waitForFills(2);
+  for (let element of elements) {
+    is(element.dataset.expected, "true", `${element.name} was filled`);
+  }
+});
+
+add_task(async function testDefaultHeuristics() {
+  // Insert the form dynamically so autofill is triggered after setup above.
+  document.getElementById("content").innerHTML = `
+    <!-- Fallback to the default heuristics since the selectors don't match -->
+    <form id="form2">
+      <input type="text"     name="uname3" data-expected="false">
+      <input type="text"     name="uname4" data-expected="true">
+      <input type="password" name="pword3" data-expected="true">
+      <input type="password" name="pword4" data-expected="false">
+    </form>`;
+
+  let elements = await waitForFills(2);
+  for (let element of elements) {
+    is(element.dataset.expected, "true", `${element.name} was filled`);
+  }
+});
+
+add_task(async function loadNotUsernameSelectorRecipes() {
+  await resetRecipes();
+  await loadRecipes({
+    siteRecipes: [{
+      hosts: ["mochi.test:8888"],
+      notUsernameSelector: "input[name='not_uname1']",
+    }],
+  });
+});
+
+add_task(async function testNotUsernameField() {
+  document.getElementById("content").innerHTML = `
+    <!-- The field matching notUsernameSelector should be skipped -->
+    <form id="form3">
+      <input type="text"     name="uname5" data-expected="true">
+      <input type="text"     name="not_uname1" data-expected="false">
+      <input type="password" name="pword5" data-expected="true">
+    </form>`;
+
+  let elements = await waitForFills(2);
+  for (let element of elements) {
+    is(element.dataset.expected, "true", `${element.name} was filled`);
+  }
+});
+
+add_task(async function testNotUsernameFieldNoUsername() {
+  document.getElementById("content").innerHTML = `
+    <!-- The field matching notUsernameSelector should be skipped.
+         No username field should be found and filled in this case -->
+    <form id="form4">
+      <input type="text"     name="not_uname1" data-expected="false">
+      <input type="password" name="pword6" data-expected="true">
+    </form>`;
+
+  let elements = await waitForFills(1);
+  for (let element of elements) {
+    is(element.dataset.expected, "true", `${element.name} was filled`);
+  }
+});
+
+add_task(async function loadNotPasswordSelectorRecipes() {
+  await resetRecipes();
+  await loadRecipes({
+    siteRecipes: [{
+      hosts: ["mochi.test:8888"],
+      notPasswordSelector: "input[name='not_pword'], input[name='not_pword2']",
+    }],
+  });
+});
+
+add_task(async function testNotPasswordField() {
+  document.getElementById("content").innerHTML = `
+    <!-- The field matching notPasswordSelector should be skipped -->
+    <form id="form5">
+      <input type="text"     name="uname7" data-expected="true">
+      <input type="password" name="not_pword" data-expected="false">
+      <input type="password" name="pword7" data-expected="true">
+    </form>`;
+
+  let elements = await waitForFills(2);
+  for (let element of elements) {
+    is(element.dataset.expected, "true", `${element.name} was filled`);
+  }
+});
+
+add_task(async function testNotPasswordFieldNoPassword() {
+  document.getElementById("content").innerHTML = `
+    <!-- The field matching notPasswordSelector should be skipped.
+         No username or password field should be found and filled in this case.
+         A dummy form7 is added after so we know when the login manager is done
+         considering filling form6. -->
+    <form id="form6">
+      <input type="text"     name="uname8" data-expected="false">
+      <input type="password" name="not_pword" data-expected="false">
+    </form>
+    <form id="form7">
+      <input type="password" name="pword9" data-expected="true">
+    </form>`;
+
+  let elements = await waitForFills(1);
+  for (let element of elements) {
+    is(element.dataset.expected, "true", `${element.name} was filled`);
+  }
+});
+
+add_task(async function testNotPasswordField_tooManyToOkay() {
+  document.getElementById("content").innerHTML = `
+    <!-- The field matching notPasswordSelector should be skipped so we won't
+         have too many pw fields to handle (3). -->
+    <form id="form8">
+      <input type="text"     name="uname9" data-expected="true">
+      <input type="password" name="not_pword2" data-expected="false">
+      <input type="password" name="not_pword" data-expected="false">
+      <input type="password" name="pword10" data-expected="true">
+      <input type="password" name="pword11" data-expected="false">
+      <input type="password" name="pword12" data-expected="false">
+    </form>`;
+
+  let elements = await waitForFills(2);
+  for (let element of elements) {
+    is(element.dataset.expected, "true", `${element.name} was filled`);
+  }
+});
+
+</script>
+
+<p id="display"></p>
+
+<div id="content">
+  // Forms are inserted dynamically
+</div>
+<pre id="test"></pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_set_stored_logins_during_task.html b/toolkit/components/passwordmgr/test/mochitest/test_set_stored_logins_during_task.html
new file mode 100644
index 0000000000..36db568708
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_set_stored_logins_during_task.html
@@ -0,0 +1,50 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Login Manager Test Helper: setLoginsDuringTest</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+Testing the test helpers `setStoredLoginsDuringTask` and `setStoredLoginsDuringTest`, which prepares the login storage during a test or task.
+
+<script class="testbody" type="text/javascript">
+add_setup(async () => {
+  await setStoredLoginsDuringTest(
+    ["https://example.com", "https://example.com", null, "example.com-user-one", "password", "uname", "pword"],
+    ["https://example.com", "https://example.com", null, "example.com-user-two", "password", "uname", "pword"],
+  );
+});
+
+add_named_task("logins should have been stored during setup", async () => {
+  const logins = await getLogins();
+  is(logins.length, 2, "two logins from setup should have been stored");
+  is(logins[0][3], "example.com-user-one", "Login one should have been restored");
+  is(logins[1][3], "example.com-user-two", "Login two should have been restored");
+});
+
+add_named_task("logins should be overwritten", async () => {
+  await setStoredLoginsDuringTask(
+    ["https://example.com", "https://example.com", null, "example.com-user-three", "password", "uname", "pword"],
+  );
+  const logins = await getLogins();
+  is(logins.length, 1, "logins should have been set to single login");
+  is(logins[0][3], "example.com-user-three", "Login three should have been restored");
+});
+
+add_named_task("logins should get restored", async () => {
+  const logins = await getLogins();
+  is(logins.length, 2, "Logins should have been restored");
+  is(logins[0][3], "example.com-user-one", "Login one should have been restored");
+  is(logins[1][3], "example.com-user-two", "Login two should have been restored");
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_submit_without_field_modifications.html b/toolkit/components/passwordmgr/test/mochitest/test_submit_without_field_modifications.html
new file mode 100644
index 0000000000..c31efe6a98
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_submit_without_field_modifications.html
@@ -0,0 +1,311 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Don't send onFormSubmit message on navigation if the user did not interact
+    with the login fields</title>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+
+<div id="content">
+  <iframe id="loginFrame">
+  </iframe>
+</div>
+
+<pre id="test"></pre>
+<script>
+SimpleTest.requestFlakyTimeout("Giving a chance for the unexpected popup to show");
+
+const EXAMPLE_COM = window.location.origin + "/tests/toolkit/components/passwordmgr/test/mochitest/";
+const PREFILLED_FORM_URL = EXAMPLE_COM + "subtst_prefilled_form.html"
+
+let iframe = document.getElementById("loginFrame");
+
+function waitForLoad() {
+  return new Promise(resolve => {
+    function handleLoad() {
+      iframe.removeEventListener("load", handleLoad);
+      resolve();
+    }
+    iframe.addEventListener("load", handleLoad);
+  });
+}
+
+async function setupWithOneLogin(pageUrl) {
+  let origin = window.location.origin;
+  await setStoredLoginsAsync([origin, origin, null, "user1", "pass1"]);
+
+  let chromeScript = runInParent(async function testSetup() {
+    let logins = await Services.logins.getAllLogins();
+    for (let l of logins) {
+      info("Got login: " + l.username + ", " + l.password);
+    }
+  });
+
+  await setup(pageUrl);
+  return chromeScript;
+}
+
+function resetSavedLogins() {
+  let chromeScript = runInParent(function testTeardown() {
+    Services.logins.removeAllUserFacingLogins();
+  });
+  chromeScript.destroy();
+}
+
+async function setup(pageUrl) {
+  let loadPromise = waitForLoad();
+  let processedFormPromise = promiseFormsProcessed();
+  iframe.src = pageUrl;
+
+  await processedFormPromise;
+  info("initial form processed");
+  await loadPromise;
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    let doc = this.content.document;
+    let link = doc.createElement("a");
+    link.setAttribute("href", "http://mochi.test:8888");
+    doc.body.appendChild(link);
+  });
+}
+
+async function navigateWithoutUserInteraction() {
+  let loadPromise = waitForLoad();
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    let doc = this.content.document;
+    let hadInteracted = doc.userHasInteracted;
+    let target = doc.querySelector("a[href]");
+    if (target) {
+      target.click();
+    } else {
+      target = doc.querySelector("form");
+      target.submit();
+    }
+    is(doc.userHasInteracted, hadInteracted, "document.userHasInteracted shouldn't have changed");
+  });
+  await loadPromise;
+}
+
+async function userInput(selector, value) {
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [selector, value], async function(sel, val) {
+    // use "real" synthesized events rather than setUserInput to ensure
+    // document.userHasInteracted is flipped true
+    let EventUtils = ContentTaskUtils.getEventUtils(content);
+    let target = this.content.document.querySelector(sel);
+    target.focus();
+    target.select();
+    await EventUtils.synthesizeKey("KEY_Backspace", {}, this.content);
+    await EventUtils.sendString(val, this.content);
+    info(
+      `userInput: new target.value: ${target.value}`
+    );
+    target.blur();
+    return Promise.resolve();
+  });
+}
+
+function checkDocumentUserHasInteracted() {
+  return SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    return this.content.document.userHasInteracted;
+  });
+}
+
+add_task(async function test_init() {
+  // For this test, we'll be testing with & without user document interaction.
+  // So we'll reset the pref which dictates the behavior of
+  // LoginFormState._formHasModifiedFields in automation
+  // and ensure all interactions are properly emulated
+  ok(SpecialPowers.getBoolPref("signon.testOnlyUserHasInteractedByPrefValue"), "signon.testOnlyUserHasInteractedByPrefValue should default to true");
+  info("test_init, flipping the signon.testOnlyUserHasInteractedByPrefValue pref");
+  await SpecialPowers.pushPrefEnv({"set": [
+    ["signon.testOnlyUserHasInteractedByPrefValue", false],
+  ]});
+  SimpleTest.registerCleanupFunction(async function cleanup_pref() {
+    await SpecialPowers.popPrefEnv();
+  });
+
+  await SimpleTest.promiseWaitForCondition(() => LoginHelper.testOnlyUserHasInteractedWithDocument === null);
+  is(LoginHelper.testOnlyUserHasInteractedWithDocument, null,
+    "LoginHelper.testOnlyUserHasInteractedWithDocument should be null for this set of tests");
+});
+
+add_task(async function test_no_message_on_navigation() {
+  // If login field values were set by the website, we don't message to save the
+  // login values if the user did not interact with the fields before submiting.
+  await setup(PREFILLED_FORM_URL);
+
+  let submitMessageSent = false;
+  getSubmitMessage().then(value => {
+    submitMessageSent = true;
+  });
+  await navigateWithoutUserInteraction();
+
+  // allow time to pass before concluding no onFormSubmit message was sent
+  await new Promise(res => setTimeout(res, 1000));
+  ok(!submitMessageSent, "onFormSubmit message is not sent on navigation since the login fields were not modified");
+});
+
+add_task(async function test_prefd_off_message_on_navigation() {
+  // Confirm the pref controls capture behavior with non-user-set field values.
+  await SpecialPowers.pushPrefEnv({"set": [
+    ["signon.userInputRequiredToCapture.enabled", false],
+  ]});
+  await setup(PREFILLED_FORM_URL);
+
+  let promiseSubmitMessage = getSubmitMessage();
+  await navigateWithoutUserInteraction();
+  await promiseSubmitMessage;
+  info("onFormSubmit message was sent as expected after navigation");
+
+  SpecialPowers.popPrefEnv();
+});
+
+add_task(async function test_message_with_user_interaction_on_navigation() {
+  await setup(PREFILLED_FORM_URL);
+  await userInput("#form-basic-username", "foo");
+
+  let promiseSubmitMessage = getSubmitMessage();
+  await navigateWithoutUserInteraction();
+  await promiseSubmitMessage;
+  info("onFormSubmit message was sent as expected after user interaction");
+});
+
+add_task(async function test_empty_form_with_input_handler() {
+  await setup(EXAMPLE_COM + "formless_basic.html");
+  await userInput("#form-basic-username", "user");
+  await userInput("#form-basic-password", "pass");
+
+  let promiseSubmitMessage = getSubmitMessage();
+  await navigateWithoutUserInteraction();
+  await promiseSubmitMessage;
+  info("onFormSubmit message was sent as expected after user interaction");
+});
+
+add_task(async function test_no_message_on_autofill_without_user_interaction() {
+  let chromeScript = await setupWithOneLogin(EXAMPLE_COM + "form_basic.html");
+  // Check for autofilled values.
+  await checkLoginFormInFrame(getIframeBrowsingContext(window, 0),
+                                   "form-basic-username", "user1",
+                                   "form-basic-password", "pass1");
+
+  info("LoginHelper.testOnlyUserHasInteractedWithDocument:" +
+      LoginHelper.testOnlyUserHasInteractedWithDocument
+  );
+  ok(!(await checkDocumentUserHasInteracted()), "document.userHasInteracted should be initially false");
+  let submitMessageSent = false;
+  getSubmitMessage().then(value => {
+    submitMessageSent = true;
+  });
+  info("Navigating the page")
+  await navigateWithoutUserInteraction();
+
+  // allow time to pass before concluding no onFormSubmit message was sent
+  await new Promise(res => setTimeout(res, 1000));
+
+  chromeScript.destroy();
+  resetSavedLogins();
+
+  ok(!submitMessageSent, "onFormSubmit message is not sent on navigation since the document had no user interaction");
+});
+
+add_task(async function test_message_on_autofill_with_document_interaction() {
+  // We expect that as long as the form values !== their defaultValues,
+  // any document interaction allows the submit message to be sent
+
+  let chromeScript = await setupWithOneLogin(EXAMPLE_COM + "form_basic.html");
+  // Check for autofilled values.
+  await checkLoginFormInFrame(getIframeBrowsingContext(window, 0),
+                                   "form-basic-username", "user1",
+                                   "form-basic-password", "pass1");
+
+  let userInteracted = await checkDocumentUserHasInteracted();
+  ok(!userInteracted, "document.userHasInteracted should be initially false");
+
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), ["#form-basic-username"], async function(sel) {
+    // Click somewhere in the document to ensure document.userHasInteracted is flipped to true
+    let EventUtils = ContentTaskUtils.getEventUtils(content);
+    let target = this.content.document.querySelector(sel);
+
+    await EventUtils.synthesizeMouseAtCenter(target, {}, this.content);
+  });
+
+  userInteracted = await checkDocumentUserHasInteracted();
+  ok(userInteracted, "After synthesizeMouseAtCenter, document.userHasInteracted should be true");
+
+  let promiseSubmitMessage = getSubmitMessage();
+  await navigateWithoutUserInteraction();
+
+  let { data } = await promiseSubmitMessage;
+  ok(data.autoFilledLoginGuid, "Message was sent with autoFilledLoginGuid");
+  info("Message was sent as expected after document user interaction");
+
+  chromeScript.destroy();
+  resetSavedLogins();
+});
+
+add_task(async function test_message_on_autofill_with_user_interaction() {
+  // Editing a field value causes the submit message to be sent as
+  // there is both document interaction and field modification
+  let chromeScript = await setupWithOneLogin(EXAMPLE_COM + "form_basic.html");
+  // Check for autofilled values.
+  await checkLoginFormInFrame(getIframeBrowsingContext(window, 0),
+                                   "form-basic-username", "user1",
+                                   "form-basic-password", "pass1");
+
+  userInput("#form-basic-username", "newuser");
+  let promiseSubmitMessage = getSubmitMessage();
+  await navigateWithoutUserInteraction();
+
+  let { data } = await promiseSubmitMessage;
+  ok(data.autoFilledLoginGuid, "Message was sent with autoFilledLoginGuid");
+  is(data.usernameField.value, "newuser", "Message was sent with correct usernameField.value");
+  info("Message was sent as expected after user form interaction");
+
+  chromeScript.destroy();
+  resetSavedLogins();
+});
+
+add_task(async function test_no_message_on_user_input_from_other_form() {
+  // ensure input into unrelated fields on the page don't change login form modified-ness
+  await setup(PREFILLED_FORM_URL);
+
+  // Add a form which will not be submitted and an input associated with that form
+  await SpecialPowers.spawn(getIframeBrowsingContext(window), [], function() {
+    let doc = this.content.document;
+    let loginForm = doc.querySelector("form");
+    let fragment = doc.createDocumentFragment();
+    let otherForm = doc.createElement("form");
+    otherForm.id ="otherForm";
+    fragment.appendChild(otherForm);
+
+    let alienField = doc.createElement("input");
+    alienField.id = "alienField";
+    alienField.type = "text"; // not a password field
+    alienField.setAttribute("form", "otherForm");
+    // new field is child of the login, but a member of different non-login form via its .form property
+    loginForm.appendChild(alienField);
+    doc.body.appendChild(fragment);
+  });
+  await userInput("#alienField", "something");
+
+  let submitMessageSent = false;
+  getSubmitMessage().then(data => {
+    info("submit mesage data: " + JSON.stringify(data));
+    submitMessageSent = true;
+  });
+
+  info("submitting the form");
+  await navigateWithoutUserInteraction();
+
+  // allow time to pass before concluding no onFormSubmit message was sent
+  await new Promise(res => setTimeout(res, 1000));
+  ok(!submitMessageSent, "onFormSubmit message is not sent on navigation since no login fields were modified");
+});
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_username_focus.html b/toolkit/components/passwordmgr/test/mochitest/test_username_focus.html
new file mode 100644
index 0000000000..9c2f9d8e89
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_username_focus.html
@@ -0,0 +1,166 @@
+
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test interaction between autocomplete and focus on username fields</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <script type="text/javascript" src="../../../satchel/test/satchel_common.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+<div id="content"></div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+const action1 = "http://username-focus-1";
+const action2 = "http://username-focus-2";
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    [location.origin, action1, null, "testuser1A", "testpass1A", "", ""],
+    [location.origin, action2, null, "testuser2A", "testpass2A", "", ""],
+    [location.origin, action2, null, "testuser2B", "testpass2B", "", ""]
+  );
+});
+
+add_task(async function autofilled() {
+  const form = createLoginForm({ action: action1 });
+
+  info("Username and password already filled so don't show autocomplete");
+  await noPopupBy(() => form.uname.focus());
+
+  form.submit.focus();
+  form.uname.value = "testuser";
+  info("Focus when we don't have an exact match");
+  await popupBy(() => form.uname.focus());
+});
+
+add_task(async function autofilled_prefilled_un() {
+  const form = createLoginForm({
+    action: action1,
+    username: {
+      value: "testuser1A"
+    }
+  });
+
+  info("Username and password already filled so don't show autocomplete");
+  await noPopupBy(() => form.uname.focus());
+
+  form.submit.focus();
+  form.uname.value = "testuser";
+  info("Focus when we don't have an exact match");
+  await popupBy(() => form.uname.focus());
+});
+
+add_task(async function autofilled_focused_dynamic() {
+  const form = createLoginForm({
+    action: action1,
+    password: {
+      type: "not-yet-password"
+    }
+  });
+
+  info("Username and password will be filled while username focused");
+  await noPopupBy(() => form.uname.focus());
+
+  info("triggering autofill");
+  await noPopupBy(() => form.pword.type = "password");
+
+  const popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is closed");
+
+  form.submit.focus();
+  form.pword.value = "test";
+  info("Focus when we don't have an exact match");
+  await popupBy(() => form.uname.focus());
+});
+
+// Begin testing forms that have multiple saved logins
+
+add_task(async function multiple() {
+  const form = createLoginForm({ action: action2 });
+
+  info("Fields not filled due to multiple so autocomplete upon focus");
+  await popupBy(() => form.uname.focus());
+});
+
+add_task(async function multiple_dynamic() {
+  const form = createLoginForm({
+    action: action2,
+    password: {
+      type: "not-yet-password"
+    }
+  });
+
+  info("Fields not filled but username is focused upon marking so open");
+  await noPopupBy(() => form.uname.focus());
+
+  info("triggering _fillForm code");
+  await popupBy(() => form.pword.type = "password");
+});
+
+add_task(async function multiple_prefilled_un1() {
+  const form = createLoginForm({
+    action: action2,
+    username: {
+      value: "testuser2A"
+    }
+  });
+
+  info("Username and password already filled so don't show autocomplete");
+  await noPopupBy(() => form.uname.focus());
+
+  form.submit.focus();
+  form.uname.value = "testuser";
+  info("Focus when we don't have an exact match");
+  await popupBy(() => form.uname.focus());
+});
+
+add_task(async function multiple_prefilled_un2() {
+  const form = createLoginForm({
+    action: action2,
+    username: {
+      value: "testuser2B"
+    }
+  });
+
+  info("Username and password already filled so don't show autocomplete");
+  await noPopupBy(() => form.uname.focus());
+
+  form.submit.focus();
+  form.uname.value = "testuser";
+  info("Focus when we don't have an exact match");
+  await popupBy(() => form.uname.focus());
+});
+
+add_task(async function multiple_prefilled_focused_dynamic() {
+  const form = createLoginForm({
+    action: action2,
+    username: {
+      value: "testuser2B"
+    },
+    password: {
+      type: "not-yet-password"
+    }
+  });
+
+  info("Username and password will be filled while username focused");
+  await noPopupBy(() => form.uname.focus());
+  info("triggering autofill");
+  await noPopupBy(() => form.pword.type = "password");
+
+  let popupState = await getPopupState();
+  is(popupState.open, false, "Check popup is closed");
+
+  form.submit.focus();
+  form.pword.value = "test";
+  info("Focus when we don't have an exact match");
+  await popupBy(() => form.uname.focus());
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_xhr.html b/toolkit/components/passwordmgr/test/mochitest/test_xhr.html
new file mode 100644
index 0000000000..811a2e7759
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_xhr.html
@@ -0,0 +1,164 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for XHR prompts</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <script type="text/javascript" src="../../../prompts/test/prompt_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+Login Manager test: XHR prompt
+<p id="display"></p>
+
+<div id="content" style="display: none">
+  <iframe id="iframe"></iframe>
+</div>
+
+<pre id="test">
+<script class="testbody" type="text/javascript">
+
+/** Test for Login Manager: XHR prompts. **/
+function makeRequest(uri) {
+  return new Promise((resolve, reject) => {
+    let request = new XMLHttpRequest();
+    request.open("GET", uri, true);
+    request.addEventListener("loadend", function onLoadEnd() {
+      let result = xhrLoad(request.responseXML);
+      resolve(result);
+    });
+    request.send(null);
+  });
+}
+
+function xhrLoad(xmlDoc) {
+  // The server echos back the user/pass it received.
+  var username = xmlDoc.getElementById("user").textContent;
+  var password = xmlDoc.getElementById("pass").textContent;
+  var authok = xmlDoc.getElementById("ok").textContent;
+  return {username, password, authok};
+}
+
+// Let prompt_common know what kind of modal type is enabled for auth prompts.
+modalType = authPromptModalType;
+
+let prompterParent = runInParent(() => {
+  const promptFac = Cc["@mozilla.org/passwordmanager/authpromptfactory;1"].
+                    getService(Ci.nsIPromptFactory);
+
+  let chromeWin = Services.wm.getMostRecentWindow("navigator:browser");
+  let prompt = promptFac.getPrompt(chromeWin, Ci.nsIAuthPrompt);
+
+  addMessageListener("proxyPrompter", function onMessage(msg) {
+    let rv = prompt[msg.methodName](...msg.args);
+    return {
+      rv,
+      // Send the args back to content so out/inout args can be checked.
+      args: msg.args,
+    };
+  });
+});
+
+let prompter1 = new PrompterProxy(prompterParent);
+
+add_setup(async () => {
+  await setStoredLoginsAsync(
+    ["http://mochi.test:8888", null, "xhr", "xhruser1", "xhrpass1"],
+    ["http://mochi.test:8888", null, "xhr2", "xhruser2", "xhrpass2"]
+  );
+});
+
+add_task(async function test1() {
+  let state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "xhruser1",
+    passValue: "xhrpass1",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+  let action = {
+    buttonClick: "ok",
+  };
+  let promptDone = handlePrompt(state, action);
+  let requestPromise = makeRequest("authenticate.sjs?user=xhruser1&pass=xhrpass1&realm=xhr");
+  await promptDone;
+  let result = await requestPromise;
+
+  is(result.authok, "PASS", "Checking for successful authentication");
+  is(result.username, "xhruser1", "Checking for username");
+  is(result.password, "xhrpass1", "Checking for password");
+});
+
+add_task(async function test2() {
+  // Test correct parenting, by opening another tab in the foreground,
+  // and making sure the prompt re-focuses the original tab when shown:
+  let newWin = window.open();
+  newWin.focus();
+
+  let state = {
+    msg: "This site is asking you to sign in.",
+    title: "Authentication Required",
+    textValue: "xhruser2",
+    passValue: "xhrpass2",
+    iconClass: "authentication-icon question-icon",
+    titleHidden: true,
+    textHidden: false,
+    passHidden: false,
+    checkHidden: true,
+    checkMsg: "",
+    checked: false,
+    focused: "textField",
+    defButton: "button0",
+  };
+
+  // For window prompts check that the dialog is modal, chrome and dependent;
+  // We can't just check window.opener because that'll be
+  // a content window, which therefore isn't exposed (it'll lie and
+  // be null).
+  if (authPromptModalType === SpecialPowers.Services.prompt.MODAL_TYPE_WINDOW) {
+    state.chrome = true;
+    state.dialog = true;
+    state.chromeDependent = true;
+    state.isWindowModal = true;
+  }
+
+  let action = {
+    buttonClick: "ok",
+  };
+  let promptDone = handlePrompt(state, action);
+  let requestPromise = makeRequest("authenticate.sjs?user=xhruser2&pass=xhrpass2&realm=xhr2");
+  await promptDone;
+  let result = await requestPromise;
+
+  runInParent(() => {
+    // Check that the right tab is focused:
+    let browserWin = Services.wm.getMostRecentWindow("navigator:browser");
+    let spec = browserWin.gBrowser.selectedBrowser.currentURI.spec;
+    assert.ok(spec.startsWith(window.location.origin),
+              `Tab with remote URI (rather than about:blank)
+               should be focused (${spec})`);
+  });
+
+  is(result.authok, "PASS", "Checking for successful authentication");
+  is(result.username, "xhruser2", "Checking for username");
+  is(result.password, "xhrpass2", "Checking for password");
+
+  // Wait for the assert from the parent script to run and send back its reply,
+  // so it's processed before the test ends.
+  await SpecialPowers.executeAfterFlushingMessageQueue();
+
+  newWin.close();
+});
+</script>
+</pre>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/mochitest/test_xhr_2.html b/toolkit/components/passwordmgr/test/mochitest/test_xhr_2.html
new file mode 100644
index 0000000000..16d5e786e0
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/mochitest/test_xhr_2.html
@@ -0,0 +1,56 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=654348
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test XHR auth with user and pass arguments</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="pwmgr_common.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body onload="startTest()">
+<script class="testbody" type="text/javascript">
+
+/**
+ * This test checks we correctly ignore authentication entry
+ * for a subpath and use creds from the URL when provided when XHR
+ * is used with filled user name and password.
+ *
+ * 1. connect authenticate.sjs that excepts user1:pass1 password
+ * 2. connect authenticate.sjs that this time expects differentuser2:pass2 password
+ *    we must use the creds that are provided to the xhr witch are different and expected
+ */
+
+function doxhr(URL, user, pass, code, next) {
+  var xhr = new XMLHttpRequest();
+  if (user && pass) {
+    xhr.open("POST", URL, true, user, pass);
+  } else {
+    xhr.open("POST", URL, true);
+  }
+  xhr.onload = function() {
+    is(xhr.status, code, "expected response code " + code);
+    next();
+  };
+  xhr.onerror = function() {
+    ok(false, "request passed");
+    finishTest();
+  };
+  xhr.send();
+}
+
+function startTest() {
+  doxhr("authenticate.sjs?user=dummy&pass=pass1&realm=realm1&formauth=1", "dummy", "dummy", 403, function() {
+    doxhr("authenticate.sjs?user=dummy&pass=pass1&realm=realm1&formauth=1", "dummy", "pass1", 200, finishTest);
+  });
+}
+
+function finishTest() {
+  SimpleTest.finish();
+}
+
+</script>
+</body>
+</html>
diff --git a/toolkit/components/passwordmgr/test/unit/data/corruptDB.sqlite b/toolkit/components/passwordmgr/test/unit/data/corruptDB.sqlite
new file mode 100644
index 0000000000..b234246cac
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/data/corruptDB.sqlite
diff --git a/toolkit/components/passwordmgr/test/unit/data/key4.db b/toolkit/components/passwordmgr/test/unit/data/key4.db
new file mode 100644
index 0000000000..b75a14aa8e
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/data/key4.db
diff --git a/toolkit/components/passwordmgr/test/unit/head.js b/toolkit/components/passwordmgr/test/unit/head.js
new file mode 100644
index 0000000000..8c2dc53f66
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/head.js
@@ -0,0 +1,134 @@
+/**
+ * Provides infrastructure for automated login components tests.
+ */
+
+"use strict";
+
+// Globals
+
+const { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+const { XPCOMUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/XPCOMUtils.sys.mjs"
+);
+const { LoginRecipesContent, LoginRecipesParent } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginRecipes.sys.mjs"
+);
+const { LoginHelper } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginHelper.sys.mjs"
+);
+const { FileTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/FileTestUtils.sys.mjs"
+);
+const { LoginTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/LoginTestUtils.sys.mjs"
+);
+const { MockDocument } = ChromeUtils.importESModule(
+  "resource://testing-common/MockDocument.sys.mjs"
+);
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(this, {
+  DownloadPaths: "resource://gre/modules/DownloadPaths.sys.mjs",
+  FileUtils: "resource://gre/modules/FileUtils.sys.mjs",
+});
+
+const LoginInfo = Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  "nsILoginInfo",
+  "init"
+);
+
+const TestData = LoginTestUtils.testData;
+const newPropertyBag = LoginHelper.newPropertyBag;
+
+const NEW_PASSWORD_HEURISTIC_ENABLED_PREF =
+  "signon.generation.confidenceThreshold";
+const RELATED_REALMS_ENABLED_PREF = "signon.relatedRealms.enabled";
+const IMPROVED_PASSWORD_RULES_PREF = "signon.improvedPasswordRules.enabled";
+/**
+ * All the tests are implemented with add_task, this starts them automatically.
+ */
+function run_test() {
+  do_get_profile();
+  run_next_test();
+}
+
+// Global helpers
+
+/**
+ * Returns a reference to a temporary file that is guaranteed not to exist and
+ * is cleaned up later. See FileTestUtils.getTempFile for details.
+ */
+function getTempFile(leafName) {
+  return FileTestUtils.getTempFile(leafName);
+}
+
+const RecipeHelpers = {
+  initNewParent() {
+    return new LoginRecipesParent({ defaults: null }).initializationPromise;
+  },
+};
+
+// Initialization functions common to all tests
+
+add_setup(async function test_common_initialize() {
+  // Before initializing the service for the first time, we should copy the key
+  // file required to decrypt the logins contained in the SQLite databases used
+  // by migration tests.  This file is not required for the other tests.
+  const keyDBName = "key4.db";
+  await IOUtils.copy(
+    do_get_file(`data/${keyDBName}`).path,
+    PathUtils.join(PathUtils.profileDir, keyDBName)
+  );
+
+  // Ensure that the service and the storage module are initialized.
+  await Services.logins.initializationPromise;
+  Services.prefs.setBoolPref(RELATED_REALMS_ENABLED_PREF, true);
+  if (LoginHelper.relatedRealmsEnabled) {
+    // Ensure that there is a mocked Remote Settings database for the
+    // "websites-with-shared-credential-backends" collection
+    await LoginTestUtils.remoteSettings.setupWebsitesWithSharedCredentials();
+  }
+});
+
+add_setup(async function test_common_prefs() {
+  Services.prefs.setStringPref(NEW_PASSWORD_HEURISTIC_ENABLED_PREF, "0.75");
+});
+
+/**
+ * Compare two FormLike to see if they represent the same information. Elements
+ * are compared using their @id attribute.
+ */
+function formLikeEqual(a, b) {
+  Assert.strictEqual(
+    Object.keys(a).length,
+    Object.keys(b).length,
+    "Check the formLikes have the same number of properties"
+  );
+
+  for (let propName of Object.keys(a)) {
+    if (propName == "elements") {
+      Assert.strictEqual(
+        a.elements.length,
+        b.elements.length,
+        "Check element count"
+      );
+      for (let i = 0; i < a.elements.length; i++) {
+        Assert.strictEqual(
+          a.elements[i].id,
+          b.elements[i].id,
+          "Check element " + i + " id"
+        );
+      }
+      continue;
+    }
+    Assert.strictEqual(
+      a[propName],
+      b[propName],
+      "Compare formLike " + propName + " property"
+    );
+  }
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_CSVParser.js b/toolkit/components/passwordmgr/test/unit/test_CSVParser.js
new file mode 100644
index 0000000000..d680d8daf2
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_CSVParser.js
@@ -0,0 +1,254 @@
+/* Any copyright is dedicated to the Public Domain.
+http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const { CSV } = ChromeUtils.importESModule(
+  "resource://gre/modules/CSV.sys.mjs"
+);
+
+const TEST_CASES = [
+  {
+    description:
+      "string with fields with no special characters gets parsed correctly",
+    csvString: `
+url,username,password
+https://example.com/,testusername,testpassword
+`,
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [
+      {
+        url: "https://example.com/",
+        username: "testusername",
+        password: "testpassword",
+      },
+    ],
+    delimiter: ",",
+    throwsError: false,
+  },
+  {
+    description:
+      "string with fields enclosed in quotes with no special characters gets parsed correctly",
+    csvString: `
+"url","username","password"
+"https://example.com/","testusername","testpassword"
+`,
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [
+      {
+        url: "https://example.com/",
+        username: "testusername",
+        password: "testpassword",
+      },
+    ],
+    delimiter: ",",
+    throwsError: false,
+  },
+  {
+    description: "empty fields gets parsed correctly",
+    csvString: `
+"url","username","password"
+"https://example.com/","",""
+`,
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [
+      {
+        url: "https://example.com/",
+        username: "",
+        password: "",
+      },
+    ],
+    delimiter: ",",
+    throwsError: false,
+  },
+  {
+    description: "string with commas in fields gets parsed correctly",
+    csvString: `
+url,username,password
+https://example.com/,"test,usern,ame","tes,,tpassword"
+`,
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [
+      {
+        url: "https://example.com/",
+        username: "test,usern,ame",
+        password: "tes,,tpassword",
+      },
+    ],
+    delimiter: ",",
+    throwsError: false,
+  },
+  {
+    description: "string with line break in fields gets parsed correctly",
+    csvString: `
+url,username,password
+https://example.com/,"test\nusername","\ntestpass\n\nword"
+`,
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [
+      {
+        url: "https://example.com/",
+        username: "test\nusername",
+        password: "\ntestpass\n\nword",
+      },
+    ],
+    delimiter: ",",
+    throwsError: false,
+  },
+  {
+    description: "string with quotation mark in fields gets parsed correctly",
+    csvString: `
+url,username,password
+https://example.com/,"testusern""ame","test""""pass""word"
+`,
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [
+      {
+        url: "https://example.com/",
+        username: 'testusern"ame',
+        password: 'test""pass"word',
+      },
+    ],
+    delimiter: ",",
+    throwsError: false,
+  },
+  {
+    description: "tsv string with tab as delimiter gets parsed correctly",
+    csvString: `
+url\tusername\tpassword
+https://example.com/\ttestusername\ttestpassword
+`,
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [
+      {
+        url: "https://example.com/",
+        username: "testusername",
+        password: "testpassword",
+      },
+    ],
+    delimiter: "\t",
+    throwsError: false,
+  },
+  {
+    description: "string with CR LF as line breaks gets parsed correctly",
+    csvString:
+      "url,username,password\r\nhttps://example.com/,testusername,testpassword\r\n",
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [
+      {
+        url: "https://example.com/",
+        username: "testusername",
+        password: "testpassword",
+      },
+    ],
+    delimiter: ",",
+    throwsError: false,
+  },
+  {
+    description:
+      "string without line break at the end of the file gets parsed correctly",
+    csvString: `
+url,username,password
+https://example.com/,testusername,testpassword`,
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [
+      {
+        url: "https://example.com/",
+        username: "testusername",
+        password: "testpassword",
+      },
+    ],
+    delimiter: ",",
+    throwsError: false,
+  },
+  {
+    description:
+      "multiple line breaks at the beginning, in the middle or at the end of a string are trimmed and not parsed as empty rows",
+    csvString: `
+\r\r
+url,username,password
+\n\n
+https://example.com/,testusername,testpassword
+\n\r
+`,
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [
+      {
+        url: "https://example.com/",
+        username: "testusername",
+        password: "testpassword",
+      },
+    ],
+    delimiter: ",",
+    throwsError: false,
+  },
+  {
+    description:
+      "throws error when after a field, that is enclosed in quotes, follow any invalid characters (doesn't follow csv standard - RFC 4180)",
+    csvString: `
+  url,username,password
+  https://example.com/,"testusername"outside,testpassword
+  `,
+    delimiter: ",",
+    throwsError: true,
+  },
+  {
+    description:
+      "throws error when the closing quotation mark for a field is missing (doesn't follow csv standard - RFC 4180)",
+    csvString: `
+url,"username,password
+https://example.com/,testusername,testpassword
+`,
+    delimiter: ",",
+    throwsError: true,
+  },
+  {
+    description:
+      "parsing empty csv file results in empty header line and empty parsedLines",
+    csvString: "",
+    expectedHeaderLine: [],
+    expectedParsedLines: [],
+    delimiter: ",",
+    throwsError: false,
+  },
+  {
+    description:
+      "parsing csv file with only header line results in empty parsedLines",
+    csvString: "url,username,password\n",
+    expectedHeaderLine: ["url", "username", "password"],
+    expectedParsedLines: [],
+    delimiter: ",",
+    throwsError: false,
+  },
+];
+
+async function parseCSVStringAndValidateResult(test) {
+  info(`Test case: ${test.description}`);
+  if (test.throwsError) {
+    Assert.throws(
+      () => CSV.parse(test.csvString, test.delimiter),
+      /Stopped parsing because of wrong csv format/
+    );
+  } else {
+    let [resultHeaderLine, resultParsedLines] = CSV.parse(
+      test.csvString,
+      test.delimiter
+    );
+    Assert.deepEqual(
+      resultHeaderLine,
+      test.expectedHeaderLine,
+      "Header line check"
+    );
+    Assert.deepEqual(
+      resultParsedLines,
+      test.expectedParsedLines,
+      "Parsed lines check"
+    );
+  }
+}
+
+add_task(function test_csv_parsing_results() {
+  TEST_CASES.forEach(testCase => {
+    parseCSVStringAndValidateResult(testCase);
+  });
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_doAutocompleteSearch.js b/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_doAutocompleteSearch.js
new file mode 100644
index 0000000000..2e182a7064
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_doAutocompleteSearch.js
@@ -0,0 +1,148 @@
+/**
+ * Test LoginManagerParent.doAutocompleteSearch()
+ */
+
+"use strict";
+
+const { sinon } = ChromeUtils.importESModule(
+  "resource://testing-common/Sinon.sys.mjs"
+);
+const { LoginManagerParent } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerParent.sys.mjs"
+);
+
+// new-password to the happy path
+const NEW_PASSWORD_TEMPLATE_ARG = {
+  actionOrigin: "https://mozilla.org",
+  searchString: "",
+  previousResult: null,
+  requestId: "foo",
+  hasBeenTypePassword: true,
+  isSecure: true,
+  isProbablyANewPasswordField: true,
+};
+
+add_setup(async () => {
+  Services.prefs.setBoolPref("signon.generation.available", true);
+  Services.prefs.setBoolPref("signon.generation.enabled", true);
+
+  await LoginTestUtils.remoteSettings.setupImprovedPasswordRules();
+
+  sinon
+    .stub(LoginManagerParent._browsingContextGlobal, "get")
+    .withArgs(123)
+    .callsFake(() => {
+      return {
+        currentWindowGlobal: {
+          documentPrincipal:
+            Services.scriptSecurityManager.createContentPrincipalFromOrigin(
+              "https://www.example.com^userContextId=1"
+            ),
+          documentURI: Services.io.newURI("https://www.example.com"),
+        },
+      };
+    });
+});
+
+add_task(async function test_generated_noLogins() {
+  let LMP = new LoginManagerParent();
+  LMP.useBrowsingContext(123);
+
+  Assert.ok(LMP.doAutocompleteSearch, "doAutocompleteSearch exists");
+
+  let result1 = await LMP.doAutocompleteSearch(
+    "https://example.com",
+    NEW_PASSWORD_TEMPLATE_ARG
+  );
+  equal(result1.logins.length, 0, "no logins");
+  Assert.ok(result1.generatedPassword, "has a generated password");
+  equal(result1.generatedPassword.length, 15, "generated password length");
+  Assert.ok(
+    result1.willAutoSaveGeneratedPassword,
+    "will auto-save when storage is empty"
+  );
+
+  info("repeat the search and ensure the same password was used");
+  let result2 = await LMP.doAutocompleteSearch(
+    "https://example.com",
+    NEW_PASSWORD_TEMPLATE_ARG
+  );
+  equal(result2.logins.length, 0, "no logins");
+  equal(
+    result2.generatedPassword,
+    result1.generatedPassword,
+    "same generated password"
+  );
+  Assert.ok(
+    result1.willAutoSaveGeneratedPassword,
+    "will auto-save when storage is still empty"
+  );
+
+  info("Check cases where a password shouldn't be generated");
+
+  let result3 = await LMP.doAutocompleteSearch("https://example.com", {
+    ...NEW_PASSWORD_TEMPLATE_ARG,
+    ...{
+      hasBeenTypePassword: false,
+      isProbablyANewPasswordField: false,
+    },
+  });
+  equal(
+    result3.generatedPassword,
+    null,
+    "no generated password when not a pw. field"
+  );
+
+  let result4 = await LMP.doAutocompleteSearch("https://example.com", {
+    ...NEW_PASSWORD_TEMPLATE_ARG,
+    ...{
+      // This is false when there is no autocomplete="new-password" attribute &&
+      // LoginAutoComplete.isProbablyANewPasswordField returns false
+      isProbablyANewPasswordField: false,
+    },
+  });
+  equal(
+    result4.generatedPassword,
+    null,
+    "no generated password when isProbablyANewPasswordField is false"
+  );
+
+  LMP.useBrowsingContext(999);
+  let result5 = await LMP.doAutocompleteSearch("https://example.com", {
+    ...NEW_PASSWORD_TEMPLATE_ARG,
+  });
+  equal(
+    result5.generatedPassword,
+    null,
+    "no generated password with a missing browsingContextId"
+  );
+});
+
+add_task(async function test_generated_emptyUsernameSavedLogin() {
+  info("Test with a login that will prevent auto-saving");
+  await LoginTestUtils.addLogin({
+    username: "",
+    password: "my-saved-password",
+    origin: "https://example.com",
+    formActionOrigin: NEW_PASSWORD_TEMPLATE_ARG.actionOrigin,
+  });
+
+  let LMP = new LoginManagerParent();
+  LMP.useBrowsingContext(123);
+
+  Assert.ok(LMP.doAutocompleteSearch, "doAutocompleteSearch exists");
+
+  let result1 = await LMP.doAutocompleteSearch(
+    "https://example.com",
+    NEW_PASSWORD_TEMPLATE_ARG
+  );
+  equal(result1.logins.length, 1, "1 login");
+  Assert.ok(result1.generatedPassword, "has a generated password");
+  equal(result1.generatedPassword.length, 15, "generated password length");
+  Assert.ok(
+    !result1.willAutoSaveGeneratedPassword,
+    "won't auto-save when an empty-username match is found"
+  );
+
+  LoginTestUtils.clearData();
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_getGeneratedPassword.js b/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_getGeneratedPassword.js
new file mode 100644
index 0000000000..72503723b8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_getGeneratedPassword.js
@@ -0,0 +1,176 @@
+/**
+ * Test LoginManagerParent.getGeneratedPassword()
+ */
+
+"use strict";
+
+const { sinon } = ChromeUtils.importESModule(
+  "resource://testing-common/Sinon.sys.mjs"
+);
+const { LoginManagerParent } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerParent.sys.mjs"
+);
+
+function simulateNavigationInTheFrame(newOrigin) {
+  LoginManagerParent._browsingContextGlobal.get.restore();
+  sinon
+    .stub(LoginManagerParent._browsingContextGlobal, "get")
+    .withArgs(99)
+    .callsFake(() => {
+      return {
+        currentWindowGlobal: {
+          documentPrincipal:
+            Services.scriptSecurityManager.createContentPrincipalFromOrigin(
+              `https://${newOrigin}^userContextId=2`
+            ),
+          documentURI: Services.io.newURI("https://www.example.com"),
+        },
+      };
+    });
+}
+
+add_task(async function test_getGeneratedPassword() {
+  // Force the feature to be enabled.
+  Services.prefs.setBoolPref("signon.generation.available", true);
+  Services.prefs.setBoolPref("signon.generation.enabled", true);
+
+  // Setup the improved rules collection since the improved password rules
+  // pref is on by default. Otherwise any interaciton with LMP.getGeneratedPassword()
+  // will take a long time to complete
+  if (LoginHelper.improvedPasswordRulesEnabled) {
+    await LoginTestUtils.remoteSettings.setupImprovedPasswordRules();
+  }
+
+  let LMP = new LoginManagerParent();
+  LMP.useBrowsingContext(99);
+
+  Assert.ok(LMP.getGeneratedPassword, "LMP.getGeneratedPassword exists");
+  equal(
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().size,
+    0,
+    "Empty cache to start"
+  );
+
+  equal(await LMP.getGeneratedPassword(), null, "Null with no BrowsingContext");
+
+  Assert.ok(
+    LoginManagerParent._browsingContextGlobal,
+    "Check _browsingContextGlobal exists"
+  );
+  Assert.ok(
+    !LoginManagerParent._browsingContextGlobal.get(99),
+    "BrowsingContext 99 shouldn't exist yet"
+  );
+  info("Stubbing BrowsingContext.get(99)");
+  sinon
+    .stub(LoginManagerParent._browsingContextGlobal, "get")
+    .withArgs(99)
+    .callsFake(() => {
+      return {
+        currentWindowGlobal: {
+          documentPrincipal:
+            Services.scriptSecurityManager.createContentPrincipalFromOrigin(
+              "https://www.example.com^userContextId=6"
+            ),
+          documentURI: Services.io.newURI("https://www.example.com"),
+        },
+      };
+    });
+  Assert.ok(
+    LoginManagerParent._browsingContextGlobal.get(99),
+    "Checking BrowsingContext.get(99) stub"
+  );
+  let password1 = await LMP.getGeneratedPassword();
+  notEqual(password1, null, "Check password was returned");
+  equal(
+    password1.length,
+    LoginTestUtils.generation.LENGTH,
+    "Check password length"
+  );
+  equal(
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().size,
+    1,
+    "1 added to cache"
+  );
+  equal(
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+      "https://www.example.com^userContextId=6"
+    ).value,
+    password1,
+    "Cache key and value"
+  );
+  let password2 = await LMP.getGeneratedPassword();
+  equal(
+    password1,
+    password2,
+    "Same password should be returned for the same origin"
+  );
+
+  // Updating autosaved login to have username will reset generated password
+  const autoSavedLogin = await LoginTestUtils.addLogin({
+    origin: "https://www.example.com^userContextId=6",
+    username: "",
+    password: password1,
+  });
+  const updatedLogin = autoSavedLogin.clone();
+  updatedLogin.username = "anyone";
+  await LoginTestUtils.modifyLogin(autoSavedLogin, updatedLogin);
+  password2 = await LMP.getGeneratedPassword();
+  notEqual(
+    password1,
+    password2,
+    "New password should be returned for the same origin after login saved"
+  );
+
+  simulateNavigationInTheFrame("www.mozilla.org");
+  let password3 = await LMP.getGeneratedPassword();
+  notEqual(
+    password2,
+    password3,
+    "Different password for a different origin for the same BC"
+  );
+  equal(
+    password3.length,
+    LoginTestUtils.generation.LENGTH,
+    "Check password3 length"
+  );
+
+  simulateNavigationInTheFrame("bank.biz");
+  let password4 = await LMP.getGeneratedPassword({ inputMaxLength: 5 });
+  notEqual(
+    password4,
+    password2,
+    "Different password for a different origin for the same BC"
+  );
+  notEqual(
+    password4,
+    password3,
+    "Different password for a different origin for the same BC"
+  );
+  equal(password4.length, 5, "password4 length is limited by input.maxLength");
+
+  info("Now checks cases where null should be returned");
+
+  Services.prefs.setBoolPref("signon.rememberSignons", false);
+  equal(
+    await LMP.getGeneratedPassword(),
+    null,
+    "Prevented when pwmgr disabled"
+  );
+  Services.prefs.setBoolPref("signon.rememberSignons", true);
+
+  Services.prefs.setBoolPref("signon.generation.available", false);
+  equal(await LMP.getGeneratedPassword(), null, "Prevented when unavailable");
+  Services.prefs.setBoolPref("signon.generation.available", true);
+
+  Services.prefs.setBoolPref("signon.generation.enabled", false);
+  equal(await LMP.getGeneratedPassword(), null, "Prevented when disabled");
+  Services.prefs.setBoolPref("signon.generation.enabled", true);
+
+  LMP.useBrowsingContext(123);
+  equal(
+    await LMP.getGeneratedPassword(),
+    null,
+    "Prevented when browsingContext is missing"
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_onPasswordEditedOrGenerated.js b/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_onPasswordEditedOrGenerated.js
new file mode 100644
index 0000000000..bf665faaed
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_onPasswordEditedOrGenerated.js
@@ -0,0 +1,1126 @@
+/**
+ * Test LoginManagerParent._onPasswordEditedOrGenerated()
+ */
+
+"use strict";
+
+const { sinon } = ChromeUtils.importESModule(
+  "resource://testing-common/Sinon.sys.mjs"
+);
+const { LoginManagerParent } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerParent.sys.mjs"
+);
+const { LoginManagerPrompter } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerPrompter.sys.mjs"
+);
+
+const { TestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/TestUtils.sys.mjs"
+);
+const loginTemplate = Object.freeze({
+  origin: "https://www.example.com",
+  formActionOrigin: "https://www.mozilla.org",
+});
+
+let LMP = new LoginManagerParent();
+
+function stubPrompter() {
+  let fakePromptToSavePassword = sinon.stub();
+  let fakePromptToChangePassword = sinon.stub();
+  sinon.stub(LMP, "_getPrompter").callsFake(() => {
+    return {
+      promptToSavePassword: fakePromptToSavePassword,
+      promptToChangePassword: fakePromptToChangePassword,
+    };
+  });
+  LMP._getPrompter().promptToSavePassword();
+  LMP._getPrompter().promptToChangePassword();
+  Assert.ok(LMP._getPrompter.calledTwice, "Checking _getPrompter stub");
+  Assert.ok(
+    fakePromptToSavePassword.calledOnce,
+    "Checking fakePromptToSavePassword stub"
+  );
+  Assert.ok(
+    fakePromptToChangePassword.calledOnce,
+    "Checking fakePromptToChangePassword stub"
+  );
+  function resetPrompterHistory() {
+    LMP._getPrompter.resetHistory();
+    fakePromptToSavePassword.resetHistory();
+    fakePromptToChangePassword.resetHistory();
+  }
+  function restorePrompter() {
+    LMP._getPrompter.restore();
+  }
+  resetPrompterHistory();
+  return {
+    fakePromptToSavePassword,
+    fakePromptToChangePassword,
+    resetPrompterHistory,
+    restorePrompter,
+  };
+}
+
+async function stubGeneratedPasswordForBrowsingContextId(id) {
+  Assert.ok(
+    LoginManagerParent._browsingContextGlobal,
+    "Check _browsingContextGlobal exists"
+  );
+  Assert.ok(
+    !LoginManagerParent._browsingContextGlobal.get(id),
+    `BrowsingContext ${id} shouldn't exist yet`
+  );
+  info(`Stubbing BrowsingContext.get(${id})`);
+  let stub = sinon
+    .stub(LoginManagerParent._browsingContextGlobal, "get")
+    .withArgs(id)
+    .callsFake(() => {
+      return {
+        currentWindowGlobal: {
+          documentPrincipal:
+            Services.scriptSecurityManager.createContentPrincipalFromOrigin(
+              "https://www.example.com^userContextId=6"
+            ),
+          documentURI: Services.io.newURI("https://www.example.com"),
+        },
+        get embedderElement() {
+          info("returning embedderElement");
+          let browser = MockDocument.createTestDocument(
+            "chrome://browser/content/browser.xhtml",
+            `<box xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+              <browser></browser>
+             </box>`,
+            "application/xml",
+            true
+          ).querySelector("browser");
+          MockDocument.mockBrowsingContextProperty(browser, this);
+          return browser;
+        },
+        get top() {
+          return this;
+        },
+      };
+    });
+  Assert.ok(
+    LoginManagerParent._browsingContextGlobal.get(id),
+    `Checking BrowsingContext.get(${id}) stub`
+  );
+
+  const generatedPassword = await LMP.getGeneratedPassword();
+  notEqual(generatedPassword, null, "Check password was returned");
+  equal(
+    generatedPassword.length,
+    LoginTestUtils.generation.LENGTH,
+    "Check password length"
+  );
+  equal(
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().size,
+    1,
+    "1 added to cache"
+  );
+  equal(
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+      "https://www.example.com^userContextId=6"
+    ).value,
+    generatedPassword,
+    "Cache key and value"
+  );
+  LoginManagerParent._browsingContextGlobal.get.resetHistory();
+
+  return {
+    stub,
+    generatedPassword,
+  };
+}
+
+function checkEditTelemetryRecorded(expectedCount, msg) {
+  info("Check that expected telemetry event was recorded");
+  const snapshot = Services.telemetry.snapshotEvents(
+    Ci.nsITelemetry.DATASET_PRERELEASE_CHANNELS,
+    false
+  );
+  let resultsCount = 0;
+  if ("parent" in snapshot) {
+    const telemetryProps = Object.freeze({
+      category: "pwmgr",
+      method: "filled_field_edited",
+      object: "generatedpassword",
+    });
+    const results = snapshot.parent.filter(
+      ([time, category, method, object]) => {
+        return (
+          category === telemetryProps.category &&
+          method === telemetryProps.method &&
+          object === telemetryProps.object
+        );
+      }
+    );
+    resultsCount = results.length;
+  }
+  equal(
+    resultsCount,
+    expectedCount,
+    "Check count of pwmgr.filled_field_edited for generatedpassword: " + msg
+  );
+}
+
+async function startTestConditions(contextId) {
+  LMP.useBrowsingContext(contextId);
+
+  Assert.ok(
+    LMP._onPasswordEditedOrGenerated,
+    "LMP._onPasswordEditedOrGenerated exists"
+  );
+  equal(await LMP.getGeneratedPassword(), null, "Null with no BrowsingContext");
+  equal(
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().size,
+    0,
+    "Empty cache to start"
+  );
+  equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should have no saved logins at the start of the test"
+  );
+}
+
+/*
+ * Compare login details excluding usernameField and passwordField
+ */
+function assertLoginProperties(actualLogin, expected) {
+  equal(actualLogin.origin, expected.origin, "Compare origin");
+  equal(
+    actualLogin.formActionOrigin,
+    expected.formActionOrigin,
+    "Compare formActionOrigin"
+  );
+  equal(actualLogin.httpRealm, expected.httpRealm, "Compare httpRealm");
+  equal(actualLogin.username, expected.username, "Compare username");
+  equal(actualLogin.password, expected.password, "Compare password");
+}
+
+add_setup(async () => {
+  // Get a profile for storage.
