Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

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

62 files changed, 18120 insertions, 0 deletions

diff --git a/comm/mail/components/preferences/actionsshared.js b/comm/mail/components/preferences/actionsshared.js
new file mode 100644
index 0000000000..aae709d957
--- /dev/null
+++ b/comm/mail/components/preferences/actionsshared.js
@@ -0,0 +1,23 @@
+/* -*- Mode: Javascript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * 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/. */
+
+var FILEACTION_SAVE_TO_DISK = 1;
+var FILEACTION_OPEN_INTERNALLY = 2;
+var FILEACTION_OPEN_DEFAULT = 3;
+var FILEACTION_OPEN_CUSTOM = 4;
+function FileAction() {}
+FileAction.prototype = {
+  type: "",
+  extension: "",
+  hasExtension: true,
+  editable: true,
+  smallIcon: "",
+  bigIcon: "",
+  typeName: "",
+  action: "",
+  mimeInfo: null,
+  customHandler: "",
+  handleMode: false,
+};
diff --git a/comm/mail/components/preferences/applicationManager.js b/comm/mail/components/preferences/applicationManager.js
new file mode 100644
index 0000000000..5ebc0f077b
--- /dev/null
+++ b/comm/mail/components/preferences/applicationManager.js
@@ -0,0 +1,112 @@
+/* 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/. */
+
+// applications.js
+/* globals gGeneralPane */
+
+var gAppManagerDialog = {
+  _removed: [],
+
+  init() {
+    this.handlerInfo = window.arguments[0];
+    var bundle = document.getElementById("appManagerBundle");
+    gGeneralPane._prefsBundle = document.getElementById("bundlePreferences");
+    var description = this.handlerInfo.typeDescription;
+    var key =
+      this.handlerInfo.wrappedHandlerInfo instanceof Ci.nsIMIMEInfo
+        ? "handleFile"
+        : "handleProtocol";
+    var contentText = bundle.getFormattedString(key, [description]);
+    contentText = bundle.getFormattedString("descriptionApplications", [
+      contentText,
+    ]);
+    document.getElementById("appDescription").textContent = contentText;
+
+    let list = document.getElementById("appList");
+    let listFragment = document.createDocumentFragment();
+    for (let app of this.handlerInfo.possibleApplicationHandlers.enumerate()) {
+      if (!gGeneralPane.isValidHandlerApp(app)) {
+        continue;
+      }
+
+      let item = document.createXULElement("richlistitem");
+      item.classList.add("typeLabel");
+      listFragment.append(item);
+      item.app = app;
+
+      let image = document.createElement("img");
+      image.classList.add("typeIcon");
+      image.setAttribute("src", gGeneralPane._getIconURLForHandlerApp(app));
+      image.setAttribute("alt", "");
+      item.appendChild(image);
+
+      let label = document.createElement("span");
+      label.classList.add("typeDescription");
+      label.textContent = app.name;
+      item.appendChild(label);
+    }
+    list.append(listFragment);
+
+    // Triggers onSelect which populates label.
+    list.selectedIndex = 0;
+  },
+
+  onOK() {
+    if (!this._removed.length) {
+      // return early to avoid calling the |store| method.
+      return;
+    }
+
+    for (var i = 0; i < this._removed.length; ++i) {
+      this.handlerInfo.removePossibleApplicationHandler(this._removed[i]);
+    }
+
+    this.handlerInfo.store();
+  },
+
+  remove() {
+    var list = document.getElementById("appList");
+    this._removed.push(list.selectedItem.app);
+    var index = list.selectedIndex;
+    list.selectedItem.remove();
+    if (list.getRowCount() == 0) {
+      // The list is now empty, make the bottom part disappear
+      document.getElementById("appDetails").hidden = true;
+    } else {
+      // Select the item at the same index, if we removed the last
+      // item of the list, select the previous item
+      if (index == list.getRowCount()) {
+        --index;
+      }
+      list.selectedIndex = index;
+    }
+  },
+
+  onSelect() {
+    var list = document.getElementById("appList");
+    if (!list.selectedItem) {
+      document.getElementById("remove").disabled = true;
+      return;
+    }
+    document.getElementById("remove").disabled = false;
+    var app = list.selectedItem.app;
+    var address = "";
+    if (app instanceof Ci.nsILocalHandlerApp) {
+      address = app.executable.path;
+    } else if (app instanceof Ci.nsIWebHandlerApp) {
+      address = app.uriTemplate;
+    } else if (app instanceof Ci.nsIWebContentHandlerInfo) {
+      address = app.uri;
+    }
+    document.getElementById("appLocation").value = address;
+    var bundle = document.getElementById("appManagerBundle");
+    var appType =
+      app instanceof Ci.nsILocalHandlerApp
+        ? "descriptionLocalApp"
+        : "descriptionWebApp";
+    document.getElementById("appType").value = bundle.getString(appType);
+  },
+};
+
+document.addEventListener("dialogaccept", () => gAppManagerDialog.onOK());
diff --git a/comm/mail/components/preferences/applicationManager.xhtml b/comm/mail/components/preferences/applicationManager.xhtml
new file mode 100644
index 0000000000..10c9346c0f
--- /dev/null
+++ b/comm/mail/components/preferences/applicationManager.xhtml
@@ -0,0 +1,76 @@
+<?xml version="1.0"?>
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+<?xml-stylesheet href="chrome://messenger/skin/input-fields.css"?>
+<?xml-stylesheet href="chrome://messenger/skin/preferences/applications.css"?>
+
+<!DOCTYPE window>
+
+<window
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  onload="gAppManagerDialog.init();"
+  data-l10n-id="app-manager-window-dialog2"
+  style="min-width: 30em"
+>
+  <dialog id="appManager" buttons="accept,cancel">
+    <script src="chrome://global/content/preferencesBindings.js" />
+    <script src="chrome://messenger/content/preferences/general.js" />
+    <script src="chrome://messenger/content/preferences/applicationManager.js" />
+
+    <commandset id="appManagerCommandSet">
+      <command
+        id="cmd_delete"
+        oncommand="gAppManagerDialog.remove();"
+        disabled="true"
+      />
+    </commandset>
+
+    <keyset id="appManagerKeyset">
+      <key id="delete" keycode="VK_DELETE" command="cmd_delete" />
+    