+  do_get_profile();
+
+  // Force the feature to be enabled.
+  Services.prefs.setBoolPref("signon.generation.available", true);
+  Services.prefs.setBoolPref("signon.generation.enabled", true);
+  await LoginTestUtils.remoteSettings.setupImprovedPasswordRules();
+});
+
+add_task(async function test_onPasswordEditedOrGenerated_generatedPassword() {
+  await startTestConditions(99);
+  let { generatedPassword } = await stubGeneratedPasswordForBrowsingContextId(
+    99
+  );
+  let { fakePromptToChangePassword, restorePrompter } = stubPrompter();
+  let rootBrowser = LMP.getRootBrowser();
+
+  let storageChangedPromised = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    (_, data) => data == "addLogin"
+  );
+
+  equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should have no saved logins at the start of the test"
+  );
+
+  await LMP._onPasswordEditedOrGenerated(
+    rootBrowser,
+    "https://www.example.com",
+    {
+      browsingContextId: 99,
+      formActionOrigin: "https://www.mozilla.org",
+      newPasswordField: { value: generatedPassword },
+      usernameField: { value: "someusername" },
+      triggeredByFillingGenerated: true,
+    }
+  );
+
+  let [login] = await storageChangedPromised;
+  let expected = new LoginInfo(
+    "https://www.example.com",
+    "https://www.mozilla.org",
+    null,
+    "", // verify we don't include the username when auto-saving a login
+    generatedPassword
+  );
+
+  Assert.ok(login.equals(expected), "Check added login");
+  Assert.ok(LMP._getPrompter.calledOnce, "Checking _getPrompter was called");
+  Assert.ok(
+    fakePromptToChangePassword.calledOnce,
+    "Checking promptToChangePassword was called"
+  );
+  Assert.ok(
+    fakePromptToChangePassword.getCall(0).args[3],
+    "promptToChangePassword had a truthy 'dismissed' argument"
+  );
+  Assert.ok(
+    fakePromptToChangePassword.getCall(0).args[4],
+    "promptToChangePassword had a truthy 'notifySaved' argument"
+  );
+
+  info("Edit the password");
+  const newPassword = generatedPassword + "🔥";
+  storageChangedPromised = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    (_, data) => data == "modifyLogin"
+  );
+  await LMP._onPasswordEditedOrGenerated(
+    rootBrowser,
+    "https://www.example.com",
+    {
+      browsingContextId: 99,
+      formActionOrigin: "https://www.mozilla.org",
+      newPasswordField: { value: newPassword },
+      usernameField: { value: "someusername" },
+      triggeredByFillingGenerated: true,
+    }
+  );
+  let generatedPW =
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+      "https://www.example.com^userContextId=6"
+    );
+  Assert.ok(generatedPW.edited, "Cached edited boolean should be true");
+  equal(generatedPW.value, newPassword, "Cached password should be updated");
+  // login metadata should be updated
+  let [dataArray] = await storageChangedPromised;
+  login = dataArray.queryElementAt(1, Ci.nsILoginInfo);
+  expected.password = newPassword;
+  Assert.ok(login.equals(expected), "Check updated login");
+  equal(
+    (await Services.logins.getAllLogins()).length,
+    1,
+    "Should have 1 saved login still"
+  );
+
+  info(
+    "Simulate a second edit to check that the telemetry event for the first edit is not recorded twice"
+  );
+  const newerPassword = newPassword + "🦊";
+  storageChangedPromised = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    (_, data) => data == "modifyLogin"
+  );
+  await LMP._onPasswordEditedOrGenerated(
+    rootBrowser,
+    "https://www.example.com",
+    {
+      browsingContextId: 99,
+      formActionOrigin: "https://www.mozilla.org",
+      newPasswordField: { value: newerPassword },
+      usernameField: { value: "someusername" },
+      triggeredByFillingGenerated: true,
+    }
+  );
+  generatedPW = LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+    "https://www.example.com^userContextId=6"
+  );
+  Assert.ok(generatedPW.edited, "Cached edited state should remain true");
+  equal(generatedPW.value, newerPassword, "Cached password should be updated");
+  [dataArray] = await storageChangedPromised;
+  login = dataArray.queryElementAt(1, Ci.nsILoginInfo);
+  expected.password = newerPassword;
+  Assert.ok(login.equals(expected), "Check updated login");
+  equal(
+    (await Services.logins.getAllLogins()).length,
+    1,
+    "Should have 1 saved login still"
+  );
+
+  checkEditTelemetryRecorded(1, "with auto-save");
+
+  LoginManagerParent._browsingContextGlobal.get.restore();
+  restorePrompter();
+  LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+  Services.logins.removeAllUserFacingLogins();
+  Services.telemetry.clearEvents();
+});
+
+add_task(
+  async function test_onPasswordEditedOrGenerated_editToEmpty_generatedPassword() {
+    await startTestConditions(99);
+    let { generatedPassword } = await stubGeneratedPasswordForBrowsingContextId(
+      99
+    );
+    let { fakePromptToChangePassword, restorePrompter } = stubPrompter();
+    let rootBrowser = LMP.getRootBrowser();
+
+    let storageChangedPromised = TestUtils.topicObserved(
+      "passwordmgr-storage-changed",
+      (_, data) => data == "addLogin"
+    );
+
+    equal(
+      (await Services.logins.getAllLogins()).length,
+      0,
+      "Should have no saved logins at the start of the test"
+    );
+
+    await LMP._onPasswordEditedOrGenerated(
+      rootBrowser,
+      "https://www.example.com",
+      {
+        browsingContextId: 99,
+        formActionOrigin: "https://www.mozilla.org",
+        newPasswordField: { value: generatedPassword },
+        usernameField: { value: "someusername" },
+        triggeredByFillingGenerated: true,
+      }
+    );
+
+    let [login] = await storageChangedPromised;
+    let expected = new LoginInfo(
+      "https://www.example.com",
+      "https://www.mozilla.org",
+      null,
+      "", // verify we don't include the username when auto-saving a login
+      generatedPassword
+    );
+
+    Assert.ok(login.equals(expected), "Check added login");
+    Assert.ok(LMP._getPrompter.calledOnce, "Checking _getPrompter was called");
+    Assert.ok(
+      fakePromptToChangePassword.calledOnce,
+      "Checking promptToChangePassword was called"
+    );
+    Assert.ok(
+      fakePromptToChangePassword.getCall(0).args[3],
+      "promptToChangePassword had a truthy 'dismissed' argument"
+    );
+    Assert.ok(
+      fakePromptToChangePassword.getCall(0).args[4],
+      "promptToChangePassword had a truthy 'notifySaved' argument"
+    );
+
+    info("Edit the password to be empty");
+    const newPassword = "";
+    await LMP._onPasswordEditedOrGenerated(
+      rootBrowser,
+      "https://www.example.com",
+      {
+        browsingContextId: 99,
+        formActionOrigin: "https://www.mozilla.org",
+        newPasswordField: { value: newPassword },
+        usernameField: { value: "someusername" },
+        triggeredByFillingGenerated: true,
+      }
+    );
+    let generatedPW =
+      LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+        "https://www.example.com^userContextId=6"
+      );
+    Assert.ok(!generatedPW.edited, "Cached edited boolean should be false");
+    equal(
+      generatedPW.value,
+      generatedPassword,
+      "Cached password shouldn't be updated"
+    );
+
+    checkEditTelemetryRecorded(0, "Blanking doesn't count as an edit");
+
+    LoginManagerParent._browsingContextGlobal.get.restore();
+    restorePrompter();
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+    Services.logins.removeAllUserFacingLogins();
+    Services.telemetry.clearEvents();
+  }
+);
+
+add_task(async function test_addUsernameBeforeAutoSaveEdit() {
+  await startTestConditions(99);
+  let { generatedPassword } = await stubGeneratedPasswordForBrowsingContextId(
+    99
+  );
+  let { fakePromptToChangePassword, restorePrompter, resetPrompterHistory } =
+    stubPrompter();
+  let rootBrowser = LMP.getRootBrowser();
+  let fakePopupNotifications = {
+    getNotification: sinon.stub().returns({ dismissed: true }),
+  };
+  sinon.stub(LoginHelper, "getBrowserForPrompt").callsFake(() => {
+    return {
+      ownerGlobal: {
+        PopupNotifications: fakePopupNotifications,
+      },
+    };
+  });
+
+  let storageChangedPromised = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    (_, data) => data == "addLogin"
+  );
+
+  equal(
+    (await Services.logins.getAllLogins()).length,
+    0,
+    "Should have no saved logins at the start of the test"
+  );
+
+  await LMP._onPasswordEditedOrGenerated(
+    rootBrowser,
+    "https://www.example.com",
+    {
+      browsingContextId: 99,
+      formActionOrigin: "https://www.mozilla.org",
+      newPasswordField: { value: generatedPassword },
+      usernameField: { value: "someusername" },
+      triggeredByFillingGenerated: true,
+    }
+  );
+
+  let [login] = await storageChangedPromised;
+  let expected = new LoginInfo(
+    "https://www.example.com",
+    "https://www.mozilla.org",
+    null,
+    "", // verify we don't include the username when auto-saving a login
+    generatedPassword
+  );
+
+  Assert.ok(login.equals(expected), "Check added login");
+  Assert.ok(LMP._getPrompter.calledOnce, "Checking _getPrompter was called");
+  Assert.ok(
+    fakePromptToChangePassword.calledOnce,
+    "Checking promptToChangePassword was called"
+  );
+  Assert.ok(
+    fakePromptToChangePassword.getCall(0).args[3],
+    "promptToChangePassword had a truthy 'dismissed' argument"
+  );
+  Assert.ok(
+    fakePromptToChangePassword.getCall(0).args[4],
+    "promptToChangePassword had a truthy 'notifySaved' argument"
+  );
+
+  info("Checking the getNotification stub");
+  Assert.ok(
+    !fakePopupNotifications.getNotification.called,
+    "getNotification didn't get called yet"
+  );
+  resetPrompterHistory();
+
+  info("Add a username to the auto-saved login in storage");
+  let loginWithUsername = login.clone();
+  loginWithUsername.username = "added_username";
+  LoginManagerPrompter._updateLogin(login, loginWithUsername);
+
+  info("Edit the password");
+  const newPassword = generatedPassword + "🔥";
+  storageChangedPromised = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    (_, data) => data == "modifyLogin"
+  );
+  // will update the doorhanger with changed password
+  await LMP._onPasswordEditedOrGenerated(
+    rootBrowser,
+    "https://www.example.com",
+    {
+      browsingContextId: 99,
+      formActionOrigin: "https://www.mozilla.org",
+      newPasswordField: { value: newPassword },
+      usernameField: { value: "someusername" },
+      triggeredByFillingGenerated: true,
+    }
+  );
+  let generatedPW =
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+      "https://www.example.com^userContextId=6"
+    );
+  Assert.ok(generatedPW.edited, "Cached edited boolean should be true");
+  equal(generatedPW.value, newPassword, "Cached password should be updated");
+  let [dataArray] = await storageChangedPromised;
+  login = dataArray.queryElementAt(1, Ci.nsILoginInfo);
+  loginWithUsername.password = newPassword;
+  // the password should be updated in storage, but not the username (until the user confirms the doorhanger)
+  assertLoginProperties(login, loginWithUsername);
+  Assert.ok(login.matches(loginWithUsername, false), "Check updated login");
+  equal(
+    (await Services.logins.getAllLogins()).length,
+    1,
+    "Should have 1 saved login still"
+  );
+
+  Assert.ok(
+    fakePopupNotifications.getNotification.calledOnce,
+    "getNotification was called"
+  );
+  Assert.ok(LMP._getPrompter.calledOnce, "Checking _getPrompter was called");
+  Assert.ok(
+    fakePromptToChangePassword.calledOnce,
+    "Checking promptToChangePassword was called"
+  );
+  Assert.ok(
+    fakePromptToChangePassword.getCall(0).args[3],
+    "promptToChangePassword had a truthy 'dismissed' argument"
+  );
+  // The generated password changed, so we expect notifySaved to be true
+  Assert.ok(
+    fakePromptToChangePassword.getCall(0).args[4],
+    "promptToChangePassword should have a falsey 'notifySaved' argument"
+  );
+  resetPrompterHistory();
+
+  info(
+    "Simulate a second edit to check that the telemetry event for the first edit is not recorded twice"
+  );
+  const newerPassword = newPassword + "🦊";
+  storageChangedPromised = TestUtils.topicObserved(
+    "passwordmgr-storage-changed",
+    (_, data) => data == "modifyLogin"
+  );
+  info("Calling _onPasswordEditedOrGenerated again");
+  await LMP._onPasswordEditedOrGenerated(
+    rootBrowser,
+    "https://www.example.com",
+    {
+      browsingContextId: 99,
+      formActionOrigin: "https://www.mozilla.org",
+      newPasswordField: { value: newerPassword },
+      usernameField: { value: "someusername" },
+      triggeredByFillingGenerated: true,
+    }
+  );
+  generatedPW = LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+    "https://www.example.com^userContextId=6"
+  );
+  Assert.ok(generatedPW.edited, "Cached edited state should remain true");
+  equal(generatedPW.value, newerPassword, "Cached password should be updated");
+  [dataArray] = await storageChangedPromised;
+  login = dataArray.queryElementAt(1, Ci.nsILoginInfo);
+  loginWithUsername.password = newerPassword;
+  assertLoginProperties(login, loginWithUsername);
+  Assert.ok(login.matches(loginWithUsername, false), "Check updated login");
+  equal(
+    (await Services.logins.getAllLogins()).length,
+    1,
+    "Should have 1 saved login still"
+  );
+
+  checkEditTelemetryRecorded(1, "with auto-save");
+
+  Assert.ok(
+    fakePromptToChangePassword.calledOnce,
+    "Checking promptToChangePassword was called"
+  );
+  equal(
+    fakePromptToChangePassword.getCall(0).args[2].password,
+    newerPassword,
+    "promptToChangePassword had the updated password"
+  );
+  Assert.ok(
+    fakePromptToChangePassword.getCall(0).args[3],
+    "promptToChangePassword had a truthy 'dismissed' argument"
+  );
+
+  LoginManagerParent._browsingContextGlobal.get.restore();
+  LoginHelper.getBrowserForPrompt.restore();
+  restorePrompter();
+  LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+  Services.logins.removeAllUserFacingLogins();
+  Services.telemetry.clearEvents();
+});
+
+add_task(async function test_editUsernameOfFilledSavedLogin() {
+  await startTestConditions(99);
+  await stubGeneratedPasswordForBrowsingContextId(99);
+  let {
+    fakePromptToChangePassword,
+    fakePromptToSavePassword,
+    restorePrompter,
+    resetPrompterHistory,
+  } = stubPrompter();
+  let rootBrowser = LMP.getRootBrowser();
+  let fakePopupNotifications = {
+    getNotification: sinon.stub().returns({ dismissed: true }),
+  };
+  sinon.stub(LoginHelper, "getBrowserForPrompt").callsFake(() => {
+    return {
+      ownerGlobal: {
+        PopupNotifications: fakePopupNotifications,
+      },
+    };
+  });
+
+  let login0Props = Object.assign({}, loginTemplate, {
+    username: "someusername",
+    password: "qweqweq",
+  });
+  info("Adding initial login: " + JSON.stringify(login0Props));
+  let savedLogin = await LoginTestUtils.addLogin(login0Props);
+
+  let logins = await Services.logins.getAllLogins();
+  info("Saved initial login: " + JSON.stringify(logins[0]));
+
+  equal(logins.length, 1, "Should have 1 saved login at the start of the test");
+
+  // first prompt to save a new login
+  let newUsername = "differentuser";
+  let newPassword = login0Props.password + "🔥";
+  await LMP._onPasswordEditedOrGenerated(
+    rootBrowser,
+    "https://www.example.com",
+    {
+      browsingContextId: 99,
+      formActionOrigin: "https://www.mozilla.org",
+      autoFilledLoginGuid: savedLogin.guid,
+      newPasswordField: { value: newPassword },
+      usernameField: { value: newUsername },
+      triggeredByFillingGenerated: false,
+    }
+  );
+
+  let expected = new LoginInfo(
+    login0Props.origin,
+    login0Props.formActionOrigin,
+    null,
+    newUsername,
+    newPassword
+  );
+
+  Assert.ok(LMP._getPrompter.calledOnce, "Checking _getPrompter was called");
+  info("Checking the getNotification stub");
+  Assert.ok(
+    !fakePopupNotifications.getNotification.called,
+    "getNotification was not called"
+  );
+  Assert.ok(
+    fakePromptToSavePassword.calledOnce,
+    "Checking promptToSavePassword was called"
+  );
+  Assert.ok(
+    fakePromptToSavePassword.getCall(0).args[2],
+    "promptToSavePassword had a truthy 'dismissed' argument"
+  );
+  Assert.ok(
+    !fakePromptToSavePassword.getCall(0).args[3],
+    "promptToSavePassword had a falsey 'notifySaved' argument"
+  );
+  assertLoginProperties(fakePromptToSavePassword.getCall(0).args[1], expected);
+  resetPrompterHistory();
+
+  // then prompt with matching username/password
+  await LMP._onPasswordEditedOrGenerated(
+    rootBrowser,
+    "https://www.example.com",
+    {
+      browsingContextId: 99,
+      formActionOrigin: "https://www.mozilla.org",
+      autoFilledLoginGuid: savedLogin.guid,
+      newPasswordField: { value: login0Props.password },
+      usernameField: { value: login0Props.username },
+      triggeredByFillingGenerated: false,
+    }
+  );
+
+  expected = new LoginInfo(
+    login0Props.origin,
+    login0Props.formActionOrigin,
+    null,
+    login0Props.username,
+    login0Props.password
+  );
+
+  Assert.ok(LMP._getPrompter.calledOnce, "Checking _getPrompter was called");
+  info("Checking the getNotification stub");
+  Assert.ok(
+    fakePopupNotifications.getNotification.called,
+    "getNotification was called"
+  );
+  Assert.ok(
+    fakePromptToChangePassword.calledOnce,
+    "Checking promptToChangePassword was called"
+  );
+  Assert.ok(
+    fakePromptToChangePassword.getCall(0).args[3],
+    "promptToChangePassword had a truthy 'dismissed' argument"
+  );
+  Assert.ok(
+    !fakePromptToChangePassword.getCall(0).args[4],
+    "promptToChangePassword had a falsey 'notifySaved' argument"
+  );
+  assertLoginProperties(
+    fakePromptToChangePassword.getCall(0).args[2],
+    expected
+  );
+  resetPrompterHistory();
+
+  LoginManagerParent._browsingContextGlobal.get.restore();
+  LoginHelper.getBrowserForPrompt.restore();
+  restorePrompter();
+  LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+  Services.logins.removeAllUserFacingLogins();
+  Services.telemetry.clearEvents();
+});
+
+add_task(
+  async function test_onPasswordEditedOrGenerated_generatedPassword_withDisabledLogin() {
+    await startTestConditions(99);
+    let { generatedPassword } = await stubGeneratedPasswordForBrowsingContextId(
+      99
+    );
+    let { restorePrompter } = stubPrompter();
+    let rootBrowser = LMP.getRootBrowser();
+
+    info("Disable login saving for the site");
+    Services.logins.setLoginSavingEnabled("https://www.example.com", false);
+    await LMP._onPasswordEditedOrGenerated(
+      rootBrowser,
+      "https://www.example.com",
+      {
+        browsingContextId: 99,
+        formActionOrigin: "https://www.mozilla.org",
+        newPasswordField: { value: generatedPassword },
+        triggeredByFillingGenerated: true,
+      }
+    );
+    equal(
+      (await Services.logins.getAllLogins()).length,
+      0,
+      "Should have no saved logins since saving is disabled"
+    );
+    Assert.ok(
+      LMP._getPrompter.notCalled,
+      "Checking _getPrompter wasn't called"
+    );
+
+    // Clean up
+    LoginManagerParent._browsingContextGlobal.get.restore();
+    restorePrompter();
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+    Services.logins.setLoginSavingEnabled("https://www.example.com", true);
+    Services.logins.removeAllUserFacingLogins();
+  }
+);
+
+add_task(
+  async function test_onPasswordEditedOrGenerated_generatedPassword_withSavedEmptyUsername() {
+    await startTestConditions(99);
+    let login0Props = Object.assign({}, loginTemplate, {
+      username: "",
+      password: "qweqweq",
+    });
+    info("Adding initial login: " + JSON.stringify(login0Props));
+    let expected = await LoginTestUtils.addLogin(login0Props);
+
+    info(
+      "Saved initial login: " +
+        JSON.stringify(Services.logins.getAllLogins()[0])
+    );
+
+    let { generatedPassword: password1 } =
+      await stubGeneratedPasswordForBrowsingContextId(99);
+    let { restorePrompter, fakePromptToChangePassword } = stubPrompter();
+    let rootBrowser = LMP.getRootBrowser();
+
+    await LMP._onPasswordEditedOrGenerated(
+      rootBrowser,
+      "https://www.example.com",
+      {
+        browsingContextId: 99,
+        formActionOrigin: "https://www.mozilla.org",
+        newPasswordField: { value: password1 },
+        triggeredByFillingGenerated: true,
+      }
+    );
+    let logins = await Services.logins.getAllLogins();
+    equal(
+      logins.length,
+      1,
+      "Should just have the previously-saved login with empty username"
+    );
+    assertLoginProperties(logins[0], login0Props);
+
+    Assert.ok(LMP._getPrompter.calledOnce, "Checking _getPrompter was called");
+    Assert.ok(
+      fakePromptToChangePassword.calledOnce,
+      "Checking promptToChangePassword was called"
+    );
+    Assert.ok(
+      fakePromptToChangePassword.getCall(0).args[3],
+      "promptToChangePassword had a truthy 'dismissed' argument"
+    );
+    Assert.ok(
+      !fakePromptToChangePassword.getCall(0).args[4],
+      "promptToChangePassword had a falsey 'notifySaved' argument"
+    );
+
+    info("Edit the password");
+    const newPassword = password1 + "🔥";
+    await LMP._onPasswordEditedOrGenerated(
+      rootBrowser,
+      "https://www.example.com",
+      {
+        browsingContextId: 99,
+        formActionOrigin: "https://www.mozilla.org",
+        newPasswordField: { value: newPassword },
+        usernameField: { value: "someusername" },
+        triggeredByFillingGenerated: true,
+      }
+    );
+    let generatedPW =
+      LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+        "https://www.example.com^userContextId=6"
+      );
+    Assert.ok(generatedPW.edited, "Cached edited boolean should be true");
+    equal(generatedPW.storageGUID, null, "Should have no storageGUID");
+    equal(generatedPW.value, newPassword, "Cached password should be updated");
+    logins = await Services.logins.getAllLogins();
+    assertLoginProperties(logins[0], login0Props);
+    Assert.ok(logins[0].equals(expected), "Ensure no changes");
+    equal(logins.length, 1, "Should have 1 saved login still");
+
+    checkEditTelemetryRecorded(1, "Updating cache, not storage (no auto-save)");
+
+    LoginManagerParent._browsingContextGlobal.get.restore();
+    restorePrompter();
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+    Services.logins.removeAllUserFacingLogins();
+    Services.telemetry.clearEvents();
+  }
+);
+
+add_task(
+  async function test_onPasswordEditedOrGenerated_generatedPassword_withSavedEmptyUsernameAndUsernameValue() {
+    // Save as the above task but with a non-empty username field value.
+    await startTestConditions(99);
+    let login0Props = Object.assign({}, loginTemplate, {
+      username: "",
+      password: "qweqweq",
+    });
+    info("Adding initial login: " + JSON.stringify(login0Props));
+    let expected = await LoginTestUtils.addLogin(login0Props);
+
+    info(
+      "Saved initial login: " +
+        JSON.stringify(await Services.logins.getAllLogins()[0])
+    );
+
+    let { generatedPassword: password1 } =
+      await stubGeneratedPasswordForBrowsingContextId(99);
+    let {
+      restorePrompter,
+      fakePromptToChangePassword,
+      fakePromptToSavePassword,
+    } = stubPrompter();
+    let rootBrowser = LMP.getRootBrowser();
+
+    await LMP._onPasswordEditedOrGenerated(
+      rootBrowser,
+      "https://www.example.com",
+      {
+        browsingContextId: 99,
+        formActionOrigin: "https://www.mozilla.org",
+        newPasswordField: { value: password1 },
+        usernameField: { value: "non-empty-username" },
+        triggeredByFillingGenerated: true,
+      }
+    );
+    let logins = await Services.logins.getAllLogins();
+    equal(
+      logins.length,
+      1,
+      "Should just have the previously-saved login with empty username"
+    );
+    assertLoginProperties(logins[0], login0Props);
+
+    Assert.ok(LMP._getPrompter.calledOnce, "Checking _getPrompter was called");
+    Assert.ok(
+      fakePromptToChangePassword.notCalled,
+      "Checking promptToChangePassword wasn't called"
+    );
+    Assert.ok(
+      fakePromptToSavePassword.calledOnce,
+      "Checking promptToSavePassword was called"
+    );
+    Assert.ok(
+      fakePromptToSavePassword.getCall(0).args[2],
+      "promptToSavePassword had a truthy 'dismissed' argument"
+    );
+    Assert.ok(
+      !fakePromptToSavePassword.getCall(0).args[3],
+      "promptToSavePassword had a falsey 'notifySaved' argument"
+    );
+
+    info("Edit the password");
+    const newPassword = password1 + "🔥";
+    await LMP._onPasswordEditedOrGenerated(
+      rootBrowser,
+      "https://www.example.com",
+      {
+        browsingContextId: 99,
+        formActionOrigin: "https://www.mozilla.org",
+        newPasswordField: { value: newPassword },
+        usernameField: { value: "non-empty-username" },
+        triggeredByFillingGenerated: true,
+      }
+    );
+    Assert.ok(
+      fakePromptToChangePassword.notCalled,
+      "Checking promptToChangePassword wasn't called"
+    );
+    Assert.ok(
+      fakePromptToSavePassword.calledTwice,
+      "Checking promptToSavePassword was called again"
+    );
+    Assert.ok(
+      fakePromptToSavePassword.getCall(1).args[2],
+      "promptToSavePassword had a truthy 'dismissed' argument"
+    );
+    Assert.ok(
+      !fakePromptToSavePassword.getCall(1).args[3],
+      "promptToSavePassword had a falsey 'notifySaved' argument"
+    );
+
+    let generatedPW =
+      LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().get(
+        "https://www.example.com^userContextId=6"
+      );
+    Assert.ok(generatedPW.edited, "Cached edited boolean should be true");
+    equal(generatedPW.storageGUID, null, "Should have no storageGUID");
+    equal(generatedPW.value, newPassword, "Cached password should be updated");
+    logins = await Services.logins.getAllLogins();
+    assertLoginProperties(logins[0], login0Props);
+    Assert.ok(logins[0].equals(expected), "Ensure no changes");
+    equal(logins.length, 1, "Should have 1 saved login still");
+
+    checkEditTelemetryRecorded(
+      1,
+      "Updating cache, not storage (no auto-save) with username in field"
+    );
+
+    LoginManagerParent._browsingContextGlobal.get.restore();
+    restorePrompter();
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+    Services.logins.removeAllUserFacingLogins();
+    Services.telemetry.clearEvents();
+  }
+);
+
+add_task(
+  async function test_onPasswordEditedOrGenerated_generatedPassword_withEmptyUsernameDifferentFormActionOrigin() {
+    await startTestConditions(99);
+    let login0Props = Object.assign({}, loginTemplate, {
+      username: "",
+      password: "qweqweq",
+    });
+    await LoginTestUtils.addLogin(login0Props);
+
+    let { generatedPassword: password1 } =
+      await stubGeneratedPasswordForBrowsingContextId(99);
+    let { restorePrompter, fakePromptToChangePassword } = stubPrompter();
+    let rootBrowser = LMP.getRootBrowser();
+
+    await LMP._onPasswordEditedOrGenerated(
+      rootBrowser,
+      "https://www.example.com",
+      {
+        browsingContextId: 99,
+        formActionOrigin: "https://www.elsewhere.com",
+        newPasswordField: { value: password1 },
+        triggeredByFillingGenerated: true,
+      }
+    );
+
+    let savedLogins = await Services.logins.getAllLogins();
+    equal(
+      savedLogins.length,
+      2,
+      "Should have saved the generated-password login"
+    );
+
+    assertLoginProperties(savedLogins[0], login0Props);
+    assertLoginProperties(
+      savedLogins[1],
+      Object.assign({}, loginTemplate, {
+        formActionOrigin: "https://www.elsewhere.com",
+        username: "",
+        password: password1,
+      })
+    );
+
+    Assert.ok(LMP._getPrompter.calledOnce, "Checking _getPrompter was called");
+    Assert.ok(
+      fakePromptToChangePassword.calledOnce,
+      "Checking promptToChangePassword was called"
+    );
+    Assert.ok(
+      fakePromptToChangePassword.getCall(0).args[2],
+      "promptToChangePassword had a truthy 'dismissed' argument"
+    );
+    Assert.ok(
+      fakePromptToChangePassword.getCall(0).args[3],
+      "promptToChangePassword had a truthy 'notifySaved' argument"
+    );
+
+    LoginManagerParent._browsingContextGlobal.get.restore();
+    restorePrompter();
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+    Services.logins.removeAllUserFacingLogins();
+  }
+);
+
+add_task(
+  async function test_onPasswordEditedOrGenerated_generatedPassword_withSavedUsername() {
+    await startTestConditions(99);
+    let login0Props = Object.assign({}, loginTemplate, {
+      username: "previoususer",
+      password: "qweqweq",
+    });
+    await LoginTestUtils.addLogin(login0Props);
+
+    let { generatedPassword: password1 } =
+      await stubGeneratedPasswordForBrowsingContextId(99);
+    let { restorePrompter, fakePromptToChangePassword } = stubPrompter();
+    let rootBrowser = LMP.getRootBrowser();
+
+    await LMP._onPasswordEditedOrGenerated(
+      rootBrowser,
+      "https://www.example.com",
+      {
+        browsingContextId: 99,
+        formActionOrigin: "https://www.mozilla.org",
+        newPasswordField: { value: password1 },
+        triggeredByFillingGenerated: true,
+      }
+    );
+
+    let savedLogins = await Services.logins.getAllLogins();
+    equal(
+      savedLogins.length,
+      2,
+      "Should have saved the generated-password login"
+    );
+    assertLoginProperties(savedLogins[0], login0Props);
+    assertLoginProperties(
+      savedLogins[1],
+      Object.assign({}, loginTemplate, {
+        username: "",
+        password: password1,
+      })
+    );
+
+    Assert.ok(LMP._getPrompter.calledOnce, "Checking _getPrompter was called");
+    Assert.ok(
+      fakePromptToChangePassword.calledOnce,
+      "Checking promptToChangePassword was called"
+    );
+    Assert.ok(
+      fakePromptToChangePassword.getCall(0).args[2],
+      "promptToChangePassword had a truthy 'dismissed' argument"
+    );
+    Assert.ok(
+      fakePromptToChangePassword.getCall(0).args[3],
+      "promptToChangePassword had a truthy 'notifySaved' argument"
+    );
+
+    LoginManagerParent._browsingContextGlobal.get.restore();
+    restorePrompter();
+    LoginManagerParent.getGeneratedPasswordsByPrincipalOrigin().clear();
+    Services.logins.removeAllUserFacingLogins();
+  }
+);
diff --git a/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_searchAndDedupeLogins.js b/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_searchAndDedupeLogins.js
new file mode 100644
index 0000000000..33ee5bd04c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_LoginManagerParent_searchAndDedupeLogins.js
@@ -0,0 +1,207 @@
+/**
+ * Test LoginManagerParent._searchAndDedupeLogins()
+ */
+
+"use strict";
+
+const { LoginManagerParent: LMP } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerParent.sys.mjs"
+);
+
+const DOMAIN1_HTTP_ORIGIN = "http://www3.example.com";
+const DOMAIN1_HTTPS_ORIGIN = "https://www3.example.com";
+
+const DOMAIN1_HTTP_TO_HTTP_U1_P1 = TestData.formLogin({});
+const DOMAIN1_HTTP_TO_HTTP_U2_P1 = TestData.formLogin({
+  username: "user2",
+});
+const DOMAIN1_HTTP_TO_HTTP_U3_P1 = TestData.formLogin({
+  username: "user3",
+});
+const DOMAIN1_HTTPS_TO_HTTPS_U1_P1 = TestData.formLogin({
+  origin: DOMAIN1_HTTPS_ORIGIN,
+  formActionOrigin: "https://login.example.com",
+});
+const DOMAIN1_HTTPS_TO_HTTPS_U2_P1 = TestData.formLogin({
+  origin: DOMAIN1_HTTPS_ORIGIN,
+  formActionOrigin: "https://login.example.com",
+  username: "user2",
+});
+const DOMAIN1_HTTPS_TO_HTTPS_U1_P2 = TestData.formLogin({
+  origin: DOMAIN1_HTTPS_ORIGIN,
+  formActionOrigin: "https://login.example.com",
+  password: "password two",
+});
+const DOMAIN1_HTTPS_TO_HTTPS_U1_P2_DIFFERENT_PORT = TestData.formLogin({
+  origin: "https://www3.example.com:8080",
+  password: "password two",
+});
+const DOMAIN1_HTTP_TO_HTTP_U1_P2 = TestData.formLogin({
+  password: "password two",
+});
+const DOMAIN1_HTTP_TO_HTTP_U1_P1_DIFFERENT_PORT = TestData.formLogin({
+  origin: "http://www3.example.com:8080",
+});
+const DOMAIN2_HTTP_TO_HTTP_U1_P1 = TestData.formLogin({
+  origin: "http://different.example.com",
+});
+const DOMAIN2_HTTPS_TO_HTTPS_U1_P1 = TestData.formLogin({
+  origin: "https://different.example.com",
+  formActionOrigin: "https://login.example.com",
+});
+
+add_task(function setup() {
+  // Not enabled by default in all.js:
+  Services.prefs.setBoolPref("signon.schemeUpgrades", true);
+});
+
+add_task(async function test_searchAndDedupeLogins_acceptDifferentSubdomains() {
+  let testcases = [
+    {
+      description: "HTTPS form, same hostPort, same username, different scheme",
+      formActionOrigin: DOMAIN1_HTTPS_ORIGIN,
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      expected: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1],
+    },
+    {
+      description: "HTTP form, same hostPort, same username, different scheme",
+      formActionOrigin: DOMAIN1_HTTP_ORIGIN,
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      expected: [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+    },
+    {
+      description: "HTTPS form, different passwords, different scheme",
+      formActionOrigin: DOMAIN1_HTTPS_ORIGIN,
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P2],
+      expected: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1],
+    },
+    {
+      description: "HTTP form, different passwords, different scheme",
+      formActionOrigin: DOMAIN1_HTTP_ORIGIN,
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P2],
+      expected: [DOMAIN1_HTTP_TO_HTTP_U1_P2],
+    },
+    {
+      description: "HTTPS form, same origin, different port, both schemes",
+      formActionOrigin: DOMAIN1_HTTPS_ORIGIN,
+      logins: [
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P1,
+        DOMAIN1_HTTP_TO_HTTP_U1_P1_DIFFERENT_PORT,
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P2_DIFFERENT_PORT,
+      ],
+      expected: [
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P1,
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P2_DIFFERENT_PORT,
+      ],
+    },
+    {
+      description: "HTTP form, same origin, different port, both schemes",
+      formActionOrigin: DOMAIN1_HTTP_ORIGIN,
+      logins: [
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P1,
+        DOMAIN1_HTTP_TO_HTTP_U1_P1_DIFFERENT_PORT,
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P2_DIFFERENT_PORT,
+      ],
+      expected: [DOMAIN1_HTTP_TO_HTTP_U1_P1_DIFFERENT_PORT],
+    },
+    {
+      description: "HTTPS form, different origin, different scheme",
+      formActionOrigin: DOMAIN1_HTTPS_ORIGIN,
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN2_HTTP_TO_HTTP_U1_P1],
+      expected: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1],
+    },
+    {
+      description:
+        "HTTPS form, different origin, different scheme, same password, same hostPort preferred",
+      formActionOrigin: DOMAIN1_HTTPS_ORIGIN,
+      logins: [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN2_HTTPS_TO_HTTPS_U1_P1],
+      expected: [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+    },
+    {
+      description: "HTTP form, different origin, different scheme",
+      formActionOrigin: DOMAIN1_HTTP_ORIGIN,
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN2_HTTP_TO_HTTP_U1_P1],
+      expected: [DOMAIN2_HTTP_TO_HTTP_U1_P1],
+    },
+    {
+      description: "HTTPS form, different username, different scheme",
+      formActionOrigin: DOMAIN1_HTTPS_ORIGIN,
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U2_P1],
+      expected: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U2_P1],
+    },
+    {
+      description: "HTTP form, different username, different scheme",
+      formActionOrigin: DOMAIN1_HTTP_ORIGIN,
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U2_P1],
+      expected: [DOMAIN1_HTTP_TO_HTTP_U2_P1],
+    },
+    {
+      description: "HTTPS form, different usernames, different schemes",
+      formActionOrigin: DOMAIN1_HTTPS_ORIGIN,
+      logins: [
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P2,
+        DOMAIN1_HTTPS_TO_HTTPS_U2_P1,
+        DOMAIN1_HTTP_TO_HTTP_U1_P1,
+        DOMAIN1_HTTP_TO_HTTP_U3_P1,
+      ],
+      expected: [
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P2,
+        DOMAIN1_HTTPS_TO_HTTPS_U2_P1,
+        DOMAIN1_HTTP_TO_HTTP_U3_P1,
+      ],
+    },
+  ];
+
+  for (let tc of testcases) {
+    info(tc.description);
+
+    let guids = await Services.logins.addLogins(tc.logins);
+    Assert.strictEqual(
+      guids.length,
+      tc.logins.length,
+      "Check length of added logins"
+    );
+
+    let actual = await LMP.searchAndDedupeLogins(tc.formActionOrigin, {
+      formActionOrigin: tc.formActionOrigin,
+      looseActionOriginMatch: true,
+      acceptDifferentSubdomains: true,
+    });
+    info(`actual:\n ${JSON.stringify(actual, null, 2)}`);
+    info(`expected:\n ${JSON.stringify(tc.expected, null, 2)}`);
+    Assert.strictEqual(
+      actual.length,
+      tc.expected.length,
+      `Check result length`
+    );
+    for (let [i, login] of tc.expected.entries()) {
+      Assert.ok(actual[i].equals(login), `Check index ${i}`);
+    }
+
+    Services.logins.removeAllUserFacingLogins();
+  }
+});
+
+add_task(async function test_reject_duplicates() {
+  const testcases = [
+    {
+      description: "HTTPS form, both https, same username, different password",
+      formActionOrigin: DOMAIN1_HTTPS_ORIGIN,
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTPS_TO_HTTPS_U1_P2],
+    },
+    {
+      description: "HTTP form, both https, same username, different password",
+      formActionOrigin: DOMAIN1_HTTP_ORIGIN,
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTPS_TO_HTTPS_U1_P2],
+    },
+  ];
+
+  for (const tc of testcases) {
+    info(tc.description);
+
+    const result = await Services.logins.addLogins(tc.logins);
+    Assert.equal(result.length, 1, "only single login added");
+
+    Services.logins.removeAllUserFacingLogins();
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_LoginManagerPrompter_getUsernameSuggestions.js b/toolkit/components/passwordmgr/test/unit/test_LoginManagerPrompter_getUsernameSuggestions.js
new file mode 100644
index 0000000000..d3a94ba08b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_LoginManagerPrompter_getUsernameSuggestions.js
@@ -0,0 +1,188 @@
+const { LoginManagerPrompter } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerPrompter.sys.mjs"
+);
+
+const TEST_CASES = [
+  {
+    description: "page values should appear before saved values",
+    savedLogins: [{ username: "savedUsername", password: "savedPassword" }],
+    possibleUsernames: ["pageUsername"],
+    expectedSuggestions: [
+      { text: "pageUsername", style: "possible-username" },
+      { text: "savedUsername", style: "login" },
+    ],
+    isLoggedIn: true,
+  },
+  {
+    description: "duplicate page values should be deduped",
+    savedLogins: [],
+    possibleUsernames: ["pageUsername", "pageUsername", "pageUsername2"],
+    expectedSuggestions: [
+      { text: "pageUsername", style: "possible-username" },
+      { text: "pageUsername2", style: "possible-username" },
+    ],
+    isLoggedIn: true,
+  },
+  {
+    description: "page values should dedupe and win over saved values",
+    savedLogins: [{ username: "username", password: "savedPassword" }],
+    possibleUsernames: ["username"],
+    expectedSuggestions: [{ text: "username", style: "possible-username" }],
+    isLoggedIn: true,
+  },
+  {
+    description: "empty usernames should be filtered out",
+    savedLogins: [{ username: "", password: "savedPassword" }],
+    possibleUsernames: [""],
+    expectedSuggestions: [],
+    isLoggedIn: true,
+  },
+  {
+    description: "auth logins should be displayed alongside normal ones",
+    savedLogins: [
+      { username: "normalUsername", password: "normalPassword" },
+      { isAuth: true, username: "authUsername", password: "authPassword" },
+    ],
+    possibleUsernames: [""],
+    expectedSuggestions: [
+      { text: "normalUsername", style: "login" },
+      { text: "authUsername", style: "login" },
+    ],
+    isLoggedIn: true,
+  },
+  {
+    description: "saved logins from subdomains should be displayed",
+    savedLogins: [
+      {
+        username: "savedUsername",
+        password: "savedPassword",
+        origin: "https://subdomain.example.com",
+      },
+    ],
+    possibleUsernames: [],
+    expectedSuggestions: [{ text: "savedUsername", style: "login" }],
+    isLoggedIn: true,
+  },
+  {
+    description: "usernames from different subdomains should be deduped",
+    savedLogins: [
+      {
+        username: "savedUsername",
+        password: "savedPassword",
+        origin: "https://subdomain.example.com",
+      },
+      {
+        username: "savedUsername",
+        password: "savedPassword",
+        origin: "https://example.com",
+      },
+    ],
+    possibleUsernames: [],
+    expectedSuggestions: [{ text: "savedUsername", style: "login" }],
+    isLoggedIn: true,
+  },
+  {
+    description: "No results with saved login when Primary Password is locked",
+    savedLogins: [
+      {
+        username: "savedUsername",
+        password: "savedPassword",
+        origin: "https://example.com",
+      },
+    ],
+    possibleUsernames: [],
+    expectedSuggestions: [],
+    isLoggedIn: false,
+  },
+];
+
+const LOGIN = TestData.formLogin({
+  origin: "https://example.com",
+  formActionOrigin: "https://example.com",
+  username: "LOGIN is used only for its origin",
+  password: "LOGIN is used only for its origin",
+});
+
+function _setPrefs() {
+  Services.prefs.setBoolPref("signon.capture.inputChanges.enabled", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.capture.inputChanges.enabled");
+  });
+}
+
+async function _saveLogins(loginDatas) {
+  const logins = loginDatas.map(loginData => {
+    let login;
+    if (loginData.isAuth) {
+      login = TestData.authLogin({
+        origin: loginData.origin ?? "https://example.com",
+        httpRealm: "example-realm",
+        username: loginData.username,
+        password: loginData.password,
+      });
+    } else {
+      login = TestData.formLogin({
+        origin: loginData.origin ?? "https://example.com",
+        formActionOrigin: "https://example.com",
+        username: loginData.username,
+        password: loginData.password,
+      });
+    }
+    return login;
+  });
+  await Services.logins.addLogins(logins);
+}
+
+function _compare(expectedArr, actualArr) {
+  Assert.ok(!!expectedArr, "Expect expectedArr to be truthy");
+  Assert.ok(!!actualArr, "Expect actualArr to be truthy");
+  Assert.ok(
+    expectedArr.length == actualArr.length,
+    "Expect expectedArr and actualArr to be the same length"
+  );
+  for (let i = 0; i < expectedArr.length; i++) {
+    const expected = expectedArr[i];
+    const actual = actualArr[i];
+
+    Assert.ok(
+      expected.text == actual.text,
+      `Expect element #${i} text to match.  Expected: '${expected.text}', Actual '${actual.text}'`
+    );
+    Assert.ok(
+      expected.style == actual.style,
+      `Expect element #${i} text to match.  Expected: '${expected.style}', Actual '${actual.style}'`
+    );
+  }
+}
+
+async function _test(testCase) {
+  info(`Starting test case: ${testCase.description}`);
+  info(`Storing saved logins: ${JSON.stringify(testCase.savedLogins)}`);
+  await _saveLogins(testCase.savedLogins);
+
+  if (!testCase.isLoggedIn) {
+    // Primary Password should be enabled and locked
+    LoginTestUtils.primaryPassword.enable();
+  }
+
+  info("Computing results");
+  const result = await LoginManagerPrompter._getUsernameSuggestions(
+    LOGIN,
+    testCase.possibleUsernames
+  );
+
+  _compare(testCase.expectedSuggestions, result);
+
+  info("Cleaning up state");
+  if (!testCase.isLoggedIn) {
+    LoginTestUtils.primaryPassword.disable();
+  }
+  LoginTestUtils.clearData();
+}
+
+add_task(async function test_LoginManagerPrompter_getUsernameSuggestions() {
+  _setPrefs();
+  for (const tc of TEST_CASES) {
+    await _test(tc);
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_OSCrypto_win.js b/toolkit/components/passwordmgr/test/unit/test_OSCrypto_win.js
new file mode 100644
index 0000000000..9545f5ea02
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_OSCrypto_win.js
@@ -0,0 +1,138 @@
+/**
+ * Tests the OSCrypto object.
+ */
+
+"use strict";
+
+// Globals
+
+ChromeUtils.defineESModuleGetters(this, {
+  OSCrypto: "resource://gre/modules/OSCrypto_win.sys.mjs",
+});
+
+let crypto = new OSCrypto();
+
+// Tests
+
+add_task(function test_getIELoginHash() {
+  Assert.equal(
+    crypto.getIELoginHash("https://bugzilla.mozilla.org/page.cgi"),
+    "4A66FE96607885790F8E67B56EEE52AB539BAFB47D"
+  );
+
+  Assert.equal(
+    crypto.getIELoginHash("https://github.com/login"),
+    "0112F7DCE67B8579EA01367678AA44AB9868B5A143"
+  );
+
+  Assert.equal(
+    crypto.getIELoginHash("https://login.live.com/login.srf"),
+    "FBF92E5D804C82717A57856533B779676D92903688"
+  );
+
+  Assert.equal(
+    crypto.getIELoginHash("https://preview.c9.io/riadh/w1/pass.1.html"),
+    "6935CF27628830605927F86AB53831016FC8973D1A"
+  );
+
+  Assert.equal(
+    crypto.getIELoginHash("https://reviewboard.mozilla.org/account/login/"),
+    "09141FD287E2E59A8B1D3BB5671537FD3D6B61337A"
+  );
+
+  Assert.equal(
+    crypto.getIELoginHash("https://www.facebook.com/"),
+    "EF44D3E034009CB0FD1B1D81A1FF3F3335213BD796"
+  );
+});
+
+add_task(function test_decryptData_encryptData() {
+  function encryptDecrypt(value, key) {
+    Assert.ok(true, `Testing value='${value}' with key='${key}'`);
+    let encrypted = crypto.encryptData(value, key);
+    Assert.ok(!!encrypted, "Encrypted value returned");
+    let decrypted = crypto.decryptData(encrypted, key);
+    Assert.equal(decrypted, value, "Decrypted value matches initial value");
+    return decrypted;
+  }
+
+  let values = [
+    "",
+    "secret",
+    "https://www.mozilla.org",
+    "https://reviewboard.mozilla.org",
+    "https://bugzilla.mozilla.org/page.cgi",
+    "新年快樂新年快樂",
+  ];
+  let keys = [
+    null,
+    "a",
+    "keys",
+    "abcdedf",
+    "pass",
+    "https://bugzilla.mozilla.org/page.cgi",
+    "https://login.live.com/login.srf",
+  ];
+  for (let value of values) {
+    for (let key of keys) {
+      Assert.equal(
+        encryptDecrypt(value, key),
+        value,
+        `'${value}' encrypted then decrypted with entropy of '${key}' should match original value.`
+      );
+    }
+  }
+
+  let url = "https://twitter.com/";
+  let value = [
+    1, 0, 0, 0, 208, 140, 157, 223, 1, 21, 209, 17, 140, 122, 0, 192, 79, 194,
+    151, 235, 1, 0, 0, 0, 254, 58, 230, 75, 132, 228, 181, 79, 184, 160, 37,
+    106, 201, 29, 42, 152, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 16, 102, 0, 0, 0, 1, 0,
+    0, 32, 0, 0, 0, 90, 136, 17, 124, 122, 57, 178, 24, 34, 86, 209, 198, 184,
+    107, 58, 58, 32, 98, 61, 239, 129, 101, 56, 239, 114, 159, 139, 165, 183,
+    40, 183, 85, 0, 0, 0, 0, 14, 128, 0, 0, 0, 2, 0, 0, 32, 0, 0, 0, 147, 170,
+    34, 21, 53, 227, 191, 6, 201, 84, 106, 31, 57, 227, 46, 127, 219, 199, 80,
+    142, 37, 104, 112, 223, 26, 165, 223, 55, 176, 89, 55, 37, 112, 0, 0, 0, 98,
+    70, 221, 109, 5, 152, 46, 11, 190, 213, 226, 58, 244, 20, 180, 217, 63, 155,
+    227, 132, 7, 151, 235, 6, 37, 232, 176, 182, 141, 191, 251, 50, 20, 123, 53,
+    11, 247, 233, 112, 121, 130, 27, 168, 68, 92, 144, 192, 7, 12, 239, 53, 217,
+    253, 155, 54, 109, 236, 216, 225, 245, 79, 234, 165, 225, 104, 36, 77, 13,
+    195, 237, 143, 165, 100, 107, 230, 70, 54, 19, 179, 35, 8, 101, 93, 202,
+    121, 210, 222, 28, 93, 122, 36, 84, 185, 249, 238, 3, 102, 149, 248, 94,
+    137, 16, 192, 22, 251, 220, 22, 223, 16, 58, 104, 187, 64, 0, 0, 0, 70, 72,
+    15, 119, 144, 66, 117, 203, 190, 82, 131, 46, 111, 130, 238, 191, 170, 63,
+    186, 117, 46, 88, 171, 3, 94, 146, 75, 86, 243, 159, 63, 195, 149, 25, 105,
+    141, 42, 217, 108, 18, 63, 62, 98, 182, 241, 195, 12, 216, 152, 230, 176,
+    253, 202, 129, 41, 185, 135, 111, 226, 92, 27, 78, 27, 198,
+  ];
+
+  let arr1 = crypto.arrayToString(value);
+  let arr2 = crypto.stringToArray(
+    crypto.decryptData(crypto.encryptData(arr1, url), url)
+  );
+  for (let i = 0; i < arr1.length; i++) {
+    Assert.equal(arr2[i], value[i], "Checking index " + i);
+  }
+});
+
+add_task(function test_decryptDataOutput() {
+  const testString = "2<FPZd";
+  const encrypted = crypto.encryptData(testString);
+
+  const decryptedString = crypto.decryptData(encrypted, null, "string");
+  Assert.equal(
+    decryptedString,
+    testString,
+    "Decrypted string matches initial value"
+  );
+
+  const decryptedBytes = crypto.decryptData(encrypted, null, "bytes");
+  testString.split("").forEach((c, i) => {
+    const code = c.charCodeAt(0);
+    Assert.equal(
+      decryptedBytes[i],
+      code,
+      `Decrypted bytes matches ${c} charCode (${code})`
+    );
+  });
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_PasswordGenerator.js b/toolkit/components/passwordmgr/test/unit/test_PasswordGenerator.js
new file mode 100644
index 0000000000..a5537a4289
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_PasswordGenerator.js
@@ -0,0 +1,122 @@
+"use strict";
+
+const { PasswordGenerator } = ChromeUtils.importESModule(
+  "resource://gre/modules/PasswordGenerator.sys.mjs"
+);
+
+add_task(async function test_shuffleString() {
+  let original = "1234567890";
+  let shuffled = PasswordGenerator._shuffleString(original);
+  notEqual(original, shuffled, "String should have been shuffled");
+});
+
+add_task(async function test_randomUInt8Index() {
+  throws(
+    () => PasswordGenerator._randomUInt8Index(256),
+    /uint8/,
+    "Should throw for larger than uint8"
+  );
+  Assert.ok(
+    Number.isSafeInteger(PasswordGenerator._randomUInt8Index(255)),
+    "Check integer returned"
+  );
+});
+
+add_task(async function test_generatePassword_classes() {
+  let password = PasswordGenerator.generatePassword(
+    /* REQUIRED_CHARACTER_CLASSES */
+
+    { length: 4 }
+  );
+  info(password);
+  equal(password.length, 4, "Check length is correct");
+  Assert.ok(
+    password.match(/[a-km-np-z]/),
+    "Minimal password should include at least one lowercase character"
+  );
+  Assert.ok(
+    password.match(/[A-HJ-NP-Z]/),
+    "Minimal password should include at least one uppercase character"
+  );
+  Assert.ok(
+    password.match(/[2-9]/),
+    "Minimal password should include at least one digit"
+  );
+  Assert.ok(
+    password.match(/[-~!@#$%^&*_+=)}:;"'>,.?\]]/),
+    "Minimal password should include at least one special character"
+  );
+  Assert.ok(
+    password.match(/^[a-km-np-zA-HJ-NP-Z2-9-~!@#$%^&*_+=)}:;"'>,.?\]]+$/),
+    "All characters should be in the expected set"
+  );
+});
+
+add_task(async function test_generatePassword_length() {
+  let password = PasswordGenerator.generatePassword({ length: 5 });
+  info(password);
+  equal(password.length, 5, "Check length is correct");
+
+  password = PasswordGenerator.generatePassword({ length: 3 });
+  equal(password.length, 4, "Minimum generated length is 4");
+
+  password = PasswordGenerator.generatePassword({ length: Math.pow(2, 8) });
+  equal(
+    password.length,
+    Math.pow(2, 8) - 1,
+    "Maximum generated length is Math.pow(2, 8) - 1 "
+  );
+
+  Assert.ok(
+    password.match(/^[a-km-np-zA-HJ-NP-Z2-9-~!@#$%^&*_+=)}:;"'>,.?\]]+$/),
+    "All characters should be in the expected set"
+  );
+});
+
+add_task(async function test_generatePassword_defaultLength() {
+  let password = PasswordGenerator.generatePassword({});
+  info(password);
+  equal(password.length, 15, "Check default length is correct");
+  Assert.ok(
+    password.match(/^[a-km-np-zA-HJ-NP-Z2-9-~!@#$%^&*_+=)}:;"'>,.?\]]{15}$/),
+    "All characters should be in the expected set"
+  );
+});
+
+add_task(
+  async function test_generatePassword_immutableDefaultRequiredClasses() {
+    // We need to escape our special characters since some of them
+    // have special meaning in regex.
+    let specialCharacters = PasswordGenerator._getSpecialCharacters();
+    let escapedSpecialCharacters = specialCharacters.replace(
+      /[.*\-+?^${}()|[\]\\]/g,
+      "\\$&"
+    );
+    specialCharacters = new RegExp(`[${escapedSpecialCharacters}]`);
+    let rules = new Map();
+    rules.set("required", ["special"]);
+    let password = PasswordGenerator.generatePassword({ rules });
+    equal(password.length, 15, "Check default length is correct");
+    Assert.ok(
+      password.match(specialCharacters),
+      "Password should include special character."
+    );
+    let allCharacters = new RegExp(
+      `[a-km-np-zA-HJ-NP-Z2-9 ${escapedSpecialCharacters}]{15}`
+    );
+    Assert.ok(
+      password.match(allCharacters),
+      "All characters should be in the expected set"
+    );
+    password = PasswordGenerator.generatePassword({});
+    equal(password.length, 15, "Check default length is correct");
+    Assert.ok(
+      password.match(specialCharacters),
+      "Password should include special character."
+    );
+    Assert.ok(
+      password.match(/^[a-km-np-zA-HJ-NP-Z2-9-~!@#$%^&*_+=)}:;"'>,.?\]]{15}$/),
+      "All characters, minus special characters, should be in the expected set"
+    );
+  }
+);
diff --git a/toolkit/components/passwordmgr/test/unit/test_PasswordRulesManager_generatePassword.js b/toolkit/components/passwordmgr/test/unit/test_PasswordRulesManager_generatePassword.js
new file mode 100644
index 0000000000..88520769cf
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_PasswordRulesManager_generatePassword.js
@@ -0,0 +1,523 @@
+/**
+ * Test PasswordRulesManager.generatePassword()
+ */
+
+"use strict";
+const { PasswordGenerator } = ChromeUtils.importESModule(
+  "resource://gre/modules/PasswordGenerator.sys.mjs"
+);
+const { PasswordRulesManagerParent } = ChromeUtils.importESModule(
+  "resource://gre/modules/PasswordRulesManager.sys.mjs"
+);
+const { PasswordRulesParser } = ChromeUtils.importESModule(
+  "resource://gre/modules/PasswordRulesParser.sys.mjs"
+);
+const { RemoteSettings } = ChromeUtils.importESModule(
+  "resource://services-settings/remote-settings.sys.mjs"
+);
+const { TelemetryTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/TelemetryTestUtils.sys.mjs"
+);
+
+Services.prefs.setBoolPref(
+  "toolkit.telemetry.testing.overrideProductsCheck",
+  true
+);
+
+const IMPROVED_RULES_COLLECTION = "password-rules";
+
+function getRulesForRecord(records, baseOrigin) {
+  let rules;
+  for (let record of records) {
+    if (record.Domain === baseOrigin) {
+      rules = record["password-rules"];
+      break;
+    }
+  }
+  return rules;
+}
+
+add_task(async function test_verify_password_rules() {
+  const testCases = [
+    { maxlength: 12 },
+    { minlength: 4, maxlength: 32 },
+    { required: ["lower"] },
+    { required: ["upper"] },
+    { required: ["digit"] },
+    { required: ["special"] },
+    { required: ["*", "$", "@", "_", "B", "Q"] },
+    { required: ["lower", "upper", "special"] },
+    { "max-consecutive": 2 },
+    {
+      minlength: 8,
+      required: [
+        "digit",
+        [
+          "-",
+          " ",
+          "!",
+          '"',
+          "#",
+          "$",
+          "&",
+          "'",
+          "(",
+          ")",
+          "*",
+          "+",
+          ",",
+          ".",
+          ":",
+          ";",
+          "<",
+          "=",
+          ">",
+          "?",
+          "@",
+          "[",
+          "^",
+          "_",
+          "`",
+          "{",
+          "|",
+          "}",
+          "~",
+          "]",
+        ],
+      ],
+    },
+    { minlength: 8, maxlength: 16, required: ["lower", "upper", "digit"] },
+    {
+      minlength: 8,
+      maxlength: 20,
+      required: ["lower", "upper", "digit"],
+      "max-consecutive": 2,
+    },
+  ];
+
+  for (let test of testCases) {
+    let mapOfRules = new Map();
+    let rules = ``;
+    for (let testRules in test) {
+      mapOfRules.set(testRules, test[testRules]);
+      if (test[testRules] === "required" && test[testRules].includes("*$")) {
+        rules += `${testRules}: ${test[testRules].join("")}`;
+      } else {
+        rules += `${testRules}: ${test[testRules]};`;
+      }
+    }
+    let generatedPassword = PasswordGenerator.generatePassword({
+      rules: mapOfRules,
+    });
+    verifyPassword(rules, generatedPassword);
+  }
+});
+
+/**
+ * Note: We do not test the "allowed" property in these tests.
+ * This is because a password can still be valid even if there is not a character from
+ * the "allowed" list.
+ * If a character, or character class, is required, then it should be marked as such.
+ * */
+
+add_task(async function test_generatePassword_many_rules() {
+  // Force password generation to be enabled.
+  Services.prefs.setBoolPref("signon.generation.available", true);
+  Services.prefs.setBoolPref("signon.generation.enabled", true);
+  Services.prefs.setBoolPref("signon.improvedPasswordRules.enabled", true);
+  // TEST_ORIGIN emulates the browsingContext.currentWindowGlobal.documentURI variable in LoginManagerParent
+  // and so it should always be a correctly formed URI when working with
+  // the PasswordRulesParser and PasswordRulesManager modules
+  const TEST_ORIGIN = Services.io.newURI("https://example.com");
+
+  // TEST_BASE_ORIGIN is how each domain is stored in RemoteSettings, and so
+  // we need this in order to parse out the particular password rules we're verifying
+  const TEST_BASE_ORIGIN = "example.com";
+  await LoginTestUtils.remoteSettings.setupImprovedPasswordRules();
+  const records = await RemoteSettings(IMPROVED_RULES_COLLECTION).get();
+
+  let rules = getRulesForRecord(records, TEST_BASE_ORIGIN);
+
+  rules = PasswordRulesParser.parsePasswordRules(rules);
+  Assert.ok(rules.length, "Rules should exist after parsing");
+
+  let PRMP = new PasswordRulesManagerParent();
+  Assert.ok(PRMP.generatePassword, "PRMP.generatePassword exists");
+
+  let generatedPassword = await PRMP.generatePassword(TEST_ORIGIN);
+  Assert.ok(generatedPassword, "A password was generated");
+
+  verifyPassword(rules, generatedPassword);
+
+  await LoginTestUtils.remoteSettings.cleanImprovedPasswordRules();
+});
+
+add_task(async function test_generatePassword_all_characters_allowed() {
+  // Force password generation to be enabled.
+  Services.prefs.setBoolPref("signon.generation.available", true);
+  Services.prefs.setBoolPref("signon.generation.enabled", true);
+  Services.prefs.setBoolPref("signon.improvedPasswordRules.enabled", true);
+  // TEST_ORIGIN emulates the browsingContext.currentWindowGlobal.documentURI variable in LoginManagerParent
+  // and so it should always be a correctly formed URI when working with
+  // the PasswordRulesParser and PasswordRulesManager modules
+  const TEST_ORIGIN = Services.io.newURI("https://example.com");
+
+  // TEST_BASE_ORIGIN is how each domain is stored in RemoteSettings, and so
+  // we need this in order to parse out the particular password rules we're verifying
+  const TEST_BASE_ORIGIN = "example.com";
+  const TEST_RULES = "minlength: 6; maxlength: 12;";
+  await LoginTestUtils.remoteSettings.setupImprovedPasswordRules(
+    TEST_BASE_ORIGIN,
+    TEST_RULES
+  );
+  const records = await RemoteSettings(IMPROVED_RULES_COLLECTION).get();
+
+  let rules = getRulesForRecord(records, TEST_BASE_ORIGIN);
+
+  rules = PasswordRulesParser.parsePasswordRules(rules);
+  Assert.ok(rules.length, "Rules should exist after parsing");
+
+  let PRMP = new PasswordRulesManagerParent();
+  Assert.ok(PRMP.generatePassword, "PRMP.generatePassword exists");
+
+  let generatedPassword = await PRMP.generatePassword(TEST_ORIGIN);
+  Assert.ok(generatedPassword, "A password was generated");
+
+  verifyPassword(rules, generatedPassword);
+
+  await LoginTestUtils.remoteSettings.cleanImprovedPasswordRules();
+});
+
+add_task(async function test_generatePassword_required_special_character() {
+  // Force password generation to be enabled.
+  Services.prefs.setBoolPref("signon.generation.available", true);
+  Services.prefs.setBoolPref("signon.generation.enabled", true);
+  Services.prefs.setBoolPref("signon.improvedPasswordRules.enabled", true);
+  // TEST_ORIGIN emulates the browsingContext.currentWindowGlobal.documentURI variable in LoginManagerParent
+  // and so it should always be a correctly formed URI when working with
+  // the PasswordRulesParser and PasswordRulesManager modules
+  const TEST_ORIGIN = Services.io.newURI("https://example.com");
+
+  // TEST_BASE_ORIGIN is how each domain is stored in RemoteSettings, and so
+  // we need this in order to parse out the particular password rules we're verifying
+  const TEST_BASE_ORIGIN = "example.com";
+  const TEST_RULES = "required: special";
+  await LoginTestUtils.remoteSettings.setupImprovedPasswordRules(
+    TEST_BASE_ORIGIN,
+    TEST_RULES
+  );
+  const records = await RemoteSettings(IMPROVED_RULES_COLLECTION).get();
+
+  let rules = getRulesForRecord(records, TEST_BASE_ORIGIN);
+
+  rules = PasswordRulesParser.parsePasswordRules(rules);
+  Assert.ok(rules.length, "Rules should exist after parsing");
+
+  let PRMP = new PasswordRulesManagerParent();
+  Assert.ok(PRMP.generatePassword, "PRMP.generatePassword exists");
+
+  let generatedPassword = await PRMP.generatePassword(TEST_ORIGIN);
+  Assert.ok(generatedPassword, "A password was generated");
+
+  verifyPassword(TEST_RULES, generatedPassword);
+});
+
+add_task(
+  async function test_generatePassword_with_arbitrary_required_characters() {
+    // Force password generation to be enabled.
+    Services.prefs.setBoolPref("signon.generation.available", true);
+    Services.prefs.setBoolPref("signon.generation.enabled", true);
+    Services.prefs.setBoolPref("signon.improvedPasswordRules.enabled", true);
+    // TEST_ORIGIN emulates the browsingContext.currentWindowGlobal.documentURI variable in LoginManagerParent
+    // and so it should always be a correctly formed URI when working with
+    // the PasswordRulesParser and PasswordRulesManager modules
+    const TEST_ORIGIN = Services.io.newURI("https://example.com");
+
+    // TEST_BASE_ORIGIN is how each domain is stored in RemoteSettings, and so
+    // we need this in order to parse out the particular password rules we're verifying
+    const TEST_BASE_ORIGIN = "example.com";
+    const REQUIRED_ARBITRARY_CHARACTERS = "!#$@*()_+=";
+    // We use an extremely long password to ensure there are no invalid characters generated in the password.
+    // This ensures we exhaust all of "allRequiredCharacters" in PasswordGenerator.jsm.
+    // Otherwise, there's a small chance a "," may have been added to "allRequiredCharacters"
+    // which will generate an invalid password in this case.
+    const TEST_RULES = `required: [${REQUIRED_ARBITRARY_CHARACTERS}], upper, lower; maxlength: 255; minlength: 255;`;
+    await LoginTestUtils.remoteSettings.setupImprovedPasswordRules(
+      TEST_BASE_ORIGIN,
+      TEST_RULES
+    );
+    const records = await RemoteSettings(IMPROVED_RULES_COLLECTION).get();
+
+    let rules = getRulesForRecord(records, TEST_BASE_ORIGIN);
+
+    rules = PasswordRulesParser.parsePasswordRules(rules);
+    Assert.ok(rules.length, "Rules should exist after parsing");
+
+    let PRMP = new PasswordRulesManagerParent();
+    Assert.ok(PRMP.generatePassword, "PRMP.generatePassword exists");
+
+    let generatedPassword = await PRMP.generatePassword(TEST_ORIGIN);
+    generatedPassword = await PRMP.generatePassword(TEST_ORIGIN);
+    Assert.ok(generatedPassword, "A password was generated");
+
+    verifyPassword(TEST_RULES, generatedPassword);
+
+    let specialCharacters = PasswordGenerator._getSpecialCharacters();
+    let digits = PasswordGenerator._getDigits();
+    // Additional verification for this password case since
+    // we want to ensure no extra special characters and no digits are generated.
+    let disallowedSpecialCharacters = "";
+    for (let char of specialCharacters) {
+      if (!REQUIRED_ARBITRARY_CHARACTERS.includes(char)) {
+        disallowedSpecialCharacters += char;
+      }
+    }
+    for (let char of disallowedSpecialCharacters) {
+      Assert.ok(
+        !generatedPassword.includes(char),
+        "Password must not contain any disallowed special characters: " + char
+      );
+    }
+    for (let char of digits) {
+      Assert.ok(
+        !generatedPassword.includes(char),
+        "Password must not contain any digits: " + char
+      );
+    }
+  }
+);
+
+// Checks the "www4.prepaid.bankofamerica.com" case to ensure the rules are found
+add_task(async function test_generatePassword_subdomain_rule() {
+  const testCases = [
+    {
+      uri: "https://www4.test.example.com",
+      rulesDomain: "example.com",
+      shouldApplyPWRule: true,
+    },
+    {
+      uri: "https://test.example.com",
+      rulesDomain: "example.com",
+      shouldApplyPWRule: true,
+    },
+    {
+      uri: "https://example.com",
+      rulesDomain: "example.com",
+      shouldApplyPWRule: true,
+    },
+    {
+      uri: "https://www4.test.example.com",
+      rulesDomain: "test.example.com",
+      shouldApplyPWRule: true,
+    },
+    {
+      uri: "https://test.example.com",
+      rulesDomain: "test.example.com",
+      shouldApplyPWRule: true,
+    },
+    {
+      uri: "https://example.com",
+      rulesDomain: "test.example.com",
+      shouldApplyPWRule: false,
+    },
+    {
+      uri: "https://evil.com",
+      rulesDomain: "example.com",
+      shouldApplyPWRule: false,
+    },
+    {
+      uri: "https://evil.example.com",
+      rulesDomain: "test.example.com",
+      shouldApplyPWRule: false,
+    },
+    {
+      uri: "https://test.example.com.cn",
+      rulesDomain: "test.example.com",
+      shouldApplyPWRule: false,
+    },
+    {
+      uri: "https://eviltest.example.com",
+      rulesDomain: "test.example.com",
+      shouldApplyPWRule: false,
+    },
+  ];
+  const TEST_RULES = "required: special; maxlength: 12;";
+
+  for (let test of testCases) {
+    await LoginTestUtils.remoteSettings.setupImprovedPasswordRules(
+      test.rulesDomain,
+      TEST_RULES
+    );
+    const TEST_ORIGIN = Services.io.newURI(test.uri);
+    const TEST_BASE_ORIGIN = test.rulesDomain;
+    const records = await RemoteSettings(IMPROVED_RULES_COLLECTION).get();
+
+    let rules = getRulesForRecord(records, TEST_BASE_ORIGIN);
+
+    rules = PasswordRulesParser.parsePasswordRules(rules);
+    Assert.ok(rules.length, "Rules should exist after parsing");
+
+    let PRMP = new PasswordRulesManagerParent();
+
+    let generatedPassword = await PRMP.generatePassword(TEST_ORIGIN);
+    Assert.ok(
+      generatedPassword,
+      "A password was generated for URI: " + test.uri
+    );
+
+    // If a rule should be applied, we verify the password has all the required classes in the generated password.
+    if (test.shouldApplyPWRule) {
+      verifyPassword(rules, generatedPassword);
+    }
+  }
+});
+
+add_task(async function test_improved_password_rules_telemetry() {
+  // Force password generation to be enabled.
+  Services.prefs.setBoolPref("signon.generation.available", true);
+  Services.prefs.setBoolPref("signon.generation.enabled", true);
+  Services.prefs.setBoolPref("signon.improvedPasswordRules.enabled", true);
+
+  const IMPROVED_PASSWORD_GENERATION_HISTOGRAM =
+    "PWMGR_NUM_IMPROVED_GENERATED_PASSWORDS";
+
+  // Clear out the previous pings from this test
+  let snapshot = TelemetryTestUtils.getAndClearHistogram(
+    IMPROVED_PASSWORD_GENERATION_HISTOGRAM
+  );
+
+  // TEST_ORIGIN emulates the browsingContext.currentWindowGlobal.documentURI variable in LoginManagerParent
+  // and so it should always be a correctly formed URI when working with
+  // the PasswordRulesParser and PasswordRulesManager modules
+  let TEST_ORIGIN = Services.io.newURI("https://example.com");
+  await LoginTestUtils.remoteSettings.setupImprovedPasswordRules();
+
+  let PRMP = new PasswordRulesManagerParent();
+
+  // Generate a password with custom rules,
+  // so we should send a ping to the custom rules bucket (position 1).
+  let generatedPassword = await PRMP.generatePassword(TEST_ORIGIN);
+  Assert.ok(generatedPassword, "A password was generated");
+
+  TelemetryTestUtils.assertHistogram(snapshot, 1, 1);
+
+  TEST_ORIGIN = Services.io.newURI("https://otherexample.com");
+  // Generate a password with default rules,
+  // so we should send a ping to the default rules bucket (position 0).
+  snapshot = TelemetryTestUtils.getAndClearHistogram(
+    IMPROVED_PASSWORD_GENERATION_HISTOGRAM
+  );
+  generatedPassword = await PRMP.generatePassword(TEST_ORIGIN);
+  Assert.ok(generatedPassword, "A password was generated");
+
+  TelemetryTestUtils.assertHistogram(snapshot, 0, 1);
+});
+
+function checkCharacters(password, _characters) {
+  let containsCharacters = false;
+  let testString = _characters.join("");
+  for (let character of password) {
+    containsCharacters = testString.includes(character);
+    if (containsCharacters) {
+      return containsCharacters;
+    }
+  }
+  return containsCharacters;
+}
+
+function checkConsecutiveCharacters(generatePassword, value) {
+  let findMaximumRepeating = str => {
+    let max = 0;
+    for (let start = 0, end = 1; end < str.length; ) {
+      if (str[end] === str[start]) {
+        if (max < end - start + 1) {
+          max = end - start + 1;
+          if (max > value) {
+            return max;
+          }
+        }
+        end++;
+      } else {
+        start = end++;
+      }
+    }
+    return max;
+  };
+  let consecutiveCharacters = findMaximumRepeating(generatePassword);
+  if (consecutiveCharacters <= value) {
+    return true;
+  }
+  return false;
+}
+
+function verifyPassword(rules, generatedPassword) {
+  const UPPER_CASE_ALPHA = PasswordGenerator._getUpperCaseCharacters();
+  const LOWER_CASE_ALPHA = PasswordGenerator._getLowerCaseCharacters();
+  const DIGITS = PasswordGenerator._getDigits();
+  const SPECIAL_CHARACTERS = PasswordGenerator._getSpecialCharacters();
+  for (let rule of rules) {
+    let { _name, value } = rule;
+    if (_name === "required") {
+      for (let required of value) {
+        if (required._name === "upper") {
+          let _checkUppercase = new RegExp(`[${UPPER_CASE_ALPHA}]`);
+          Assert.ok(
+            generatedPassword.match(_checkUppercase),
+            "Password must include upper case letter"
+          );
+        } else if (required._name === "lower") {
+          let _checkLowercase = new RegExp(`[${LOWER_CASE_ALPHA}]`);
+          Assert.ok(
+            generatedPassword.match(_checkLowercase),
+            "Password must include lower case letter"
+          );
+        } else if (required._name === "digit") {
+          let _checkDigits = new RegExp(`[${DIGITS}]`);
+          Assert.ok(
+            generatedPassword.match(_checkDigits),
+            "Password must include digits"
+          );
+          generatedPassword.match(_checkDigits);
+        } else if (required._name === "special") {
+          // We need to escape our special characters since some of them
+          // have special meaning in regex.
+          let escapedSpecialCharacters = SPECIAL_CHARACTERS.replace(
+            /[.*\-+?^${}()|[\]\\]/g,
+            "\\$&"
+          );
+          let _checkSpecial = new RegExp(`[${escapedSpecialCharacters}]`);
+          Assert.ok(
+            generatedPassword.match(_checkSpecial),
+            "Password must include special character"
+          );
+        } else {
+          // Nested destructing of the value object in the characters case
+          let [{ _characters }] = value;
+
+          // We can't use regex to do a quick check here since the
+          // required characters could be characters that need to be escaped
+          // in order for the regex to work properly ([]"^...etc)
+          Assert.ok(
+            checkCharacters(generatedPassword, _characters),
+            `Password must contain one of the following characters: ${_characters}`
+          );
+        }
+      }
+    } else if (_name === "minlength") {
+      Assert.ok(
+        generatedPassword.length >= value,
+        `Password should have a minimum length of ${value}`
+      );
+    } else if (_name === "maxlength") {
+      Assert.ok(
+        generatedPassword.length <= value,
+        `Password should have a maximum length of ${value}`
+      );
+    } else if (_name === "max-consecutive") {
+      Assert.ok(
+        checkConsecutiveCharacters(generatedPassword, value),
+        `Password must not contain more than ${value} consecutive characters`
+      );
+    }
+  }
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_context_menu.js b/toolkit/components/passwordmgr/test/unit/test_context_menu.js
new file mode 100644
index 0000000000..c0947ea22b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_context_menu.js
@@ -0,0 +1,345 @@
+/**
+ * Test the password manager context menu.
+ */
+
+"use strict";
+
+const { LoginManagerContextMenu } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerContextMenu.sys.mjs"
+);
+
+const dateAndTimeFormatter = new Services.intl.DateTimeFormat(undefined, {
+  dateStyle: "medium",
+});
+
+const ORIGIN_HTTP_EXAMPLE_ORG = "http://example.org";
+const ORIGIN_HTTPS_EXAMPLE_ORG = "https://example.org";
+const ORIGIN_HTTPS_EXAMPLE_ORG_8080 = "https://example.org:8080";
+
+const FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1 = formLogin({
+  formActionOrigin: ORIGIN_HTTPS_EXAMPLE_ORG,
+  guid: "FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1",
+  origin: ORIGIN_HTTPS_EXAMPLE_ORG,
+});
+
+// HTTP version of the above
+const FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P1 = formLogin({
+  formActionOrigin: ORIGIN_HTTP_EXAMPLE_ORG,
+  guid: "FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P1",
+  origin: ORIGIN_HTTP_EXAMPLE_ORG,
+});
+
+// Same as above but with a different password
+const FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P2 = formLogin({
+  formActionOrigin: ORIGIN_HTTP_EXAMPLE_ORG,
+  guid: "FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P2",
+  origin: ORIGIN_HTTP_EXAMPLE_ORG,
+  password: "pass2",
+});
+
+// Non-default port
+
+const FORM_LOGIN_HTTPS_EXAMPLE_ORG_8080_U1_P2 = formLogin({
+  formActionOrigin: ORIGIN_HTTPS_EXAMPLE_ORG_8080,
+  guid: "FORM_LOGIN_HTTPS_EXAMPLE_ORG_8080_U1_P2",
+  origin: ORIGIN_HTTPS_EXAMPLE_ORG_8080,
+  password: "pass2",
+});
+
+// HTTP Auth.
+
+const HTTP_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1 = authLogin({
+  guid: "FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1",
+  origin: ORIGIN_HTTPS_EXAMPLE_ORG,
+});
+
+ChromeUtils.defineLazyGetter(this, "_stringBundle", function () {
+  return Services.strings.createBundle(
+    "chrome://passwordmgr/locale/passwordmgr.properties"
+  );
+});
+
+/**
+ * Prepare data for the following tests.
+ */
+add_task(async function test_initialize() {
+  Services.prefs.setBoolPref("signon.schemeUpgrades", true);
+});
+
+add_task(async function test_sameOriginBothHTTPAndHTTPSDeduped() {
+  await runTestcase({
+    formOrigin: FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1.origin,
+    savedLogins: [FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1],
+    expectedItems: [
+      {
+        login: FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+      },
+    ],
+  });
+});
+
+add_task(async function test_sameOriginOnlyHTTPS_noUsername() {
+  let loginWithoutUsername = FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1.clone();
+  loginWithoutUsername.QueryInterface(Ci.nsILoginMetaInfo).guid = "no-username";
+  loginWithoutUsername.username = "";
+  await runTestcase({
+    formOrigin: loginWithoutUsername.origin,
+    savedLogins: [loginWithoutUsername],
+    expectedItems: [
+      {
+        login: loginWithoutUsername,
+        time: true,
+      },
+    ],
+  });
+});
+
+add_task(async function test_sameOriginOnlyHTTP() {
+  await runTestcase({
+    formOrigin: FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P1.origin,
+    savedLogins: [FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P1],
+    expectedItems: [
+      {
+        login: FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P1,
+      },
+    ],
+  });
+});
+
+// Scheme upgrade/downgrade tasks
+
+add_task(async function test_sameOriginDedupeSchemeUpgrade() {
+  await runTestcase({
+    formOrigin: FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1.origin,
+    savedLogins: [
+      FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+      FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P1,
+    ],
+    expectedItems: [
+      {
+        login: FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+      },
+    ],
+  });
+});
+
+add_task(async function test_sameOriginSchemeDowngrade() {
+  // Should have no https: when formOrigin is https:
+  await runTestcase({
+    formOrigin: FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P1.origin,
+    savedLogins: [
+      FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+      FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P1,
+    ],
+    expectedItems: [
+      {
+        login: FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P1,
+      },
+    ],
+  });
+});
+
+add_task(async function test_sameOriginNotShadowedSchemeUpgrade() {
+  await runTestcase({
+    formOrigin: FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1.origin,
+    savedLogins: [
+      FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+      FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P2, // Different password
+    ],
+    expectedItems: [
+      {
+        login: FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+        time: true,
+      },
+      {
+        login: FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P2,
+        time: true,
+      },
+    ],
+  });
+});
+
+add_task(async function test_sameOriginShadowedSchemeDowngrade() {
+  // Should have no https: when formOrigin is https:
+  await runTestcase({
+    formOrigin: FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P1.origin,
+    savedLogins: [
+      FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+      FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P2, // Different password
+    ],
+    expectedItems: [
+      {
+        login: FORM_LOGIN_HTTP_EXAMPLE_ORG_U1_P2,
+      },
+    ],
+  });
+});
+
+// Non-default port tasks
+
+add_task(async function test_sameDomainDifferentPort_onDefault() {
+  await runTestcase({
+    formOrigin: FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1.origin,
+    savedLogins: [
+      FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+      FORM_LOGIN_HTTPS_EXAMPLE_ORG_8080_U1_P2,
+    ],
+    expectedItems: [
+      {
+        login: FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+      },
+    ],
+  });
+});
+
+add_task(async function test_sameDomainDifferentPort_onNonDefault() {
+  await runTestcase({
+    // Swap the formOrigin compared to above
+    formOrigin: FORM_LOGIN_HTTPS_EXAMPLE_ORG_8080_U1_P2.origin,
+    savedLogins: [
+      FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+      FORM_LOGIN_HTTPS_EXAMPLE_ORG_8080_U1_P2,
+    ],
+    expectedItems: [
+      {
+        login: FORM_LOGIN_HTTPS_EXAMPLE_ORG_8080_U1_P2,
+      },
+    ],
+  });
+});
+
+// HTTP auth. suggestions
+
+add_task(async function test_sameOriginOnlyHTTPAuth() {
+  await runTestcase({
+    formOrigin: FORM_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1.origin,
+    savedLogins: [HTTP_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1],
+    expectedItems: [
+      {
+        login: HTTP_LOGIN_HTTPS_EXAMPLE_ORG_U1_P1,
+      },
+    ],
+  });
+});
+
+// Helpers
+
+function formLogin(modifications = {}) {
+  let mods = Object.assign(
+    {},
+    {
+      timePasswordChanged: 1573821296000,
+    },
+    modifications
+  );
+  return TestData.formLogin(mods);
+}
+
+function authLogin(modifications = {}) {
+  let mods = Object.assign(
+    {},
+    {
+      timePasswordChanged: 1573821296000,
+    },
+    modifications
+  );
+  return TestData.authLogin(mods);
+}
+
+/**
+ * Tests if the LoginManagerContextMenu returns the correct login items.
+ */
+async function runTestcase({ formOrigin, savedLogins, expectedItems }) {
+  const DOCUMENT_CONTENT = "<form><input id='pw' type=password></form>";
+
+  await Services.logins.addLogins(savedLogins);
+
+  // Create the logins menuitems fragment.
+  let { fragment, document } = createLoginsFragment(
+    formOrigin,
+    DOCUMENT_CONTENT
+  );
+
+  if (!expectedItems.length) {
+    Assert.ok(fragment === null, "Null returned. No logins were found.");
+    return;
+  }
+  let actualItems = [...fragment.children];
+
+  // Check if the items are those expected to be listed.
+  checkLoginItems(actualItems, expectedItems);
+
+  document.body.appendChild(fragment);
+
+  // Try to clear the fragment.
+  LoginManagerContextMenu.clearLoginsFromMenu(document);
+  Assert.equal(
+    document.querySelectorAll("menuitem").length,
+    0,
+    "All items correctly cleared."
+  );
+
+  Services.logins.removeAllUserFacingLogins();
+}
+
+/**
+ * Create a fragment with a menuitem for each login.
+ */
+function createLoginsFragment(url, content) {
+  const CHROME_URL = "chrome://mock-chrome/content/";
+
+  // Create a mock document.
+  let document = MockDocument.createTestDocument(
+    CHROME_URL,
+    content,
+    undefined,
+    true
+  );
+
+  // We also need a simple mock Browser object for this test.
+  let browser = {
+    ownerDocument: document,
+  };
+
+  let formOrigin = LoginHelper.getLoginOrigin(url);
+  return {
+    document,
+    fragment: LoginManagerContextMenu.addLoginsToMenu(
+      null,
+      browser,
+      formOrigin
+    ),
+  };
+}
+
+function checkLoginItems(actualItems, expectedDetails) {
+  for (let [i, expectedDetail] of expectedDetails.entries()) {
+    let actualElement = actualItems[i];
+
+    Assert.equal(actualElement.localName, "menuitem", "Check localName");
+
+    let expectedLabel = expectedDetail.login.username;
+    if (!expectedLabel) {
+      expectedLabel += _stringBundle.GetStringFromName("noUsername");
+    }
+    if (expectedDetail.time) {
+      expectedLabel +=
+        " (" +
+        dateAndTimeFormatter.format(
+          new Date(expectedDetail.login.timePasswordChanged)
+        ) +
+        ")";
+    }
+    Assert.equal(
+      actualElement.getAttribute("label"),
+      expectedLabel,
+      `Check label ${i}`
+    );
+  }
+
+  Assert.equal(
+    actualItems.length,
+    expectedDetails.length,
+    "Should have the correct number of menu items"
+  );
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_dedupeLogins.js b/toolkit/components/passwordmgr/test/unit/test_dedupeLogins.js
new file mode 100644
index 0000000000..f0305e3c69
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_dedupeLogins.js
@@ -0,0 +1,411 @@
+/**
+ * Test LoginHelper.dedupeLogins
+ */
+
+"use strict";
+
+const DOMAIN1_HTTP_TO_HTTP_U1_P1 = TestData.formLogin({
+  timePasswordChanged: 3000,
+  timeLastUsed: 2000,
+});
+const DOMAIN1_HTTP_TO_HTTP_U1_P2 = TestData.formLogin({
+  password: "password two",
+});
+const DOMAIN2_HTTP_TO_HTTP_U2_P2 = TestData.formLogin({
+  origin: "http://www4.example.com",
+  formActionOrigin: "http://www4.example.com",
+  password: "password two",
+  username: "username two",
+});
+
+const DOMAIN1_HTTPS_TO_HTTP_U1_P1 = TestData.formLogin({
+  formActionOrigin: "http://www.example.com",
+  origin: "https://www3.example.com",
+  timePasswordChanged: 4000,
+  timeLastUsed: 1000,
+});
+const DOMAIN1_HTTPS_TO_HTTPS_U1_P1 = TestData.formLogin({
+  formActionOrigin: "https://www.example.com",
+  origin: "https://www3.example.com",
+  timePasswordChanged: 4000,
+  timeLastUsed: 1000,
+});
+
+const DOMAIN1_HTTPS_TO_EMPTY_U1_P1 = TestData.formLogin({
+  formActionOrigin: "",
+  origin: "https://www3.example.com",
+});
+const DOMAIN1_HTTPS_TO_EMPTYU_P1 = TestData.formLogin({
+  origin: "https://www3.example.com",
+  username: "",
+});
+const DOMAIN1_HTTP_AUTH = TestData.authLogin({
+  origin: "http://www3.example.com",
+});
+const DOMAIN1_HTTPS_AUTH = TestData.authLogin({
+  origin: "https://www3.example.com",
+});
+const DOMAIN1_HTTPS_LOGIN = TestData.formLogin({
+  origin: "https://www3.example.com",
+  formActionOrigin: "https://www3.example.com",
+});
+const DOMAIN1_HTTP_LOGIN = TestData.formLogin({
+  origin: "http://www3.example.com",
+  formActionOrigin: "http://www3.example.com",
+});
+const DOMAIN1_HTTPS_NONSTANDARD_PORT1 = TestData.formLogin({
+  origin: "https://www3.example.com:8001",
+  formActionOrigin: "https://www3.example.com:8001",
+});
+const DOMAIN1_HTTPS_NONSTANDARD_PORT2 = TestData.formLogin({
+  origin: "https://www3.example.com:8008",
+  formActionOrigin: "https://www3.example.com:8008",
+});
+const DOMAIN2_HTTPS_LOGIN = TestData.formLogin({
+  origin: "https://www4.example.com",
+  formActionOrigin: "https://www4.example.com",
+});
+const DOMAIN2_HTTPS_LOGIN_NEWER = TestData.formLogin({
+  origin: "https://www4.example.com",
+  formActionOrigin: "https://www4.example.com",
+  timePasswordChanged: 4000,
+  timeLastUsed: 4000,
+});
+const DOMAIN2_HTTPS_TO_HTTPS_U2_P2 = TestData.formLogin({
+  origin: "https://www4.example.com",
+  formActionOrigin: "https://www4.example.com",
+  password: "password two",
+  username: "username two",
+});
+
+add_task(function test_dedupeLogins() {
+  // [description, expectedOutput, dedupe arg. 0, dedupe arg 1, ...]
+  let testcases = [
+    [
+      "exact dupes",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      undefined,
+      [], // force no resolveBy logic to test behavior of preferring the first..
+    ],
+    [
+      "default uniqueKeys is un + pw",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P2],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P2],
+      undefined,
+      [],
+    ],
+    [
+      "same usernames, different passwords, dedupe username only",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P2],
+      ["username"],
+      [],
+    ],
+    [
+      "same un+pw, different scheme",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      undefined,
+      [],
+    ],
+    [
+      "same un+pw, different scheme, reverse order",
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      undefined,
+      [],
+    ],
+    [
+      "same un+pw, different scheme, include origin",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      ["origin", "username", "password"],
+      [],
+    ],
+    [
+      "empty username is not deduped with non-empty",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_EMPTYU_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_EMPTYU_P1],
+      undefined,
+      [],
+    ],
+    [
+      "empty username is deduped with same passwords",
+      [DOMAIN1_HTTPS_TO_EMPTYU_P1],
+      [DOMAIN1_HTTPS_TO_EMPTYU_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      ["password"],
+      [],
+    ],
+    [
+      "mix of form and HTTP auth",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTP_AUTH],
+      undefined,
+      [],
+    ],
+  ];
+
+  for (let tc of testcases) {
+    let description = tc.shift();
+    let expected = tc.shift();
+    let actual = LoginHelper.dedupeLogins(...tc);
+    Assert.strictEqual(actual.length, expected.length, `Check: ${description}`);
+    for (let [i, login] of expected.entries()) {
+      Assert.strictEqual(actual[i], login, `Check index ${i}`);
+    }
+  }
+});
+
+add_task(async function test_dedupeLogins_resolveBy() {
+  Assert.ok(
+    DOMAIN1_HTTP_TO_HTTP_U1_P1.timeLastUsed >
+      DOMAIN1_HTTPS_TO_HTTP_U1_P1.timeLastUsed,
+    "Sanity check timeLastUsed difference"
+  );
+  Assert.ok(
+    DOMAIN1_HTTP_TO_HTTP_U1_P1.timePasswordChanged <
+      DOMAIN1_HTTPS_TO_HTTP_U1_P1.timePasswordChanged,
+    "Sanity check timePasswordChanged difference"
+  );
+  Assert.ok(
+    DOMAIN1_HTTPS_LOGIN.timePasswordChanged <
+      DOMAIN2_HTTPS_LOGIN_NEWER.timePasswordChanged,
+    "Sanity check timePasswordChanged difference"
+  );
+
+  let testcases = [
+    [
+      "default resolveBy is timeLastUsed",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+    ],
+    [
+      "default resolveBy is timeLastUsed, reversed input",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+    ],
+    [
+      "resolveBy timeLastUsed + timePasswordChanged",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      undefined,
+      ["timeLastUsed", "timePasswordChanged"],
+    ],
+    [
+      "resolveBy timeLastUsed + timePasswordChanged, reversed input",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      undefined,
+      ["timeLastUsed", "timePasswordChanged"],
+    ],
+    [
+      "resolveBy timePasswordChanged",
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      undefined,
+      ["timePasswordChanged"],
+    ],
+    [
+      "resolveBy timePasswordChanged, reversed",
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      undefined,
+      ["timePasswordChanged"],
+    ],
+    [
+      "resolveBy timePasswordChanged + timeLastUsed",
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      undefined,
+      ["timePasswordChanged", "timeLastUsed"],
+    ],
+    [
+      "resolveBy timePasswordChanged + timeLastUsed, reversed",
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      undefined,
+      ["timePasswordChanged", "timeLastUsed"],
+    ],
+    [
+      "resolveBy scheme + timePasswordChanged, prefer HTTP",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      undefined,
+      ["scheme", "timePasswordChanged"],
+      DOMAIN1_HTTP_TO_HTTP_U1_P1.origin,
+    ],
+    [
+      "resolveBy scheme + timePasswordChanged, prefer HTTP, reversed input",
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      undefined,
+      ["scheme", "timePasswordChanged"],
+      DOMAIN1_HTTP_TO_HTTP_U1_P1.origin,
+    ],
+    [
+      "resolveBy scheme + timePasswordChanged, prefer HTTPS",
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      undefined,
+      ["scheme", "timePasswordChanged"],
+      DOMAIN1_HTTPS_TO_HTTP_U1_P1.origin,
+    ],
+    [
+      "resolveBy scheme + timePasswordChanged, prefer HTTPS, reversed input",
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTP_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      undefined,
+      ["scheme", "timePasswordChanged"],
+      DOMAIN1_HTTPS_TO_HTTP_U1_P1.origin,
+    ],
+    [
+      "resolveBy scheme HTTP auth",
+      [DOMAIN1_HTTPS_AUTH],
+      [DOMAIN1_HTTP_AUTH, DOMAIN1_HTTPS_AUTH],
+      undefined,
+      ["scheme"],
+      DOMAIN1_HTTPS_AUTH.origin,
+    ],
+    [
+      "resolveBy scheme HTTP auth, reversed input",
+      [DOMAIN1_HTTPS_AUTH],
+      [DOMAIN1_HTTPS_AUTH, DOMAIN1_HTTP_AUTH],
+      undefined,
+      ["scheme"],
+      DOMAIN1_HTTPS_AUTH.origin,
+    ],
+    [
+      "resolveBy scheme, empty form submit URL",
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1],
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTPS_TO_EMPTY_U1_P1],
+      undefined,
+      ["scheme"],
+      DOMAIN1_HTTPS_TO_HTTP_U1_P1.origin,
+    ],
+    [
+      "resolveBy subdomain, different subdomains, same login, subdomain1 preferred",
+      [DOMAIN1_HTTPS_LOGIN],
+      [DOMAIN1_HTTPS_LOGIN, DOMAIN2_HTTPS_LOGIN],
+      undefined,
+      ["subdomain"],
+      DOMAIN1_HTTPS_LOGIN.origin,
+    ],
+    [
+      "resolveBy subdomain, different subdomains, same login, subdomain2 preferred",
+      [DOMAIN2_HTTPS_LOGIN],
+      [DOMAIN1_HTTPS_LOGIN, DOMAIN2_HTTPS_LOGIN],
+      undefined,
+      ["subdomain"],
+      DOMAIN2_HTTPS_LOGIN.origin,
+    ],
+    [
+      "resolveBy subdomain+timePasswordChanged, different subdomains, same login, subdomain1 preferred",
+      [DOMAIN1_HTTPS_LOGIN],
+      [DOMAIN1_HTTPS_LOGIN, DOMAIN2_HTTPS_LOGIN_NEWER],
+      undefined,
+      ["subdomain", "timePasswordChanged"],
+      DOMAIN1_HTTPS_LOGIN.origin,
+    ],
+    [
+      "resolveBy subdomain, same subdomain, different schemes",
+      [DOMAIN1_HTTPS_LOGIN],
+      [DOMAIN1_HTTPS_LOGIN, DOMAIN1_HTTP_LOGIN],
+      undefined,
+      ["subdomain"],
+      DOMAIN1_HTTPS_LOGIN.origin,
+    ],
+    [
+      "resolveBy subdomain, same subdomain, different ports",
+      [DOMAIN1_HTTPS_LOGIN],
+      [
+        DOMAIN1_HTTPS_LOGIN,
+        DOMAIN1_HTTPS_NONSTANDARD_PORT1,
+        DOMAIN1_HTTPS_NONSTANDARD_PORT2,
+      ],
+      undefined,
+      ["subdomain"],
+      DOMAIN1_HTTPS_LOGIN.origin,
+    ],
+    [
+      "resolveBy subdomain, same subdomain, different schemes, different ports",
+      [DOMAIN1_HTTPS_LOGIN],
+      [
+        DOMAIN1_HTTPS_LOGIN,
+        DOMAIN1_HTTPS_NONSTANDARD_PORT1,
+        DOMAIN1_HTTPS_NONSTANDARD_PORT2,
+      ],
+      undefined,
+      ["subdomain"],
+      DOMAIN1_HTTPS_AUTH.origin,
+    ],
+    [
+      "resolveBy matching searchAndDedupeLogins, prefer domain matches then https: scheme over http:",
+      // expected:
+      [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN2_HTTPS_TO_HTTPS_U2_P2],
+      // logins:
+      [
+        DOMAIN1_HTTP_TO_HTTP_U1_P1,
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P1,
+        DOMAIN2_HTTP_TO_HTTP_U2_P2,
+        DOMAIN2_HTTPS_TO_HTTPS_U2_P2,
+      ],
+      // uniqueKeys:
+      undefined,
+      // resolveBy:
+      ["subdomain", "actionOrigin", "scheme", "timePasswordChanged"],
+      // preferredOrigin:
+      DOMAIN1_HTTPS_TO_HTTPS_U1_P1.origin,
+    ],
+  ];
+
+  for (let tc of testcases) {
+    let description = tc.shift();
+    let expected = tc.shift();
+    let actual = LoginHelper.dedupeLogins(...tc);
+    info(`'${description}' actual:\n ${JSON.stringify(actual, null, 2)}`);
+    Assert.strictEqual(actual.length, expected.length, `Check: ${description}`);
+    for (let [i, login] of expected.entries()) {
+      Assert.strictEqual(actual[i], login, `Check index ${i}`);
+    }
+  }
+});
+
+add_task(async function test_dedupeLogins_preferredOriginMissing() {
+  let testcases = [
+    [
+      "resolveBy scheme + timePasswordChanged, missing preferredOrigin",
+      /preferredOrigin/,
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      undefined,
+      ["scheme", "timePasswordChanged"],
+    ],
+    [
+      "resolveBy timePasswordChanged + scheme, missing preferredOrigin",
+      /preferredOrigin/,
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      undefined,
+      ["timePasswordChanged", "scheme"],
+    ],
+    [
+      "resolveBy scheme + timePasswordChanged, empty preferredOrigin",
+      /preferredOrigin/,
+      [DOMAIN1_HTTPS_TO_HTTP_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      undefined,
+      ["scheme", "timePasswordChanged"],
+      "",
+    ],
+  ];
+
+  for (let tc of testcases) {
+    let description = tc.shift();
+    let expectedException = tc.shift();
+    Assert.throws(
+      () => {
+        LoginHelper.dedupeLogins(...tc);
+      },
+      expectedException,
+      `Check: ${description}`
+    );
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_disabled_hosts.js b/toolkit/components/passwordmgr/test/unit/test_disabled_hosts.js
new file mode 100644
index 0000000000..1d6e161149
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_disabled_hosts.js
@@ -0,0 +1,223 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests getLoginSavingEnabled, setLoginSavingEnabled, and getAllDisabledHosts.
+ */
+
+"use strict";
+
+// Tests
+
+/**
+ * Tests setLoginSavingEnabled and getAllDisabledHosts.
+ */
+add_task(function test_setLoginSavingEnabled_getAllDisabledHosts() {
+  // Add some disabled hosts, and verify that different schemes for the same
+  // domain are considered different hosts.
+  let origin1 = "http://disabled1.example.com";
+  let origin2 = "http://disabled2.example.com";
+  let origin3 = "https://disabled2.example.com";
+  Services.logins.setLoginSavingEnabled(origin1, false);
+  Services.logins.setLoginSavingEnabled(origin2, false);
+  Services.logins.setLoginSavingEnabled(origin3, false);
+
+  LoginTestUtils.assertDisabledHostsEqual(
+    Services.logins.getAllDisabledHosts(),
+    [origin1, origin2, origin3]
+  );
+
+  // Adding the same host twice should not result in an error.
+  Services.logins.setLoginSavingEnabled(origin2, false);
+  LoginTestUtils.assertDisabledHostsEqual(
+    Services.logins.getAllDisabledHosts(),
+    [origin1, origin2, origin3]
+  );
+
+  // Removing a disabled host should work.
+  Services.logins.setLoginSavingEnabled(origin2, true);
+  LoginTestUtils.assertDisabledHostsEqual(
+    Services.logins.getAllDisabledHosts(),
+    [origin1, origin3]
+  );
+
+  // Removing the last disabled host should work.
+  Services.logins.setLoginSavingEnabled(origin1, true);
+  Services.logins.setLoginSavingEnabled(origin3, true);
+  LoginTestUtils.assertDisabledHostsEqual(
+    Services.logins.getAllDisabledHosts(),
+    []
+  );
+});
+
+/**
+ * Tests setLoginSavingEnabled and getLoginSavingEnabled.
+ */
+add_task(function test_setLoginSavingEnabled_getLoginSavingEnabled() {
+  let origin1 = "http://disabled.example.com";
+  let origin2 = "https://disabled.example.com";
+
+  // Hosts should not be disabled by default.
+  Assert.ok(Services.logins.getLoginSavingEnabled(origin1));
+  Assert.ok(Services.logins.getLoginSavingEnabled(origin2));
+
+  // Test setting initial values.
+  Services.logins.setLoginSavingEnabled(origin1, false);
+  Services.logins.setLoginSavingEnabled(origin2, true);
+  Assert.ok(!Services.logins.getLoginSavingEnabled(origin1));
+  Assert.ok(Services.logins.getLoginSavingEnabled(origin2));
+
+  // Test changing values.
+  Services.logins.setLoginSavingEnabled(origin1, true);
+  Services.logins.setLoginSavingEnabled(origin2, false);
+  Assert.ok(Services.logins.getLoginSavingEnabled(origin1));
+  Assert.ok(!Services.logins.getLoginSavingEnabled(origin2));
+
+  // Clean up.
+  Services.logins.setLoginSavingEnabled(origin2, true);
+});
+
+/**
+ * Tests setLoginSavingEnabled with invalid NUL characters in the origin.
+ */
+add_task(function test_setLoginSavingEnabled_invalid_characters() {
+  let origin = "http://null\0X.example.com";
+  Assert.throws(
+    () => Services.logins.setLoginSavingEnabled(origin, false),
+    /Invalid origin/
+  );
+
+  // Verify that no data was stored by the previous call.
+  LoginTestUtils.assertDisabledHostsEqual(
+    Services.logins.getAllDisabledHosts(),
+    []
+  );
+});
+
+/**
+ * Tests different values of the "signon.rememberSignons" property.
+ */
+add_task(function test_rememberSignons() {
+  let origin1 = "http://example.com";
+  let origin2 = "http://localhost";
+
+  // The default value for the preference should be true.
+  Assert.ok(Services.prefs.getBoolPref("signon.rememberSignons"));
+
+  // Hosts should not be disabled by default.
+  Services.logins.setLoginSavingEnabled(origin1, false);
+  Assert.ok(!Services.logins.getLoginSavingEnabled(origin1));
+  Assert.ok(Services.logins.getLoginSavingEnabled(origin2));
+
+  // Disable storage of saved passwords globally.
+  Services.prefs.setBoolPref("signon.rememberSignons", false);
+  registerCleanupFunction(() =>
+    Services.prefs.clearUserPref("signon.rememberSignons")
+  );
+
+  // All hosts should now appear disabled.
+  Assert.ok(!Services.logins.getLoginSavingEnabled(origin1));
+  Assert.ok(!Services.logins.getLoginSavingEnabled(origin2));
+
+  // The list of disabled hosts should be unaltered.
+  LoginTestUtils.assertDisabledHostsEqual(
+    Services.logins.getAllDisabledHosts(),
+    [origin1]
+  );
+
+  // Changing values with the preference set should work.
+  Services.logins.setLoginSavingEnabled(origin1, true);
+  Services.logins.setLoginSavingEnabled(origin2, false);
+
+  // All hosts should still appear disabled.
+  Assert.ok(!Services.logins.getLoginSavingEnabled(origin1));
+  Assert.ok(!Services.logins.getLoginSavingEnabled(origin2));
+
+  // The list of disabled hosts should have been changed.
+  LoginTestUtils.assertDisabledHostsEqual(
+    Services.logins.getAllDisabledHosts(),
+    [origin2]
+  );
+
+  // Enable storage of saved passwords again.
+  Services.prefs.setBoolPref("signon.rememberSignons", true);
+
+  // Hosts should now appear enabled as requested.
+  Assert.ok(Services.logins.getLoginSavingEnabled(origin1));
+  Assert.ok(!Services.logins.getLoginSavingEnabled(origin2));
+
+  // Clean up.
+  Services.logins.setLoginSavingEnabled(origin2, true);
+  LoginTestUtils.assertDisabledHostsEqual(
+    Services.logins.getAllDisabledHosts(),
+    []
+  );
+});
+
+/**
+ * Tests storing disabled hosts with non-ASCII characters where IDN is supported.
+ */
+add_task(
+  async function test_storage_setLoginSavingEnabled_nonascii_IDN_is_supported() {
+    let origin = "http://大.net";
+    let encoding = "http://xn--pss.net";
+
+    // Test adding disabled host with nonascii URL (http://大.net).
+    Services.logins.setLoginSavingEnabled(origin, false);
+    await LoginTestUtils.reloadData();
+    Assert.equal(Services.logins.getLoginSavingEnabled(origin), false);
+    Assert.equal(Services.logins.getLoginSavingEnabled(encoding), false);
+    LoginTestUtils.assertDisabledHostsEqual(
+      Services.logins.getAllDisabledHosts(),
+      [origin]
+    );
+
+    LoginTestUtils.clearData();
+
+    // Test adding disabled host with IDN ("http://xn--pss.net").
+    Services.logins.setLoginSavingEnabled(encoding, false);
+    await LoginTestUtils.reloadData();
+    Assert.equal(Services.logins.getLoginSavingEnabled(origin), false);
+    Assert.equal(Services.logins.getLoginSavingEnabled(encoding), false);
+    LoginTestUtils.assertDisabledHostsEqual(
+      Services.logins.getAllDisabledHosts(),
+      [origin]
+    );
+
+    LoginTestUtils.clearData();
+  }
+);
+
+/**
+ * Tests storing disabled hosts with non-ASCII characters where IDN is not supported.
+ */
+add_task(
+  async function test_storage_setLoginSavingEnabled_nonascii_IDN_not_supported() {
+    let origin = "http://√.com";
+    let encoding = "http://xn--19g.com";
+
+    // Test adding disabled host with nonascii URL (http://√.com).
+    Services.logins.setLoginSavingEnabled(origin, false);
+    await LoginTestUtils.reloadData();
+    Assert.equal(Services.logins.getLoginSavingEnabled(origin), false);
+    Assert.equal(Services.logins.getLoginSavingEnabled(encoding), false);
+    LoginTestUtils.assertDisabledHostsEqual(
+      Services.logins.getAllDisabledHosts(),
+      [encoding]
+    );
+
+    LoginTestUtils.clearData();
+
+    // Test adding disabled host with IDN ("http://xn--19g.com").
+    Services.logins.setLoginSavingEnabled(encoding, false);
+    await LoginTestUtils.reloadData();
+    Assert.equal(Services.logins.getLoginSavingEnabled(origin), false);
+    Assert.equal(Services.logins.getLoginSavingEnabled(encoding), false);
+    LoginTestUtils.assertDisabledHostsEqual(
+      Services.logins.getAllDisabledHosts(),
+      [encoding]
+    );
+
+    LoginTestUtils.clearData();
+  }
+);
diff --git a/toolkit/components/passwordmgr/test/unit/test_displayOrigin.js b/toolkit/components/passwordmgr/test/unit/test_displayOrigin.js
new file mode 100644
index 0000000000..a42f066b3e
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_displayOrigin.js
@@ -0,0 +1,43 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Test nsILoginInfo.displayOrigin
+ */
+
+"use strict";
+
+add_task(function test_displayOrigin() {
+  // Trying to access `displayOrigin` for each login shouldn't throw.
+  for (let loginInfo of TestData.loginList()) {
+    let { displayOrigin } = loginInfo;
+    info(loginInfo.origin);
+    info(displayOrigin);
+    Assert.equal(typeof displayOrigin, "string", "Check type");
+    Assert.greater(displayOrigin.length, 0, "Check length");
+    if (loginInfo.origin.startsWith("file://")) {
+      // Fails to create the URL
+      Assert.ok(displayOrigin.startsWith(loginInfo.origin), "Contains origin");
+    } else {
+      Assert.ok(
+        displayOrigin.startsWith(loginInfo.origin.replace(/.+:\/\//, "")),
+        "Contains domain"
+      );
+    }
+    let matches;
+    if ((matches = loginInfo.origin.match(/:([0-9]+)$/))) {
+      Assert.ok(displayOrigin.includes(matches[1]), "Check port is included");
+    }
+    Assert.ok(!displayOrigin.includes("null"), "Doesn't contain `null`");
+    Assert.ok(
+      !displayOrigin.includes("undefined"),
+      "Doesn't contain `undefined`"
+    );
+    if (loginInfo.httpRealm !== null) {
+      Assert.ok(
+        displayOrigin.includes(loginInfo.httpRealm),
+        "Contains httpRealm"
+      );
+    }
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_doLoginsMatch.js b/toolkit/components/passwordmgr/test/unit/test_doLoginsMatch.js
new file mode 100644
index 0000000000..fb38f08cf7
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_doLoginsMatch.js
@@ -0,0 +1,57 @@
+/**
+ * Test LoginHelper.doLoginsMatch
+ */
+
+add_task(function test_formActionOrigin_ignoreSchemes() {
+  let httpActionLogin = TestData.formLogin();
+  let httpsActionLogin = TestData.formLogin({
+    formActionOrigin: "https://www.example.com",
+  });
+  let jsActionLogin = TestData.formLogin({
+    formActionOrigin: "javascript:",
+  });
+  let emptyActionLogin = TestData.formLogin({
+    formActionOrigin: "",
+  });
+
+  Assert.notEqual(
+    httpActionLogin.formActionOrigin,
+    httpsActionLogin.formActionOrigin,
+    "Ensure actions differ"
+  );
+
+  const TEST_CASES = [
+    [httpActionLogin, httpActionLogin, true],
+    [httpsActionLogin, httpsActionLogin, true],
+    [jsActionLogin, jsActionLogin, true],
+    [emptyActionLogin, emptyActionLogin, true],
+    // only differing by scheme:
+    [httpsActionLogin, httpActionLogin, true],
+    [httpActionLogin, httpsActionLogin, true],
+
+    // empty matches everything
+    [httpsActionLogin, emptyActionLogin, true],
+    [emptyActionLogin, httpsActionLogin, true],
+    [jsActionLogin, emptyActionLogin, true],
+    [emptyActionLogin, jsActionLogin, true],
+
+    // Begin false cases:
+    [httpsActionLogin, jsActionLogin, false],
+    [jsActionLogin, httpsActionLogin, false],
+    [httpActionLogin, jsActionLogin, false],
+    [jsActionLogin, httpActionLogin, false],
+  ];
+
+  for (let [login1, login2, expected] of TEST_CASES) {
+    Assert.strictEqual(
+      LoginHelper.doLoginsMatch(login1, login2, {
+        ignorePassword: false,
+        ignoreSchemes: true,
+      }),
+      expected,
+      `LoginHelper.doLoginsMatch:
+\t${JSON.stringify(login1)}
+\t${JSON.stringify(login2)}`
+    );
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_findRelatedRealms.js b/toolkit/components/passwordmgr/test/unit/test_findRelatedRealms.js
new file mode 100644
index 0000000000..b79a0ab4c4
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_findRelatedRealms.js
@@ -0,0 +1,156 @@
+/* Any copyright is dedicated to the Public Domain.
+http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const { LoginRelatedRealmsParent } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginRelatedRealms.sys.mjs"
+);
+const { RemoteSettings } = ChromeUtils.importESModule(
+  "resource://services-settings/remote-settings.sys.mjs"
+);
+
+const REMOTE_SETTINGS_COLLECTION = "websites-with-shared-credential-backends";
+
+add_task(async function test_related_domain_matching() {
+  const client = RemoteSettings(REMOTE_SETTINGS_COLLECTION);
+  const records = await client.get();
+  console.log(records);
+
+  // Assumes that the test collection is a 2D array with one subarray
+  let relatedRealms = records[0].relatedRealms;
+  relatedRealms = relatedRealms.flat();
+  Assert.ok(relatedRealms);
+
+  let LRR = new LoginRelatedRealmsParent();
+
+  // We should not return unrelated realms
+  let result = await LRR.findRelatedRealms("https://not-example.com");
+  equal(result.length, 0, "Check that there were no related realms found");
+
+  // We should not return unrelated realms given an unrelated subdomain
+  result = await LRR.findRelatedRealms("https://sub.not-example.com");
+  equal(result.length, 0, "Check that there were no related realms found");
+  // We should return the related realms collection
+  result = await LRR.findRelatedRealms("https://sub.example.com");
+  equal(
+    result.length,
+    relatedRealms.length,
+    "Ensure that three related realms were found"
+  );
+
+  // We should return the related realms collection minus the base domain that we searched with
+  result = await LRR.findRelatedRealms("https://example.co.uk");
+  equal(
+    result.length,
+    relatedRealms.length - 1,
+    "Ensure that two related realms were found"
+  );
+});
+
+add_task(async function test_newly_synced_collection() {
+  // Initialize LoginRelatedRealmsParent so the sync handler is enabled
+  let LRR = new LoginRelatedRealmsParent();
+  await LRR.getSharedCredentialsCollection();
+
+  const client = RemoteSettings(REMOTE_SETTINGS_COLLECTION);
+  let records = await client.get();
+  const record1 = {
+    id: records[0].id,
+    relatedRealms: records[0].relatedRealms,
+  };
+
+  // Assumes that the test collection is a 2D array with one subarray
+  let originalRelatedRealms = records[0].relatedRealms;
+  originalRelatedRealms = originalRelatedRealms.flat();
+  Assert.ok(originalRelatedRealms);
+
+  const updatedRelatedRealms = ["completely-different.com", "example.com"];
+  const record2 = {
+    id: "some-other-ID",
+    relatedRealms: [updatedRelatedRealms],
+  };
+  const payload = {
+    current: [record2],
+    created: [record2],
+    updated: [],
+    deleted: [record1],
+  };
+  await RemoteSettings(REMOTE_SETTINGS_COLLECTION).emit("sync", {
+    data: payload,
+  });
+
+  let [{ id, relatedRealms }] = await LRR.getSharedCredentialsCollection();
+  equal(id, record2.id, "internal collection ID should be updated");
+  equal(
+    relatedRealms,
+    record2.relatedRealms,
+    "internal collection related realms should be updated"
+  );
+
+  // We should return only one result, and that result should be example.com
+  // NOT other-example.com or example.co.uk
+  let result = await LRR.findRelatedRealms("https://completely-different.com");
+  equal(
+    result.length,
+    updatedRelatedRealms.length - 1,
+    "Check that there is only one related realm found"
+  );
+  equal(
+    result[0],
+    "example.com",
+    "Ensure that the updated collection should only match example.com"
+  );
+});
+
+add_task(async function test_no_related_domains() {
+  await LoginTestUtils.remoteSettings.cleanWebsitesWithSharedCredentials();
+
+  const client = RemoteSettings(REMOTE_SETTINGS_COLLECTION);
+  let records = await client.get();
+
+  equal(records.length, 0, "Check that there are no related realms");
+
+  let LRR = new LoginRelatedRealmsParent();
+
+  Assert.ok(LRR.findRelatedRealms, "Ensure findRelatedRealms exists");
+
+  let result = await LRR.findRelatedRealms("https://example.com");
+  equal(result.length, 0, "Assert that there were no related realms found");
+});
+
+add_task(async function test_unrelated_subdomains() {
+  await LoginTestUtils.remoteSettings.cleanWebsitesWithSharedCredentials();
+  let testCollection = [
+    ["slpl.bibliocommons.com", "slpl.overdrive.com"],
+    ["springfield.overdrive.com", "coolcat.org"],
+  ];
+  await LoginTestUtils.remoteSettings.setupWebsitesWithSharedCredentials(
+    testCollection
+  );
+
+  let LRR = new LoginRelatedRealmsParent();
+  let result = await LRR.findRelatedRealms("https://evil.overdrive.com");
+  equal(result.length, 0, "Assert that there were no related realms found");
+
+  result = await LRR.findRelatedRealms("https://abc.slpl.bibliocommons.com");
+  equal(result.length, 2, "Assert that two related realms were found");
+  equal(result[0], testCollection[0][0]);
+  equal(result[1], testCollection[0][1]);
+
+  result = await LRR.findRelatedRealms("https://slpl.overdrive.com");
+  console.log("what is result: " + result);
+  equal(result.length, 1, "Assert that one related realm was found");
+  for (let item of result) {
+    notEqual(
+      item,
+      "coolcat.org",
+      "coolcat.org is not related to slpl.overdrive.com"
+    );
+    notEqual(
+      item,
+      "springfield.overdrive.com",
+      "springfield.overdrive.com is not related to slpl.overdrive.com"
+    );
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_getFormFields.js b/toolkit/components/passwordmgr/test/unit/test_getFormFields.js
new file mode 100644
index 0000000000..a04b497181
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_getFormFields.js
@@ -0,0 +1,572 @@
+/**
+ * Test for LoginFormState._getFormFields.
+ */
+
+"use strict";
+
+const { LoginFormFactory } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginFormFactory.sys.mjs"
+);
+
+const { LoginManagerChild } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerChild.sys.mjs"
+);
+
+const TESTENVIRONMENTS = {
+  filledPW1WithGeneratedPassword: {
+    generatedPWFieldSelectors: ["#pw1"],
+  },
+};
+
+const TESTCASES = [
+  {
+    description: "1 password field outside of a <form>",
+    document: `<input id="pw1" type=password>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description: "1 text field outside of a <form> without a password field",
+    document: `<input id="un1">`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: null,
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    // there is no password field to fill, so no sense testing with gen. passwords
+    extraTestEnvironments: [],
+    extraTestPreferences: [],
+  },
+  {
+    description: "1 username & password field outside of a <form>",
+    document: `<input id="un1">
+      <input id="pw1" type=password>`,
+    returnedFieldIDs: {
+      usernameField: "un1",
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    beforeGetFunction(doc, formLike) {
+      // Access the formLike.elements lazy getter to have it cached.
+      Assert.equal(
+        formLike.elements.length,
+        2,
+        "Check initial elements length"
+      );
+      doc.getElementById("un1").remove();
+    },
+    description: "1 username & password field outside of a <form>, un1 removed",
+    document: `<input id="un1">
+      <input id="pw1" type=password>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description: "1 username & password field in a <form>",
+    document: `<form>
+      <input id="un1">
+      <input id="pw1" type=password>
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: "un1",
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description: "5 empty password fields outside of a <form>",
+    document: `<input id="pw1" type=password>
+      <input id="pw2" type=password>
+      <input id="pw3" type=password>
+      <input id="pw4" type=password>
+      <input id="pw5" type=password>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description: "6 empty password fields outside of a <form>",
+    document: `<input id="pw1" type=password>
+      <input id="pw2" type=password>
+      <input id="pw3" type=password>
+      <input id="pw4" type=password>
+      <input id="pw5" type=password>
+      <input id="pw6" type=password>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: null,
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "4 password fields outside of a <form> (1 empty, 3 full) with skipEmpty",
+    document: `<input id="pw1" type=password>
+      <input id="pw2" type=password value="pass2">
+      <input id="pw3" type=password value="pass3">
+      <input id="pw4" type=password value="pass4">`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: null,
+      oldPasswordField: null,
+    },
+    skipEmptyFields: true,
+    // This test assumes that pw1 has not been filled, so don't test prefilling it
+    extraTestEnvironments: [],
+    extraTestPreferences: [],
+  },
+  {
+    description: "Form with 1 password field",
+    document: `<form><input id="pw1" type=password></form>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description: "Form with 2 password fields",
+    document: `<form><input id="pw1" type=password><input id='pw2' type=password></form>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description: "1 password field in a form, 1 outside (not processed)",
+    document: `<form><input id="pw1" type=password></form><input id="pw2" type=password>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "1 password field in a form, 1 text field outside (not processed)",
+    document: `<form><input id="pw1" type=password></form><input>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "1 text field in a form, 1 password field outside (not processed)",
+    document: `<form><input></form><input id="pw1" type=password>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: null,
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "2 password fields outside of a <form> with 1 linked via @form",
+    document: `<input id="pw1" type=password><input id="pw2" type=password form='form1'>
+      <form id="form1"></form>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "2 password fields outside of a <form> with 1 linked via @form + skipEmpty",
+    document: `<input id="pw1" type=password><input id="pw2" type=password form="form1">
+      <form id="form1"></form>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: null,
+      oldPasswordField: null,
+    },
+    skipEmptyFields: true,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "2 password fields outside of a <form> with 1 linked via @form + skipEmpty with 1 empty",
+    document: `<input id="pw1" type=password value="pass1"><input id="pw2" type=password form="form1">
+      <form id="form1"></form>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: true,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "3 password fields, 2nd and 3rd are filled with generated passwords",
+    document: `<input id="pw1" type=password>
+      <input id="pw2" type=password value="pass2">
+      <input id="pw3" type=password value="pass3">`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: "pw2",
+      confirmPasswordField: "pw3",
+      oldPasswordField: "pw1",
+    },
+    skipEmptyFields: undefined,
+    generatedPWFieldSelectors: ["#pw2", "#pw3"],
+    // this test doesn't make sense to run with different filled generated password values
+    extraTestEnvironments: [],
+    extraTestPreferences: [],
+  },
+  // begin of getusername heuristic tests
+  {
+    description: "multiple non-username like input fields in a <form>",
+    document: `<form>
+      <input id="un1">
+      <input id="un2">
+      <input id="un3">
+      <input id="pw1" type=password>
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: "un3",
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "1 username input and multiple non-username like input in a <form>",
+    document: `<form>
+      <input id="un1">
+      <input id="un2" autocomplete="username">
+      <input id="un3">
+      <input id="pw1" type=password>
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: "un2",
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "1 email input and multiple non-username like input in a <form>",
+    document: `<form>
+      <input id="un1">
+      <input id="un2" autocomplete="email">
+      <input id="un3">
+      <input id="pw1" type=password>
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: "un2",
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "1 username & 1 email field, the email field is more close to the password",
+    document: `<form>
+      <input id="un1" autocomplete="username">
+      <input id="un2" autocomplete="email">
+      <input id="pw1" type=password>
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: "un1",
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description:
+      "1 username and 1 email field, the username field is more close to the password",
+    document: `<form>
+      <input id="un1" autocomplete="email">
+      <input id="un2" autocomplete="username">
+      <input id="pw1" type=password>
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: "un2",
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description: "2 username fields in a <form>",
+    document: `<form>
+      <input id="un1" autocomplete="username">
+      <input id="un2" autocomplete="username">
+      <input id="un3">
+      <input id="pw1" type=password>
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: "un2",
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description: "2 email fields in a <form>",
+    document: `<form>
+      <input id="un1" autocomplete="email">
+      <input id="un2" autocomplete="email">
+      <input id="un3">
+      <input id="pw1" type=password>
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: "un1",
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  {
+    description: "the password field precedes the username field",
+    document: `<form>
+      <input id="un1">
+      <input id="pw1" type=password>
+      <input id="un2" autocomplete="username">
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: "un1",
+      newPasswordField: "pw1",
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [TESTENVIRONMENTS.filledPW1WithGeneratedPassword],
+    extraTestPreferences: [],
+  },
+  // end of getusername heuristic tests
+  {
+    description: "1 username field in a <form>",
+    document: `<form>
+      <input id="un1" autocomplete="username">
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: "un1",
+      newPasswordField: null,
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [],
+    extraTestPreferences: [],
+  },
+  {
+    description: "1 input field in a <form>",
+    document: `<form>
+      <input id="un1"">
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: null,
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [],
+    extraTestPreferences: [],
+  },
+  {
+    description: "1 username field in a <form> with usernameOnlyForm pref off",
+    document: `<form>
+      <input id="un1" autocomplete="username">
+      </form>`,
+    returnedFieldIDs: {
+      usernameField: null,
+      newPasswordField: null,
+      oldPasswordField: null,
+    },
+    skipEmptyFields: undefined,
+    extraTestEnvironments: [],
+    extraTestPreferences: [["signon.usernameOnlyForm.enabled", false]],
+  },
+];
+
+const TEST_ENVIRONMENT_CASES = TESTCASES.flatMap(tc => {
+  let arr = [tc];
+  // also run this test case with this different state
+  for (let env of tc.extraTestEnvironments) {
+    arr.push({
+      ...tc,
+      ...env,
+    });
+  }
+  return arr;
+});
+
+function _setPrefs() {
+  Services.prefs.setBoolPref("signon.usernameOnlyForm.enabled", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.usernameOnlyForm.enabled");
+  });
+}
+
+_setPrefs();
+
+for (let tc of TEST_ENVIRONMENT_CASES) {
+  info("Sanity checking the testcase: " + tc.description);
+
+  (function () {
+    let testcase = tc;
+    add_task(async function () {
+      info("Starting testcase: " + testcase.description);
+
+      for (let pref of testcase.extraTestPreferences) {
+        Services.prefs.setBoolPref(pref[0], pref[1]);
+      }
+
+      info("Document string: " + testcase.document);
+      let document = MockDocument.createTestDocument(
+        "http://localhost:8080/test/",
+        testcase.document
+      );
+
+      let input = document.querySelector("input");
+      MockDocument.mockOwnerDocumentProperty(
+        input,
+        document,
+        "http://localhost:8080/test/"
+      );
+
+      let formLike = LoginFormFactory.createFromField(input);
+
+      if (testcase.beforeGetFunction) {
+        await testcase.beforeGetFunction(document, formLike);
+      }
+
+      let lmc = new LoginManagerChild();
+      let loginFormState = lmc.stateForDocument(formLike.ownerDocument);
+      loginFormState.generatedPasswordFields = _generateDocStateFromTestCase(
+        testcase,
+        document
+      );
+
+      let actual = loginFormState._getFormFields(
+        formLike,
+        testcase.skipEmptyFields,
+        new Set()
+      );
+
+      [
+        "usernameField",
+        "newPasswordField",
+        "oldPasswordField",
+        "confirmPasswordField",
+      ].forEach(fieldName => {
+        Assert.ok(
+          fieldName in actual,
+          "_getFormFields return value includes " + fieldName
+        );
+      });
+      for (let key of Object.keys(testcase.returnedFieldIDs)) {
+        let expectedID = testcase.returnedFieldIDs[key];
+        if (expectedID === null) {
+          Assert.strictEqual(
+            actual[key],
+            expectedID,
+            "Check returned field " + key + " is null"
+          );
+        } else {
+          Assert.strictEqual(
+            actual[key].id,
+            expectedID,
+            "Check returned field " + key + " ID"
+          );
+        }
+      }
+
+      for (let pref of tc.extraTestPreferences) {
+        Services.prefs.clearUserPref(pref[0]);
+      }
+    });
+  })();
+}
+
+function _generateDocStateFromTestCase(stateProperties, document) {
+  // prepopulate the document form state LMC holds with
+  // any generated password fields defined in this testcase
+  let generatedPasswordFields = new Set();
+  info(
+    "stateProperties has generatedPWFieldSelectors: " +
+      stateProperties.generatedPWFieldSelectors?.join(", ")
+  );
+
+  if (stateProperties.generatedPWFieldSelectors?.length) {
+    stateProperties.generatedPWFieldSelectors.forEach(sel => {
+      let field = document.querySelector(sel);
+      if (field) {
+        generatedPasswordFields.add(field);
+      } else {
+        info(`No password field: ${sel} found in this document`);
+      }
+    });
+  }
+  return generatedPasswordFields;
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_getPasswordFields.js b/toolkit/components/passwordmgr/test/unit/test_getPasswordFields.js
new file mode 100644
index 0000000000..eee38c30d8
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_getPasswordFields.js
@@ -0,0 +1,308 @@
+/**
+ * Test for LoginFormState._getPasswordFields using LoginFormFactory.
+ */
+
+/* globals todo_check_eq */
+"use strict";
+
+const { LoginFormFactory } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginFormFactory.sys.mjs"
+);
+const { LoginFormState } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerChild.sys.mjs"
+);
+const TESTCASES = [
+  {
+    description: "Empty document",
+    document: ``,
+    returnedFieldIDsByFormLike: [],
+    minPasswordLength: undefined,
+  },
+  {
+    description: "Non-password input with no <form> present",
+    document: `<input>`,
+    // Only the IDs of password fields should be in this array
+    returnedFieldIDsByFormLike: [[]],
+    minPasswordLength: undefined,
+  },
+  {
+    description: "1 password field outside of a <form>",
+    document: `<input id="pw1" type=password>`,
+    returnedFieldIDsByFormLike: [["pw1"]],
+    minPasswordLength: undefined,
+  },
+  {
+    description: "5 empty password fields outside of a <form>",
+    document: `<input id="pw1" type=password>
+      <input id="pw2" type=password>
+      <input id="pw3" type=password>
+      <input id="pw4" type=password>
+      <input id="pw5" type=password>`,
+    returnedFieldIDsByFormLike: [["pw1", "pw2", "pw3", "pw4", "pw5"]],
+    minPasswordLength: undefined,
+  },
+  {
+    description: "6 empty password fields outside of a <form>",
+    document: `<input id="pw1" type=password>
+      <input id="pw2" type=password>
+      <input id="pw3" type=password>
+      <input id="pw4" type=password>
+      <input id="pw5" type=password>
+      <input id="pw6" type=password>`,
+    returnedFieldIDsByFormLike: [[]],
+    minPasswordLength: undefined,
+  },
+  {
+    description:
+      "4 password fields outside of a <form> (1 empty, 3 full) with minPasswordLength=2",
+    document: `<input id="pw1" type=password>
+      <input id="pw2" type=password value="pass2">
+      <input id="pw3" type=password value="pass3">
+      <input id="pw4" type=password value="pass4">`,
+    returnedFieldIDsByFormLike: [["pw2", "pw3", "pw4"]],
+    minPasswordLength: 2,
+  },
+  {
+    description: "Form with 1 password field",
+    document: `<form><input id="pw1" type=password></form>`,
+    returnedFieldIDsByFormLike: [["pw1"]],
+    minPasswordLength: undefined,
+  },
+  {
+    description: "Form with 2 password fields",
+    document: `<form><input id="pw1" type=password><input id='pw2' type=password></form>`,
+    returnedFieldIDsByFormLike: [["pw1", "pw2"]],
+    minPasswordLength: undefined,
+  },
+  {
+    description: "1 password field in a form, 1 outside",
+    document: `<form><input id="pw1" type=password></form><input id="pw2" type=password>`,
+    returnedFieldIDsByFormLike: [["pw1"], ["pw2"]],
+    minPasswordLength: undefined,
+  },
+  {
+    description:
+      "2 password fields outside of a <form> with 1 linked via @form",
+    document: `<input id="pw1" type=password><input id="pw2" type=password form='form1'>
+      <form id="form1"></form>`,
+    returnedFieldIDsByFormLike: [["pw1"], ["pw2"]],
+    minPasswordLength: undefined,
+  },
+  {
+    description:
+      "2 password fields outside of a <form> with 1 linked via @form + minPasswordLength",
+    document: `<input id="pw1" type=password><input id="pw2" type=password form="form1">
+      <form id="form1"></form>`,
+    returnedFieldIDsByFormLike: [[], []],
+    minPasswordLength: 2,
+  },
+  {
+    description: "minPasswordLength should also skip white-space only fields",
+    /* eslint-disable no-tabs */
+    document: `<input id="pw-space" type=password value=" ">
+               <input id="pw-tab" type=password value="	">
+               <input id="pw-newline" type=password form="form1" value="
+                                                                        ">
+      <form id="form1"></form>`,
+    /* eslint-enable no-tabs */
+    returnedFieldIDsByFormLike: [[], []],
+    minPasswordLength: 2,
+  },
+  {
+    description: "minPasswordLength should skip too-short field values",
+    document: `<form>
+               <input id="pw-empty" type=password>
+               <input id="pw-tooshort" type=password value="p">
+               <input id="pw" type=password value="pz">
+               </form>`,
+    returnedFieldIDsByFormLike: [["pw"]],
+    minPasswordLength: 2,
+  },
+  {
+    description: "minPasswordLength should allow matching-length field values",
+    document: `<form>
+               <input id="pw-empty" type=password>
+               <input id="pw-matchlen" type=password value="pz">
+               <input id="pw" type=password value="pazz">
+               </form>`,
+    returnedFieldIDsByFormLike: [["pw-matchlen", "pw"]],
+    minPasswordLength: 2,
+  },
+  {
+    description:
+      "2 password fields outside of a <form> with 1 linked via @form + minPasswordLength with 1 empty",
+    document: `<input id="pw1" type=password value=" pass1 "><input id="pw2" type=password form="form1">
+      <form id="form1"></form>`,
+    returnedFieldIDsByFormLike: [["pw1"], []],
+    minPasswordLength: 2,
+    fieldOverrideRecipe: {
+      // Ensure a recipe without `notPasswordSelector` doesn't cause a problem.
+      hosts: ["localhost:8080"],
+    },
+  },
+  {
+    description:
+      "3 password fields outside of a <form> with 1 linked via @form + minPasswordLength",
+    document: `<input id="pw1" type=password value="pass1"><input id="pw2" type=password form="form1" value="pass2"><input id="pw3" type=password value="pass3">
+      <form id="form1"><input id="pw4" type=password></form>`,
+    returnedFieldIDsByFormLike: [["pw3"], ["pw2"]],
+    minPasswordLength: 2,
+    fieldOverrideRecipe: {
+      hosts: ["localhost:8080"],
+      notPasswordSelector: "#pw1",
+    },
+  },
+  {
+    beforeGetFunction(doc) {
+      doc.getElementById("pw1").remove();
+    },
+    description:
+      "1 password field outside of a <form> which gets removed/disconnected",
+    document: `<input id="pw1" type=password>`,
+    returnedFieldIDsByFormLike: [[]],
+    minPasswordLength: undefined,
+  },
+];
+
+for (let tc of TESTCASES) {
+  info("Sanity checking the testcase: " + tc.description);
+
+  (function () {
+    let testcase = tc;
+    add_task(async function () {
+      info("Starting testcase: " + testcase.description);
+      let document = MockDocument.createTestDocument(
+        "http://localhost:8080/test/",
+        testcase.document
+      );
+
+      let mapRootElementToFormLike = new Map();
+      for (let input of document.querySelectorAll("input")) {
+        let formLike = LoginFormFactory.createFromField(input);
+        let existingFormLike = mapRootElementToFormLike.get(
+          formLike.rootElement
+        );
+        if (!existingFormLike) {
+          mapRootElementToFormLike.set(formLike.rootElement, formLike);
+          continue;
+        }
+
+        // If the formLike is already present, ensure that the properties are the same.
+        info(
+          "Checking if the new FormLike for the same root has the same properties"
+        );
+        formLikeEqual(formLike, existingFormLike);
+      }
+
+      if (testcase.beforeGetFunction) {
+        await testcase.beforeGetFunction(document);
+      }
+
+      Assert.strictEqual(
+        mapRootElementToFormLike.size,
+        testcase.returnedFieldIDsByFormLike.length,
+        "Check the correct number of different formLikes were returned"
+      );
+
+      let formLikeIndex = -1;
+      for (let formLikeFromInput of mapRootElementToFormLike.values()) {
+        formLikeIndex++;
+        let pwFields = LoginFormState._getPasswordFields(formLikeFromInput, {
+          fieldOverrideRecipe: testcase.fieldOverrideRecipe,
+          minPasswordLength: testcase.minPasswordLength,
+        });
+
+        if (
+          ChromeUtils.getClassName(formLikeFromInput.rootElement) ===
+          "HTMLFormElement"
+        ) {
+          let formLikeFromForm = LoginFormFactory.createFromForm(
+            formLikeFromInput.rootElement
+          );
+          info(
+            "Checking that the FormLike created for the <form> matches" +
+              " the one from a password field"
+          );
+          formLikeEqual(formLikeFromInput, formLikeFromForm);
+        }
+
+        if (testcase.returnedFieldIDsByFormLike[formLikeIndex].length === 0) {
+          Assert.strictEqual(
+            pwFields,
+            null,
+            "If no password fields were found null should be returned"
+          );
+        } else {
+          Assert.strictEqual(
+            pwFields.length,
+            testcase.returnedFieldIDsByFormLike[formLikeIndex].length,
+            "Check the # of password fields for formLike #" + formLikeIndex
+          );
+        }
+
+        for (
+          let i = 0;
+          i < testcase.returnedFieldIDsByFormLike[formLikeIndex].length;
+          i++
+        ) {
+          let expectedID =
+            testcase.returnedFieldIDsByFormLike[formLikeIndex][i];
+          Assert.strictEqual(
+            pwFields[i].element.id,
+            expectedID,
+            "Check password field " + i + " ID"
+          );
+        }
+      }
+    });
+  })();
+}
+
+const EMOJI_TESTCASES = [
+  {
+    description:
+      "Single characters composed of 2 code units should ideally fail minPasswordLength of 2",
+    document: `<form>
+               <input id="pw" type=password value="💩">
+               </form>`,
+    returnedFieldIDsByFormLike: [["pw"]],
+    minPasswordLength: 2,
+  },
+  {
+    description:
+      "Single characters composed of multiple code units should ideally fail minPasswordLength of 2",
+    document: `<form>
+               <input id="pw" type=password value="👪">
+               </form>`,
+    minPasswordLength: 2,
+  },
+];
+
+// Note: Bug 780449 tracks our handling of emoji and multi-code-point characters in password fields
+// and the .length we should expect when a password value includes them
+for (let tc of EMOJI_TESTCASES) {
+  info("Sanity checking the testcase: " + tc.description);
+
+  (function () {
+    let testcase = tc;
+    add_task(async function () {
+      info("Starting testcase: " + testcase.description);
+      let document = MockDocument.createTestDocument(
+        "http://localhost:8080/test/",
+        testcase.document
+      );
+      let input = document.querySelector("input[type='password']");
+      Assert.ok(input, "Found the password field");
+      let formLike = LoginFormFactory.createFromField(input);
+      let pwFields = LoginFormState._getPasswordFields(formLike, {
+        minPasswordLength: testcase.minPasswordLength,
+      });
+      info("Got password fields: " + pwFields.length);
+      todo_check_eq(
+        pwFields.length,
+        0,
+        "Check a single-character (emoji) password is excluded from the password fields collection"
+      );
+    });
+  })();
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_getPasswordOrigin.js b/toolkit/components/passwordmgr/test/unit/test_getPasswordOrigin.js
new file mode 100644
index 0000000000..5ee8440525
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_getPasswordOrigin.js
@@ -0,0 +1,35 @@
+/**
+ * Test for LoginHelper.getLoginOrigin
+ */
+
+"use strict";
+
+const TESTCASES = [
+  ["javascript:void(0);", null],
+  ["javascript:void(0);", "javascript:", true],
+  ["chrome://MyAccount", "chrome://myaccount"],
+  ["data:text/html,example", null],
+  [
+    "http://username:password@example.com:80/foo?bar=baz#fragment",
+    "http://example.com",
+    true,
+  ],
+  ["http://127.0.0.1:80/foo", "http://127.0.0.1"],
+  ["http://[::1]:80/foo", "http://[::1]"],
+  ["http://example.com:8080/foo", "http://example.com:8080"],
+  ["http://127.0.0.1:8080/foo", "http://127.0.0.1:8080", true],
+  ["http://[::1]:8080/foo", "http://[::1]:8080"],
+  ["https://example.com:443/foo", "https://example.com"],
+  ["https://[::1]:443/foo", "https://[::1]"],
+  ["https://[::1]:8443/foo", "https://[::1]:8443"],
+  ["ftp://username:password@[::1]:2121/foo", "ftp://[::1]:2121"],
+  [
+    "moz-proxy://username:password@123.123.123.123:12345/foo",
+    "moz-proxy://123.123.123.123:12345",
+  ],
+];
+
+for (let [input, expected, allowJS] of TESTCASES) {
+  let actual = LoginHelper.getLoginOrigin(input, allowJS);
+  Assert.strictEqual(actual, expected, "Checking: " + input);
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_getUserNameAndPasswordFields.js b/toolkit/components/passwordmgr/test/unit/test_getUserNameAndPasswordFields.js
new file mode 100644
index 0000000000..2e845bef5d
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_getUserNameAndPasswordFields.js
@@ -0,0 +1,187 @@
+/**
+ * Test for LoginFormState.getUserNameAndPasswordFields
+ */
+
+"use strict";
+
+const { LoginManagerChild } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerChild.sys.mjs"
+);
+const TESTCASES = [
+  {
+    description: "1 password field outside of a <form>",
+    document: `<input id="pw1" type=password>`,
+    returnedFieldIDs: [null, "pw1", null],
+  },
+  {
+    description: "1 text field in a <form> without a password field",
+    document: `<form>
+      <input id="un1">
+      </form>`,
+    returnedFieldIDs: [null, null, null],
+  },
+  {
+    description: "1 text field outside of a <form> without a password field",
+    document: `<input id="un1">`,
+    returnedFieldIDs: [null, null, null],
+  },
+  {
+    description: "1 username & password field outside of a <form>",
+    document: `<input id="un1">
+      <input id="pw1" type=password>`,
+    returnedFieldIDs: ["un1", "pw1", null],
+  },
+  {
+    description: "1 username & password field in a <form>",
+    document: `<form>
+      <input id="un1">
+      <input id="pw1" type=password>
+      </form>`,
+    returnedFieldIDs: ["un1", "pw1", null],
+  },
+  {
+    description: "5 empty password fields outside of a <form>",
+    document: `<input id="pw1" type=password>
+      <input id="pw2" type=password>
+      <input id="pw3" type=password>
+      <input id="pw4" type=password>
+      <input id="pw5" type=password>`,
+    returnedFieldIDs: [null, "pw1", null],
+  },
+  {
+    description: "6 empty password fields outside of a <form>",
+    document: `<input id="pw1" type=password>
+      <input id="pw2" type=password>
+      <input id="pw3" type=password>
+      <input id="pw4" type=password>
+      <input id="pw5" type=password>
+      <input id="pw6" type=password>`,
+    returnedFieldIDs: [null, null, null],
+  },
+  {
+    description: "Form with 1 password field",
+    document: `<form><input id="pw1" type=password></form>`,
+    returnedFieldIDs: [null, "pw1", null],
+  },
+  {
+    description: "Form with 2 password fields",
+    document: `<form><input id="pw1" type=password><input id='pw2' type=password></form>`,
+    returnedFieldIDs: [null, "pw1", null],
+  },
+  {
+    description: "1 password field in a form, 1 outside (not processed)",
+    document: `<form><input id="pw1" type=password></form><input id="pw2" type=password>`,
+    returnedFieldIDs: [null, "pw1", null],
+  },
+  {
+    description:
+      "1 password field in a form, 1 text field outside (not processed)",
+    document: `<form><input id="pw1" type=password></form><input>`,
+    returnedFieldIDs: [null, "pw1", null],
+  },
+  {
+    description:
+      "1 text field in a form, 1 password field outside (not processed)",
+    document: `<form><input></form><input id="pw1" type=password>`,
+    returnedFieldIDs: [null, null, null],
+  },
+  {
+    description:
+      "2 password fields outside of a <form> with 1 linked via @form",
+    document: `<input id="pw1" type=password><input id="pw2" type=password form='form1'>
+      <form id="form1"></form>`,
+    returnedFieldIDs: [null, "pw1", null],
+  },
+  {
+    description: "1 username field in a <form>",
+    document: `<form>
+      <input id="un1" autocomplete=username>
+      </form>`,
+    returnedFieldIDs: ["un1", null, null],
+  },
+  {
+    description: "1 username field outside of a <form>",
+    document: `<input id="un1" autocomplete=username>`,
+    returnedFieldIDs: [null, null, null],
+  },
+  {
+    description: "username with type=user",
+    document: `<form><input id="un1" type="user"><input id="pwd" type="password"></form>`,
+    returnedFieldIDs: ["un1", "pwd", null],
+  },
+  {
+    description: "username with type=username",
+    document: `<form><input id="un1" type="username"><input id="pwd" type="password"></form>`,
+    returnedFieldIDs: ["un1", "pwd", null],
+  },
+];
+
+function _setPrefs() {
+  Services.prefs.setBoolPref("signon.usernameOnlyForm.enabled", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.usernameOnlyForm.enabled");
+  });
+}
+
+_setPrefs();
+
+for (let tc of TESTCASES) {
+  info("Sanity checking the testcase: " + tc.description);
+
+  (function () {
+    let testcase = tc;
+    add_task(async function () {
+      info("Starting testcase: " + testcase.description);
+      let document = MockDocument.createTestDocument(
+        "http://localhost:8080/test/",
+        testcase.document
+      );
+
+      let input = document.querySelector("input");
+      MockDocument.mockOwnerDocumentProperty(
+        input,
+        document,
+        "http://localhost:8080/test/"
+      );
+      MockDocument.mockNodePrincipalProperty(
+        input,
+        "http://localhost:8080/test/"
+      );
+
+      // Additional mock to cache recipes
+      let win = {};
+      Object.defineProperty(document, "defaultView", {
+        value: win,
+      });
+      let formOrigin = LoginHelper.getLoginOrigin(document.documentURI);
+      LoginRecipesContent.cacheRecipes(formOrigin, win, new Set());
+
+      const loginManagerChild = new LoginManagerChild();
+      const docState = loginManagerChild.stateForDocument(document);
+      let actual = docState.getUserNameAndPasswordFields(input);
+
+      Assert.strictEqual(
+        testcase.returnedFieldIDs.length,
+        3,
+        "getUserNameAndPasswordFields returns 3 elements"
+      );
+
+      for (let i = 0; i < testcase.returnedFieldIDs.length; i++) {
+        let expectedID = testcase.returnedFieldIDs[i];
+        if (expectedID === null) {
+          Assert.strictEqual(
+            actual[i],
+            expectedID,
+            "Check returned field " + i + " is null"
+          );
+        } else {
+          Assert.strictEqual(
+            actual[i].id,
+            expectedID,
+            "Check returned field " + i + " ID"
+          );
+        }
+      }
+    });
+  })();
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_getUsernameFieldFromUsernameOnlyForm.js b/toolkit/components/passwordmgr/test/unit/test_getUsernameFieldFromUsernameOnlyForm.js
new file mode 100644
index 0000000000..1af2bb889c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_getUsernameFieldFromUsernameOnlyForm.js
@@ -0,0 +1,179 @@
+/**
+ * Test for LoginFormState.getUsernameFieldFromUsernameOnlyForm
+ */
+
+"use strict";
+
+const { LoginManagerChild } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManagerChild.sys.mjs"
+);
+
+// expectation[0] tests cases when a form doesn't have a sign-in keyword.
+// expectation[1] tests cases when a form has a sign-in keyword.
+const TESTCASES = [
+  {
+    description: "1 text input field",
+    document: `<form>
+      <input id="un1" type="text">
+      </form>`,
+    expectations: [false, true],
+  },
+  {
+    description: "1 text input field & 1 hidden input fields",
+    document: `<form>
+      <input id="un1" type="text">
+      <input id="un2" type="hidden">
+      </form>`,
+    expectations: [false, true],
+  },
+  {
+    description: "1 username field",
+    document: `<form>
+      <input id="un1" autocomplete="username">
+      </form>`,
+    expectations: [true, true],
+  },
+  {
+    description: "1 username field & 1 hidden input fields",
+    document: `<form>
+      <input id="un1" autocomplete="username">
+      <input id="un2" type="hidden">
+      </form>`,
+    expectations: [true, true],
+  },
+  {
+    description: "1 username field, 1 hidden input field, & 1 password field",
+    document: `<form>
+      <input id="un1" autocomplete="username">
+      <input id="un2" type="hidden">
+      <input id="pw1" type=password>
+      </form>`,
+    expectations: [false, false],
+  },
+  {
+    description: "1 password field",
+    document: `<form>
+      <input id="pw1" type=password>
+      </form>`,
+    expectations: [false, false],
+  },
+  {
+    description: "1 username & password field",
+    document: `<form>
+      <input id="un1" autocomplete="username">
+      <input id="pw1" type=password>
+      </form>`,
+    expectations: [false, false],
+  },
+  {
+    description: "1 username & text field",
+    document: `<form>
+      <input id="un1" autocomplete="username">
+      <input id="un2" type="text">
+      </form>`,
+    expectations: [false, false],
+  },
+  {
+    description: "2 text input fields",
+    document: `<form>
+      <input id="un1" type="text">
+      <input id="un2" type="text">
+      </form>`,
+    expectations: [false, false],
+  },
+  {
+    description: "2 username fields",
+    document: `<form>
+      <input id="un1" autocomplete="username">
+      <input id="un2" autocomplete="username">
+      </form>`,
+    expectations: [false, false],
+  },
+  {
+    description: "1 username field with search keyword",
+    document: `<form>
+      <input id="un1" autocomplete="username" placeholder="search by username">
+      </form>`,
+    expectations: [false, false],
+  },
+  {
+    description: "1 text input field with code keyword",
+    document: `<form>
+      <input id="un1" type="text" placeholder="enter your 6-digit code">
+      </form>`,
+    expectations: [false, false],
+  },
+  {
+    description: "Form with only a hidden field",
+    document: `<form>
+      <input id="un1" type="hidden" autocomplete="username">
+      </form>`,
+    expectations: [false, false],
+  },
+  {
+    description: "Form with only a button",
+    document: `<form>
+      <input id="un1" type="button" autocomplete="username">
+      </form>`,
+    expectations: [false, false],
+  },
+  {
+    description: "A username only form matches not username selector",
+    document: `<form>
+      <input id="un1" type="text" name="secret_username">
+      </form>`,
+    fieldOverrideRecipe: {
+      hosts: ["localhost:8080"],
+      notUsernameSelector: 'input[name="secret_username"]',
+    },
+    expectations: [false, false],
+  },
+];
+
+function _setPrefs() {
+  Services.prefs.setBoolPref("signon.usernameOnlyForm.enabled", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("signon.usernameOnlyForm.enabled");
+  });
+}
+
+_setPrefs();
+
+for (let tc of TESTCASES) {
+  info("Sanity checking the testcase: " + tc.description);
+
+  // A form is considered a username-only form
+  for (let formHasSigninKeyword of [false, true]) {
+    (function () {
+      const testcase = tc;
+      add_task(async function () {
+        if (formHasSigninKeyword) {
+          testcase.decription += " (form has a login keyword)";
+        }
+        info("Starting testcase: " + testcase.description);
+        info("Document string: " + testcase.document);
+        const document = MockDocument.createTestDocument(
+          "http://localhost:8080/test/",
+          testcase.document
+        );
+
+        let form = document.querySelector("form");
+        if (formHasSigninKeyword) {
+          form.setAttribute("name", "login");
+        }
+
+        const lmc = new LoginManagerChild();
+        const docState = lmc.stateForDocument(form.ownerDocument);
+        const element = docState.getUsernameFieldFromUsernameOnlyForm(
+          form,
+          testcase.fieldOverrideRecipe
+        );
+        Assert.strictEqual(
+          testcase.expectations[formHasSigninKeyword ? 1 : 0],
+          element != null,
+          `Return incorrect result when the layout is ${testcase.description}`
+        );
+      });
+    })();
+  }
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_isInferredLoginForm.js b/toolkit/components/passwordmgr/test/unit/test_isInferredLoginForm.js
new file mode 100644
index 0000000000..01bc3ff816
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_isInferredLoginForm.js
@@ -0,0 +1,98 @@
+/**
+ * Test for LoginHelper.isInferredLoginForm.
+ */
+
+"use strict";
+
+const attributeTestData = [
+  {
+    testValues: ["", "form", "search", "signup", "sign-up", "sign/up"],
+    expectation: false,
+  },
+  {
+    testValues: [
+      "Login",
+      "Log in",
+      "Log on",
+      "Log-on",
+      "Sign in",
+      "Sigin",
+      "Sign/in",
+      "Sign-in",
+      "Sign on",
+      "Sign-on",
+      "loginForm",
+      "form-sign-in",
+    ],
+    expectation: true,
+  },
+];
+
+const classNameTestData = [
+  {
+    testValues: [
+      "",
+      "inputTxt form-control",
+      "user-input form-name",
+      "text name mail",
+      "form signup",
+    ],
+    expectation: false,
+  },
+  {
+    testValues: ["login form"],
+    expectation: true,
+  },
+];
+
+const TESTCASES = [
+  {
+    description: "Test id attribute",
+    update: (doc, v) => {
+      doc.querySelector("form").setAttribute("id", v);
+    },
+    subtests: attributeTestData,
+  },
+  {
+    description: "Test name attribute",
+    update: (doc, v) => {
+      doc.querySelector("form").setAttribute("name", v);
+    },
+    subtests: attributeTestData,
+  },
+  {
+    description: "Test class attribute",
+    update: (doc, v) => {
+      doc.querySelector("form").setAttribute("class", v);
+    },
+    subtests: [...attributeTestData, ...classNameTestData],
+  },
+];
+
+for (let testcase of TESTCASES) {
+  info("Sanity checking the testcase: " + testcase.description);
+
+  (function () {
+    add_task(async function () {
+      info("Starting testcase: " + testcase.description);
+
+      for (let subtest of testcase.subtests) {
+        const document = MockDocument.createTestDocument(
+          "http://localhost:8080/test/",
+          `<form id="id" name="name"></form>`
+        );
+
+        for (let value of subtest.testValues) {
+          testcase.update(document, value);
+          const ele = document.querySelector("form");
+          const ret = LoginHelper.isInferredLoginForm(ele);
+          Assert.strictEqual(
+            ret,
+            subtest.expectation,
+            `${testcase.description}, isInferredLoginForm doesn't return correct result while setting the value to ${value}`
+          );
+        }
+      }
+    });
+  })();
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_isInferredUsernameField.js b/toolkit/components/passwordmgr/test/unit/test_isInferredUsernameField.js
new file mode 100644
index 0000000000..e7d0785e8d
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_isInferredUsernameField.js
@@ -0,0 +1,222 @@
+/**
+ * Test for LoginHelper.isInferredUsernameField and LoginHelper.isInferredEmailField.
+ */
+
+"use strict";
+
+const attributeTestData = [
+  {
+    testValues: [
+      "",
+      "name",
+      "e-mail",
+      "user",
+      "user name",
+      "userid",
+      "lastname",
+    ],
+    expectation: "none",
+  },
+  {
+    testValues: ["email", "EmaiL", "loginemail", "邮箱"],
+    expectation: "email",
+  },
+  {
+    testValues: ["username", "usErNaMe", "my username"],
+    expectation: "username",
+  },
+  {
+    testValues: ["usernameAndemail", "EMAILUSERNAME"],
+    expectation: "username,email",
+  },
+];
+
+const classNameTestData = [
+  {
+    testValues: [
+      "inputTxt form-control",
+      "user-input form-name",
+      "text name mail",
+    ],
+    expectation: "none",
+  },
+  {
+    testValues: ["input email", "signin-email form", "input form valid-Email"],
+    expectation: "email",
+  },
+  {
+    testValues: [
+      "input username",
+      "signup-username form",
+      "input form my_username",
+    ],
+    expectation: "username",
+  },
+  {
+    testValues: ["input text form username email"],
+    expectation: "username,email",
+  },
+];
+
+const labelTestData = [
+  {
+    testValues: [
+      "First Name",
+      "Last Name",
+      "Company Name",
+      "Password",
+      "User Name",
+    ],
+    expectation: "none",
+  },
+  {
+    testValues: ["Email:", "Email Address*"],
+    expectation: "email",
+  },
+  {
+    testValues: ["Username:", "choose a username"],
+    expectation: "username",
+  },
+  {
+    testValues: ["Username/Email", "username or email"],
+    expectation: "username,email",
+  },
+];
+
+const TESTCASES = [
+  {
+    description: "Test input type",
+    update: (doc, v) => {
+      doc.querySelector("input").setAttribute("type", v);
+    },
+    subtests: [
+      {
+        testValues: ["text", "url", "number", "username"],
+        expectation: "none",
+      },
+      {
+        testValues: ["email"],
+        expectation: "email",
+      },
+    ],
+  },
+  {
+    description: "Test autocomplete field",
+    update: (doc, v) => {
+      doc.querySelector("input").setAttribute("autocomplete", v);
+    },
+    subtests: [
+      {
+        testValues: [
+          "off",
+          "on",
+          "name",
+          "new-password",
+          "current-password",
+          "tel",
+          "tel-national",
+          "url",
+        ],
+        expectation: "none",
+      },
+      {
+        testValues: ["email"],
+        expectation: "email",
+      },
+      {
+        testValues: ["username"],
+        expectation: "username",
+      },
+    ],
+  },
+  {
+    description: "Test id attribute",
+    update: (doc, v) => {
+      doc.querySelector("input").setAttribute("id", v);
+    },
+    subtests: attributeTestData,
+  },
+  {
+    description: "Test name attribute",
+    update: (doc, v) => {
+      doc.querySelector("input").setAttribute("name", v);
+    },
+    subtests: attributeTestData,
+  },
+  {
+    description: "Test class attribute",
+    update: (doc, v) => {
+      doc.querySelector("input").setAttribute("class", v);
+    },
+    subtests: [...attributeTestData, ...classNameTestData],
+  },
+  {
+    description: "Test placeholder attribute",
+    update: (doc, v) => {
+      doc.querySelector("input").setAttribute("placeholder", v);
+    },
+    subtests: attributeTestData,
+  },
+  {
+    description: "Test the first label",
+    update: (doc, v) => {
+      doc.getElementById("l1").textContent = v;
+    },
+    subtests: labelTestData,
+  },
+  {
+    description: "Test the second label",
+    update: (doc, v) => {
+      doc.getElementById("l2").textContent = v;
+    },
+    subtests: labelTestData,
+
+    // The username detection heuristic only examine the first label associated
+    // with the input, so no matter what the data is for this label, it doesn't
+    // affect the result.
+    // We can update this testcase once we decide to support multiple labels.
+    supported: false,
+  },
+];
+
+for (let testcase of TESTCASES) {
+  info("Sanity checking the testcase: " + testcase.description);
+
+  (function () {
+    add_task(async function () {
+      info("Starting testcase: " + testcase.description);
+
+      for (let subtest of testcase.subtests) {
+        let document = MockDocument.createTestDocument(
+          "http://localhost:8080/test/",
+          `<label id="l1" for="id"></label>
+           <label id="l2" for="id"></label>
+           <input id="id" type="text" name="name">`
+        );
+
+        for (let value of subtest.testValues) {
+          testcase.update(document, value);
+          let ele = document.querySelector("input");
+
+          let ret = LoginHelper.isInferredUsernameField(ele);
+          Assert.strictEqual(
+            ret,
+            testcase.supported !== false
+              ? subtest.expectation.includes("username")
+              : false,
+            `${testcase.description}, isInferredUsernameField doesn't return correct result while setting the value to ${value}`
+          );
+
+          ret = LoginHelper.isInferredEmailField(ele);
+          Assert.strictEqual(
+            ret,
+            testcase.supported !== false
+              ? subtest.expectation.includes("email")
+              : false,
+            `${testcase.description}, isInferredEmailField doesn't return correct result while setting the value to ${value}`
+          );
+        }
+      }
+    });
+  })();
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_isOriginMatching.js b/toolkit/components/passwordmgr/test/unit/test_isOriginMatching.js
new file mode 100644
index 0000000000..02547609ec
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_isOriginMatching.js
@@ -0,0 +1,177 @@
+/**
+ * Test LoginHelper.isOriginMatching
+ */
+
+"use strict";
+
+add_task(function test_isOriginMatching() {
+  let testcases = [
+    // Index 0 holds the expected return value followed by arguments to isOriginMatching.
+    [true, "http://example.com", "http://example.com"],
+    [true, "http://example.com:8080", "http://example.com:8080"],
+    [true, "https://example.com", "https://example.com"],
+    [true, "https://example.com:8443", "https://example.com:8443"],
+
+    // The formActionOrigin can be "javascript:"
+    [true, "javascript:", "javascript:"],
+    [false, "javascript:", "http://example.com"],
+    [false, "http://example.com", "javascript:"],
+
+    // HTTP Auth. logins have a null formActionOrigin
+    [true, null, null],
+    [false, null, "http://example.com"],
+    [false, "http://example.com", null],
+
+    [false, "http://example.com", "http://mozilla.org"],
+    [false, "http://example.com", "http://example.com:8080"],
+    [false, "https://example.com", "http://example.com"],
+    [false, "https://example.com", "https://mozilla.org"],
+    [false, "http://example.com", "http://sub.example.com"],
+    [false, "https://example.com", "https://sub.example.com"],
+    [false, "http://example.com", "https://example.com:8443"],
+    [false, "http://example.com:8080", "http://example.com:8081"],
+    [false, "http://example.com", ""],
+    [false, "", "http://example.com"],
+    [
+      true,
+      "http://example.com",
+      "https://example.com",
+      { schemeUpgrades: true },
+    ],
+    [
+      true,
+      "https://example.com",
+      "https://example.com",
+      { schemeUpgrades: true },
+    ],
+    [
+      true,
+      "http://example.com:8080",
+      "http://example.com:8080",
+      { schemeUpgrades: true },
+    ],
+    [
+      true,
+      "https://example.com:8443",
+      "https://example.com:8443",
+      { schemeUpgrades: true },
+    ],
+    [
+      false,
+      "https://example.com",
+      "http://example.com",
+      { schemeUpgrades: true },
+    ], // downgrade
+    [
+      false,
+      "http://example.com:8080",
+      "https://example.com",
+      { schemeUpgrades: true },
+    ], // port mismatch
+    [
+      false,
+      "http://example.com",
+      "https://example.com:8443",
+      { schemeUpgrades: true },
+    ], // port mismatch
+    [
+      false,
+      "http://sub.example.com",
+      "http://example.com",
+      { schemeUpgrades: true },
+    ],
+    [
+      true,
+      "http://sub.example.com",
+      "http://example.com",
+      { acceptDifferentSubdomains: true },
+    ],
+    [
+      true,
+      "http://sub.sub.example.com",
+      "http://example.com",
+      { acceptDifferentSubdomains: true },
+    ],
+    [
+      true,
+      "http://example.com",
+      "http://sub.example.com",
+      { acceptDifferentSubdomains: true },
+    ],
+    [
+      true,
+      "http://example.com",
+      "http://sub.sub.example.com",
+      { acceptDifferentSubdomains: true },
+    ],
+    [
+      false,
+      "https://sub.example.com",
+      "http://example.com",
+      { acceptDifferentSubdomains: true, schemeUpgrades: true },
+    ],
+    [
+      true,
+      "http://sub.example.com",
+      "https://example.com",
+      { acceptDifferentSubdomains: true, schemeUpgrades: true },
+    ],
+    [
+      true,
+      "http://sub.example.com",
+      "http://example.com:8081",
+      { acceptDifferentSubdomains: true },
+    ],
+    [
+      false,
+      "http://sub.example.com",
+      "http://sub.example.mozilla.com",
+      { acceptDifferentSubdomains: true },
+    ],
+    // signon.includeOtherSubdomainsInLookup allows acceptDifferentSubdomains to be false
+    [
+      false,
+      "http://sub.example.com",
+      "http://example.com",
+      { acceptDifferentSubdomains: false },
+    ],
+    [
+      false,
+      "http://sub.sub.example.com",
+      "http://example.com",
+      { acceptDifferentSubdomains: false },
+    ],
+    [
+      false,
+      "http://sub.example.com",
+      "http://example.com:8081",
+      { acceptDifferentSubdomains: false },
+    ],
+    [
+      false,
+      "http://sub.example.com",
+      "http://sub.example.mozilla.com",
+      { acceptDifferentSubdomains: false },
+    ],
+
+    // HTTP Auth. logins have a null formActionOrigin
+    [
+      false,
+      null,
+      "http://example.com",
+      {
+        acceptDifferentSubdomains: false,
+        acceptWildcardMatch: true,
+        schemeUpgrades: true,
+      },
+    ],
+  ];
+  for (let tc of testcases) {
+    let expected = tc.shift();
+    Assert.strictEqual(
+      LoginHelper.isOriginMatching(...tc),
+      expected,
+      "Check " + JSON.stringify(tc)
+    );
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_isProbablyANewPasswordField.js b/toolkit/components/passwordmgr/test/unit/test_isProbablyANewPasswordField.js
new file mode 100644
index 0000000000..167c160da2
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_isProbablyANewPasswordField.js
@@ -0,0 +1,192 @@
+/**
+ * Test for LoginAutoComplete.isProbablyANewPasswordField.
+ */
+
+"use strict";
+
+const LoginAutoComplete = Cc[
+  "@mozilla.org/login-manager/autocompletesearch;1"
+].getService(Ci.nsILoginAutoCompleteSearch).wrappedJSObject;
+// TODO: create a fake window for the test document to pass fathom.isVisible check.
+// We should consider moving these tests to mochitest because many fathom
+// signals rely on visibility, position, etc., of the test element (See Bug 1712699),
+// which is not supported in xpcshell-test.
+function makeDocumentVisibleToFathom(doc) {
+  let win = {
+    getComputedStyle() {
+      return {
+        overflow: "visible",
+        visibility: "visible",
+      };
+    },
+  };
+  Object.defineProperty(doc, "defaultView", {
+    value: win,
+  });
+  return doc;
+}
+
+function labelledByDocument() {
+  let doc = MockDocument.createTestDocument(
+    "http://localhost:8080/test/",
+    `<div>
+       <label id="paper-input-label-2">Password</label>
+       <input aria-labelledby="paper-input-label-2" type="password">
+     </div>`
+  );
+  let div = doc.querySelector("div");
+  // Put the div contents inside shadow DOM.
+  div.attachShadow({ mode: "open" }).append(...div.children);
+  return doc;
+}
+const LABELLEDBY_SHADOW_TESTCASE = labelledByDocument();
+
+const TESTCASES = [
+  // Note there is no test case for `<input type="password" autocomplete="new-password">`
+  // since isProbablyANewPasswordField explicitly does not run in that case.
+  {
+    description: "Basic login form",
+    document: `
+      <h1>Sign in</h1>
+      <form>
+        <label>Username: <input type="text" name="username"></label>
+        <label>Password: <input type="password" name="password"></label>
+        <input type="submit" value="Sign in">
+      </form>
+    `,
+    expectedResult: [false],
+  },
+  {
+    description: "Basic registration form",
+    document: `
+      <h1>Create account</h1>
+      <form>
+        <label>Username: <input type="text" name="username"></label>
+        <label>Password: <input type="password" name="new-password"></label>
+        <input type="submit" value="Register">
+      </form>
+    `,
+    expectedResult: [true],
+  },
+  {
+    // TODO: Add <placeholder="confirm"> to "confirm-passowrd" password field so fathom can recognize it
+    // as a new password field. Currently, the fathom rules don't really work well in xpcshell-test
+    // because signals rely on visibility, position doesn't work. If we move this test to mochitest, we should
+    // be able to remove the interim solution (See Bug 1712699).
+    description: "Basic password change form",
+    document: `
+      <h1>Change password</h1>
+      <form>
+        <label>Current Password: <input type="password" name="current-password"></label>
+        <label>New Password: <input type="password" name="new-password"></label>
+        <label>Confirm Password: <input type="password" name="confirm-password" placeholder="confirm"></label>
+        <input type="submit" value="Save">
+      </form>
+    `,
+    expectedResult: [false, true, true],
+  },
+  {
+    description: "Basic login 'form' without a form element",
+    document: `
+      <h1>Sign in</h1>
+      <label>Username: <input type="text" name="username"></label>
+      <label>Password: <input type="password" name="password"></label>
+      <input type="submit" value="Sign in">
+    `,
+    expectedResult: [false],
+  },
+  {
+    description: "Basic registration 'form' without a form element",
+    document: `
+      <h1>Create account</h1>
+      <label>Username: <input type="text" name="username"></label>
+      <label>Password: <input type="password" name="new-password"></label>
+      <input type="submit" value="Register">
+    `,
+    expectedResult: [true],
+  },
+  {
+    description: "Basic password change 'form' without a form element",
+    document: `
+      <h1>Change password</h1>
+      <label>Current Password: <input type="password" name="current-password"></label>
+      <label>New Password: <input type="password" name="new-password"></label>
+      <label>Confirm Password: <input type="password" name="confirm-password"></label>
+      <input type="submit" value="Save">
+    `,
+    expectedResult: [false, true, true],
+  },
+  {
+    description: "Password field with aria-labelledby inside shadow DOM",
+    document: LABELLEDBY_SHADOW_TESTCASE,
+    inputs: LABELLEDBY_SHADOW_TESTCASE.querySelector(
+      "div"
+    ).shadowRoot.querySelectorAll("input[type='password']"),
+    expectedResult: [false],
+  },
+];
+
+add_task(async function test_returns_false_when_pref_disabled() {
+  const threshold = Services.prefs.getStringPref(
+    NEW_PASSWORD_HEURISTIC_ENABLED_PREF
+  );
+
+  info("Temporarily disabling new-password heuristic pref");
+  Services.prefs.setStringPref(NEW_PASSWORD_HEURISTIC_ENABLED_PREF, "-1");
+
+  // Use registration form test case, where we know it should return true if enabled
+  const testcase = TESTCASES[1];
+  info("Starting testcase: " + testcase.description);
+  const document = Document.isInstance(testcase.document)
+    ? testcase.document
+    : MockDocument.createTestDocument(
+        "http://localhost:8080/test/",
+        testcase.document
+      );
+  for (let [i, input] of testcase.inputs ||
+    document.querySelectorAll(`input[type="password"]`).entries()) {
+    const result = LoginAutoComplete.isProbablyANewPasswordField(input);
+    Assert.strictEqual(
+      result,
+      false,
+      `When the pref is set to disable, the result is always false, e.g. for the testcase, ${testcase.description} ${i}`
+    );
+  }
+
+  info("Re-enabling new-password heuristic pref");
+  Services.prefs.setStringPref(NEW_PASSWORD_HEURISTIC_ENABLED_PREF, threshold);
+});
+
+for (let testcase of TESTCASES) {
+  info("Sanity checking the testcase: " + testcase.description);
+
+  (function () {
+    add_task(async function () {
+      info("Starting testcase: " + testcase.description);
+      let document = Document.isInstance(testcase.document)
+        ? testcase.document
+        : MockDocument.createTestDocument(
+            "http://localhost:8080/test/",
+            testcase.document
+          );
+
+      document = makeDocumentVisibleToFathom(document);
+
+      const results = [];
+      for (let input of testcase.inputs ||
+        document.querySelectorAll(`input[type="password"]`)) {
+        const result = LoginAutoComplete.isProbablyANewPasswordField(input);
+        results.push(result);
+      }
+
+      for (let i = 0; i < testcase.expectedResult.length; i++) {
+        let expectedResult = testcase.expectedResult[i];
+        Assert.strictEqual(
+          results[i],
+          expectedResult,
+          `In the test case, ${testcase.description}, check if password field #${i} is a new password field.`
+        );
+      }
+    });
+  })();
+}
diff --git a/toolkit/components/passwordmgr/test/unit/test_isUsernameFieldType.js b/toolkit/components/passwordmgr/test/unit/test_isUsernameFieldType.js
new file mode 100644
index 0000000000..57238964a7
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_isUsernameFieldType.js
@@ -0,0 +1,160 @@
+/**
+ * Test for LoginHelper.isUsernameFieldType
+ */
+
+"use strict";
+
+const autocompleteTypes = {
+  "": true,
+  on: true,
+  off: true,
+  name: false,
+  "unrecognized-type": true,
+  "given-name": false,
+  "additional-name": false,
+  "family-name": false,
+  nickname: false,
+  username: true,
+  "new-password": false,
+  "current-password": false,
+  "organization-title": false,
+  organization: false,
+  "street-address": false,
+  "address-line1": false,
+  "address-line2": false,
+  "address-line3": false,
+  "address-level4": false,
+  "address-level3": false,
+  "address-level2": false,
+  "address-level1": false,
+  country: false,
+  "country-name": false,
+  "postal-code": false,
+  "cc-name": false,
+  "cc-given-name": false,
+  "cc-additional-name": false,
+  "cc-family-name": false,
+  "cc-number": false,
+  "cc-exp": false,
+  "cc-exp-month": false,
+  "cc-exp-year": false,
+  "cc-csc": false,
+  "cc-type": false,
+  "transaction-currency": false,
+  "transaction-amount": false,
+  language: false,
+  bday: false,
+  "bday-day": false,
+  "bday-month": false,
+  "bday-year": false,
+  sex: false,
+  url: false,
+  photo: false,
+  tel: true,
+  "tel-country-code": false,
+  "tel-national": true,
+  "tel-area-code": false,
+  "tel-local": false,
+  "tel-local-prefix": false,
+  "tel-local-suffix": false,
+  "tel-extension": false,
+  email: true,
+  impp: false,
+};
+
+const TESTCASES = [
+  {
+    description: "type=text",
+    document: `<input type="text">`,
+    expected: true,
+  },
+  {
+    description: "type=email, no autocomplete attribute",
+    document: `<input type="email">`,
+    expected: true,
+  },
+  {
+    description: "type=url, no autocomplete attribute",
+    document: `<input type="url">`,
+    expected: true,
+  },
+  {
+    description: "type=tel, no autocomplete attribute",
+    document: `<input type="tel">`,
+    expected: true,
+  },
+  {
+    description: "type=number, no autocomplete attribute",
+    document: `<input type="number">`,
+    expected: true,
+  },
+  {
+    description: "type=search, no autocomplete attribute",
+    document: `<input type="search">`,
+    expected: true,
+  },
+  {
+    description: "type=range, no autocomplete attribute",
+    document: `<input type="range">`,
+    expected: false,
+  },
+  {
+    description: "type=date, no autocomplete attribute",
+    document: `<input type="date">`,
+    expected: false,
+  },
+  {
+    description: "type=month, no autocomplete attribute",
+    document: `<input type="month">`,
+    expected: false,
+  },
+  {
+    description: "type=week, no autocomplete attribute",
+    document: `<input type="week">`,
+    expected: false,
+  },
+  {
+    description: "type=time, no autocomplete attribute",
+    document: `<input type="time">`,
+    expected: false,
+  },
+  {
+    description: "type=datetime, no autocomplete attribute",
+    document: `<input type="datetime">`,
+    expected: false,
+  },
+  {
+    description: "type=datetime-local, no autocomplete attribute",
+    document: `<input type="datetime-local">`,
+    expected: false,
+  },
+  {
+    description: "type=color, no autocomplete attribute",
+    document: `<input type="color">`,
+    expected: false,
+  },
+];
+
+for (let [name, expected] of Object.entries(autocompleteTypes)) {
+  TESTCASES.push({
+    description: `type=text autocomplete=${name}`,
+    document: `<input type="text" autocomplete="${name}">`,
+    expected,
+  });
+}
+
+TESTCASES.forEach(testcase => {
+  add_task(async function () {
+    info("Starting testcase: " + testcase.description);
+    let document = MockDocument.createTestDocument(
+      "http://localhost:8080/test/",
+      testcase.document
+    );
+    let input = document.querySelector("input");
+    Assert.equal(
+      LoginHelper.isUsernameFieldType(input),
+      testcase.expected,
+      testcase.description
+    );
+  });
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_legacy_empty_formActionOrigin.js b/toolkit/components/passwordmgr/test/unit/test_legacy_empty_formActionOrigin.js
new file mode 100644
index 0000000000..d630ed0e07
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_legacy_empty_formActionOrigin.js
@@ -0,0 +1,112 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests the legacy case of a login store containing entries that have an empty
+ * string in the formActionOrigin field.
+ *
+ * In normal conditions, for the purpose of login autocomplete, HTML forms are
+ * identified using both the prePath of the URI on which they are located, and
+ * the prePath of the URI where the data will be submitted.  This is represented
+ * by the origin and formActionOrigin properties of the stored nsILoginInfo.
+ *
+ * When a new login for use in forms is saved (after the user replies to the
+ * password prompt), it is always stored with both the origin and the
+ * formActionOrigin (that will be equal to the origin when the form has no
+ * "action" attribute).
+ *
+ * When the same form is displayed again, the password is autocompleted.  If
+ * there is another form on the same site that submits to a different site, it
+ * is considered a different form, so the password is not autocompleted, but a
+ * new password can be stored for the other form.
+ *
+ * However, the login database might contain data for an nsILoginInfo that has a
+ * valid origin, but an empty formActionOrigin.  This means that the login
+ * applies to all forms on the site, regardless of where they submit data to.
+ *
+ * A site can have at most one such login, and in case it is present, then it is
+ * not possible to store separate logins for forms on the same site that submit
+ * data to different sites.
+ *
+ * The only way to have such condition is to be using logins that were initially
+ * saved by a very old version of the browser, or because of data manually added
+ * by an extension in an old version.
+ */
+
+"use strict";
+
+// Tests
+
+/**
+ * Adds a login with an empty formActionOrigin, then it verifies that no other
+ * form logins can be added for the same host.
+ */
+add_task(async function test_addLogin_wildcard() {
+  let loginInfo = TestData.formLogin({
+    origin: "http://any.example.com",
+    formActionOrigin: "",
+  });
+  await Services.logins.addLoginAsync(loginInfo);
+
+  // Normal form logins cannot be added anymore.
+  loginInfo = TestData.formLogin({ origin: "http://any.example.com" });
+  await Assert.rejects(
+    Services.logins.addLoginAsync(loginInfo),
+    /already exists/
+  );
+
+  // Authentication logins can still be added.
+  loginInfo = TestData.authLogin({ origin: "http://any.example.com" });
+  await Services.logins.addLoginAsync(loginInfo);
+
+  // Form logins can be added for other hosts.
+  loginInfo = TestData.formLogin({ origin: "http://other.example.com" });
+  await Services.logins.addLoginAsync(loginInfo);
+});
+
+/**
+ * Verifies that searchLogins and countLogins include all logins
+ * that have an empty formActionOrigin in the store, even when a formActionOrigin is
+ * specified.
+ */
+add_task(function test_search_all_wildcard() {
+  // Search a given formActionOrigin on any host.
+  let matchData = newPropertyBag({
+    formActionOrigin: "http://www.example.com",
+  });
+  Assert.equal(Services.logins.searchLogins(matchData).length, 2);
+
+  Assert.equal(
+    Services.logins.countLogins("", "http://www.example.com", null),
+    2
+  );
+
+  // Restrict the search to one host.
+  matchData.setProperty("origin", "http://any.example.com");
+  Assert.equal(Services.logins.searchLogins(matchData).length, 1);
+
+  Assert.equal(
+    Services.logins.countLogins(
+      "http://any.example.com",
+      "http://www.example.com",
+      null
+    ),
+    1
+  );
+});
+
+/**
+ * Verifies that specifying an empty string for formActionOrigin in searchLogins
+ * includes only logins that have an empty formActionOrigin in the store.
+ */
+add_task(function test_searchLogins_wildcard() {
+  let logins = Services.logins.searchLogins(
+    newPropertyBag({ formActionOrigin: "" })
+  );
+
+  let loginInfo = TestData.formLogin({
+    origin: "http://any.example.com",
+    formActionOrigin: "",
+  });
+  LoginTestUtils.assertLoginListsEqual(logins, [loginInfo]);
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_legacy_validation.js b/toolkit/components/passwordmgr/test/unit/test_legacy_validation.js
new file mode 100644
index 0000000000..7fb6c9807d
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_legacy_validation.js
@@ -0,0 +1,94 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests the legacy validation made when storing nsILoginInfo or disabled hosts.
+ *
+ * These rules exist because of limitations of the "signons.txt" storage file,
+ * that is not used anymore.  They are still enforced by the Login Manager
+ * service, despite these values can now be safely stored in the back-end.
+ */
+
+"use strict";
+
+// Tests
+
+/**
+ * Tests legacy validation with addLogin.
+ */
+add_task(async function test_addLogin_invalid_characters_legacy() {
+  // Test newlines and carriage returns in properties that contain URLs.
+  for (let testValue of [
+    "http://newline\n.example.com",
+    "http://carriagereturn.example.com\r",
+  ]) {
+    let loginInfo = TestData.formLogin({ origin: testValue });
+    await Assert.rejects(
+      Services.logins.addLoginAsync(loginInfo),
+      /login values can't contain newlines/
+    );
+
+    loginInfo = TestData.formLogin({ formActionOrigin: testValue });
+    await Assert.rejects(
+      Services.logins.addLoginAsync(loginInfo),
+      /login values can't contain newlines/
+    );
+
+    loginInfo = TestData.authLogin({ httpRealm: testValue });
+    await Assert.rejects(
+      Services.logins.addLoginAsync(loginInfo),
+      /login values can't contain newlines/
+    );
+  }
+
+  // Test newlines and carriage returns in form field names.
+  for (let testValue of ["newline_field\n", "carriagereturn\r_field"]) {
+    let loginInfo = TestData.formLogin({ usernameField: testValue });
+    await Assert.rejects(
+      Services.logins.addLoginAsync(loginInfo),
+      /login values can't contain newlines/
+    );
+
+    loginInfo = TestData.formLogin({ passwordField: testValue });
+    await Assert.rejects(
+      Services.logins.addLoginAsync(loginInfo),
+      /login values can't contain newlines/
+    );
+  }
+
+  // Test a single dot as the value of usernameField and formActionOrigin.
+  let loginInfo = TestData.formLogin({ usernameField: "." });
+  await Assert.rejects(
+    Services.logins.addLoginAsync(loginInfo),
+    /login values can't be periods/
+  );
+
+  loginInfo = TestData.formLogin({ formActionOrigin: "." });
+  await Assert.rejects(
+    Services.logins.addLoginAsync(loginInfo),
+    /login values can't be periods/
+  );
+
+  // Test the sequence " (" inside the value of the "origin" property.
+  loginInfo = TestData.formLogin({ origin: "http://parens (.example.com" });
+  await Assert.rejects(
+    Services.logins.addLoginAsync(loginInfo),
+    /bad parens in origin/
+  );
+});
+
+/**
+ * Tests legacy validation with setLoginSavingEnabled.
+ */
+add_task(function test_setLoginSavingEnabled_invalid_characters_legacy() {
+  for (let origin of [
+    "http://newline\n.example.com",
+    "http://carriagereturn.example.com\r",
+    ".",
+  ]) {
+    Assert.throws(
+      () => Services.logins.setLoginSavingEnabled(origin, false),
+      /Invalid origin/
+    );
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_login_autocomplete_result.js b/toolkit/components/passwordmgr/test/unit/test_login_autocomplete_result.js
new file mode 100644
index 0000000000..79a3c4bb4a
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_login_autocomplete_result.js
@@ -0,0 +1,735 @@
+const { LoginAutoCompleteResult } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginAutoComplete.sys.mjs"
+);
+let nsLoginInfo = Components.Constructor(
+  "@mozilla.org/login-manager/loginInfo;1",
+  Ci.nsILoginInfo,
+  "init"
+);
+
+const PREF_SCHEME_UPGRADES = "signon.schemeUpgrades";
+
+let matchingLogins = [];
+matchingLogins.push(
+  new nsLoginInfo(
+    "https://mochi.test:8888",
+    "https://autocomplete:8888",
+    null,
+    "",
+    "emptypass1",
+    "uname",
+    "pword"
+  )
+);
+
+matchingLogins.push(
+  new nsLoginInfo(
+    "https://mochi.test:8888",
+    "https://autocomplete:8888",
+    null,
+    "tempuser1",
+    "temppass1",
+    "uname",
+    "pword"
+  )
+);
+
+matchingLogins.push(
+  new nsLoginInfo(
+    "https://mochi.test:8888",
+    "https://autocomplete:8888",
+    null,
+    "testuser2",
+    "testpass2",
+    "uname",
+    "pword"
+  )
+);
+// subdomain:
+matchingLogins.push(
+  new nsLoginInfo(
+    "https://sub.mochi.test:8888",
+    "https://autocomplete:8888",
+    null,
+    "testuser3",
+    "testpass3",
+    "uname",
+    "pword"
+  )
+);
+
+// to test signon.schemeUpgrades
+matchingLogins.push(
+  new nsLoginInfo(
+    "http://mochi.test:8888",
+    "http://autocomplete:8888",
+    null,
+    "zzzuser4",
+    "zzzpass4",
+    "uname",
+    "pword"
+  )
+);
+
+// HTTP auth
+matchingLogins.push(
+  new nsLoginInfo(
+    "https://mochi.test:8888",
+    null,
+    "My HTTP auth realm",
+    "httpuser",
+    "httppass"
+  )
+);
+
+add_setup(async () => {
+  // Get a profile so we have storage access and insert the logins to get unique GUIDs.
+  do_get_profile();
+  matchingLogins = await Services.logins.addLogins(matchingLogins);
+});
+
+add_task(async function test_all_patterns() {
+  let meta = matchingLogins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  let dateAndTimeFormatter = new Services.intl.DateTimeFormat(undefined, {
+    dateStyle: "medium",
+  });
+  let time = dateAndTimeFormatter.format(new Date(meta.timePasswordChanged));
+  const LABEL_NO_USERNAME = "No username (" + time + ")";
+  const EXACT_ORIGIN_MATCH_COMMENT = "From this website";
+
+  let expectedResults = [
+    {
+      isSecure: true,
+      hasBeenTypePassword: false,
+      matchingLogins,
+      items: [
+        {
+          value: "",
+          label: LABEL_NO_USERNAME,
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "tempuser1",
+          label: "tempuser1",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "testuser2",
+          label: "testuser2",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "zzzuser4",
+          label: "zzzuser4",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "httpuser",
+          label: "httpuser",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888 (My HTTP auth realm)" },
+        },
+        {
+          value: "testuser3",
+          label: "testuser3",
+          style: "loginWithOrigin",
+          comment: { comment: "sub.mochi.test:8888" },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: {
+            formHostname: "mochi.test",
+            telemetryEventData: { searchStartTimeMS: 0 },
+          },
+        },
+      ],
+    },
+    {
+      isSecure: false,
+      hasBeenTypePassword: false,
+      matchingLogins: [],
+      items: [
+        {
+          value: "",
+          label:
+            "This connection is not secure. Logins entered here could be compromised. Learn More",
+          style: "insecureWarning",
+          comment: "",
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: {
+            formHostname: "mochi.test",
+            telemetryEventData: { searchStartTimeMS: 1 },
+          },
+        },
+      ],
+    },
+    {
+      isSecure: false,
+      hasBeenTypePassword: false,
+      matchingLogins,
+      items: [
+        {
+          value: "",
+          label:
+            "This connection is not secure. Logins entered here could be compromised. Learn More",
+          style: "insecureWarning",
+          comment: "",
+        },
+        {
+          value: "",
+          label: LABEL_NO_USERNAME,
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "tempuser1",
+          label: "tempuser1",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "testuser2",
+          label: "testuser2",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "zzzuser4",
+          label: "zzzuser4",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "httpuser",
+          label: "httpuser",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888 (My HTTP auth realm)" },
+        },
+        {
+          value: "testuser3",
+          label: "testuser3",
+          style: "loginWithOrigin",
+          comment: { comment: "sub.mochi.test:8888" },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      isSecure: true,
+      hasBeenTypePassword: true,
+      matchingLogins,
+      items: [
+        {
+          value: "emptypass1",
+          label: LABEL_NO_USERNAME,
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "temppass1",
+          label: "tempuser1",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "testpass2",
+          label: "testuser2",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "zzzpass4",
+          label: "zzzuser4",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "httppass",
+          label: "httpuser",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888 (My HTTP auth realm)" },
+        },
+        {
+          value: "testpass3",
+          label: "testuser3",
+          style: "loginWithOrigin",
+          comment: { comment: "sub.mochi.test:8888" },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      isSecure: false,
+      hasBeenTypePassword: true,
+      matchingLogins,
+      items: [
+        {
+          value: "",
+          label:
+            "This connection is not secure. Logins entered here could be compromised. Learn More",
+          style: "insecureWarning",
+          comment: "",
+        },
+        {
+          value: "emptypass1",
+          label: LABEL_NO_USERNAME,
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "temppass1",
+          label: "tempuser1",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "testpass2",
+          label: "testuser2",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "zzzpass4",
+          label: "zzzuser4",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "httppass",
+          label: "httpuser",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888 (My HTTP auth realm)" },
+        },
+        {
+          value: "testpass3",
+          label: "testuser3",
+          style: "loginWithOrigin",
+          comment: { comment: "sub.mochi.test:8888" },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      isSecure: true,
+      hasBeenTypePassword: false,
+      matchingLogins,
+      items: [
+        {
+          value: "",
+          label: LABEL_NO_USERNAME,
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "tempuser1",
+          label: "tempuser1",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "testuser2",
+          label: "testuser2",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "zzzuser4",
+          label: "zzzuser4",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "httpuser",
+          label: "httpuser",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888 (My HTTP auth realm)" },
+        },
+        {
+          value: "testuser3",
+          label: "testuser3",
+          style: "loginWithOrigin",
+          comment: { comment: "sub.mochi.test:8888" },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      isSecure: false,
+      hasBeenTypePassword: false,
+      matchingLogins: [],
+      searchString: "foo",
+      items: [
+        {
+          value: "",
+          label:
+            "This connection is not secure. Logins entered here could be compromised. Learn More",
+          style: "insecureWarning",
+          comment: "",
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      isSecure: true,
+      hasBeenTypePassword: true,
+      matchingLogins: [],
+      items: [
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      isSecure: true,
+      hasBeenTypePassword: true,
+      matchingLogins: [],
+      searchString: "foo",
+      items: [],
+    },
+    {
+      generatedPassword: "9ljgfd4shyktb45",
+      isSecure: true,
+      hasBeenTypePassword: true,
+      matchingLogins: [],
+      items: [
+        {
+          value: "9ljgfd4shyktb45",
+          label: "Use a Securely Generated Password",
+          style: "generatedPassword",
+          comment: {
+            generatedPassword: "9ljgfd4shyktb45",
+            willAutoSaveGeneratedPassword: false,
+          },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      description:
+        "willAutoSaveGeneratedPassword should propagate to the comment",
+      generatedPassword: "9ljgfd4shyktb45",
+      willAutoSaveGeneratedPassword: true,
+      isSecure: true,
+      hasBeenTypePassword: true,
+      matchingLogins: [],
+      items: [
+        {
+          value: "9ljgfd4shyktb45",
+          label: "Use a Securely Generated Password",
+          style: "generatedPassword",
+          comment: {
+            generatedPassword: "9ljgfd4shyktb45",
+            willAutoSaveGeneratedPassword: true,
+          },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      description:
+        "If a generated password is passed then show it even if there is a search string. This handles when forcing the generation option from the context menu of a non-empty field",
+      generatedPassword: "9ljgfd4shyktb45",
+      isSecure: true,
+      hasBeenTypePassword: true,
+      matchingLogins: [],
+      searchString: "9ljgfd4shyktb45",
+      items: [
+        {
+          value: "9ljgfd4shyktb45",
+          label: "Use a Securely Generated Password",
+          style: "generatedPassword",
+          comment: {
+            generatedPassword: "9ljgfd4shyktb45",
+            willAutoSaveGeneratedPassword: false,
+          },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      description: "secure username field on sub.mochi.test",
+      formOrigin: "https://sub.mochi.test:8888",
+      isSecure: true,
+      hasBeenTypePassword: false,
+      matchingLogins,
+      items: [
+        {
+          value: "testuser3",
+          label: "testuser3",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "",
+          label: LABEL_NO_USERNAME,
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888" },
+        },
+        {
+          value: "tempuser1",
+          label: "tempuser1",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888" },
+        },
+        {
+          value: "testuser2",
+          label: "testuser2",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888" },
+        },
+        {
+          value: "zzzuser4",
+          label: "zzzuser4",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888" },
+        },
+        {
+          value: "httpuser",
+          label: "httpuser",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888 (My HTTP auth realm)" },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      description: "secure password field on sub.mochi.test",
+      formOrigin: "https://sub.mochi.test:8888",
+      isSecure: true,
+      hasBeenTypePassword: true,
+      matchingLogins,
+      items: [
+        {
+          value: "testpass3",
+          label: "testuser3",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "emptypass1",
+          label: LABEL_NO_USERNAME,
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888" },
+        },
+        {
+          value: "temppass1",
+          label: "tempuser1",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888" },
+        },
+        {
+          value: "testpass2",
+          label: "testuser2",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888" },
+        },
+        {
+          value: "zzzpass4",
+          label: "zzzuser4",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888" },
+        },
+        {
+          value: "httppass",
+          label: "httpuser",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888 (My HTTP auth realm)" },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+    {
+      description: "schemeUpgrades: false",
+      formOrigin: "https://mochi.test:8888",
+      schemeUpgrades: false,
+      isSecure: true,
+      hasBeenTypePassword: false,
+      matchingLogins,
+      items: [
+        {
+          value: "",
+          label: LABEL_NO_USERNAME,
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "tempuser1",
+          label: "tempuser1",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "testuser2",
+          label: "testuser2",
+          style: "loginWithOrigin",
+          comment: { comment: EXACT_ORIGIN_MATCH_COMMENT },
+        },
+        {
+          value: "zzzuser4",
+          label: "zzzuser4",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888" },
+        },
+        {
+          value: "httpuser",
+          label: "httpuser",
+          style: "loginWithOrigin",
+          comment: { comment: "mochi.test:8888 (My HTTP auth realm)" },
+        },
+        {
+          value: "testuser3",
+          label: "testuser3",
+          style: "loginWithOrigin",
+          comment: { comment: "sub.mochi.test:8888" },
+        },
+        {
+          value: "",
+          label: "Manage Passwords",
+          style: "loginsFooter",
+          comment: { formHostname: "mochi.test" },
+        },
+      ],
+    },
+  ];
+
+  LoginHelper.createLogger("LoginAutoCompleteResult");
+  Services.prefs.setBoolPref("signon.showAutoCompleteFooter", true);
+
+  expectedResults.forEach((pattern, testIndex) => {
+    info(`expectedResults[${testIndex}]`);
+    info(JSON.stringify(pattern, null, 2));
+    Services.prefs.setBoolPref(
+      PREF_SCHEME_UPGRADES,
+      "schemeUpgrades" in pattern ? pattern.schemeUpgrades : true
+    );
+    let actual = new LoginAutoCompleteResult(
+      pattern.searchString || "",
+      pattern.matchingLogins,
+      [],
+      pattern.formOrigin || "https://mochi.test:8888",
+      {
+        hostname: "mochi.test",
+        generatedPassword: pattern.generatedPassword,
+        willAutoSaveGeneratedPassword: !!pattern.willAutoSaveGeneratedPassword,
+        isSecure: pattern.isSecure,
+        hasBeenTypePassword: pattern.hasBeenTypePassword,
+        telemetryEventData: { searchStartTimeMS: testIndex },
+      }
+    );
+    equal(
+      actual.matchCount,
+      pattern.items.length,
+      `${testIndex}: Check matching row count`
+    );
+    pattern.items.forEach((item, index) => {
+      equal(
+        actual.getValueAt(index),
+        item.value,
+        `${testIndex}: Value ${index}`
+      );
+      equal(
+        actual.getLabelAt(index),
+        item.label,
+        `${testIndex}: Label ${index}`
+      );
+      equal(
+        actual.getStyleAt(index),
+        item.style,
+        `${testIndex}: Style ${index}`
+      );
+      let actualComment = actual.getCommentAt(index);
+      if (typeof item.comment == "object") {
+        let parsedComment = JSON.parse(actualComment);
+        for (let [key, val] of Object.entries(item.comment)) {
+          Assert.deepEqual(
+            parsedComment[key],
+            val,
+            `${testIndex}: Comment.${key} ${index}`
+          );
+        }
+      } else {
+        equal(actualComment, item.comment, `${testIndex}: Comment ${index}`);
+      }
+    });
+
+    if (pattern.items.length) {
+      Assert.throws(
+        () => actual.getValueAt(pattern.items.length),
+        /Index out of range\./
+      );
+
+      Assert.throws(
+        () => actual.getLabelAt(pattern.items.length),
+        /Index out of range\./
+      );
+
+      Assert.throws(
+        () => actual.removeValueAt(pattern.items.length),
+        /Index out of range\./
+      );
+    }
+  });
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_loginsBackup.js b/toolkit/components/passwordmgr/test/unit/test_loginsBackup.js
new file mode 100644
index 0000000000..775f6f5486
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_loginsBackup.js
@@ -0,0 +1,218 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests if logins-backup.json is used correctly in the event that logins.json is missing or corrupt.
+ */
+
+"use strict";
+
+ChromeUtils.defineESModuleGetters(this, {
+  LoginStore: "resource://gre/modules/LoginStore.sys.mjs",
+});
+const { TestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/TestUtils.sys.mjs"
+);
+const { TelemetryTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/TelemetryTestUtils.sys.mjs"
+);
+
+const rawLogin1 = {
+  id: 1,
+  hostname: "http://www.example.com",
+  httpRealm: null,
+  formSubmitURL: "http://www.example.com",
+  usernameField: "field_" + String.fromCharCode(533, 537, 7570, 345),
+  passwordField: "field_" + String.fromCharCode(421, 259, 349, 537),
+  encryptedUsername: "(test)",
+  encryptedPassword: "(test)",
+  guid: "(test)",
+  encType: Ci.nsILoginManagerCrypto.ENCTYPE_SDR,
+  timeCreated: Date.now(),
+  timeLastUsed: Date.now(),
+  timePasswordChanged: Date.now(),
+  timesUsed: 1,
+};
+
+const rawLogin2 = {
+  id: 2,
+  hostname: "http://www.example2.com",
+  httpRealm: null,
+  formSubmitURL: "http://www.example2.com",
+  usernameField: "field_2" + String.fromCharCode(533, 537, 7570, 345),
+  passwordField: "field_2" + String.fromCharCode(421, 259, 349, 537),
+  encryptedUsername: "(test2)",
+  encryptedPassword: "(test2)",
+  guid: "(test2)",
+  encType: Ci.nsILoginManagerCrypto.ENCTYPE_SDR,
+  timeCreated: Date.now(),
+  timeLastUsed: Date.now(),
+  timePasswordChanged: Date.now(),
+  timesUsed: 1,
+};
+
+// Enable the collection (during test) for all products so even products
+// that don't collect the data will be able to run the test without failure.
+Services.prefs.setBoolPref(
+  "toolkit.telemetry.testing.overrideProductsCheck",
+  true
+);
+
+/**
+ * Tests that logins-backup.json can be used by JSONFile.load() when logins.json is missing or cannot be read.
+ */
+add_task(async function test_logins_store_missing_or_corrupt_with_backup() {
+  const loginsStorePath = PathUtils.join(PathUtils.profileDir, "logins.json");
+  const loginsStoreBackup = PathUtils.join(
+    PathUtils.profileDir,
+    "logins-backup.json"
+  );
+
+  // Get store.data ready.
+  let store = new LoginStore(loginsStorePath, loginsStoreBackup);
+  await store.load();
+
+  // Files should not exist at start up.
+  Assert.ok(!(await IOUtils.exists(store.path)), "No store file at start up");
+  Assert.ok(
+    !(await IOUtils.exists(store._options.backupTo)),
+    "No backup file at start up"
+  );
+
+  // Add logins to create logins.json and logins-backup.json.
+  store.data.logins.push(rawLogin1);
+  await store._save();
+  Assert.ok(await IOUtils.exists(store.path));
+
+  store.data.logins.push(rawLogin2);
+  await store._save();
+  Assert.ok(await IOUtils.exists(store._options.backupTo));
+
+  // Remove logins.json and see if logins-backup.json will be used.
+  await IOUtils.remove(store.path);
+  store.data.logins = [];
+  store.dataReady = false;
+  Assert.ok(!(await IOUtils.exists(store.path)));
+  Assert.ok(await IOUtils.exists(store._options.backupTo));
+
+  // Clear any telemetry events recorded in the jsonfile category previously.
+  Services.telemetry.clearEvents();
+
+  await store.load();
+
+  Assert.ok(
+    await IOUtils.exists(store.path),
+    "logins.json is restored as expected after it went missing"
+  );
+
+  Assert.ok(await IOUtils.exists(store._options.backupTo));
+  Assert.equal(
+    store.data.logins.length,
+    1,
+    "Logins backup was used successfully when logins.json was missing"
+  );
+
+  TelemetryTestUtils.assertEvents(
+    [
+      ["jsonfile", "load", "logins"],
+      ["jsonfile", "load", "logins", "used_backup"],
+    ],
+    {},
+    { clear: true }
+  );
+  info(
+    "Telemetry was recorded accurately when logins-backup.json is used when logins.json was missing"
+  );
+
+  // Corrupt the logins.json file.
+  let string = '{"logins":[{"hostname":"http://www.example.com","id":1,';
+  await IOUtils.writeUTF8(store.path, string, {
+    tmpPath: `${store.path}.tmp`,
+  });
+
+  // Clear events recorded in the jsonfile category previously.
+  Services.telemetry.clearEvents();
+
+  // Try to load the corrupt file.
+  store.data.logins = [];
+  store.dataReady = false;
+  await store.load();
+
+  Assert.ok(
+    await IOUtils.exists(`${store.path}.corrupt`),
+    "logins.json.corrupt created"
+  );
+  Assert.ok(
+    await IOUtils.exists(store.path),
+    "logins.json is restored after it was corrupted"
+  );
+
+  // Data should be loaded from logins-backup.json.
+  Assert.ok(await IOUtils.exists(store._options.backupTo));
+  Assert.equal(
+    store.data.logins.length,
+    1,
+    "Logins backup was used successfully when logins.json was corrupt"
+  );
+
+  TelemetryTestUtils.assertEvents(
+    [
+      ["jsonfile", "load", "logins", ""],
+      ["jsonfile", "load", "logins", "invalid_json"],
+      ["jsonfile", "load", "logins", "used_backup"],
+    ],
+    {},
+    { clear: true }
+  );
+  info(
+    "Telemetry was recorded accurately when logins-backup.json is used when logins.json was corrupt"
+  );
+
+  // Clean up before we start the second part of the test.
+  await IOUtils.remove(`${store.path}.corrupt`);
+
+  // Test that the backup file can be used by JSONFile.ensureDataReady() correctly when logins.json is missing.
+  // Remove logins.json
+  await IOUtils.remove(store.path);
+  store.data.logins = [];
+  store.dataReady = false;
+  Assert.ok(!(await IOUtils.exists(store.path)));
+  Assert.ok(await IOUtils.exists(store._options.backupTo));
+
+  store.ensureDataReady();
+
+  // Important to check here if logins.json is restored as expected
+  // after it went missing.
+  await IOUtils.exists(store.path);
+
+  Assert.ok(await IOUtils.exists(store._options.backupTo));
+  await TestUtils.waitForCondition(() => {
+    return store.data.logins.length == 1;
+  });
+
+  // Test that the backup file is used by JSONFile.ensureDataReady() when logins.json is corrupt.
+  // Corrupt the logins.json file.
+  await IOUtils.writeUTF8(store.path, string, {
+    tmpPath: `${store.path}.tmp`,
+  });
+
+  // Try to load the corrupt file.
+  store.data.logins = [];
+  store.dataReady = false;
+  store.ensureDataReady();
+
+  Assert.ok(
+    await IOUtils.exists(`${store.path}.corrupt`),
+    "logins.json.corrupt created"
+  );
+  Assert.ok(
+    await IOUtils.exists(store.path),
+    "logins.json is restored after it was corrupted"
+  );
+
+  // Data should be loaded from logins-backup.json.
+  Assert.ok(await IOUtils.exists(store._options.backupTo));
+  await TestUtils.waitForCondition(() => {
+    return store.data.logins.length == 1;
+  });
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_logins_change.js b/toolkit/components/passwordmgr/test/unit/test_logins_change.js
new file mode 100644
index 0000000000..cc82d6cc0b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_logins_change.js
@@ -0,0 +1,622 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests methods that add, remove, and modify logins.
+ */
+
+"use strict";
+
+// Globals
+
+const MAX_DATE_MS = 8640000000000000;
+
+/**
+ * Verifies that the specified login is considered invalid by addLogin and by
+ * modifyLogin with both nsILoginInfo and nsIPropertyBag arguments.
+ *
+ * This test requires that the login store is empty.
+ *
+ * @param aLoginInfo
+ *        nsILoginInfo corresponding to an invalid login.
+ * @param aExpectedError
+ *        This argument is passed to the "Assert.throws" test to determine which
+ *        error is expected from the modification functions.
+ */
+async function checkLoginInvalid(aLoginInfo, aExpectedError) {
+  // Try to add the new login, and verify that no data is stored.
+  await Assert.rejects(
+    Services.logins.addLoginAsync(aLoginInfo),
+    aExpectedError
+  );
+  await LoginTestUtils.checkLogins([]);
+
+  // Add a login for the modification tests.
+  let testLogin = TestData.formLogin({ origin: "http://modify.example.com" });
+  await Services.logins.addLoginAsync(testLogin);
+
+  // Try to modify the existing login using nsILoginInfo and nsIPropertyBag.
+  Assert.throws(
+    () => Services.logins.modifyLogin(testLogin, aLoginInfo),
+    aExpectedError
+  );
+  Assert.throws(
+    () =>
+      Services.logins.modifyLogin(
+        testLogin,
+        newPropertyBag({
+          origin: aLoginInfo.origin,
+          formActionOrigin: aLoginInfo.formActionOrigin,
+          httpRealm: aLoginInfo.httpRealm,
+          username: aLoginInfo.username,
+          password: aLoginInfo.password,
+          usernameField: aLoginInfo.usernameField,
+          passwordField: aLoginInfo.passwordField,
+        })
+      ),
+    aExpectedError
+  );
+
+  // Verify that no data was stored by the previous calls.
+  await LoginTestUtils.checkLogins([testLogin]);
+  Services.logins.removeLogin(testLogin);
+}
+
+/**
+ * Verifies that two objects are not the same instance
+ * but have equal attributes.
+ *
+ * @param {Object} objectA
+ *        An object to compare.
+ *
+ * @param {Object} objectB
+ *        Another object to compare.
+ *
+ * @param {string[]} attributes
+ *        Attributes to compare.
+ *
+ * @return true if all passed attributes are equal for both objects, false otherwise.
+ */
+function compareAttributes(objectA, objectB, attributes) {
+  // If it's the same object, we want to return false.
+  if (objectA == objectB) {
+    return false;
+  }
+  return attributes.every(attr => objectA[attr] == objectB[attr]);
+}
+
+// Tests
+
+/**
+ * Tests that adding logins to the database works.
+ */
+add_task(async function test_addLogin_removeLogin() {
+  // Each login from the test data should be valid and added to the list.
+  await Services.logins.addLogins(TestData.loginList());
+  await LoginTestUtils.checkLogins(TestData.loginList());
+
+  // Trying to add each login again should result in an error.
+  for (let loginInfo of TestData.loginList()) {
+    await Assert.rejects(
+      Services.logins.addLoginAsync(loginInfo),
+      /This login already exists./
+    );
+  }
+
+  // Removing each login should succeed.
+  for (let loginInfo of TestData.loginList()) {
+    Services.logins.removeLogin(loginInfo);
+  }
+
+  await LoginTestUtils.checkLogins([]);
+});
+
+add_task(async function add_login_works_with_empty_array() {
+  const result = await Services.logins.addLogins([]);
+  Assert.equal(result.length, 0, "no logins added");
+});
+
+add_task(async function duplicated_logins_are_not_added() {
+  const login = TestData.formLogin({
+    username: "user",
+  });
+  await Services.logins.addLogins([login]);
+  const result = await Services.logins.addLogins([login]);
+  Assert.equal(result, 0, "no logins added");
+  Services.logins.removeAllUserFacingLogins();
+});
+
+add_task(async function logins_containing_nul_in_username_are_not_added() {
+  const result = await Services.logins.addLogins([
+    TestData.formLogin({ username: "user\0name" }),
+  ]);
+  Assert.equal(result, 0, "no logins added");
+});
+
+add_task(async function logins_containing_nul_in_password_are_not_added() {
+  const result = await Services.logins.addLogins([
+    TestData.formLogin({ password: "pass\0word" }),
+  ]);
+  Assert.equal(result, 0, "no logins added");
+});
+
+add_task(
+  async function return_value_includes_plaintext_username_and_password() {
+    const login = TestData.formLogin({});
+    const [result] = await Services.logins.addLogins([login]);
+    Assert.equal(result.username, login.username, "plaintext username is set");
+    Assert.equal(result.password, login.password, "plaintext password is set");
+    Services.logins.removeAllUserFacingLogins();
+  }
+);
+
+add_task(async function event_data_includes_plaintext_username_and_password() {
+  const login = TestData.formLogin({});
+  const TestObserver = {
+    QueryInterface: ChromeUtils.generateQI([
+      "nsIObserver",
+      "nsISupportsWeakReference",
+    ]),
+    observe(subject, topic, data) {
+      Assert.ok(subject instanceof Ci.nsILoginInfo);
+      Assert.ok(subject instanceof Ci.nsILoginMetaInfo);
+      Assert.equal(
+        subject.username,
+        login.username,
+        "plaintext username is set"
+      );
+      Assert.equal(
+        subject.password,
+        login.password,
+        "plaintext password is set"
+      );
+    },
+  };
+  Services.obs.addObserver(TestObserver, "passwordmgr-storage-changed");
+  await Services.logins.addLogins([login]);
+  Services.obs.removeObserver(TestObserver, "passwordmgr-storage-changed");
+  Services.logins.removeAllUserFacingLogins();
+});
+
+/**
+ * Tests invalid combinations of httpRealm and formActionOrigin.
+ *
+ * For an nsILoginInfo to be valid for storage, one of the two properties should
+ * be strictly equal to null, and the other must not be null.
+ *
+ * The legacy case of an empty string in formActionOrigin and a null value in
+ * httpRealm is also supported for storage at the moment.
+ */
+add_task(async function test_invalid_httpRealm_formActionOrigin() {
+  // httpRealm === null, formActionOrigin === null
+  await checkLoginInvalid(
+    TestData.formLogin({ formActionOrigin: null }),
+    /without a httpRealm or formActionOrigin/
+  );
+
+  // httpRealm === null, formActionOrigin === ""
+  // TODO: This is not enforced for now.
+  // await checkLoginInvalid(TestData.formLogin({ formActionOrigin: "" }),
+  //                   /without a httpRealm or formActionOrigin/);
+
+  // httpRealm === "", formActionOrigin === ""
+  let login = TestData.formLogin({ formActionOrigin: "" });
+  login.httpRealm = "";
+  await checkLoginInvalid(login, /both a httpRealm and formActionOrigin/);
+
+  // !!httpRealm, !!formActionOrigin
+  login = TestData.formLogin();
+  login.httpRealm = "The HTTP Realm";
+  await checkLoginInvalid(login, /both a httpRealm and formActionOrigin/);
+
+  // httpRealm === "", !!formActionOrigin
+  login = TestData.formLogin();
+  login.httpRealm = "";
+  await checkLoginInvalid(login, /both a httpRealm and formActionOrigin/);
+
+  // !!httpRealm, formActionOrigin === ""
+  login = TestData.authLogin();
+  login.formActionOrigin = "";
+  await checkLoginInvalid(login, /both a httpRealm and formActionOrigin/);
+});
+
+/**
+ * Tests null or empty values in required login properties.
+ */
+add_task(async function test_missing_properties() {
+  await checkLoginInvalid(
+    TestData.formLogin({ origin: null }),
+    /null or empty origin/
+  );
+
+  await checkLoginInvalid(
+    TestData.formLogin({ origin: "" }),
+    /null or empty origin/
+  );
+
+  await checkLoginInvalid(
+    TestData.formLogin({ username: null }),
+    /null username/
+  );
+
+  await checkLoginInvalid(
+    TestData.formLogin({ password: null }),
+    /null or empty password/
+  );
+
+  await checkLoginInvalid(
+    TestData.formLogin({ password: "" }),
+    /null or empty password/
+  );
+});
+
+/**
+ * Tests invalid NUL characters in nsILoginInfo properties.
+ */
+add_task(async function test_invalid_characters() {
+  let loginList = [
+    TestData.authLogin({ origin: "http://null\0X.example.com" }),
+    TestData.authLogin({ httpRealm: "realm\0" }),
+    TestData.formLogin({ formActionOrigin: "http://null\0X.example.com" }),
+    TestData.formLogin({ usernameField: "field\0_null" }),
+    TestData.formLogin({ usernameField: ".\0" }), // Special single dot case
+    TestData.formLogin({ passwordField: "field\0_null" }),
+    TestData.formLogin({ username: "user\0name" }),
+    TestData.formLogin({ password: "pass\0word" }),
+  ];
+  for (let loginInfo of loginList) {
+    await checkLoginInvalid(loginInfo, /login values can't contain nulls/);
+  }
+});
+
+/**
+ * Tests removing a login that does not exists.
+ */
+add_task(function test_removeLogin_nonexisting() {
+  Assert.throws(
+    () => Services.logins.removeLogin(TestData.formLogin()),
+    /No matching logins/
+  );
+});
+
+/**
+ * Tests removing all logins at once.
+ */
+add_task(async function test_removeAllUserFacingLogins() {
+  await Services.logins.addLogins(TestData.loginList());
+
+  Services.logins.removeAllUserFacingLogins();
+  await LoginTestUtils.checkLogins([]);
+
+  // The function should also work when there are no logins to delete.
+  Services.logins.removeAllUserFacingLogins();
+});
+
+/**
+ * Tests the modifyLogin function with an nsILoginInfo argument.
+ */
+add_task(async function test_modifyLogin_nsILoginInfo() {
+  let loginInfo = TestData.formLogin();
+  let updatedLoginInfo = TestData.formLogin({
+    username: "new username",
+    password: "new password",
+    usernameField: "new_form_field_username",
+    passwordField: "new_form_field_password",
+  });
+  let differentLoginInfo = TestData.authLogin();
+
+  // Trying to modify a login that does not exist should throw.
+  Assert.throws(
+    () => Services.logins.modifyLogin(loginInfo, updatedLoginInfo),
+    /No matching logins/
+  );
+
+  // Add the first form login, then modify it to match the second.
+  await Services.logins.addLoginAsync(loginInfo);
+  Services.logins.modifyLogin(loginInfo, updatedLoginInfo);
+
+  // The data should now match the second login.
+  await LoginTestUtils.checkLogins([updatedLoginInfo]);
+  Assert.throws(
+    () => Services.logins.modifyLogin(loginInfo, updatedLoginInfo),
+    /No matching logins/
+  );
+
+  // The login can be changed to have a different type and origin.
+  Services.logins.modifyLogin(updatedLoginInfo, differentLoginInfo);
+  await LoginTestUtils.checkLogins([differentLoginInfo]);
+
+  // It is now possible to add a login with the old type and origin.
+  await Services.logins.addLoginAsync(loginInfo);
+  await LoginTestUtils.checkLogins([loginInfo, differentLoginInfo]);
+
+  // Modifying a login to match an existing one should not be possible.
+  Assert.throws(
+    () => Services.logins.modifyLogin(loginInfo, differentLoginInfo),
+    /already exists/
+  );
+  await LoginTestUtils.checkLogins([loginInfo, differentLoginInfo]);
+
+  LoginTestUtils.clearData();
+});
+
+/**
+ * Tests the modifyLogin function with an nsIPropertyBag argument.
+ */
+add_task(async function test_modifyLogin_nsIProperyBag() {
+  let loginInfo = TestData.formLogin();
+  let updatedLoginInfo = TestData.formLogin({
+    username: "new username",
+    password: "new password",
+    usernameField: "",
+    passwordField: "new_form_field_password",
+  });
+  let differentLoginInfo = TestData.authLogin();
+  let differentLoginProperties = newPropertyBag({
+    origin: differentLoginInfo.origin,
+    formActionOrigin: differentLoginInfo.formActionOrigin,
+    httpRealm: differentLoginInfo.httpRealm,
+    username: differentLoginInfo.username,
+    password: differentLoginInfo.password,
+    usernameField: differentLoginInfo.usernameField,
+    passwordField: differentLoginInfo.passwordField,
+  });
+
+  // Trying to modify a login that does not exist should throw.
+  Assert.throws(
+    () => Services.logins.modifyLogin(loginInfo, newPropertyBag()),
+    /No matching logins/
+  );
+
+  // Add the first form login, then modify it to match the second, changing
+  // only some of its properties and checking the behavior with an empty string.
+  await Services.logins.addLoginAsync(loginInfo);
+  Services.logins.modifyLogin(
+    loginInfo,
+    newPropertyBag({
+      username: "new username",
+      password: "new password",
+      usernameField: "",
+      passwordField: "new_form_field_password",
+    })
+  );
+
+  // The data should now match the second login.
+  await LoginTestUtils.checkLogins([updatedLoginInfo]);
+  Assert.throws(
+    () => Services.logins.modifyLogin(loginInfo, newPropertyBag()),
+    /No matching logins/
+  );
+
+  // It is also possible to provide no properties to be modified.
+  Services.logins.modifyLogin(updatedLoginInfo, newPropertyBag());
+
+  // Specifying a null property for a required value should throw.
+  Assert.throws(
+    () =>
+      Services.logins.modifyLogin(
+        loginInfo,
+        newPropertyBag({
+          usernameField: null,
+        })
+      ),
+    /No matching logins/
+  );
+
+  // The login can be changed to have a different type and origin.
+  Services.logins.modifyLogin(updatedLoginInfo, differentLoginProperties);
+  await LoginTestUtils.checkLogins([differentLoginInfo]);
+
+  // It is now possible to add a login with the old type and origin.
+  await Services.logins.addLoginAsync(loginInfo);
+  await LoginTestUtils.checkLogins([loginInfo, differentLoginInfo]);
+
+  // Modifying a login to match an existing one should not be possible.
+  Assert.throws(
+    () => Services.logins.modifyLogin(loginInfo, differentLoginProperties),
+    /already exists/
+  );
+  await LoginTestUtils.checkLogins([loginInfo, differentLoginInfo]);
+
+  LoginTestUtils.clearData();
+});
+
+/**
+ * Tests the login deduplication function.
+ */
+add_task(function test_deduplicate_logins() {
+  // Different key attributes combinations and the amount of unique
+  // results expected for the TestData login list.
+  let keyCombinations = [
+    {
+      keyset: ["username", "password"],
+      results: 17,
+    },
+    {
+      keyset: ["origin", "username"],
+      results: 21,
+    },
+    {
+      keyset: ["origin", "username", "password"],
+      results: 22,
+    },
+    {
+      keyset: ["origin", "username", "password", "formActionOrigin"],
+      results: 27,
+    },
+  ];
+
+  let logins = TestData.loginList();
+
+  for (let testCase of keyCombinations) {
+    // Deduplicate the logins using the current testcase keyset.
+    let deduped = LoginHelper.dedupeLogins(logins, testCase.keyset);
+    Assert.equal(
+      deduped.length,
+      testCase.results,
+      "Correct amount of results."
+    );
+
+    // Checks that every login after deduping is unique.
+    Assert.ok(
+      deduped.every(loginA =>
+        deduped.every(
+          loginB => !compareAttributes(loginA, loginB, testCase.keyset)
+        )
+      ),
+      "Every login is unique."
+    );
+  }
+});
+
+/**
+ * Ensure that the login deduplication function keeps the most recent login.
+ */
+add_task(function test_deduplicate_keeps_most_recent() {
+  // Logins to deduplicate.
+  let logins = [
+    TestData.formLogin({ timeLastUsed: Date.UTC(2004, 11, 4, 0, 0, 0) }),
+    TestData.formLogin({
+      formActionOrigin: "http://example.com",
+      timeLastUsed: Date.UTC(2015, 11, 4, 0, 0, 0),
+    }),
+  ];
+
+  // Deduplicate the logins.
+  let deduped = LoginHelper.dedupeLogins(logins);
+  Assert.equal(deduped.length, 1, "Deduplicated the logins array.");
+
+  // Verify that the remaining login have the most recent date.
+  let loginTimeLastUsed = deduped[0].QueryInterface(
+    Ci.nsILoginMetaInfo
+  ).timeLastUsed;
+  Assert.equal(
+    loginTimeLastUsed,
+    Date.UTC(2015, 11, 4, 0, 0, 0),
+    "Most recent login was kept."
+  );
+
+  // Deduplicate the reverse logins array.
+  deduped = LoginHelper.dedupeLogins(logins.reverse());
+  Assert.equal(deduped.length, 1, "Deduplicated the reversed logins array.");
+
+  // Verify that the remaining login have the most recent date.
+  loginTimeLastUsed = deduped[0].QueryInterface(
+    Ci.nsILoginMetaInfo
+  ).timeLastUsed;
+  Assert.equal(
+    loginTimeLastUsed,
+    Date.UTC(2015, 11, 4, 0, 0, 0),
+    "Most recent login was kept."
+  );
+});
+
+/**
+ * Tests handling when adding a login with bad date values
+ */
+add_task(async function test_addLogin_badDates() {
+  LoginTestUtils.clearData();
+
+  let now = Date.now();
+  let defaultLoginDates = {
+    timeCreated: now,
+    timeLastUsed: now,
+    timePasswordChanged: now,
+  };
+
+  let defaultsLogin = TestData.formLogin();
+  for (let pname of ["timeCreated", "timeLastUsed", "timePasswordChanged"]) {
+    Assert.ok(!defaultsLogin[pname]);
+  }
+  Assert.ok(
+    !!(await Services.logins.addLoginAsync(defaultsLogin)),
+    "Sanity check adding defaults formLogin"
+  );
+  Services.logins.removeAllUserFacingLogins();
+
+  // 0 is a valid date in this context - new nsLoginInfo timestamps init to 0
+  for (let pname of ["timeCreated", "timeLastUsed", "timePasswordChanged"]) {
+    let loginInfo = TestData.formLogin(
+      Object.assign({}, defaultLoginDates, {
+        [pname]: 0,
+      })
+    );
+    Assert.ok(
+      !!(await Services.logins.addLoginAsync(loginInfo)),
+      "Check 0 value for " + pname
+    );
+    Services.logins.removeAllUserFacingLogins();
+  }
+
+  // negative dates get clamped to 0 and are ok
+  for (let pname of ["timeCreated", "timeLastUsed", "timePasswordChanged"]) {
+    let loginInfo = TestData.formLogin(
+      Object.assign({}, defaultLoginDates, {
+        [pname]: -1,
+      })
+    );
+    Assert.ok(
+      !!(await Services.logins.addLoginAsync(loginInfo)),
+      "Check -1 value for " + pname
+    );
+    Services.logins.removeAllUserFacingLogins();
+  }
+
+  // out-of-range dates will throw
+  for (let pname of ["timeCreated", "timeLastUsed", "timePasswordChanged"]) {
+    let loginInfo = TestData.formLogin(
+      Object.assign({}, defaultLoginDates, {
+        [pname]: MAX_DATE_MS + 1,
+      })
+    );
+    await Assert.rejects(
+      Services.logins.addLoginAsync(loginInfo),
+      /invalid date properties/
+    );
+    Assert.equal((await Services.logins.getAllLogins()).length, 0);
+  }
+
+  await LoginTestUtils.checkLogins([]);
+});
+
+/**
+ * Tests handling when adding multiple logins with bad date values
+ */
+add_task(async function test_addLogins_badDates() {
+  LoginTestUtils.clearData();
+
+  let defaultsLogin = TestData.formLogin({
+    username: "defaults",
+  });
+  await Services.logins.addLoginAsync(defaultsLogin);
+
+  // -11644473600000 is the value you get if you convert Dec 31 1600 16:07:02 to unix epoch time
+  let timeCreatedLogin = TestData.formLogin({
+    username: "tc",
+    timeCreated: -11644473600000,
+  });
+  await Assert.rejects(
+    Services.logins.addLoginAsync(timeCreatedLogin),
+    /Can\'t add a login with invalid date properties./
+  );
+
+  let timeLastUsedLogin = TestData.formLogin({
+    username: "tlu",
+    timeLastUsed: -11644473600000,
+  });
+  await Assert.rejects(
+    Services.logins.addLoginAsync(timeLastUsedLogin),
+    /Can\'t add a login with invalid date properties./
+  );
+
+  let timePasswordChangedLogin = TestData.formLogin({
+    username: "tpc",
+    timePasswordChanged: -11644473600000,
+  });
+  await Assert.rejects(
+    Services.logins.addLoginAsync(timePasswordChangedLogin),
+    /Can\'t add a login with invalid date properties./
+  );
+
+  Services.logins.removeAllUserFacingLogins();
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_logins_decrypt_failure.js b/toolkit/components/passwordmgr/test/unit/test_logins_decrypt_failure.js
new file mode 100644
index 0000000000..533bd9dd8d
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_logins_decrypt_failure.js
@@ -0,0 +1,172 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests the case where there are logins that cannot be decrypted.
+ */
+
+"use strict";
+
+// Globals
+
+/**
+ * Resets the token used to decrypt logins.  This is equivalent to resetting the
+ * primary password when it is not known.
+ */
+function resetPrimaryPassword() {
+  let token = Cc["@mozilla.org/security/pk11tokendb;1"]
+    .getService(Ci.nsIPK11TokenDB)
+    .getInternalKeyToken();
+  token.reset();
+  token.initPassword("");
+}
+
+// Tests
+
+/**
+ * Resets the primary password after some logins were added to the database.
+ */
+add_task(async function test_logins_decrypt_failure() {
+  let logins = TestData.loginList();
+  await Services.logins.addLogins(logins);
+
+  // This makes the existing logins non-decryptable.
+  resetPrimaryPassword();
+
+  // These functions don't see the non-decryptable entries anymore.
+  let savedLogins = await Services.logins.getAllLogins();
+  Assert.equal(savedLogins.length, 0, "getAllLogins length");
+  await Assert.rejects(Services.logins.searchLoginsAsync({}), /is required/);
+  Assert.equal(Services.logins.searchLogins(newPropertyBag()).length, 0);
+  Assert.throws(
+    () => Services.logins.modifyLogin(logins[0], newPropertyBag()),
+    /No matching logins/
+  );
+  Assert.throws(
+    () => Services.logins.removeLogin(logins[0]),
+    /No matching logins/
+  );
+
+  // The function that counts logins sees the non-decryptable entries also.
+  Assert.equal(Services.logins.countLogins("", "", ""), logins.length);
+
+  // Equivalent logins can be added.
+  await Services.logins.addLogins(logins);
+  await LoginTestUtils.checkLogins(logins);
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    logins.length,
+    "getAllLogins length"
+  );
+  Assert.equal(Services.logins.countLogins("", "", ""), logins.length * 2);
+
+  // Finding logins doesn't return the non-decryptable duplicates.
+  Assert.equal(
+    (
+      await Services.logins.searchLoginsAsync({
+        origin: "http://www.example.com",
+      })
+    ).length,
+    1
+  );
+  let matchData = newPropertyBag({ origin: "http://www.example.com" });
+  Assert.equal(Services.logins.searchLogins(matchData).length, 1);
+
+  // Removing single logins does not remove non-decryptable logins.
+  for (let loginInfo of TestData.loginList()) {
+    Services.logins.removeLogin(loginInfo);
+  }
+  Assert.equal((await Services.logins.getAllLogins()).length, 0);
+  Assert.equal(Services.logins.countLogins("", "", ""), logins.length);
+
+  // Removing all logins removes the non-decryptable entries also.
+  Services.logins.removeAllUserFacingLogins();
+  Assert.equal((await Services.logins.getAllLogins()).length, 0);
+  Assert.equal(Services.logins.countLogins("", "", ""), 0);
+});
+
+// Bug 621846 - If a login has a GUID but can't be decrypted, a search for
+// that GUID will (correctly) fail. Ensure we can add a new login with that
+// same GUID.
+add_task(async function test_add_logins_with_decrypt_failure() {
+  // a login with a GUID.
+  let login = new LoginInfo(
+    "http://www.example2.com",
+    "http://www.example2.com",
+    null,
+    "the username",
+    "the password for www.example.com",
+    "form_field_username",
+    "form_field_password"
+  );
+
+  login.QueryInterface(Ci.nsILoginMetaInfo);
+  login.guid = "{4bc50d2f-dbb6-4aa3-807c-c4c2065a2c35}";
+
+  // A different login but with the same GUID.
+  let loginDupeGuid = new LoginInfo(
+    "http://www.example3.com",
+    "http://www.example3.com",
+    null,
+    "the username",
+    "the password",
+    "form_field_username",
+    "form_field_password"
+  );
+  loginDupeGuid.QueryInterface(Ci.nsILoginMetaInfo);
+  loginDupeGuid.guid = login.guid;
+
+  await Services.logins.addLoginAsync(login);
+
+  // We can search for this login by GUID.
+  let searchProp = Cc["@mozilla.org/hash-property-bag;1"].createInstance(
+    Ci.nsIWritablePropertyBag2
+  );
+  searchProp.setPropertyAsAUTF8String("guid", login.guid);
+
+  equal(Services.logins.searchLogins(searchProp).length, 1);
+
+  // We should fail to re-add it as it remains good.
+  await Assert.rejects(
+    Services.logins.addLoginAsync(login),
+    /This login already exists./
+  );
+  // We should fail to re-add a different login with the same GUID.
+  await Assert.rejects(
+    Services.logins.addLoginAsync(loginDupeGuid),
+    /specified GUID already exists/
+  );
+
+  // This makes the existing login non-decryptable.
+  resetPrimaryPassword();
+
+  // We can no longer find it in our search.
+  equal(Services.logins.searchLogins(searchProp).length, 0);
+
+  // So we should be able to re-add a login with that same GUID.
+  await Services.logins.addLoginAsync(login);
+  equal(Services.logins.searchLogins(searchProp).length, 1);
+
+  Services.logins.removeAllUserFacingLogins();
+});
+
+// Test the "syncID" metadata works as expected on decryption failure.
+add_task(async function test_sync_metadata_with_decrypt_failure() {
+  // And some sync metadata
+  await Services.logins.setSyncID("sync-id");
+  await Services.logins.setLastSync(123);
+  equal(await Services.logins.getSyncID(), "sync-id");
+  equal(await Services.logins.getLastSync(), 123);
+
+  // This makes the existing login and syncID non-decryptable.
+  resetPrimaryPassword();
+
+  // The syncID is now null.
+  equal(await Services.logins.getSyncID(), null);
+  // The sync timestamp isn't impacted.
+  equal(await Services.logins.getLastSync(), 123);
+
+  // But we should be able to set it again.
+  await Services.logins.setSyncID("new-id");
+  equal(await Services.logins.getSyncID(), "new-id");
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_logins_metainfo.js b/toolkit/components/passwordmgr/test/unit/test_logins_metainfo.js
new file mode 100644
index 0000000000..e851564981
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_logins_metainfo.js
@@ -0,0 +1,304 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests the handling of nsILoginMetaInfo by methods that add, remove, modify,
+ * and find logins.
+ */
+
+"use strict";
+
+// Globals
+
+const gLooksLikeUUIDRegex = /^\{\w{8}-\w{4}-\w{4}-\w{4}-\w{12}\}$/;
+
+/**
+ * Retrieves the only login among the current data that matches the origin of
+ * the given nsILoginInfo.  In case there is more than one login for the
+ * origin, the test fails.
+ */
+async function retrieveOriginMatching(origin) {
+  let logins = await Services.logins.searchLoginsAsync({ origin });
+  Assert.equal(logins.length, 1);
+  return logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+}
+
+/**
+ * Checks that the nsILoginInfo and nsILoginMetaInfo properties of two different
+ * login instances are equal.
+ */
+function assertMetaInfoEqual(aActual, aExpected) {
+  Assert.notEqual(aActual, aExpected);
+
+  // Check the nsILoginInfo properties.
+  Assert.ok(aActual.equals(aExpected));
+
+  // Check the nsILoginMetaInfo properties.
+  Assert.equal(aActual.guid, aExpected.guid);
+  Assert.equal(aActual.timeCreated, aExpected.timeCreated);
+  Assert.equal(aActual.timeLastUsed, aExpected.timeLastUsed);
+  Assert.equal(aActual.timePasswordChanged, aExpected.timePasswordChanged);
+  Assert.equal(aActual.timesUsed, aExpected.timesUsed);
+}
+
+/**
+ * nsILoginInfo instances with or without nsILoginMetaInfo properties.
+ */
+let gLoginInfo1;
+let gLoginInfo2;
+let gLoginInfo3;
+
+/**
+ * nsILoginInfo instances reloaded with all the nsILoginMetaInfo properties.
+ * These are often used to provide the reference values to test against.
+ */
+let gLoginMetaInfo1;
+let gLoginMetaInfo2;
+let gLoginMetaInfo3;
+
+// Tests
+
+/**
+ * Prepare the test objects that will be used by the following tests.
+ */
+add_task(function test_initialize() {
+  // Use a reference time from ten minutes ago to initialize one instance of
+  // nsILoginMetaInfo, to test that reference times are updated when needed.
+  let baseTimeMs = Date.now() - 600000;
+
+  gLoginInfo1 = TestData.formLogin();
+  gLoginInfo2 = TestData.formLogin({
+    origin: "http://other.example.com",
+    guid: Services.uuid.generateUUID().toString(),
+    timeCreated: baseTimeMs,
+    timeLastUsed: baseTimeMs + 2,
+    timePasswordChanged: baseTimeMs + 1,
+    timesUsed: 2,
+  });
+  gLoginInfo3 = TestData.authLogin();
+});
+
+/**
+ * Tests the behavior of addLogin with regard to metadata.  The logins added
+ * here are also used by the following tests.
+ */
+add_task(async function test_addLogin_metainfo() {
+  // Add a login without metadata to the database.
+  await Services.logins.addLoginAsync(gLoginInfo1);
+
+  // The object provided to addLogin should not have been modified.
+  Assert.equal(gLoginInfo1.guid, null);
+  Assert.equal(gLoginInfo1.timeCreated, 0);
+  Assert.equal(gLoginInfo1.timeLastUsed, 0);
+  Assert.equal(gLoginInfo1.timePasswordChanged, 0);
+  Assert.equal(gLoginInfo1.timesUsed, 0);
+
+  // A login with valid metadata should have been stored.
+  gLoginMetaInfo1 = await retrieveOriginMatching(gLoginInfo1.origin);
+  Assert.ok(gLooksLikeUUIDRegex.test(gLoginMetaInfo1.guid));
+  let creationTime = gLoginMetaInfo1.timeCreated;
+  LoginTestUtils.assertTimeIsAboutNow(creationTime);
+  Assert.equal(gLoginMetaInfo1.timeLastUsed, creationTime);
+  Assert.equal(gLoginMetaInfo1.timePasswordChanged, creationTime);
+  Assert.equal(gLoginMetaInfo1.timesUsed, 1);
+
+  // Add a login without metadata to the database.
+  let originalLogin = gLoginInfo2.clone().QueryInterface(Ci.nsILoginMetaInfo);
+  await Services.logins.addLoginAsync(gLoginInfo2);
+
+  // The object provided to addLogin should not have been modified.
+  assertMetaInfoEqual(gLoginInfo2, originalLogin);
+
+  // A login with the provided metadata should have been stored.
+  gLoginMetaInfo2 = await retrieveOriginMatching(gLoginInfo2.origin);
+  assertMetaInfoEqual(gLoginMetaInfo2, gLoginInfo2);
+
+  // Add an authentication login to the database before continuing.
+  await Services.logins.addLoginAsync(gLoginInfo3);
+  gLoginMetaInfo3 = await retrieveOriginMatching(gLoginInfo3.origin);
+  await LoginTestUtils.checkLogins([gLoginInfo1, gLoginInfo2, gLoginInfo3]);
+});
+
+/**
+ * Tests that adding a login with a duplicate GUID throws an exception.
+ */
+add_task(async function test_addLogin_metainfo_duplicate() {
+  let loginInfo = TestData.formLogin({
+    origin: "http://duplicate.example.com",
+    guid: gLoginMetaInfo2.guid,
+  });
+  await Assert.rejects(
+    Services.logins.addLoginAsync(loginInfo),
+    /specified GUID already exists/
+  );
+
+  // Verify that no data was stored by the previous call.
+  await LoginTestUtils.checkLogins([gLoginInfo1, gLoginInfo2, gLoginInfo3]);
+});
+
+/**
+ * Tests that the existing metadata is not changed when modifyLogin is called
+ * with an nsILoginInfo argument.
+ */
+add_task(async function test_modifyLogin_nsILoginInfo_metainfo_ignored() {
+  let newLoginInfo = gLoginInfo1.clone().QueryInterface(Ci.nsILoginMetaInfo);
+  newLoginInfo.guid = Services.uuid.generateUUID().toString();
+  newLoginInfo.timeCreated = Date.now();
+  newLoginInfo.timeLastUsed = Date.now();
+  newLoginInfo.timePasswordChanged = Date.now();
+  newLoginInfo.timesUsed = 12;
+  Services.logins.modifyLogin(gLoginInfo1, newLoginInfo);
+
+  newLoginInfo = await retrieveOriginMatching(gLoginInfo1.origin);
+  assertMetaInfoEqual(newLoginInfo, gLoginMetaInfo1);
+});
+
+/**
+ * Tests the modifyLogin function with an nsIProperyBag argument.
+ */
+add_task(async function test_modifyLogin_nsIProperyBag_metainfo() {
+  // Use a new reference time that is two minutes from now.
+  let newTimeMs = Date.now() + 120000;
+  let newUUIDValue = Services.uuid.generateUUID().toString();
+
+  // Check that properties are changed as requested.
+  Services.logins.modifyLogin(
+    gLoginInfo1,
+    newPropertyBag({
+      guid: newUUIDValue,
+      timeCreated: newTimeMs,
+      timeLastUsed: newTimeMs + 2,
+      timePasswordChanged: newTimeMs + 1,
+      timesUsed: 2,
+    })
+  );
+
+  gLoginMetaInfo1 = await retrieveOriginMatching(gLoginInfo1.origin);
+  Assert.equal(gLoginMetaInfo1.guid, newUUIDValue);
+  Assert.equal(gLoginMetaInfo1.timeCreated, newTimeMs);
+  Assert.equal(gLoginMetaInfo1.timeLastUsed, newTimeMs + 2);
+  Assert.equal(gLoginMetaInfo1.timePasswordChanged, newTimeMs + 1);
+  Assert.equal(gLoginMetaInfo1.timesUsed, 2);
+
+  // Check that timePasswordChanged is updated when changing the password.
+  let originalLogin = gLoginInfo2.clone().QueryInterface(Ci.nsILoginMetaInfo);
+  Services.logins.modifyLogin(
+    gLoginInfo2,
+    newPropertyBag({
+      password: "new password",
+    })
+  );
+  gLoginInfo2.password = "new password";
+
+  gLoginMetaInfo2 = await retrieveOriginMatching(gLoginInfo2.origin);
+  Assert.equal(gLoginMetaInfo2.password, gLoginInfo2.password);
+  Assert.equal(gLoginMetaInfo2.timeCreated, originalLogin.timeCreated);
+  Assert.equal(gLoginMetaInfo2.timeLastUsed, originalLogin.timeLastUsed);
+  LoginTestUtils.assertTimeIsAboutNow(gLoginMetaInfo2.timePasswordChanged);
+
+  // Check that timePasswordChanged is not set to the current time when changing
+  // the password and specifying a new value for the property at the same time.
+  Services.logins.modifyLogin(
+    gLoginInfo2,
+    newPropertyBag({
+      password: "other password",
+      timePasswordChanged: newTimeMs,
+    })
+  );
+  gLoginInfo2.password = "other password";
+
+  gLoginMetaInfo2 = await retrieveOriginMatching(gLoginInfo2.origin);
+  Assert.equal(gLoginMetaInfo2.password, gLoginInfo2.password);
+  Assert.equal(gLoginMetaInfo2.timeCreated, originalLogin.timeCreated);
+  Assert.equal(gLoginMetaInfo2.timeLastUsed, originalLogin.timeLastUsed);
+  Assert.equal(gLoginMetaInfo2.timePasswordChanged, newTimeMs);
+
+  // Check the special timesUsedIncrement property.
+  Services.logins.modifyLogin(
+    gLoginInfo2,
+    newPropertyBag({
+      timesUsedIncrement: 2,
+    })
+  );
+
+  gLoginMetaInfo2 = await retrieveOriginMatching(gLoginInfo2.origin);
+  Assert.equal(gLoginMetaInfo2.timeCreated, originalLogin.timeCreated);
+  Assert.equal(gLoginMetaInfo2.timeLastUsed, originalLogin.timeLastUsed);
+  Assert.equal(gLoginMetaInfo2.timePasswordChanged, newTimeMs);
+  Assert.equal(gLoginMetaInfo2.timesUsed, 4);
+});
+
+/**
+ * Tests that modifying a login to a duplicate GUID throws an exception.
+ */
+add_task(async function test_modifyLogin_nsIProperyBag_metainfo_duplicate() {
+  Assert.throws(
+    () =>
+      Services.logins.modifyLogin(
+        gLoginInfo1,
+        newPropertyBag({
+          guid: gLoginInfo2.guid,
+        })
+      ),
+    /specified GUID already exists/
+  );
+  await LoginTestUtils.checkLogins([gLoginInfo1, gLoginInfo2, gLoginInfo3]);
+});
+
+/**
+ * Tests searching logins using nsILoginMetaInfo properties.
+ */
+add_task(function test_searchLogins_metainfo() {
+  // Find by GUID.
+  let logins = Services.logins.searchLogins(
+    newPropertyBag({
+      guid: gLoginMetaInfo1.guid,
+    })
+  );
+  Assert.equal(logins.length, 1);
+  let foundLogin = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  assertMetaInfoEqual(foundLogin, gLoginMetaInfo1);
+
+  // Find by timestamp.
+  logins = Services.logins.searchLogins(
+    newPropertyBag({
+      timePasswordChanged: gLoginMetaInfo2.timePasswordChanged,
+    })
+  );
+  Assert.equal(logins.length, 1);
+  foundLogin = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  assertMetaInfoEqual(foundLogin, gLoginMetaInfo2);
+
+  // Find using two properties at the same time.
+  logins = Services.logins.searchLogins(
+    newPropertyBag({
+      guid: gLoginMetaInfo3.guid,
+      timePasswordChanged: gLoginMetaInfo3.timePasswordChanged,
+    })
+  );
+  Assert.equal(logins.length, 1);
+  foundLogin = logins[0].QueryInterface(Ci.nsILoginMetaInfo);
+  assertMetaInfoEqual(foundLogin, gLoginMetaInfo3);
+});
+
+/**
+ * Tests that the default storage module attached to the Login
+ * Manager service is able to save and reload nsILoginMetaInfo properties.
+ */
+add_task(async function test_storage_metainfo() {
+  await LoginTestUtils.reloadData();
+  await LoginTestUtils.checkLogins([gLoginInfo1, gLoginInfo2, gLoginInfo3]);
+
+  assertMetaInfoEqual(
+    await retrieveOriginMatching(gLoginInfo1.origin),
+    gLoginMetaInfo1
+  );
+  assertMetaInfoEqual(
+    await retrieveOriginMatching(gLoginInfo2.origin),
+    gLoginMetaInfo2
+  );
+  assertMetaInfoEqual(
+    await retrieveOriginMatching(gLoginInfo3.origin),
+    gLoginMetaInfo3
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_logins_search.js b/toolkit/components/passwordmgr/test/unit/test_logins_search.js
new file mode 100644
index 0000000000..c3d10b60ac
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_logins_search.js
@@ -0,0 +1,227 @@
+/**
+ * Tests methods that find specific logins in the store (searchLogins and countLogins).
+ *
+ * The getAllLogins method is not tested explicitly here, because it is used by
+ * all tests to verify additions, removals and modifications to the login store.
+ */
+
+"use strict";
+
+// Globals
+
+/**
+ * Returns a list of new nsILoginInfo objects that are a subset of the test
+ * data, built to match the specified query.
+ *
+ * @param aQuery
+ *        Each property and value of this object restricts the search to those
+ *        entries from the test data that match the property exactly.
+ */
+function buildExpectedLogins(aQuery) {
+  return TestData.loginList().filter(entry =>
+    Object.keys(aQuery).every(name => entry[name] === aQuery[name])
+  );
+}
+
+/**
+ * Tests the searchLogins function.
+ *
+ * @param aQuery
+ *        Each property and value of this object is translated to an entry in
+ *        the nsIPropertyBag parameter of searchLogins.
+ * @param aExpectedCount
+ *        Number of logins from the test data that should be found.  The actual
+ *        list of logins is obtained using the buildExpectedLogins helper, and
+ *        this value is just used to verify that modifications to the test data
+ *        don't make the current test meaningless.
+ */
+function checkSearchLogins(aQuery, aExpectedCount) {
+  info("Testing searchLogins for " + JSON.stringify(aQuery));
+
+  let expectedLogins = buildExpectedLogins(aQuery);
+  Assert.equal(expectedLogins.length, aExpectedCount);
+
+  let logins = Services.logins.searchLogins(newPropertyBag(aQuery));
+  LoginTestUtils.assertLoginListsEqual(logins, expectedLogins);
+}
+
+/**
+ * Tests searchLogins, and countLogins with the same query.
+ *
+ * @param aQuery
+ *        The "origin", "formActionOrigin", and "httpRealm" properties of this
+ *        object are passed as parameters to countLogins.  The
+ *        same object is then passed to the checkSearchLogins function.
+ * @param aExpectedCount
+ *        Number of logins from the test data that should be found.  The actual
+ *        list of logins is obtained using the buildExpectedLogins helper, and
+ *        this value is just used to verify that modifications to the test data
+ *        don't make the current test meaningless.
+ */
+function checkAllSearches(aQuery, aExpectedCount) {
+  info("Testing all search functions for " + JSON.stringify(aQuery));
+
+  let expectedLogins = buildExpectedLogins(aQuery);
+  Assert.equal(expectedLogins.length, aExpectedCount);
+
+  // The countLogins function support wildcard matches by
+  // specifying empty strings as parameters, while searchLogins requires
+  // omitting the property entirely.
+  let origin = "origin" in aQuery ? aQuery.origin : "";
+  let formActionOrigin =
+    "formActionOrigin" in aQuery ? aQuery.formActionOrigin : "";
+  let httpRealm = "httpRealm" in aQuery ? aQuery.httpRealm : "";
+
+  // Test countLogins.
+  let count = Services.logins.countLogins(origin, formActionOrigin, httpRealm);
+  Assert.equal(count, expectedLogins.length);
+
+  // Test searchLogins.
+  checkSearchLogins(aQuery, aExpectedCount);
+}
+
+// Tests
+
+/**
+ * Prepare data for the following tests.
+ */
+add_setup(async () => {
+  await Services.logins.addLogins(TestData.loginList());
+});
+
+/**
+ * Tests searchLogins, and countLogins with basic queries.
+ */
+add_task(function test_search_all_basic() {
+  // Find all logins, using no filters in the search functions.
+  checkAllSearches({}, 28);
+
+  // Find all form logins, then all authentication logins.
+  checkAllSearches({ httpRealm: null }, 17);
+  checkAllSearches({ formActionOrigin: null }, 11);
+
+  // Find all form logins on one host, then all authentication logins.
+  checkAllSearches({ origin: "http://www4.example.com", httpRealm: null }, 3);
+  checkAllSearches(
+    { origin: "http://www2.example.org", formActionOrigin: null },
+    2
+  );
+
+  // Verify that scheme and subdomain are distinct in the origin.
+  checkAllSearches({ origin: "http://www.example.com" }, 1);
+  checkAllSearches({ origin: "https://www.example.com" }, 1);
+  checkAllSearches({ origin: "https://example.com" }, 1);
+  checkAllSearches({ origin: "http://www3.example.com" }, 3);
+
+  // Verify that scheme and subdomain are distinct in formActionOrigin.
+  checkAllSearches({ formActionOrigin: "http://www.example.com" }, 2);
+  checkAllSearches({ formActionOrigin: "https://www.example.com" }, 2);
+  checkAllSearches({ formActionOrigin: "http://example.com" }, 1);
+
+  // Find by formActionOrigin on a single host.
+  checkAllSearches(
+    {
+      origin: "http://www3.example.com",
+      formActionOrigin: "http://www.example.com",
+    },
+    1
+  );
+  checkAllSearches(
+    {
+      origin: "http://www3.example.com",
+      formActionOrigin: "https://www.example.com",
+    },
+    1
+  );
+  checkAllSearches(
+    {
+      origin: "http://www3.example.com",
+      formActionOrigin: "http://example.com",
+    },
+    1
+  );
+
+  // Find by httpRealm on all hosts.
+  checkAllSearches({ httpRealm: "The HTTP Realm" }, 3);
+  checkAllSearches({ httpRealm: "ftp://ftp.example.org" }, 1);
+  checkAllSearches({ httpRealm: "The HTTP Realm Other" }, 2);
+
+  // Find by httpRealm on a single host.
+  checkAllSearches(
+    { origin: "http://example.net", httpRealm: "The HTTP Realm" },
+    1
+  );
+  checkAllSearches(
+    { origin: "http://example.net", httpRealm: "The HTTP Realm Other" },
+    1
+  );
+  checkAllSearches(
+    { origin: "ftp://example.net", httpRealm: "ftp://example.net" },
+    1
+  );
+});
+
+/**
+ * Tests searchLogins with advanced queries.
+ */
+add_task(function test_searchLogins() {
+  checkSearchLogins({ usernameField: "form_field_username" }, 12);
+  checkSearchLogins({ passwordField: "form_field_password" }, 13);
+
+  // Find all logins with an empty usernameField, including for authentication.
+  checkSearchLogins({ usernameField: "" }, 16);
+
+  // Find form logins with an empty usernameField.
+  checkSearchLogins({ httpRealm: null, usernameField: "" }, 5);
+
+  // Find logins with an empty usernameField on one host.
+  checkSearchLogins(
+    { origin: "http://www6.example.com", usernameField: "" },
+    1
+  );
+});
+
+/**
+ * Tests searchLogins with invalid arguments.
+ */
+add_task(function test_searchLogins_invalid() {
+  Assert.throws(
+    () => Services.logins.searchLogins(newPropertyBag({ username: "value" })),
+    /Unexpected field/
+  );
+});
+
+/**
+ * Tests that matches are case-sensitive, compare the full field value, and are
+ * strict when interpreting the prePath of URIs.
+ */
+add_task(function test_search_all_full_case_sensitive() {
+  checkAllSearches({ origin: "http://www.example.com" }, 1);
+  checkAllSearches({ origin: "http://www.example.com/" }, 0);
+  checkAllSearches({ origin: "example.com" }, 0);
+
+  checkAllSearches({ formActionOrigin: "http://www.example.com" }, 2);
+  checkAllSearches({ formActionOrigin: "http://www.example.com/" }, 0);
+  checkAllSearches({ formActionOrigin: "http://" }, 0);
+  checkAllSearches({ formActionOrigin: "example.com" }, 0);
+
+  checkAllSearches({ httpRealm: "The HTTP Realm" }, 3);
+  checkAllSearches({ httpRealm: "The http Realm" }, 0);
+  checkAllSearches({ httpRealm: "The HTTP" }, 0);
+  checkAllSearches({ httpRealm: "Realm" }, 0);
+});
+
+/**
+ * Tests searchLogins, and countLogins with queries that should
+ * return no values.
+ */
+add_task(function test_search_all_empty() {
+  checkAllSearches({ origin: "http://nonexistent.example.com" }, 0);
+  checkAllSearches(
+    { formActionOrigin: "http://www.example.com", httpRealm: "The HTTP Realm" },
+    0
+  );
+
+  checkSearchLogins({ origin: "" }, 0);
+  checkSearchLogins({ id: "1000" }, 0);
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_maybeImportLogin.js b/toolkit/components/passwordmgr/test/unit/test_maybeImportLogin.js
new file mode 100644
index 0000000000..fbf494d52b
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_maybeImportLogin.js
@@ -0,0 +1,368 @@
+"use strict";
+
+const HOST1 = "https://www.example.com";
+const HOST2 = "https://www.mozilla.org";
+
+const USER1 = "myuser";
+const USER2 = "anotheruser";
+
+const PASS1 = "mypass";
+const PASS2 = "anotherpass";
+const PASS3 = "yetanotherpass";
+
+async function maybeImportLogins(logins) {
+  let summary = await LoginHelper.maybeImportLogins(logins);
+  return summary.filter(ir => ir.result == "added").map(ir => ir.login);
+}
+
+add_task(async function test_invalid_logins() {
+  let importedLogins = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: "example.com", // Not an origin
+      formActionOrigin: HOST1,
+    },
+    {
+      username: USER1,
+      // no password
+      origin: HOST1,
+      formActionOrigin: HOST1,
+    },
+    {
+      username: USER2,
+      password: "", // Empty password
+      origin: HOST1,
+      formActionOrigin: HOST1,
+    },
+  ]);
+  Assert.equal(
+    importedLogins.length,
+    0,
+    `Return value should indicate no imported login: ${JSON.stringify(
+      importedLogins,
+      null,
+      2
+    )}`
+  );
+  let savedLogins = await Services.logins.getAllLogins();
+  Assert.equal(
+    savedLogins.length,
+    0,
+    `Should have no logins in storage: ${JSON.stringify(savedLogins, null, 2)}`
+  );
+  Services.logins.removeAllUserFacingLogins();
+});
+
+add_task(async function test_new_logins() {
+  let [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: HOST1 + "/",
+      formActionOrigin: HOST1 + "/",
+    },
+  ]);
+  Assert.ok(importedLogin, "Return value should indicate imported login.");
+  let matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should be 1 login for ${HOST1}`
+  );
+
+  [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: HOST2,
+      formActionOrigin: HOST2,
+    },
+  ]);
+
+  Assert.ok(
+    importedLogin,
+    "Return value should indicate another imported login."
+  );
+  matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should still be 1 login for ${HOST1}`
+  );
+
+  matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST2 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should also be 1 login for ${HOST2}`
+  );
+  Assert.equal(
+    (await Services.logins.getAllLogins()).length,
+    2,
+    "There should be 2 logins in total"
+  );
+  Services.logins.removeAllUserFacingLogins();
+});
+
+add_task(async function test_duplicate_logins() {
+  let [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: HOST1,
+      formActionOrigin: HOST1,
+    },
+  ]);
+  Assert.ok(importedLogin, "Return value should indicate imported login.");
+  let matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should be 1 login for ${HOST1}`
+  );
+
+  [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: HOST1,
+      formActionOrigin: HOST1,
+    },
+  ]);
+  Assert.ok(
+    !importedLogin,
+    "Return value should indicate no new login was imported."
+  );
+  matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should still be 1 login for ${HOST1}`
+  );
+  Services.logins.removeAllUserFacingLogins();
+});
+
+add_task(async function test_different_passwords() {
+  let [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: HOST1,
+      formActionOrigin: HOST1,
+      timeCreated: new Date(Date.now() - 1000),
+    },
+  ]);
+  Assert.ok(importedLogin, "Return value should indicate imported login.");
+  let matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should be 1 login for ${HOST1}`
+  );
+
+  // This item will be newer, so its password should take precedence.
+  [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS2,
+      origin: HOST1,
+      formActionOrigin: HOST1,
+      timeCreated: new Date(),
+    },
+  ]);
+  Assert.ok(
+    !importedLogin,
+    "Return value should not indicate imported login (as we updated an existing one)."
+  );
+  matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should still be 1 login for ${HOST1}`
+  );
+  Assert.equal(
+    matchingLogins[0].password,
+    PASS2,
+    "We should have updated the password for this login."
+  );
+
+  // Now try to update with an older password:
+  [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS3,
+      origin: HOST1,
+      formActionOrigin: HOST1,
+      timeCreated: new Date(Date.now() - 1000000),
+    },
+  ]);
+  Assert.ok(
+    !importedLogin,
+    "Return value should not indicate imported login (as we didn't update anything)."
+  );
+  matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should still be 1 login for ${HOST1}`
+  );
+  Assert.equal(
+    matchingLogins[0].password,
+    PASS2,
+    "We should NOT have updated the password for this login."
+  );
+
+  Services.logins.removeAllUserFacingLogins();
+});
+
+add_task(async function test_different_usernames_without_guid() {
+  let [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: HOST1,
+      formActionOrigin: HOST1,
+    },
+  ]);
+  Assert.ok(importedLogin, "Return value should indicate imported login.");
+  let matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should be 1 login for ${HOST1}`
+  );
+
+  [importedLogin] = await maybeImportLogins([
+    {
+      username: USER2,
+      password: PASS1,
+      origin: HOST1,
+      formActionOrigin: HOST1,
+    },
+  ]);
+  Assert.ok(
+    importedLogin,
+    "Return value should indicate another imported login."
+  );
+  matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    2,
+    `There should now be 2 logins for ${HOST1}`
+  );
+
+  Services.logins.removeAllUserFacingLogins();
+});
+
+add_task(async function test_different_usernames_with_guid() {
+  let [{ login: importedLogin }] = await LoginHelper.maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: HOST1,
+      formActionOrigin: HOST1,
+    },
+  ]);
+  Assert.ok(importedLogin, "Return value should indicate imported login.");
+  let matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should be 1 login for ${HOST1}`
+  );
+
+  info("Changing both the origin and username using the GUID");
+  let importedLogins = await LoginHelper.maybeImportLogins([
+    {
+      username: USER2,
+      password: PASS1,
+      origin: HOST2,
+      formActionOrigin: HOST1,
+      guid: importedLogin.guid,
+    },
+  ]);
+  Assert.equal(
+    importedLogins[0].result,
+    "modified",
+    "Return value should indicate an update"
+  );
+  matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST2 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `The 1 login for ${HOST1} should have been updated`
+  );
+  let storageLogin = matchingLogins[0];
+  Assert.equal(storageLogin.guid, importedLogin.guid, "Check same guid");
+  Assert.equal(storageLogin.username, USER2, "Check username updated");
+  Assert.equal(storageLogin.origin, HOST2, "Check origin updated");
+
+  Services.logins.removeAllUserFacingLogins();
+});
+
+add_task(async function test_different_targets() {
+  let [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: HOST1,
+      formActionOrigin: HOST1,
+    },
+  ]);
+  Assert.ok(importedLogin, "Return value should indicate imported login.");
+  let matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should be 1 login for ${HOST1}`
+  );
+
+  // Not passing either a formActionOrigin or a httpRealm should be treated as
+  // the same as the previous login
+  [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: HOST1,
+    },
+  ]);
+  Assert.ok(
+    !importedLogin,
+    "Return value should NOT indicate imported login " +
+      "(because a missing formActionOrigin and httpRealm should be duped to the existing login)."
+  );
+  matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    1,
+    `There should still be 1 login for ${HOST1}`
+  );
+  Assert.equal(
+    matchingLogins[0].formActionOrigin,
+    HOST1,
+    "The form submission URL should have been kept."
+  );
+
+  [importedLogin] = await maybeImportLogins([
+    {
+      username: USER1,
+      password: PASS1,
+      origin: HOST1,
+      httpRealm: HOST1,
+    },
+  ]);
+  Assert.ok(
+    importedLogin,
+    "Return value should indicate another imported login " +
+      "as an httpRealm login shouldn't be duped."
+  );
+  matchingLogins = LoginHelper.searchLoginsWithObject({ origin: HOST1 });
+  Assert.equal(
+    matchingLogins.length,
+    2,
+    `There should now be 2 logins for ${HOST1}`
+  );
+
+  Services.logins.removeAllUserFacingLogins();
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_module_LoginCSVImport.js b/toolkit/components/passwordmgr/test/unit/test_module_LoginCSVImport.js
new file mode 100644
index 0000000000..e3fa2b0ea3
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_module_LoginCSVImport.js
@@ -0,0 +1,866 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Tests the LoginCSVImport module.
+ */
+
+"use strict";
+
+const { LoginCSVImport } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginCSVImport.sys.mjs"
+);
+const { LoginExport } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginExport.sys.mjs"
+);
+const { TelemetryTestUtils: TTU } = ChromeUtils.importESModule(
+  "resource://testing-common/TelemetryTestUtils.sys.mjs"
+);
+
+// Enable the collection (during test) for all products so even products
+// that don't collect the data will be able to run the test without failure.
+Services.prefs.setBoolPref(
+  "toolkit.telemetry.testing.overrideProductsCheck",
+  true
+);
+
+const CATEGORICAL_HISTOGRAM = "PWMGR_IMPORT_LOGINS_FROM_FILE_CATEGORICAL";
+/**
+ * Given an array of strings it creates a temporary CSV file that has them as content.
+ *
+ * @param {string[]} csvLines
+ *        The lines that make up the CSV file.
+ * @param {string} extension
+ *        Optional parameter. Either 'csv' or 'tsv'. Default is 'csv'.
+ * @returns {string} The path to the CSV file that was created.
+ */
+async function setupCsv(csvLines, extension) {
+  // Cleanup state.
+  TTU.getAndClearHistogram(CATEGORICAL_HISTOGRAM);
+  Services.logins.removeAllUserFacingLogins();
+  let tmpFile = await LoginTestUtils.file.setupCsvFileWithLines(
+    csvLines,
+    extension
+  );
+  return tmpFile.path;
+}
+
+function checkMetaInfo(
+  actual,
+  expected,
+  props = ["timesUsed", "timeCreated", "timePasswordChanged", "timeLastUsed"]
+) {
+  for (let prop of props) {
+    // This will throw if not equal.
+    equal(actual[prop], expected[prop], `Check ${prop}`);
+  }
+  return true;
+}
+
+function checkLoginNewlyCreated(login) {
+  // These will throw if not equal.
+  LoginTestUtils.assertTimeIsAboutNow(login.timeCreated);
+  LoginTestUtils.assertTimeIsAboutNow(login.timePasswordChanged);
+  LoginTestUtils.assertTimeIsAboutNow(login.timeLastUsed);
+  return true;
+}
+
+/**
+ * Asserts histogram telemetry for the categories of logins
+ *
+ * @param {Object} histogram Histogram object returned from `TelemetryTestUtils.getAndClearHistogram()`
+ * @param {Number} index Index representing one of the following values in order: ["added", "modified", "error", "no_change"]. See `toolkit/components/telemetry/Histogram.json` for more information
+ * @param {Number} expected The expected number of entries in the histogram at the passed index
+ */
+function assertHistogramTelemetry(histogram, index, expected) {
+  TTU.assertHistogram(histogram, index, expected);
+}
+
+/**
+ * Ensure that an import works with TSV.
+ */
+add_task(async function test_import_tsv() {
+  let histogram = TTU.getAndClearHistogram(CATEGORICAL_HISTOGRAM);
+  let tsvFilePath = await setupCsv(
+    [
+      "url\tusername\tpassword\thttpRealm\tformActionOrigin\tguid\ttimeCreated\ttimeLastUsed\ttimePasswordChanged",
+      `https://example.com:8080\tjoe@example.com\tqwerty\tMy realm\t""\t{5ec0d12f-e194-4279-ae1b-d7d281bb46f0}\t1589617814635\t1589710449871\t1589617846802`,
+    ],
+    "tsv"
+  );
+
+  await LoginCSVImport.importFromCSV(tsvFilePath);
+  assertHistogramTelemetry(histogram, 0, 1);
+
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.authLogin({
+        formActionOrigin: null,
+        guid: "{5ec0d12f-e194-4279-ae1b-d7d281bb46f0}",
+        httpRealm: "My realm",
+        origin: "https://example.com:8080",
+        password: "qwerty",
+        passwordField: "",
+        timeCreated: 1589617814635,
+        timeLastUsed: 1589710449871,
+        timePasswordChanged: 1589617846802,
+        timesUsed: 1,
+        username: "joe@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that a new login was added with the correct fields",
+    (a, e) => a.equals(e) && checkMetaInfo(a, e)
+  );
+});
+
+/**
+ * Ensure that an import fails if there is no username column in a TSV file.
+ */
+add_task(async function test_import_tsv_with_missing_columns() {
+  let csvFilePath = await setupCsv(
+    [
+      "url\tusernameTypo\tpassword\thttpRealm\tformActionOrigin\tguid\ttimeCreated\ttimeLastUsed\ttimePasswordChanged",
+      "https://example.com\tkramer@example.com\tqwerty\tMy realm\t\t{5ec0d12f-e194-4279-ae1b-d7d281bb46f7}\t1589617814635\t1589710449871\t1589617846802",
+    ],
+    "tsv"
+  );
+
+  await Assert.rejects(
+    LoginCSVImport.importFromCSV(csvFilePath),
+    /FILE_FORMAT_ERROR/,
+    "Ensure missing username throws"
+  );
+
+  await LoginTestUtils.checkLogins(
+    [],
+    "Check that no login was added without finding columns"
+  );
+});
+
+/**
+ * Ensure that an import fails if there is no username column. We don't want
+ * to accidentally import duplicates due to a name mismatch for the username column.
+ */
+add_task(async function test_import_lacking_username_column() {
+  let csvFilePath = await setupCsv([
+    "url,usernameTypo,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    `https://example.com,joe@example.com,qwerty,My realm,,{5ec0d12f-e194-4279-ae1b-d7d281bb46f0},1589617814635,1589710449871,1589617846802`,
+  ]);
+
+  await Assert.rejects(
+    LoginCSVImport.importFromCSV(csvFilePath),
+    /FILE_FORMAT_ERROR/,
+    "Ensure missing username throws"
+  );
+
+  await LoginTestUtils.checkLogins(
+    [],
+    "Check that no login was added without finding a username column"
+  );
+});
+
+/**
+ * Ensure that an import fails if there are two columns that map to one login field.
+ */
+add_task(async function test_import_with_duplicate_fields() {
+  // Two origin columns (url & login_uri).
+  // One row has different values and the other has the same.
+  let csvFilePath = await setupCsv([
+    "url,login_uri,username,login_password",
+    "https://example.com/path,https://example.com,john@example.com,azerty",
+    "https://mozilla.org,https://mozilla.org,jdoe@example.com,qwerty",
+  ]);
+
+  await Assert.rejects(
+    LoginCSVImport.importFromCSV(csvFilePath),
+    /CONFLICTING_VALUES_ERROR/,
+    "Check that the errorType is file format error"
+  );
+
+  await LoginTestUtils.checkLogins(
+    [],
+    "Check that no login was added from a file with duplicated columns"
+  );
+});
+
+/**
+ * Ensure that an import fails if there are two identical columns.
+ */
+add_task(async function test_import_with_duplicate_columns() {
+  let csvFilePath = await setupCsv([
+    "url,username,password,password",
+    "https://example.com/path,john@example.com,azerty,12345",
+  ]);
+
+  await Assert.rejects(
+    LoginCSVImport.importFromCSV(csvFilePath),
+    /CONFLICTING_VALUES_ERROR/,
+    "Check that the errorType is file format error"
+  );
+
+  await LoginTestUtils.checkLogins(
+    [],
+    "Check that no login was added from a file with duplicated columns"
+  );
+});
+
+/**
+ * Ensure that import is allowed with only origin, username, password and that
+ * one can mix and match column naming between conventions from different
+ * password managers (so that we better support new/unknown password managers).
+ */
+add_task(async function test_import_minimal_with_mixed_naming() {
+  let csvFilePath = await setupCsv([
+    "url,username,login_password",
+    "ftp://example.com,john@example.com,azerty",
+  ]);
+
+  await LoginCSVImport.importFromCSV(csvFilePath);
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.formLogin({
+        formActionOrigin: "",
+        httpRealm: null,
+        origin: "ftp://example.com",
+        password: "azerty",
+        passwordField: "",
+        timesUsed: 1,
+        username: "john@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that a new login was added with the correct fields",
+    (a, e) =>
+      a.equals(e) &&
+      checkMetaInfo(a, e, ["timesUsed"]) &&
+      checkLoginNewlyCreated(a)
+  );
+});
+
+/**
+ * Imports login data from the latest Firefox CSV file for various logins from
+ * LoginTestUtils.testData.loginList().
+ */
+add_task(async function test_import_from_firefox_various_latest() {
+  await setupCsv([]);
+  info("Populate the login list for export");
+  let logins = LoginTestUtils.testData.loginList();
+  await Services.logins.addLogins(logins);
+
+  let tmpFilePath = FileTestUtils.getTempFile("logins.csv").path;
+  await LoginExport.exportAsCSV(tmpFilePath);
+
+  await LoginCSVImport.importFromCSV(tmpFilePath);
+
+  await LoginTestUtils.checkLogins(
+    logins,
+    "Check that all of LoginTestUtils.testData.loginList can be re-imported"
+  );
+});
+
+/**
+ * Imports login data from a Firefox CSV file without quotes.
+ */
+add_task(async function test_import_from_firefox_auth() {
+  let csvFilePath = await setupCsv([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    `https://example.com:8080,joe@example.com,qwerty,My realm,"",{5ec0d12f-e194-4279-ae1b-d7d281bb46f0},1589617814635,1589710449871,1589617846802`,
+  ]);
+
+  await LoginCSVImport.importFromCSV(csvFilePath);
+
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.authLogin({
+        formActionOrigin: null,
+        guid: "{5ec0d12f-e194-4279-ae1b-d7d281bb46f0}",
+        httpRealm: "My realm",
+        origin: "https://example.com:8080",
+        password: "qwerty",
+        passwordField: "",
+        timeCreated: 1589617814635,
+        timeLastUsed: 1589710449871,
+        timePasswordChanged: 1589617846802,
+        timesUsed: 1,
+        username: "joe@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that a new login was added with the correct fields",
+    (a, e) => a.equals(e) && checkMetaInfo(a, e)
+  );
+});
+
+/**
+ * Imports login data from a Firefox CSV file with quotes.
+ */
+add_task(async function test_import_from_firefox_auth_with_quotes() {
+  let csvFilePath = await setupCsv([
+    '"url","username","password","httpRealm","formActionOrigin","guid","timeCreated","timeLastUsed","timePasswordChanged"',
+    '"https://example.com","joe@example.com","qwerty2","My realm",,"{5ec0d12f-e194-4279-ae1b-d7d281bb46f0}","1589617814635","1589710449871","1589617846802"',
+  ]);
+
+  await LoginCSVImport.importFromCSV(csvFilePath);
+
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.authLogin({
+        formActionOrigin: null,
+        httpRealm: "My realm",
+        origin: "https://example.com",
+        password: "qwerty2",
+        passwordField: "",
+        timeCreated: 1589617814635,
+        timeLastUsed: 1589710449871,
+        timePasswordChanged: 1589617846802,
+        timesUsed: 1,
+        username: "joe@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that a new login was added with the correct fields",
+    (a, e) => a.equals(e) && checkMetaInfo(a, e)
+  );
+});
+
+/**
+ * Imports login data from a Firefox CSV file where only cells containing a comma are quoted.
+ */
+add_task(async function test_import_from_firefox_auth_some_quoted_fields() {
+  let csvFilePath = await setupCsv([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    'https://example.com,joe@example.com,"one,two,tree","My realm",,{5ec0d12f-e194-4279-ae1b-d7d281bb46f0},1589617814635,1589710449871,1589617846802',
+  ]);
+
+  await LoginCSVImport.importFromCSV(csvFilePath);
+
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.authLogin({
+        formActionOrigin: null,
+        httpRealm: "My realm",
+        origin: "https://example.com",
+        password: "one,two,tree",
+        passwordField: "",
+        timeCreated: 1589617814635,
+        timePasswordChanged: 1589617846802,
+        timeLastUsed: 1589710449871,
+        timesUsed: 1,
+        username: "joe@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that a new login was added with the correct fields",
+    (a, e) => a.equals(e) && checkMetaInfo(a, e)
+  );
+});
+
+/**
+ * Imports login data from a Firefox CSV file with an empty formActionOrigin and null httpRealm
+ */
+add_task(async function test_import_from_firefox_form_empty_formActionOrigin() {
+  let csvFilePath = await setupCsv([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://example.com,joe@example.com,s3cret1,,,{5ec0d12f-e194-4279-ae1b-d7d281bb46f0},1589617814636,1589710449872,1589617846803",
+  ]);
+
+  await LoginCSVImport.importFromCSV(csvFilePath);
+
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.formLogin({
+        formActionOrigin: "",
+        httpRealm: null,
+        origin: "https://example.com",
+        password: "s3cret1",
+        passwordField: "",
+        timeCreated: 1589617814636,
+        timePasswordChanged: 1589617846803,
+        timeLastUsed: 1589710449872,
+        timesUsed: 1,
+        username: "joe@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that a new login was added with the correct fields",
+    (a, e) => a.equals(e) && checkMetaInfo(a, e)
+  );
+});
+
+/**
+ * Imports login data from a Firefox CSV file with a non-empty formActionOrigin and null httpRealm.
+ */
+add_task(async function test_import_from_firefox_form_with_formActionOrigin() {
+  let csvFilePath = await setupCsv([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "http://example.com,joe@example.com,s3cret1,,https://other.example.com,{5ec0d12f-e194-4279-ae1b-d7d281bb46f1},1589617814635,1589710449871,1589617846802",
+  ]);
+
+  await LoginCSVImport.importFromCSV(csvFilePath);
+
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.formLogin({
+        formActionOrigin: "https://other.example.com",
+        httpRealm: null,
+        origin: "http://example.com",
+        password: "s3cret1",
+        passwordField: "",
+        timeCreated: 1589617814635,
+        timePasswordChanged: 1589617846802,
+        timeLastUsed: 1589710449871,
+        timesUsed: 1,
+        username: "joe@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that a new login was added with the correct fields",
+    (a, e) => a.equals(e) && checkMetaInfo(a, e)
+  );
+});
+
+/**
+ * Imports login data from a Bitwarden CSV file.
+ * `name` is ignored until bug 1433770.
+ */
+add_task(async function test_import_from_bitwarden_csv() {
+  let csvFilePath = await setupCsv([
+    "folder,favorite,type,name,notes,fields,login_uri,login_username,login_password,login_totp",
+    `,,note,jane's note,"secret note, ignore me!",,,,,`,
+    ",,login,example.com,,,https://example.com/login,jane@example.com,secret_password",
+  ]);
+
+  await LoginCSVImport.importFromCSV(csvFilePath);
+
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.formLogin({
+        formActionOrigin: "",
+        httpRealm: null,
+        origin: "https://example.com",
+        password: "secret_password",
+        passwordField: "",
+        timesUsed: 1,
+        username: "jane@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that a new Bitwarden login was added with the correct fields",
+    (a, e) =>
+      a.equals(e) &&
+      checkMetaInfo(a, e, ["timesUsed"]) &&
+      checkLoginNewlyCreated(a)
+  );
+});
+
+/**
+ * Imports login data from a Chrome CSV file.
+ * `name` is ignored until bug 1433770.
+ */
+add_task(async function test_import_from_chrome_csv() {
+  let csvFilePath = await setupCsv([
+    "name,url,username,password",
+    "example.com,https://example.com/login,jane@example.com,secret_chrome_password",
+  ]);
+
+  await LoginCSVImport.importFromCSV(csvFilePath);
+
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.formLogin({
+        formActionOrigin: "",
+        httpRealm: null,
+        origin: "https://example.com",
+        password: "secret_chrome_password",
+        passwordField: "",
+        timesUsed: 1,
+        username: "jane@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that a new Chrome login was added with the correct fields",
+    (a, e) =>
+      a.equals(e) &&
+      checkMetaInfo(a, e, ["timesUsed"]) &&
+      checkLoginNewlyCreated(a)
+  );
+});
+
+/**
+ * Imports login data with an item without the username.
+ */
+add_task(async function test_import_login_without_username() {
+  let csvFilePath = await setupCsv([
+    "url,username,password",
+    "https://example.com/login,,secret_password",
+  ]);
+
+  await LoginCSVImport.importFromCSV(csvFilePath);
+
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.formLogin({
+        formActionOrigin: "",
+        httpRealm: null,
+        origin: "https://example.com",
+        password: "secret_password",
+        passwordField: "",
+        timesUsed: 1,
+        username: "",
+        usernameField: "",
+      }),
+    ],
+    "Check that a Login is added without an username",
+    (a, e) =>
+      a.equals(e) &&
+      checkMetaInfo(a, e, ["timesUsed"]) &&
+      checkLoginNewlyCreated(a)
+  );
+});
+
+/**
+ * Imports login data from a KeepassXC CSV file.
+ * `Title` is ignored until bug 1433770.
+ */
+add_task(async function test_import_from_keepassxc_csv() {
+  let csvFilePath = await setupCsv([
+    `"Group","Title","Username","Password","URL","Notes"`,
+    `"NewDatabase/Internet","Amazing","test@example.com","<password>","https://example.org",""`,
+  ]);
+
+  await LoginCSVImport.importFromCSV(csvFilePath);
+
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.formLogin({
+        formActionOrigin: "",
+        httpRealm: null,
+        origin: "https://example.org",
+        password: "<password>",
+        passwordField: "",
+        timesUsed: 1,
+        username: "test@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that a new KeepassXC login was added with the correct fields",
+    (a, e) =>
+      a.equals(e) &&
+      checkMetaInfo(a, e, ["timesUsed"]) &&
+      checkLoginNewlyCreated(a)
+  );
+});
+
+/**
+ * Imports login data summary contains added logins.
+ */
+add_task(async function test_import_summary_contains_added_login() {
+  let csvFilePath = await setupCsv([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://added.example.com,jane@example.com,added_passwordd,My realm,,{5ec0d12f-e194-4279-ae1b-d7d281bb0003},1589617814635,1589710449871,1589617846802",
+  ]);
+
+  let [added] = await LoginCSVImport.importFromCSV(csvFilePath);
+
+  equal(added.result, "added", `Check that the login was added`);
+});
+
+/**
+ * Imports login data summary contains modified logins without guid.
+ */
+add_task(async function test_import_summary_modified_login_without_guid() {
+  let histogram = TTU.getAndClearHistogram(CATEGORICAL_HISTOGRAM);
+  let initialDataFile = await setupCsv([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://modifiedwithoutguid.example.com,gini@example.com,initial_password,My realm,,,1589617814635,1589710449871,1589617846802",
+  ]);
+  await LoginCSVImport.importFromCSV(initialDataFile);
+  assertHistogramTelemetry(histogram, 0, 1);
+  histogram = TTU.getAndClearHistogram(CATEGORICAL_HISTOGRAM);
+
+  let csvFile = await LoginTestUtils.file.setupCsvFileWithLines([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://modifiedwithoutguid.example.com,gini@example.com,modified_password,My realm,,,1589617814635,1589710449871,1589617846999",
+  ]);
+
+  let [modifiedWithoutGuid] = await LoginCSVImport.importFromCSV(csvFile.path);
+  assertHistogramTelemetry(histogram, 1, 1);
+  equal(
+    modifiedWithoutGuid.result,
+    "modified",
+    `Check that the login was modified when there was no guid data`
+  );
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.authLogin({
+        formActionOrigin: null,
+        guid: null,
+        httpRealm: "My realm",
+        origin: "https://modifiedwithoutguid.example.com",
+        password: "modified_password",
+        passwordField: "",
+        timeCreated: 1589617814635,
+        timeLastUsed: 1589710449871,
+        timePasswordChanged: 1589617846999,
+        timesUsed: 1,
+        username: "gini@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that logins were updated with the correct fields",
+    (a, e) => a.equals(e) && checkMetaInfo(a, e)
+  );
+});
+
+/**
+ * Imports login data summary contains modified logins with guid.
+ */
+add_task(async function test_import_summary_modified_login_with_guid() {
+  let initialDataFile = await setupCsv([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://modifiedwithguid.example.com,jane@example.com,initial_password,My realm,,{5ec0d12f-e194-4279-ae1b-d7d281bb0001},1589617814635,1589710449871,1589617846802",
+  ]);
+  await LoginCSVImport.importFromCSV(initialDataFile);
+
+  let csvFile = await LoginTestUtils.file.setupCsvFileWithLines([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://modified.example.com,jane@example.com,modified_password,My realm,,{5ec0d12f-e194-4279-ae1b-d7d281bb0001},1589617814635,1589710449871,1589617846999",
+  ]);
+
+  let [modifiedWithGuid] = await LoginCSVImport.importFromCSV(csvFile.path);
+
+  equal(
+    modifiedWithGuid.result,
+    "modified",
+    `Check that the login was modified when it had the same guid`
+  );
+  await LoginTestUtils.checkLogins(
+    [
+      TestData.authLogin({
+        formActionOrigin: null,
+        guid: "{5ec0d12f-e194-4279-ae1b-d7d281bb0001}",
+        httpRealm: "My realm",
+        origin: "https://modified.example.com",
+        password: "modified_password",
+        passwordField: "",
+        timeCreated: 1589617814635,
+        timeLastUsed: 1589710449871,
+        timePasswordChanged: 1589617846999,
+        timesUsed: 1,
+        username: "jane@example.com",
+        usernameField: "",
+      }),
+    ],
+    "Check that logins were updated with the correct fields",
+    (a, e) => a.equals(e) && checkMetaInfo(a, e)
+  );
+});
+
+/**
+ * Imports login data summary contains unchanged logins.
+ */
+add_task(async function test_import_summary_contains_unchanged_login() {
+  let histogram = TTU.getAndClearHistogram(CATEGORICAL_HISTOGRAM);
+  let initialDataFile = await setupCsv([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://nochange.example.com,jane@example.com,nochange_password,My realm,,{5ec0d12f-e194-4279-ae1b-d7d281bb0002},1589617814635,1589710449871,1589617846802",
+  ]);
+  await LoginCSVImport.importFromCSV(initialDataFile);
+  assertHistogramTelemetry(histogram, 0, 1);
+  histogram = TTU.getAndClearHistogram(CATEGORICAL_HISTOGRAM);
+
+  let csvFile = await LoginTestUtils.file.setupCsvFileWithLines([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://nochange.example.com,jane@example.com,nochange_password,My realm,,{5ec0d12f-e194-4279-ae1b-d7d281bb0002},1589617814635,1589710449871,1589617846802",
+  ]);
+
+  let [noChange] = await LoginCSVImport.importFromCSV(csvFile.path);
+  assertHistogramTelemetry(histogram, 3, 1);
+  equal(noChange.result, "no_change", `Check that the login was not changed`);
+});
+
+/**
+ * Imports login data summary contains logins with errors in case of missing fields.
+ */
+add_task(async function test_import_summary_contains_missing_fields_errors() {
+  let histogram = TTU.getAndClearHistogram(CATEGORICAL_HISTOGRAM);
+  const missingFieldsToCheck = ["url", "password"];
+  const sourceObject = {
+    url: "https://invalid.password.example.com",
+    username: "jane@example.com",
+    password: "qwerty",
+  };
+  for (const missingField of missingFieldsToCheck) {
+    const clonedUser = { ...sourceObject };
+    clonedUser[missingField] = "";
+    let csvFilePath = await setupCsv([
+      "url,username,password",
+      `${clonedUser.url},${clonedUser.username},${clonedUser.password}`,
+    ]);
+
+    let [importLogin] = await LoginCSVImport.importFromCSV(csvFilePath);
+
+    equal(
+      importLogin.result,
+      "error_missing_field",
+      `Check that the missing field error is reported for ${missingField}`
+    );
+    equal(
+      importLogin.field_name,
+      missingField,
+      `Check that the invalid field name is correctly reported for the ${missingField}`
+    );
+  }
+  assertHistogramTelemetry(histogram, 2, 1);
+});
+
+/**
+ * Imports login with wrong file format will have correct errorType.
+ */
+add_task(async function test_import_summary_with_bad_format() {
+  let csvFilePath = await setupCsv(["password", "123qwe!@#QWE"]);
+
+  await Assert.rejects(
+    LoginCSVImport.importFromCSV(csvFilePath),
+    /FILE_FORMAT_ERROR/,
+    "Check that the errorType is file format error"
+  );
+
+  await LoginTestUtils.checkLogins(
+    [],
+    "Check that no login was added with bad format"
+  );
+});
+
+/**
+ * Imports login with wrong file type will have correct errorType.
+ */
+add_task(async function test_import_summary_with_non_csv_file() {
+  let csvFilePath = await setupCsv([
+    "<body>this is totally not a csv file</body>",
+  ]);
+
+  await Assert.rejects(
+    LoginCSVImport.importFromCSV(csvFilePath),
+    /FILE_FORMAT_ERROR/,
+    "Check that the errorType is file format error"
+  );
+
+  await LoginTestUtils.checkLogins(
+    [],
+    "Check that no login was added with file of different format"
+  );
+});
+
+/**
+ * Imports login multiple url and user will import the first and skip the second.
+ */
+add_task(async function test_import_summary_with_url_user_multiple_values() {
+  let csvFilePath = await setupCsv([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://example.com,jane@example.com,password1,My realm",
+    "https://example.com,jane@example.com,password2,My realm",
+  ]);
+
+  let initialLoginCount = (await Services.logins.getAllLogins()).length;
+
+  let results = await LoginCSVImport.importFromCSV(csvFilePath);
+  let afterImportLoginCount = (await Services.logins.getAllLogins()).length;
+
+  equal(results.length, 2, `Check that we got a result for each imported row`);
+  equal(results[0].result, "added", `Check that the first login was added`);
+  equal(
+    results[1].result,
+    "no_change",
+    `Check that the second login was skipped`
+  );
+  equal(initialLoginCount, 0, `Check that initially we had no logins`);
+  equal(afterImportLoginCount, 1, `Check that we imported only one login`);
+});
+
+/**
+ * Imports login with duplicated guid values throws error.
+ */
+add_task(async function test_import_summary_with_duplicated_guid_values() {
+  let csvFilePath = await setupCsv([
+    "url,username,password,httpRealm,formActionOrigin,guid,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://example1.com,jane1@example.com,password1,My realm,,{5ec0d12f-e194-4279-ae1b-d7d281bb0004},1589617814635,1589710449871,1589617846802",
+    "https://example2.com,jane2@example.com,password2,My realm,,{5ec0d12f-e194-4279-ae1b-d7d281bb0004},1589617814635,1589710449871,1589617846802",
+  ]);
+  let initialLoginCount = (await Services.logins.getAllLogins()).length;
+
+  let results = await LoginCSVImport.importFromCSV(csvFilePath);
+  let afterImportLoginCount = (await Services.logins.getAllLogins()).length;
+
+  equal(results.length, 2, `Check that we got a result for each imported row`);
+  equal(results[0].result, "added", `Check that the first login was added`);
+  equal(results[1].result, "error", `Check that the second login was an error`);
+  equal(initialLoginCount, 0, `Check that initially we had no logins`);
+  equal(afterImportLoginCount, 1, `Check that we imported only one login`);
+});
+
+/**
+ * Imports login with different passwords will pick up the newest one and ignore the oldest one.
+ */
+add_task(async function test_import_summary_with_different_time_changed() {
+  let csvFilePath = await setupCsv([
+    "url,username,password,timeCreated,timeLastUsed,timePasswordChanged",
+    "https://example.com,eve@example.com,old password,1589617814635,1589710449800,1589617846800",
+    "https://example.com,eve@example.com,new password,1589617814635,1589710449801,1589617846801",
+  ]);
+  let initialLoginCount = (await Services.logins.getAllLogins()).length;
+
+  let results = await LoginCSVImport.importFromCSV(csvFilePath);
+  let afterImportLoginCount = (await Services.logins.getAllLogins()).length;
+
+  equal(results.length, 2, `Check that we got a result for each imported row`);
+  equal(
+    results[0].result,
+    "no_change",
+    `Check that the oldest password is skipped`
+  );
+  equal(
+    results[1].login.password,
+    "new password",
+    `Check that the newest password is imported`
+  );
+  equal(
+    results[1].result,
+    "added",
+    `Check that the newest password result is correct`
+  );
+  equal(initialLoginCount, 0, `Check that initially we had no logins`);
+  equal(afterImportLoginCount, 1, `Check that we imported only one login`);
+});
+
+/**
+ * Imports duplicate logins as one without an error.
+ */
+add_task(async function test_import_duplicate_logins_as_one() {
+  let csvFilePath = await setupCsv([
+    "name,url,username,password",
+    "somesite,https://example.com/,user@example.com,asdasd123123",
+    "somesite,https://example.com/,user@example.com,asdasd123123",
+  ]);
+  let initialLoginCount = (await Services.logins.getAllLogins()).length;
+
+  let results = await LoginCSVImport.importFromCSV(csvFilePath);
+  let afterImportLoginCount = (await Services.logins.getAllLogins()).length;
+
+  equal(results.length, 2, `Check that we got a result for each imported row`);
+  equal(
+    results[0].result,
+    "added",
+    `Check that the first login login was added`
+  );
+  equal(
+    results[1].result,
+    "no_change",
+    `Check that the second login was not changed`
+  );
+
+  equal(initialLoginCount, 0, `Check that initially we had no logins`);
+  equal(afterImportLoginCount, 1, `Check that we imported only one login`);
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_module_LoginExport.js b/toolkit/components/passwordmgr/test/unit/test_module_LoginExport.js
new file mode 100644
index 0000000000..6c83ff0005
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_module_LoginExport.js
@@ -0,0 +1,222 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Tests the LoginExport module.
+ */
+
+"use strict";
+
+let { LoginExport } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginExport.sys.mjs"
+);
+let { sinon } = ChromeUtils.importESModule(
+  "resource://testing-common/Sinon.sys.mjs"
+);
+
+/**
+ * Saves the logins to a temporary CSV file, reads the lines and returns the CSV lines.
+ * After extracting the CSV lines, it deletes the tmp file.
+ */
+async function exportAsCSVInTmpFile() {
+  const tmpFilePath = FileTestUtils.getTempFile("logins.csv").path;
+  await LoginExport.exportAsCSV(tmpFilePath);
+  const csvString = await IOUtils.readUTF8(tmpFilePath);
+  await IOUtils.remove(tmpFilePath);
+  // CSV uses CRLF
+  return csvString.split(/\r\n/);
+}
+
+const COMMON_LOGIN_MODS = {
+  guid: "{5ec0d12f-e194-4279-ae1b-d7d281bb46f0}",
+  timeCreated: 1589617814635,
+  timeLastUsed: 1589710449871,
+  timePasswordChanged: 1589617846802,
+  timesUsed: 1,
+  username: "joe@example.com",
+  password: "qwerty",
+  origin: "https://example.com",
+};
+
+/**
+ * Generates a new login object with all the form login fields populated.
+ */
+function exportFormLogin(modifications) {
+  return LoginTestUtils.testData.formLogin({
+    ...COMMON_LOGIN_MODS,
+    formActionOrigin: "https://action.example.com",
+    ...modifications,
+  });
+}
+
+function exportAuthLogin(modifications) {
+  return LoginTestUtils.testData.authLogin({
+    ...COMMON_LOGIN_MODS,
+    httpRealm: "My realm",
+    ...modifications,
+  });
+}
+
+add_setup(async () => {
+  let oldLogins = Services.logins;
+  Services.logins = { getAllLogins: sinon.stub() };
+  registerCleanupFunction(() => {
+    Services.logins = oldLogins;
+  });
+});
+
+add_task(async function test_buildCSVRow() {
+  let testObject = {
+    null: null,
+    emptyString: "",
+    number: 99,
+    string: "Foo",
+  };
+  Assert.deepEqual(
+    LoginExport._buildCSVRow(testObject, [
+      "null",
+      "emptyString",
+      "number",
+      "string",
+    ]),
+    ["", `""`, `"99"`, `"Foo"`],
+    "Check _buildCSVRow with different types"
+  );
+});
+
+add_task(async function test_no_new_properties_to_export() {
+  let login = exportFormLogin();
+  Assert.deepEqual(
+    Object.keys(login),
+    [
+      "QueryInterface",
+      "displayOrigin",
+      "origin",
+      "hostname",
+      "formActionOrigin",
+      "formSubmitURL",
+      "httpRealm",
+      "username",
+      "usernameField",
+      "password",
+      "passwordField",
+      "unknownFields",
+      "everSynced",
+      "syncCounter",
+      "init",
+      "equals",
+      "matches",
+      "clone",
+      "guid",
+      "timeCreated",
+      "timeLastUsed",
+      "timePasswordChanged",
+      "timesUsed",
+    ],
+    "Check that no new properties were added to a login that should maybe be exported"
+  );
+});
+
+add_task(async function test_export_one_form_login() {
+  let login = exportFormLogin();
+  Services.logins.getAllLogins.returns([login]);
+
+  let rows = await exportAsCSVInTmpFile();
+
+  Assert.equal(
+    rows[0],
+    '"url","username","password","httpRealm","formActionOrigin","guid","timeCreated","timeLastUsed","timePasswordChanged"',
+    "checking csv headers"
+  );
+  Assert.equal(
+    rows[1],
+    '"https://example.com","joe@example.com","qwerty",,"https://action.example.com","{5ec0d12f-e194-4279-ae1b-d7d281bb46f0}","1589617814635","1589710449871","1589617846802"',
+    `checking login is saved as CSV row\n${JSON.stringify(login)}\n`
+  );
+});
+
+add_task(async function test_export_one_auth_login() {
+  let login = exportAuthLogin();
+  Services.logins.getAllLogins.returns([login]);
+
+  let rows = await exportAsCSVInTmpFile();
+
+  Assert.equal(
+    rows[0],
+    '"url","username","password","httpRealm","formActionOrigin","guid","timeCreated","timeLastUsed","timePasswordChanged"',
+    "checking csv headers"
+  );
+  Assert.equal(
+    rows[1],
+    '"https://example.com","joe@example.com","qwerty","My realm",,"{5ec0d12f-e194-4279-ae1b-d7d281bb46f0}","1589617814635","1589710449871","1589617846802"',
+    `checking login is saved as CSV row\n${JSON.stringify(login)}\n`
+  );
+});
+
+add_task(async function test_export_escapes_values() {
+  let login = exportFormLogin({
+    password: "!@#$%^&*()_+,'",
+  });
+  Services.logins.getAllLogins.returns([login]);
+
+  let rows = await exportAsCSVInTmpFile();
+
+  Assert.equal(
+    rows[1],
+    '"https://example.com","joe@example.com","!@#$%^&*()_+,\'",,"https://action.example.com","{5ec0d12f-e194-4279-ae1b-d7d281bb46f0}","1589617814635","1589710449871","1589617846802"',
+    `checking login correctly escapes CSV characters \n${JSON.stringify(login)}`
+  );
+});
+
+add_task(async function test_export_multiple_rows() {
+  let logins = await LoginTestUtils.testData.loginList();
+  // Note, because we're stubbing this method and avoiding the actual login manager logic,
+  // login de-duplication does not occur
+  Services.logins.getAllLogins.returns(logins);
+
+  let actualRows = await exportAsCSVInTmpFile();
+  let expectedRows = [
+    '"url","username","password","httpRealm","formActionOrigin","guid","timeCreated","timeLastUsed","timePasswordChanged"',
+    '"http://www.example.com","the username","the password for www.example.com",,"http://www.example.com",,,,',
+    '"https://www.example.com","the username","the password for https",,"https://www.example.com",,,,',
+    '"https://example.com","the username","the password for example.com",,"https://example.com",,,,',
+    '"http://www3.example.com","the username","the password",,"http://www.example.com",,,,',
+    '"http://www3.example.com","the username","the password",,"https://www.example.com",,,,',
+    '"http://www3.example.com","the username","the password",,"http://example.com",,,,',
+    '"http://www4.example.com","username one","password one",,"http://www4.example.com",,,,',
+    '"http://www4.example.com","username two","password two",,"http://www4.example.com",,,,',
+    '"http://www4.example.com","","password three",,"http://www4.example.com",,,,',
+    '"http://www5.example.com","multi username","multi password",,"http://www5.example.com",,,,',
+    '"http://www6.example.com","","12345",,"http://www6.example.com",,,,',
+    '"https://www7.example.com:8080","8080_username","8080_pass",,"https://www7.example.com:8080",,,,',
+    '"https://www7.example.com:8080","8080_username2","8080_pass2","My dev server",,,,,',
+    '"http://www.example.org","the username","the password","The HTTP Realm",,,,,',
+    '"ftp://ftp.example.org","the username","the password","ftp://ftp.example.org",,,,,',
+    '"http://www2.example.org","the username","the password","The HTTP Realm",,,,,',
+    '"http://www2.example.org","the username other","the password other","The HTTP Realm Other",,,,,',
+    '"http://example.net","the username","the password",,"http://example.net",,,,',
+    '"http://example.net","the username","the password",,"http://www.example.net",,,,',
+    '"http://example.net","username two","the password",,"http://www.example.net",,,,',
+    '"http://example.net","the username","the password","The HTTP Realm",,,,,',
+    '"http://example.net","username two","the password","The HTTP Realm Other",,,,,',
+    '"ftp://example.net","the username","the password","ftp://example.net",,,,,',
+    '"http://example.net","the username","the password","",,,,,',
+    '"chrome://example_extension","the username","the password one","Example Login One",,,,,',
+    '"chrome://example_extension","the username","the password two","Example Login Two",,,,,',
+    '"file://","file: username","file: password",,"file://",,,,',
+    '"https://js.example.com","javascript: username","javascript: password",,"javascript:",,,,',
+  ];
+
+  Assert.equal(actualRows.length, expectedRows.length, "Check number of lines");
+  for (let i = 0; i < logins.length; i++) {
+    let login = logins[i];
+    Assert.equal(
+      actualRows[i],
+      expectedRows[i],
+      `checking CSV correctly writes row at index=${i} \n${JSON.stringify(
+        login
+      )}\n`
+    );
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_module_LoginManager.js b/toolkit/components/passwordmgr/test/unit/test_module_LoginManager.js
new file mode 100644
index 0000000000..8ab75bdeef
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_module_LoginManager.js
@@ -0,0 +1,37 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Tests the LoginManager module.
+ */
+
+"use strict";
+
+const { LoginManager } = ChromeUtils.importESModule(
+  "resource://gre/modules/LoginManager.sys.mjs"
+);
+
+add_task(async function test_ensureCurrentSyncID() {
+  let loginManager = new LoginManager();
+  await loginManager.setSyncID(1);
+  await loginManager.setLastSync(100);
+
+  // test calling ensureCurrentSyncID with the current sync ID
+  Assert.equal(await loginManager.ensureCurrentSyncID(1), 1);
+  Assert.equal(await loginManager.getSyncID(), 1, "sync ID shouldn't change");
+  Assert.equal(
+    await loginManager.getLastSync(),
+    100,
+    "last sync shouldn't change"
+  );
+
+  // test calling ensureCurrentSyncID with the different sync ID
+  Assert.equal(await loginManager.ensureCurrentSyncID(2), 2);
+  Assert.equal(await loginManager.getSyncID(), 2, "sync ID should be updated");
+  Assert.equal(
+    await loginManager.getLastSync(),
+    0,
+    "last sync should be reset"
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_module_LoginStore.js b/toolkit/components/passwordmgr/test/unit/test_module_LoginStore.js
new file mode 100644
index 0000000000..f7e764c789
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_module_LoginStore.js
@@ -0,0 +1,337 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests the LoginStore object.
+ */
+
+"use strict";
+
+// Globals
+
+ChromeUtils.defineESModuleGetters(this, {
+  LoginStore: "resource://gre/modules/LoginStore.sys.mjs",
+});
+
+const TEST_STORE_FILE_NAME = "test-logins.json";
+
+const MAX_DATE_MS = 8640000000000000;
+
+// Tests
+
+/**
+ * Saves login data to a file, then reloads it.
+ */
+add_task(async function test_save_reload() {
+  let storeForSave = new LoginStore(getTempFile(TEST_STORE_FILE_NAME).path);
+
+  // The "load" method must be called before preparing the data to be saved.
+  await storeForSave.load();
+
+  let rawLoginData = {
+    id: storeForSave.data.nextId++,
+    hostname: "http://www.example.com",
+    httpRealm: null,
+    formSubmitURL: "http://www.example.com",
+    usernameField: "field_" + String.fromCharCode(533, 537, 7570, 345),
+    passwordField: "field_" + String.fromCharCode(421, 259, 349, 537),
+    encryptedUsername: "(test)",
+    encryptedPassword: "(test)",
+    guid: "(test)",
+    encType: Ci.nsILoginManagerCrypto.ENCTYPE_SDR,
+    timeCreated: Date.now(),
+    timeLastUsed: Date.now(),
+    timePasswordChanged: Date.now(),
+    timesUsed: 1,
+  };
+  storeForSave.data.logins.push(rawLoginData);
+
+  await storeForSave._save();
+
+  // Test the asynchronous initialization path.
+  let storeForLoad = new LoginStore(storeForSave.path);
+  await storeForLoad.load();
+
+  Assert.equal(storeForLoad.data.logins.length, 1);
+  Assert.deepEqual(storeForLoad.data.logins[0], rawLoginData);
+
+  // Test the synchronous initialization path.
+  storeForLoad = new LoginStore(storeForSave.path);
+  storeForLoad.ensureDataReady();
+
+  Assert.equal(storeForLoad.data.logins.length, 1);
+  Assert.deepEqual(storeForLoad.data.logins[0], rawLoginData);
+});
+
+/**
+ * Checks that loading from a missing file results in empty arrays.
+ */
+add_task(async function test_load_empty() {
+  let store = new LoginStore(getTempFile(TEST_STORE_FILE_NAME).path);
+
+  Assert.equal(false, await IOUtils.exists(store.path));
+
+  await store.load();
+
+  Assert.equal(false, await IOUtils.exists(store.path));
+
+  Assert.equal(store.data.logins.length, 0);
+});
+
+/**
+ * Checks that saving empty data still overwrites any existing file.
+ */
+add_task(async function test_save_empty() {
+  const store = new LoginStore(getTempFile(TEST_STORE_FILE_NAME).path);
+
+  await store.load();
+  await IOUtils.writeUTF8(store.path, "", { writeMode: "create" });
+  await store._save();
+
+  Assert.ok(await IOUtils.exists(store.path));
+});
+
+/**
+ * Loads data from a string in a predefined format.  The purpose of this test is
+ * to verify that the JSON format used in previous versions can be loaded.
+ */
+add_task(async function test_load_string_predefined() {
+  let store = new LoginStore(getTempFile(TEST_STORE_FILE_NAME).path);
+
+  let string =
+    '{"logins":[{' +
+    '"id":1,' +
+    '"hostname":"http://www.example.com",' +
+    '"httpRealm":null,' +
+    '"formSubmitURL":"http://www.example.com",' +
+    '"usernameField":"usernameField",' +
+    '"passwordField":"passwordField",' +
+    '"encryptedUsername":"(test)",' +
+    '"encryptedPassword":"(test)",' +
+    '"guid":"(test)",' +
+    '"encType":1,' +
+    '"timeCreated":1262304000000,' +
+    '"timeLastUsed":1262390400000,' +
+    '"timePasswordChanged":1262476800000,' +
+    '"timesUsed":1}],"disabledHosts":[' +
+    '"http://www.example.org"]}';
+
+  await IOUtils.writeUTF8(store.path, string, {
+    tmpPath: store.path + ".tmp",
+  });
+
+  await store.load();
+
+  Assert.equal(store.data.logins.length, 1);
+  Assert.deepEqual(store.data.logins[0], {
+    id: 1,
+    hostname: "http://www.example.com",
+    httpRealm: null,
+    formSubmitURL: "http://www.example.com",
+    usernameField: "usernameField",
+    passwordField: "passwordField",
+    encryptedUsername: "(test)",
+    encryptedPassword: "(test)",
+    guid: "(test)",
+    encType: Ci.nsILoginManagerCrypto.ENCTYPE_SDR,
+    timeCreated: 1262304000000,
+    timeLastUsed: 1262390400000,
+    timePasswordChanged: 1262476800000,
+    timesUsed: 1,
+  });
+});
+
+/**
+ * Loads login data from a malformed JSON string.
+ */
+add_task(async function test_load_string_malformed() {
+  let store = new LoginStore(getTempFile(TEST_STORE_FILE_NAME).path);
+
+  let string = '{"logins":[{"hostname":"http://www.example.com","id":1,';
+
+  await IOUtils.writeUTF8(store.path, string, {
+    tmpPath: store.path + ".tmp",
+  });
+
+  await store.load();
+
+  // A backup file should have been created.
+  Assert.ok(await IOUtils.exists(store.path + ".corrupt"));
+  await IOUtils.remove(store.path + ".corrupt");
+
+  // The store should be ready to accept new data.
+  Assert.equal(store.data.logins.length, 0);
+});
+
+/**
+ * Loads login data from a malformed JSON string, using the synchronous
+ * initialization path.
+ */
+add_task(async function test_load_string_malformed_sync() {
+  let store = new LoginStore(getTempFile(TEST_STORE_FILE_NAME).path);
+
+  let string = '{"logins":[{"hostname":"http://www.example.com","id":1,';
+
+  await IOUtils.writeUTF8(store.path, string, {
+    tmpPath: store.path + ".tmp",
+  });
+
+  store.ensureDataReady();
+
+  // A backup file should have been created.
+  Assert.ok(await IOUtils.exists(store.path + ".corrupt"));
+  await IOUtils.remove(store.path + ".corrupt");
+
+  // The store should be ready to accept new data.
+  Assert.equal(store.data.logins.length, 0);
+});
+
+/**
+ * Fix bad dates when loading login data
+ */
+add_task(async function test_load_bad_dates() {
+  let rawLoginData = {
+    encType: 1,
+    encryptedPassword: "(test)",
+    encryptedUsername: "(test)",
+    formSubmitURL: "https://www.example.com",
+    guid: "{2a97313f-873b-4048-9a3d-4f442b46c1e5}",
+    hostname: "https://www.example.com",
+    httpRealm: null,
+    id: 1,
+    passwordField: "pass",
+    timesUsed: 1,
+    usernameField: "email",
+  };
+  let rawStoreData = {
+    dismissedBreachAlertsByLoginGUID: {},
+    logins: [],
+    nextId: 2,
+    potentiallyVulnerablePasswords: [],
+    version: 2,
+  };
+
+  /**
+   * test that:
+   * - bogus (0 or out-of-range) date values in any of the date fields are replaced with the
+   *   earliest time marked by the other date fields
+   * - bogus bogus (0 or out-of-range) date values in all date fields are replaced with the time of import
+   */
+  let tests = [
+    {
+      name: "Out-of-range time values",
+      savedProps: {
+        timePasswordChanged: MAX_DATE_MS + 1,
+        timeLastUsed: MAX_DATE_MS + 1,
+        timeCreated: MAX_DATE_MS + 1,
+      },
+      expectedProps: {
+        timePasswordChanged: "now",
+        timeLastUsed: "now",
+        timeCreated: "now",
+      },
+    },
+    {
+      name: "All zero time values",
+      savedProps: {
+        timePasswordChanged: 0,
+        timeLastUsed: 0,
+        timeCreated: 0,
+      },
+      expectedProps: {
+        timePasswordChanged: "now",
+        timeLastUsed: "now",
+        timeCreated: "now",
+      },
+    },
+    {
+      name: "Only timeCreated has value",
+      savedProps: {
+        timePasswordChanged: 0,
+        timeLastUsed: 0,
+        timeCreated: 946713600000,
+      },
+      expectedProps: {
+        timePasswordChanged: 946713600000,
+        timeLastUsed: 946713600000,
+        timeCreated: 946713600000,
+      },
+    },
+    {
+      name: "timeCreated has 0 value",
+      savedProps: {
+        timePasswordChanged: 946713600000,
+        timeLastUsed: 946713600000,
+        timeCreated: 0,
+      },
+      expectedProps: {
+        timePasswordChanged: 946713600000,
+        timeLastUsed: 946713600000,
+        timeCreated: 946713600000,
+      },
+    },
+    {
+      name: "timeCreated has out-of-range value",
+      savedProps: {
+        timePasswordChanged: 946713600000,
+        timeLastUsed: 946713600000,
+        timeCreated: MAX_DATE_MS + 1,
+      },
+      expectedProps: {
+        timePasswordChanged: 946713600000,
+        timeLastUsed: 946713600000,
+        timeCreated: 946713600000,
+      },
+    },
+    {
+      name: "Use earliest time for missing value",
+      savedProps: {
+        timePasswordChanged: 0,
+        timeLastUsed: 946713600000,
+        timeCreated: 946540800000,
+      },
+      expectedProps: {
+        timePasswordChanged: 946540800000,
+        timeLastUsed: 946713600000,
+        timeCreated: 946540800000,
+      },
+    },
+  ];
+
+  for (let testData of tests) {
+    let store = new LoginStore(getTempFile(TEST_STORE_FILE_NAME).path);
+    let string = JSON.stringify(
+      Object.assign({}, rawStoreData, {
+        logins: [Object.assign({}, rawLoginData, testData.savedProps)],
+      })
+    );
+    await IOUtils.writeUTF8(store.path, string, {
+      tmpPath: store.path + ".tmp",
+    });
+    let now = Date.now();
+    await store.load();
+
+    Assert.equal(
+      store.data.logins.length,
+      1,
+      `${testData.name}: Expected a single login`
+    );
+
+    let login = store.data.logins[0];
+    for (let pname of ["timeCreated", "timeLastUsed", "timePasswordChanged"]) {
+      if (testData.expectedProps[pname] === "now") {
+        Assert.ok(
+          login[pname] >= now,
+          `${testData.name}: Check ${pname} is at/near now`
+        );
+      } else {
+        Assert.equal(
+          login[pname],
+          testData.expectedProps[pname],
+          `${testData.name}: Check expected ${pname}`
+        );
+      }
+    }
+    Assert.equal(store.data.version, 3, "Check version was bumped");
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_notifications.js b/toolkit/components/passwordmgr/test/unit/test_notifications.js
new file mode 100644
index 0000000000..3ada39d246
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_notifications.js
@@ -0,0 +1,193 @@
+/**
+ * Tests notifications dispatched when modifying stored logins.
+ */
+
+let expectedNotification;
+let expectedData;
+
+let TestObserver = {
+  QueryInterface: ChromeUtils.generateQI([
+    "nsIObserver",
+    "nsISupportsWeakReference",
+  ]),
+
+  observe(subject, topic, data) {
+    Assert.equal(topic, "passwordmgr-storage-changed");
+    Assert.equal(data, expectedNotification);
+
+    switch (data) {
+      case "addLogin":
+        Assert.ok(subject instanceof Ci.nsILoginInfo);
+        Assert.ok(subject instanceof Ci.nsILoginMetaInfo);
+        Assert.ok(expectedData.equals(subject)); // nsILoginInfo.equals()
+        break;
+      case "modifyLogin":
+        Assert.ok(subject instanceof Ci.nsIArray);
+        Assert.equal(subject.length, 2);
+        let oldLogin = subject.queryElementAt(0, Ci.nsILoginInfo);
+        let newLogin = subject.queryElementAt(1, Ci.nsILoginInfo);
+        Assert.ok(expectedData[0].equals(oldLogin)); // nsILoginInfo.equals()
+        Assert.ok(expectedData[1].equals(newLogin));
+        break;
+      case "removeLogin":
+        Assert.ok(subject instanceof Ci.nsILoginInfo);
+        Assert.ok(subject instanceof Ci.nsILoginMetaInfo);
+        Assert.ok(expectedData.equals(subject)); // nsILoginInfo.equals()
+        break;
+      case "removeAllLogins":
+        Assert.ok(subject instanceof Ci.nsIArray);
+        break;
+      case "hostSavingEnabled":
+      case "hostSavingDisabled":
+        Assert.ok(subject instanceof Ci.nsISupportsString);
+        Assert.equal(subject.data, expectedData);
+        break;
+      default:
+        do_throw("Unhandled notification: " + data + " / " + topic);
+    }
+
+    expectedNotification = null; // ensure a duplicate is flagged as unexpected.
+    expectedData = null;
+  },
+};
+
+add_task(async function test_notifications() {
+  let testnum = 0;
+  let testdesc = "Setup of nsLoginInfo test-users";
+
+  try {
+    let testuser1 = new LoginInfo(
+      "http://testhost1",
+      "",
+      null,
+      "dummydude",
+      "itsasecret",
+      "put_user_here",
+      "put_pw_here"
+    );
+
+    let testuser2 = new LoginInfo(
+      "http://testhost2",
+      "",
+      null,
+      "dummydude2",
+      "itsasecret2",
+      "put_user2_here",
+      "put_pw2_here"
+    );
+
+    Services.obs.addObserver(TestObserver, "passwordmgr-storage-changed");
+
+    /* ========== 1 ========== */
+    testnum = 1;
+    testdesc = "Initial connection to storage module";
+
+    /* ========== 2 ========== */
+    testnum++;
+    testdesc = "addLogin";
+
+    expectedNotification = "addLogin";
+    expectedData = testuser1;
+    await Services.logins.addLoginAsync(testuser1);
+    await LoginTestUtils.checkLogins([testuser1]);
+    Assert.equal(expectedNotification, null); // check that observer got a notification
+
+    /* ========== 3 ========== */
+    testnum++;
+    testdesc = "modifyLogin";
+
+    expectedNotification = "modifyLogin";
+    expectedData = [testuser1, testuser2];
+    Services.logins.modifyLogin(testuser1, testuser2);
+    Assert.equal(expectedNotification, null);
+    await LoginTestUtils.checkLogins([testuser2]);
+
+    /* ========== 4 ========== */
+    testnum++;
+    testdesc = "removeLogin";
+
+    expectedNotification = "removeLogin";
+    expectedData = testuser2;
+    Services.logins.removeLogin(testuser2);
+    Assert.equal(expectedNotification, null);
+    await LoginTestUtils.checkLogins([]);
+
+    /* ========== 5 ========== */
+    testnum++;
+    testdesc = "removeAllLogins";
+
+    expectedNotification = "removeAllLogins";
+    expectedData = null;
+    Services.logins.removeAllLogins();
+    Assert.equal(expectedNotification, null);
+    await LoginTestUtils.checkLogins([]);
+
+    /* ========== 6 ========== */
+    testnum++;
+    testdesc = "removeAllLogins (again)";
+
+    expectedNotification = "addLogin";
+    expectedData = testuser1;
+    await Services.logins.addLoginAsync(testuser1);
+
+    expectedNotification = "removeAllLogins";
+    expectedData = null;
+    Services.logins.removeAllLogins();
+    Assert.equal(expectedNotification, null);
+    await LoginTestUtils.checkLogins([]);
+
+    /* ========== 7 ========== */
+    testnum++;
+    testdesc = "setLoginSavingEnabled / false";
+
+    expectedNotification = "hostSavingDisabled";
+    expectedData = "http://site.com";
+    Services.logins.setLoginSavingEnabled("http://site.com", false);
+    Assert.equal(expectedNotification, null);
+    LoginTestUtils.assertDisabledHostsEqual(
+      Services.logins.getAllDisabledHosts(),
+      ["http://site.com"]
+    );
+
+    /* ========== 8 ========== */
+    testnum++;
+    testdesc = "setLoginSavingEnabled / false (again)";
+
+    expectedNotification = "hostSavingDisabled";
+    expectedData = "http://site.com";
+    Services.logins.setLoginSavingEnabled("http://site.com", false);
+    Assert.equal(expectedNotification, null);
+    LoginTestUtils.assertDisabledHostsEqual(
+      Services.logins.getAllDisabledHosts(),
+      ["http://site.com"]
+    );
+
+    /* ========== 9 ========== */
+    testnum++;
+    testdesc = "setLoginSavingEnabled / true";
+
+    expectedNotification = "hostSavingEnabled";
+    expectedData = "http://site.com";
+    Services.logins.setLoginSavingEnabled("http://site.com", true);
+    Assert.equal(expectedNotification, null);
+    await LoginTestUtils.checkLogins([]);
+
+    /* ========== 10 ========== */
+    testnum++;
+    testdesc = "setLoginSavingEnabled / true (again)";
+
+    expectedNotification = "hostSavingEnabled";
+    expectedData = "http://site.com";
+    Services.logins.setLoginSavingEnabled("http://site.com", true);
+    Assert.equal(expectedNotification, null);
+    await LoginTestUtils.checkLogins([]);
+
+    Services.obs.removeObserver(TestObserver, "passwordmgr-storage-changed");
+
+    LoginTestUtils.clearData();
+  } catch (e) {
+    throw new Error(
+      "FAILED in test #" + testnum + " -- " + testdesc + ": " + e
+    );
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_recipes_add.js b/toolkit/components/passwordmgr/test/unit/test_recipes_add.js
new file mode 100644
index 0000000000..253556232e
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_recipes_add.js
@@ -0,0 +1,288 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests adding and retrieving LoginRecipes in the parent process.
+ */
+
+"use strict";
+
+add_task(async function test_init() {
+  let parent = new LoginRecipesParent({ defaults: null });
+  let initPromise1 = parent.initializationPromise;
+  let initPromise2 = parent.initializationPromise;
+  Assert.strictEqual(
+    initPromise1,
+    initPromise2,
+    "Check that the same promise is returned"
+  );
+
+  let recipesParent = await initPromise1;
+  Assert.ok(
+    recipesParent instanceof LoginRecipesParent,
+    "Check init return value"
+  );
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    0,
+    "Initially 0 recipes"
+  );
+});
+
+add_task(async function test_get_missing_host() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  let exampleRecipes = recipesParent.getRecipesForHost("example.invalid");
+  Assert.strictEqual(
+    exampleRecipes.size,
+    0,
+    "Check recipe count for example.invalid"
+  );
+});
+
+add_task(async function test_add_get_simple_host() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    0,
+    "Initially 0 recipes"
+  );
+  recipesParent.add({
+    hosts: ["example.com"],
+  });
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    1,
+    "Check number of hosts after the addition"
+  );
+
+  let exampleRecipes = recipesParent.getRecipesForHost("example.com");
+  Assert.strictEqual(
+    exampleRecipes.size,
+    1,
+    "Check recipe count for example.com"
+  );
+  let recipe = [...exampleRecipes][0];
+  Assert.strictEqual(typeof recipe, "object", "Check recipe type");
+  Assert.strictEqual(recipe.hosts.length, 1, "Check that one host is present");
+  Assert.strictEqual(recipe.hosts[0], "example.com", "Check the one host");
+});
+
+add_task(async function test_add_get_non_standard_port_host() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  recipesParent.add({
+    hosts: ["example.com:8080"],
+  });
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    1,
+    "Check number of hosts after the addition"
+  );
+
+  let exampleRecipes = recipesParent.getRecipesForHost("example.com:8080");
+  Assert.strictEqual(
+    exampleRecipes.size,
+    1,
+    "Check recipe count for example.com:8080"
+  );
+  let recipe = [...exampleRecipes][0];
+  Assert.strictEqual(typeof recipe, "object", "Check recipe type");
+  Assert.strictEqual(recipe.hosts.length, 1, "Check that one host is present");
+  Assert.strictEqual(recipe.hosts[0], "example.com:8080", "Check the one host");
+});
+
+add_task(async function test_add_multiple_hosts() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  recipesParent.add({
+    hosts: ["example.com", "foo.invalid"],
+  });
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    2,
+    "Check number of hosts after the addition"
+  );
+
+  let exampleRecipes = recipesParent.getRecipesForHost("example.com");
+  Assert.strictEqual(
+    exampleRecipes.size,
+    1,
+    "Check recipe count for example.com"
+  );
+  let recipe = [...exampleRecipes][0];
+  Assert.strictEqual(typeof recipe, "object", "Check recipe type");
+  Assert.strictEqual(
+    recipe.hosts.length,
+    2,
+    "Check that two hosts are present"
+  );
+  Assert.strictEqual(recipe.hosts[0], "example.com", "Check the first host");
+  Assert.strictEqual(recipe.hosts[1], "foo.invalid", "Check the second host");
+
+  let fooRecipes = recipesParent.getRecipesForHost("foo.invalid");
+  Assert.strictEqual(fooRecipes.size, 1, "Check recipe count for foo.invalid");
+  let fooRecipe = [...fooRecipes][0];
+  Assert.strictEqual(fooRecipe, recipe, "Check that the recipe is shared");
+  Assert.strictEqual(typeof fooRecipe, "object", "Check recipe type");
+  Assert.strictEqual(
+    fooRecipe.hosts.length,
+    2,
+    "Check that two hosts are present"
+  );
+  Assert.strictEqual(fooRecipe.hosts[0], "example.com", "Check the first host");
+  Assert.strictEqual(
+    fooRecipe.hosts[1],
+    "foo.invalid",
+    "Check the second host"
+  );
+});
+
+add_task(async function test_add_pathRegex() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  recipesParent.add({
+    hosts: ["example.com"],
+    pathRegex: /^\/mypath\//,
+  });
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    1,
+    "Check number of hosts after the addition"
+  );
+
+  let exampleRecipes = recipesParent.getRecipesForHost("example.com");
+  Assert.strictEqual(
+    exampleRecipes.size,
+    1,
+    "Check recipe count for example.com"
+  );
+  let recipe = [...exampleRecipes][0];
+  Assert.strictEqual(typeof recipe, "object", "Check recipe type");
+  Assert.strictEqual(recipe.hosts.length, 1, "Check that one host is present");
+  Assert.strictEqual(recipe.hosts[0], "example.com", "Check the one host");
+  Assert.strictEqual(
+    recipe.pathRegex.toString(),
+    "/^\\/mypath\\//",
+    "Check the pathRegex"
+  );
+});
+
+add_task(async function test_add_selectors() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  recipesParent.add({
+    hosts: ["example.com"],
+    usernameSelector: "#my-username",
+    passwordSelector: "#my-form > input.password",
+  });
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    1,
+    "Check number of hosts after the addition"
+  );
+
+  let exampleRecipes = recipesParent.getRecipesForHost("example.com");
+  Assert.strictEqual(
+    exampleRecipes.size,
+    1,
+    "Check recipe count for example.com"
+  );
+  let recipe = [...exampleRecipes][0];
+  Assert.strictEqual(typeof recipe, "object", "Check recipe type");
+  Assert.strictEqual(recipe.hosts.length, 1, "Check that one host is present");
+  Assert.strictEqual(recipe.hosts[0], "example.com", "Check the one host");
+  Assert.strictEqual(
+    recipe.usernameSelector,
+    "#my-username",
+    "Check the usernameSelector"
+  );
+  Assert.strictEqual(
+    recipe.passwordSelector,
+    "#my-form > input.password",
+    "Check the passwordSelector"
+  );
+});
+
+/* Begin checking errors with add */
+
+add_task(async function test_add_missing_prop() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  Assert.throws(
+    () => recipesParent.add({}),
+    /required/,
+    "Some properties are required"
+  );
+});
+
+add_task(async function test_add_unknown_prop() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  Assert.throws(
+    () =>
+      recipesParent.add({
+        unknownProp: true,
+      }),
+    /supported/,
+    "Unknown properties should cause an error to help with typos"
+  );
+});
+
+add_task(async function test_add_invalid_hosts() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  Assert.throws(
+    () =>
+      recipesParent.add({
+        hosts: 404,
+      }),
+    /array/,
+    "hosts should be an array"
+  );
+});
+
+add_task(async function test_add_empty_host_array() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  Assert.throws(
+    () =>
+      recipesParent.add({
+        hosts: [],
+      }),
+    /array/,
+    "hosts should be a non-empty array"
+  );
+});
+
+add_task(async function test_add_pathRegex_non_regexp() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  Assert.throws(
+    () =>
+      recipesParent.add({
+        hosts: ["example.com"],
+        pathRegex: "foo",
+      }),
+    /regular expression/,
+    "pathRegex should be a RegExp"
+  );
+});
+
+add_task(async function test_add_usernameSelector_non_string() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  Assert.throws(
+    () =>
+      recipesParent.add({
+        hosts: ["example.com"],
+        usernameSelector: 404,
+      }),
+    /string/,
+    "usernameSelector should be a string"
+  );
+});
+
+add_task(async function test_add_passwordSelector_non_string() {
+  let recipesParent = await RecipeHelpers.initNewParent();
+  Assert.throws(
+    () =>
+      recipesParent.add({
+        hosts: ["example.com"],
+        passwordSelector: 404,
+      }),
+    /string/,
+    "passwordSelector should be a string"
+  );
+});
+
+/* End checking errors with add */
diff --git a/toolkit/components/passwordmgr/test/unit/test_recipes_content.js b/toolkit/components/passwordmgr/test/unit/test_recipes_content.js
new file mode 100644
index 0000000000..673bb50851
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_recipes_content.js
@@ -0,0 +1,53 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Test filtering recipes in LoginRecipesContent.
+ */
+
+"use strict";
+
+add_task(async function test_getFieldOverrides() {
+  let recipes = new Set([
+    {
+      // path doesn't match but otherwise good
+      hosts: ["example.com:8080"],
+      passwordSelector: "#password",
+      pathRegex: /^\/$/,
+      usernameSelector: ".username",
+    },
+    {
+      // match with no field overrides
+      hosts: ["example.com:8080"],
+    },
+    {
+      // best match (field selectors + path match)
+      description: "best match",
+      hosts: ["a.invalid", "example.com:8080", "other.invalid"],
+      passwordSelector: "#password",
+      pathRegex: /^\/first\/second\/$/,
+      usernameSelector: ".username",
+    },
+  ]);
+
+  let form = MockDocument.createTestDocument(
+    "http://localhost:8080/first/second/",
+    "<form>"
+  ).forms[0];
+  let override = LoginRecipesContent.getFieldOverrides(recipes, form);
+  Assert.strictEqual(
+    override.description,
+    "best match",
+    "Check the best field override recipe was returned"
+  );
+  Assert.strictEqual(
+    override.usernameSelector,
+    ".username",
+    "Check usernameSelector"
+  );
+  Assert.strictEqual(
+    override.passwordSelector,
+    "#password",
+    "Check passwordSelector"
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_remote_recipes.js b/toolkit/components/passwordmgr/test/unit/test_remote_recipes.js
new file mode 100644
index 0000000000..7d16e205e9
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_remote_recipes.js
@@ -0,0 +1,162 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests retrieving remote LoginRecipes in the parent process.
+ * See https://firefox-source-docs.mozilla.org/services/settings/#unit-tests for explanation of db.importChanges({}, Date.now());
+ */
+
+"use strict";
+
+const { RemoteSettings } = ChromeUtils.importESModule(
+  "resource://services-settings/remote-settings.sys.mjs"
+);
+
+const REMOTE_SETTINGS_COLLECTION = "password-recipes";
+
+add_task(async function test_init_remote_recipe() {
+  const db = RemoteSettings(REMOTE_SETTINGS_COLLECTION).db;
+  await db.clear();
+  const record1 = {
+    id: "some-fake-ID",
+    hosts: ["www.testDomain.com"],
+    description: "Some description here",
+    usernameSelector: "#username",
+  };
+  await db.importChanges({}, Date.now(), [record1], { clear: true });
+  let parent = new LoginRecipesParent({ defaults: true });
+
+  let recipesParent = await parent.initializationPromise;
+  Assert.ok(
+    recipesParent instanceof LoginRecipesParent,
+    "Check initialization promise value which should be an instance of LoginRecipesParent"
+  );
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    1,
+    "Initially 1 recipe based on our test record"
+  );
+  let rsClient = recipesParent._rsClient;
+
+  recipesParent.reset();
+  await recipesParent.initializationPromise;
+  Assert.ok(
+    recipesParent instanceof LoginRecipesParent,
+    "Ensure that the instance of LoginRecipesParent has not changed after resetting"
+  );
+  Assert.strictEqual(
+    rsClient,
+    recipesParent._rsClient,
+    "Resetting recipes should not modify the rs client"
+  );
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    1,
+    "Initially 1 recipe based on our test record"
+  );
+  await db.clear();
+  await db.importChanges({}, 42);
+});
+
+add_task(async function test_add_recipe_sync() {
+  const db = RemoteSettings(REMOTE_SETTINGS_COLLECTION).db;
+  const record1 = {
+    id: "some-fake-ID",
+    hosts: ["www.testDomain.com"],
+    description: "Some description here",
+    usernameSelector: "#username",
+  };
+  await db.importChanges({}, Date.now(), [record1], { clear: true });
+  let parent = new LoginRecipesParent({ defaults: true });
+  let recipesParent = await parent.initializationPromise;
+
+  const record2 = {
+    id: "some-fake-ID-2",
+    hosts: ["www.testDomain2.com"],
+    description: "Some description here. Wow it changed!",
+    usernameSelector: "#username",
+  };
+  const payload = {
+    current: [record1, record2],
+    created: [record2],
+    updated: [],
+    deleted: [],
+  };
+  await RemoteSettings(REMOTE_SETTINGS_COLLECTION).emit("sync", {
+    data: payload,
+  });
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    2,
+    "New recipe from sync event added successfully"
+  );
+  await db.clear();
+  await db.importChanges({}, 42);
+});
+
+add_task(async function test_remove_recipe_sync() {
+  const db = RemoteSettings(REMOTE_SETTINGS_COLLECTION).db;
+  const record1 = {
+    id: "some-fake-ID",
+    hosts: ["www.testDomain.com"],
+    description: "Some description here",
+    usernameSelector: "#username",
+  };
+  await db.importChanges({}, Date.now(), [record1], { clear: true });
+  let parent = new LoginRecipesParent({ defaults: true });
+  let recipesParent = await parent.initializationPromise;
+
+  const deletePayload = {
+    current: [],
+    created: [],
+    updated: [],
+    deleted: [record1],
+  };
+  await RemoteSettings(REMOTE_SETTINGS_COLLECTION).emit("sync", {
+    data: deletePayload,
+  });
+  Assert.strictEqual(
+    recipesParent._recipesByHost.size,
+    0,
+    "Recipes successfully deleted on sync event"
+  );
+  await db.clear();
+});
+
+add_task(async function test_malformed_recipes_in_db() {
+  const db = RemoteSettings(REMOTE_SETTINGS_COLLECTION).db;
+  const malformedRecord = {
+    id: "some-ID",
+    hosts: ["www.testDomain.com"],
+    description: "Some description here",
+    usernameSelector: "#username",
+    fieldThatDoesNotExist: "value",
+  };
+  await db.importChanges({}, Date.now(), [malformedRecord], { clear: true });
+  let parent = new LoginRecipesParent({ defaults: true });
+  try {
+    await parent.initializationPromise;
+  } catch (e) {
+    Assert.ok(
+      e == "There were 1 recipe error(s)",
+      "It should throw an error because of field that does not match the schema"
+    );
+  }
+
+  await db.clear();
+  const missingHostsRecord = {
+    id: "some-ID",
+    description: "Some description here",
+    usernameSelector: "#username",
+  };
+  await db.importChanges({}, Date.now(), [missingHostsRecord], { clear: true });
+  parent = new LoginRecipesParent({ defaults: true });
+  try {
+    await parent.initializationPromise;
+  } catch (e) {
+    Assert.ok(
+      e == "There were 1 recipe error(s)",
+      "It should throw an error because of missing hosts field"
+    );
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_search_schemeUpgrades.js b/toolkit/components/passwordmgr/test/unit/test_search_schemeUpgrades.js
new file mode 100644
index 0000000000..9428d3f897
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_search_schemeUpgrades.js
@@ -0,0 +1,239 @@
+/**
+ * Test Services.logins.searchLogins with the `schemeUpgrades` property.
+ */
+
+const HTTP3_ORIGIN = "http://www3.example.com";
+const HTTPS_ORIGIN = "https://www.example.com";
+const HTTP_ORIGIN = "http://www.example.com";
+
+/**
+ * Returns a list of new nsILoginInfo objects that are a subset of the test
+ * data, built to match the specified query.
+ *
+ * @param {Object} aQuery
+ *        Each property and value of this object restricts the search to those
+ *        entries from the test data that match the property exactly.
+ */
+function buildExpectedLogins(aQuery) {
+  return TestData.loginList().filter(entry =>
+    Object.keys(aQuery).every(name => {
+      if (name == "schemeUpgrades") {
+        return true;
+      }
+      if (["origin", "formActionOrigin"].includes(name)) {
+        return LoginHelper.isOriginMatching(entry[name], aQuery[name], {
+          schemeUpgrades: aQuery.schemeUpgrades,
+        });
+      }
+      return entry[name] === aQuery[name];
+    })
+  );
+}
+
+/**
+ * Tests the searchLogins function.
+ *
+ * @param {Object} aQuery
+ *        Each property and value of this object is translated to an entry in
+ *        the nsIPropertyBag parameter of searchLogins.
+ * @param {Number} aExpectedCount
+ *        Number of logins from the test data that should be found.  The actual
+ *        list of logins is obtained using the buildExpectedLogins helper, and
+ *        this value is just used to verify that modifications to the test data
+ *        don't make the current test meaningless.
+ */
+function checkSearch(aQuery, aExpectedCount) {
+  info("Testing searchLogins for " + JSON.stringify(aQuery));
+
+  let expectedLogins = buildExpectedLogins(aQuery);
+  Assert.equal(expectedLogins.length, aExpectedCount);
+
+  let logins = Services.logins.searchLogins(newPropertyBag(aQuery));
+  LoginTestUtils.assertLoginListsEqual(logins, expectedLogins);
+}
+
+/**
+ * Prepare data for the following tests.
+ */
+add_setup(async () => {
+  await Services.logins.addLogins(TestData.loginList());
+});
+
+/**
+ * Tests searchLogins with the `schemeUpgrades` property
+ */
+add_task(function test_search_schemeUpgrades_origin() {
+  // Origin-only
+  checkSearch(
+    {
+      origin: HTTPS_ORIGIN,
+    },
+    1
+  );
+  checkSearch(
+    {
+      origin: HTTPS_ORIGIN,
+      schemeUpgrades: false,
+    },
+    1
+  );
+  checkSearch(
+    {
+      origin: HTTPS_ORIGIN,
+      schemeUpgrades: undefined,
+    },
+    1
+  );
+  checkSearch(
+    {
+      origin: HTTPS_ORIGIN,
+      schemeUpgrades: true,
+    },
+    2
+  );
+});
+
+/**
+ * Same as above but replacing origin with formActionOrigin.
+ */
+add_task(function test_search_schemeUpgrades_formActionOrigin() {
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+    },
+    2
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      schemeUpgrades: false,
+    },
+    2
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      schemeUpgrades: undefined,
+    },
+    2
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      schemeUpgrades: true,
+    },
+    4
+  );
+});
+
+add_task(function test_search_schemeUpgrades_origin_formActionOrigin() {
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      origin: HTTPS_ORIGIN,
+    },
+    1
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      origin: HTTPS_ORIGIN,
+      schemeUpgrades: false,
+    },
+    1
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      origin: HTTPS_ORIGIN,
+      schemeUpgrades: undefined,
+    },
+    1
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      origin: HTTPS_ORIGIN,
+      schemeUpgrades: true,
+    },
+    2
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      origin: HTTPS_ORIGIN,
+      schemeUpgrades: true,
+      usernameField: "form_field_username",
+    },
+    2
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      origin: HTTPS_ORIGIN,
+      passwordField: "form_field_password",
+      schemeUpgrades: true,
+      usernameField: "form_field_username",
+    },
+    2
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      origin: HTTPS_ORIGIN,
+      httpRealm: null,
+      passwordField: "form_field_password",
+      schemeUpgrades: true,
+      usernameField: "form_field_username",
+    },
+    2
+  );
+});
+
+/**
+ * HTTP submitting to HTTPS
+ */
+add_task(function test_http_to_https() {
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      origin: HTTP3_ORIGIN,
+      httpRealm: null,
+      schemeUpgrades: false,
+    },
+    1
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTPS_ORIGIN,
+      origin: HTTP3_ORIGIN,
+      httpRealm: null,
+      schemeUpgrades: true,
+    },
+    2
+  );
+});
+
+/**
+ * schemeUpgrades shouldn't cause downgrades
+ */
+add_task(function test_search_schemeUpgrades_downgrade() {
+  checkSearch(
+    {
+      formActionOrigin: HTTP_ORIGIN,
+      origin: HTTP_ORIGIN,
+    },
+    1
+  );
+  info(
+    "The same number should be found with schemeUpgrades since we're searching for HTTP"
+  );
+  checkSearch(
+    {
+      formActionOrigin: HTTP_ORIGIN,
+      origin: HTTP_ORIGIN,
+      schemeUpgrades: true,
+    },
+    1
+  );
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_shadowHTTPLogins.js b/toolkit/components/passwordmgr/test/unit/test_shadowHTTPLogins.js
new file mode 100644
index 0000000000..86a9a08ac3
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_shadowHTTPLogins.js
@@ -0,0 +1,82 @@
+/**
+ * Test LoginHelper.shadowHTTPLogins
+ */
+
+"use strict";
+
+const DOMAIN1_HTTP_TO_HTTP_U1_P1 = TestData.formLogin({});
+const DOMAIN1_HTTP_TO_HTTP_U2_P1 = TestData.formLogin({
+  username: "user2",
+});
+const DOMAIN1_HTTPS_TO_HTTPS_U1_P1 = TestData.formLogin({
+  origin: "https://www3.example.com",
+  formActionOrigin: "https://login.example.com",
+});
+const DOMAIN1_HTTPS_TO_HTTPS_U1_P2 = TestData.formLogin({
+  origin: "https://www3.example.com",
+  formActionOrigin: "https://login.example.com",
+  password: "password two",
+});
+const DOMAIN1_HTTP_TO_HTTP_U1_P2 = TestData.formLogin({
+  password: "password two",
+});
+const DOMAIN1_HTTP_TO_HTTP_U1_P1_DIFFERENT_PORT = TestData.formLogin({
+  origin: "http://www3.example.com:8080",
+});
+const DOMAIN2_HTTP_TO_HTTP_U1_P1 = TestData.formLogin({
+  origin: "http://different.example.com",
+});
+
+add_task(function test_shadowHTTPLogins() {
+  let testcases = [
+    {
+      description: "same hostPort, same username, different scheme",
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P1],
+      expected: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1],
+    },
+    {
+      description: "different passwords, different scheme",
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U1_P2],
+      expected: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1],
+    },
+    {
+      description: "both https, same username, different password",
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTPS_TO_HTTPS_U1_P2],
+      expected: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTPS_TO_HTTPS_U1_P2],
+    },
+    {
+      description: "same origin, different port, different scheme",
+      logins: [
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P1,
+        DOMAIN1_HTTP_TO_HTTP_U1_P1_DIFFERENT_PORT,
+      ],
+      expected: [
+        DOMAIN1_HTTPS_TO_HTTPS_U1_P1,
+        DOMAIN1_HTTP_TO_HTTP_U1_P1_DIFFERENT_PORT,
+      ],
+    },
+    {
+      description: "different origin, different scheme",
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN2_HTTP_TO_HTTP_U1_P1],
+      expected: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN2_HTTP_TO_HTTP_U1_P1],
+    },
+    {
+      description: "different username, different scheme",
+      logins: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U2_P1],
+      expected: [DOMAIN1_HTTPS_TO_HTTPS_U1_P1, DOMAIN1_HTTP_TO_HTTP_U2_P1],
+    },
+  ];
+
+  for (let tc of testcases) {
+    info(tc.description);
+    let actual = LoginHelper.shadowHTTPLogins(tc.logins);
+    Assert.strictEqual(
+      actual.length,
+      tc.expected.length,
+      `Check result length`
+    );
+    for (let [i, login] of tc.expected.entries()) {
+      Assert.strictEqual(actual[i], login, `Check index ${i}`);
+    }
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_storage.js b/toolkit/components/passwordmgr/test/unit/test_storage.js
new file mode 100644
index 0000000000..55bbe9d371
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_storage.js
@@ -0,0 +1,93 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests that the default storage module attached to the Login
+ * Manager service is able to save and reload nsILoginInfo properties correctly,
+ * even when they include special characters.
+ */
+
+"use strict";
+
+// Globals
+
+async function reloadAndCheckLoginsGen(aExpectedLogins) {
+  await LoginTestUtils.reloadData();
+  await LoginTestUtils.checkLogins(aExpectedLogins);
+  LoginTestUtils.clearData();
+}
+
+// Tests
+
+/**
+ * Tests addLogin with valid non-ASCII characters.
+ */
+add_task(async function test_storage_addLogin_nonascii() {
+  let origin = "http://" + String.fromCharCode(355) + ".example.com";
+
+  // Store the strings "user" and "pass" using similarly looking glyphs.
+  let loginInfo = TestData.formLogin({
+    origin,
+    formActionOrigin: origin,
+    username: String.fromCharCode(533, 537, 7570, 345),
+    password: String.fromCharCode(421, 259, 349, 537),
+    usernameField: "field_" + String.fromCharCode(533, 537, 7570, 345),
+    passwordField: "field_" + String.fromCharCode(421, 259, 349, 537),
+  });
+  await Services.logins.addLoginAsync(loginInfo);
+  await reloadAndCheckLoginsGen([loginInfo]);
+
+  // Store the string "test" using similarly looking glyphs.
+  loginInfo = TestData.authLogin({
+    httpRealm: String.fromCharCode(355, 277, 349, 357),
+  });
+  await Services.logins.addLoginAsync(loginInfo);
+  await reloadAndCheckLoginsGen([loginInfo]);
+});
+
+/**
+ * Tests addLogin with newline characters in the username and password.
+ */
+add_task(async function test_storage_addLogin_newlines() {
+  let loginInfo = TestData.formLogin({
+    username: "user\r\nname",
+    password: "password\r\n",
+  });
+  await Services.logins.addLoginAsync(loginInfo);
+  await reloadAndCheckLoginsGen([loginInfo]);
+});
+
+/**
+ * Tests addLogin with a single dot in fields where it is allowed.
+ *
+ * These tests exist to verify the legacy "signons.txt" storage format.
+ */
+add_task(async function test_storage_addLogin_dot() {
+  let loginInfo = TestData.formLogin({ origin: ".", passwordField: "." });
+  await Services.logins.addLoginAsync(loginInfo);
+  await reloadAndCheckLoginsGen([loginInfo]);
+
+  loginInfo = TestData.authLogin({ httpRealm: "." });
+  await Services.logins.addLoginAsync(loginInfo);
+  await reloadAndCheckLoginsGen([loginInfo]);
+});
+
+/**
+ * Tests addLogin with parentheses in origins.
+ *
+ * These tests exist to verify the legacy "signons.txt" storage format.
+ */
+add_task(async function test_storage_addLogin_parentheses() {
+  let loginList = [
+    TestData.authLogin({ httpRealm: "(realm" }),
+    TestData.authLogin({ httpRealm: "realm)" }),
+    TestData.authLogin({ httpRealm: "(realm)" }),
+    TestData.authLogin({ httpRealm: ")realm(" }),
+    TestData.authLogin({ origin: "http://parens(.example.com" }),
+    TestData.authLogin({ origin: "http://parens).example.com" }),
+    TestData.authLogin({ origin: "http://parens(example).example.com" }),
+    TestData.authLogin({ origin: "http://parens)example(.example.com" }),
+  ];
+  await Services.logins.addLogins(loginList);
+  await reloadAndCheckLoginsGen(loginList);
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_telemetry.js b/toolkit/components/passwordmgr/test/unit/test_telemetry.js
new file mode 100644
index 0000000000..56fe6233d9
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_telemetry.js
@@ -0,0 +1,201 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests the statistics and other counters reported through telemetry.
+ */
+
+"use strict";
+
+// Globals
+
+const { TestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/TestUtils.sys.mjs"
+);
+
+const MS_PER_DAY = 24 * 60 * 60 * 1000;
+
+// To prevent intermittent failures when the test is executed at a time that is
+// very close to a day boundary, we make it deterministic by using a static
+// reference date for all the time-based statistics.
+const gReferenceTimeMs = new Date("2000-01-01T00:00:00").getTime();
+
+// Returns a milliseconds value to use with nsILoginMetaInfo properties, falling
+// approximately in the middle of the specified number of days before the
+// reference time, where zero days indicates a time within the past 24 hours.
+const daysBeforeMs = days => gReferenceTimeMs - (days + 0.5) * MS_PER_DAY;
+
+/**
+ * Contains metadata that will be attached to test logins in order to verify
+ * that the statistics collection is working properly. Most properties of the
+ * logins are initialized to the default test values already.
+ *
+ * If you update this data or any of the telemetry histograms it checks, you'll
+ * probably need to update the expected statistics in the test below.
+ */
+const StatisticsTestData = [
+  {
+    timeLastUsed: daysBeforeMs(0),
+  },
+  {
+    timeLastUsed: daysBeforeMs(1),
+  },
+  {
+    timeLastUsed: daysBeforeMs(7),
+    formActionOrigin: null,
+    httpRealm: "The HTTP Realm",
+  },
+  {
+    username: "",
+    timeLastUsed: daysBeforeMs(7),
+  },
+  {
+    username: "",
+    timeLastUsed: daysBeforeMs(30),
+  },
+  {
+    username: "",
+    timeLastUsed: daysBeforeMs(31),
+  },
+  {
+    timeLastUsed: daysBeforeMs(365),
+  },
+  {
+    username: "",
+    timeLastUsed: daysBeforeMs(366),
+  },
+  {
+    // If the login was saved in the future, it is ignored for statistiscs.
+    timeLastUsed: daysBeforeMs(-1),
+  },
+  {
+    timeLastUsed: daysBeforeMs(1000),
+  },
+];
+
+/**
+ * Triggers the collection of those statistics that are not accumulated each
+ * time an action is taken, but are a static snapshot of the current state.
+ */
+async function triggerStatisticsCollection() {
+  Services.obs.notifyObservers(null, "gather-telemetry", "" + gReferenceTimeMs);
+  await TestUtils.topicObserved("passwordmgr-gather-telemetry-complete");
+}
+
+/**
+ * Tests the telemetry histogram with the given ID contains only the specified
+ * non-zero ranges, expressed in the format { range1: value1, range2: value2 }.
+ */
+function testHistogram(histogramId, expectedNonZeroRanges) {
+  let snapshot = Services.telemetry.getHistogramById(histogramId).snapshot();
+
+  // Compute the actual ranges in the format { range1: value1, range2: value2 }.
+  let actualNonZeroRanges = {};
+  for (let [range, value] of Object.entries(snapshot.values)) {
+    if (value > 0) {
+      actualNonZeroRanges[range] = value;
+    }
+  }
+
+  // These are stringified to visualize the differences between the values.
+  info("Testing histogram: " + histogramId);
+  Assert.equal(
+    JSON.stringify(actualNonZeroRanges),
+    JSON.stringify(expectedNonZeroRanges)
+  );
+}
+
+// Tests
+
+/**
+ * Enable local telemetry recording for the duration of the tests, and prepare
+ * the test data that will be used by the following tests.
+ */
+add_setup(async () => {
+  let oldCanRecord = Services.telemetry.canRecordExtended;
+  Services.telemetry.canRecordExtended = true;
+  registerCleanupFunction(function () {
+    Services.telemetry.canRecordExtended = oldCanRecord;
+  });
+
+  let uniqueNumber = 1;
+  let logins = [];
+  for (let loginModifications of StatisticsTestData) {
+    loginModifications.origin = `http://${uniqueNumber++}.example.com`;
+    if (typeof loginModifications.httpRealm != "undefined") {
+      logins.push(TestData.authLogin(loginModifications));
+    } else {
+      logins.push(TestData.formLogin(loginModifications));
+    }
+  }
+  await Services.logins.addLogins(logins);
+});
+
+/**
+ * Tests the collection of statistics related to login metadata.
+ */
+add_task(async function test_logins_statistics() {
+  // Repeat the operation twice to test that histograms are not accumulated.
+  for (let pass of [1, 2]) {
+    info(`pass ${pass}`);
+    await triggerStatisticsCollection();
+
+    // Should record 1 in the bucket corresponding to the number of passwords.
+    testHistogram("PWMGR_NUM_SAVED_PASSWORDS", { 10: 1 });
+
+    // Should record 1 in the bucket corresponding to the number of passwords.
+    testHistogram("PWMGR_NUM_HTTPAUTH_PASSWORDS", { 1: 1 });
+
+    // For each saved login, should record 1 in the bucket corresponding to the
+    // age in days since the login was last used.
+    testHistogram("PWMGR_LOGIN_LAST_USED_DAYS", {
+      0: 1,
+      1: 1,
+      7: 2,
+      29: 2,
+      356: 2,
+      750: 1,
+    });
+
+    // Should record the number of logins without a username in bucket 0, and
+    // the number of logins with a username in bucket 1.
+    testHistogram("PWMGR_USERNAME_PRESENT", { 0: 4, 1: 6 });
+  }
+});
+
+/**
+ * Tests the collection of statistics related to hosts for which passowrd saving
+ * has been explicitly disabled.
+ */
+add_task(async function test_disabledHosts_statistics() {
+  // Should record 1 in the bucket corresponding to the number of sites for
+  // which password saving is disabled.
+  Services.logins.setLoginSavingEnabled("http://www.example.com", false);
+  await triggerStatisticsCollection();
+  testHistogram("PWMGR_BLOCKLIST_NUM_SITES", { 1: 1 });
+
+  Services.logins.setLoginSavingEnabled("http://www.example.com", true);
+  await triggerStatisticsCollection();
+  testHistogram("PWMGR_BLOCKLIST_NUM_SITES", { 0: 1 });
+});
+
+/**
+ * Tests the collection of statistics related to general settings.
+ */
+add_task(async function test_settings_statistics() {
+  let oldRememberSignons = Services.prefs.getBoolPref("signon.rememberSignons");
+  registerCleanupFunction(function () {
+    Services.prefs.setBoolPref("signon.rememberSignons", oldRememberSignons);
+  });
+
+  // Repeat the operation twice per value to test that histograms are reset.
+  for (let remember of [false, true, false, true]) {
+    // This change should be observed immediately by the login service.
+    Services.prefs.setBoolPref("signon.rememberSignons", remember);
+
+    await triggerStatisticsCollection();
+
+    // Should record 1 in either bucket 0 or bucket 1 based on the preference.
+    testHistogram("PWMGR_SAVING_ENABLED", remember ? { 1: 1 } : { 0: 1 });
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/test_vulnerable_passwords.js b/toolkit/components/passwordmgr/test/unit/test_vulnerable_passwords.js
new file mode 100644
index 0000000000..9fd5a7dfaa
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/test_vulnerable_passwords.js
@@ -0,0 +1,47 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+add_setup(async () => {
+  await Services.logins.initializationPromise;
+});
+
+add_task(async function test_vulnerable_password_methods() {
+  const storageJSON = Services.logins.wrappedJSObject._storage;
+
+  const logins = TestData.loginList();
+  Assert.greater(logins.length, 0, "Initial logins length should be > 0.");
+
+  for (const loginInfo of logins) {
+    await Services.logins.addLoginAsync(loginInfo);
+    Assert.ok(
+      !storageJSON.isPotentiallyVulnerablePassword(loginInfo),
+      "No logins should be vulnerable until addVulnerablePasswords is called."
+    );
+  }
+
+  const vulnerableLogin = logins.shift();
+  storageJSON.addPotentiallyVulnerablePassword(vulnerableLogin);
+
+  Assert.ok(
+    storageJSON.isPotentiallyVulnerablePassword(vulnerableLogin),
+    "Login should be vulnerable after calling addVulnerablePassword."
+  );
+  for (const loginInfo of logins) {
+    Assert.ok(
+      !storageJSON.isPotentiallyVulnerablePassword(loginInfo),
+      "No other logins should be vulnerable when addVulnerablePassword is called" +
+        " with a single argument"
+    );
+  }
+
+  storageJSON.clearAllPotentiallyVulnerablePasswords();
+
+  for (const loginInfo of logins) {
+    Assert.ok(
+      !storageJSON.isPotentiallyVulnerablePassword(loginInfo),
+      "No logins should be vulnerable when clearAllPotentiallyVulnerablePasswords is called."
+    );
+  }
+});
diff --git a/toolkit/components/passwordmgr/test/unit/xpcshell.toml b/toolkit/components/passwordmgr/test/unit/xpcshell.toml
new file mode 100644
index 0000000000..c048d42c2c
--- /dev/null
+++ b/toolkit/components/passwordmgr/test/unit/xpcshell.toml
@@ -0,0 +1,118 @@
+[DEFAULT]
+head = "head.js"
+skip-if = ["os == 'android'"] # Not supported on GV because we can't add/remove from storage.
+support-files = ["data/**"]
+
+["test_CSVParser.js"]
+
+["test_LoginManagerParent_doAutocompleteSearch.js"]
+skip-if = ["os == 'android'"] # Password generation not packaged/used on Android
+
+["test_LoginManagerParent_getGeneratedPassword.js"]
+skip-if = ["os == 'android'"] # Password generation not packaged/used on Android
+
+["test_LoginManagerParent_onPasswordEditedOrGenerated.js"]
+skip-if = ["os == 'android'"] # Password generation not packaged/used on Android
+
+["test_LoginManagerParent_searchAndDedupeLogins.js"]
+skip-if = ["os == 'android'"] # schemeUpgrades aren't supported
+
+["test_LoginManagerPrompter_getUsernameSuggestions.js"]
+skip-if = ["os == 'android'"] # Tests desktop's prompter
+
+["test_OSCrypto_win.js"]
+run-if = ["os == 'win'"]
+
+["test_PasswordGenerator.js"]
+skip-if = ["os == 'android'"] # Not packaged/used on Android
+
+["test_PasswordRulesManager_generatePassword.js"]
+
+["test_context_menu.js"]
+skip-if = ["os == 'android'"] # The context menu isn't used on Android.
+# LoginManagerContextMenu is only included for MOZ_BUILD_APP == 'browser'.
+run-if = ["buildapp == 'browser'"]
+
+["test_dedupeLogins.js"]
+
+["test_disabled_hosts.js"]
+
+["test_displayOrigin.js"]
+
+["test_doLoginsMatch.js"]
+
+["test_findRelatedRealms.js"]
+
+["test_getFormFields.js"]
+
+["test_getPasswordFields.js"]
+
+["test_getPasswordOrigin.js"]
+
+["test_getUserNameAndPasswordFields.js"]
+
+["test_getUsernameFieldFromUsernameOnlyForm.js"]
+
+["test_isInferredLoginForm.js"]
+
+["test_isInferredUsernameField.js"]
+
+["test_isOriginMatching.js"]
+
+["test_isProbablyANewPasswordField.js"]
+
+["test_isUsernameFieldType.js"]
+
+["test_legacy_empty_formActionOrigin.js"]
+
+["test_legacy_validation.js"]
+
+["test_login_autocomplete_result.js"]
+skip-if = ["os == 'android'"]
+
+["test_loginsBackup.js"]
+skip-if = ["os == 'android'"]
+
+# The following tests apply to any storage back-end that supports add/modify/remove.
+
+["test_logins_change.js"]
+
+["test_logins_decrypt_failure.js"]
+skip-if = ["os == 'android'"] # Bug 1171687: Needs fixing on Android
+
+["test_logins_metainfo.js"]
+
+["test_logins_search.js"]
+
+["test_maybeImportLogin.js"]
+skip-if = ["os == 'android'"] # Only used by migrator, which isn't on Android
+
+["test_module_LoginCSVImport.js"]
+
+["test_module_LoginExport.js"]
+skip-if = ["os == 'android'"] # there is no export for android
+
+["test_module_LoginManager.js"]
+
+["test_module_LoginStore.js"]
+skip-if = ["os == 'android'"]
+
+["test_notifications.js"]
+
+["test_recipes_add.js"]
+
+["test_recipes_content.js"]
+
+["test_remote_recipes.js"]
+skip-if = ["os == 'android'"]
+
+["test_search_schemeUpgrades.js"]
+
+["test_shadowHTTPLogins.js"]
+
+["test_storage.js"]
+
+["test_telemetry.js"]
+
+["test_vulnerable_passwords.js"]
+skip-if = ["os == 'android'"] # Not implemented for storage-mozStorage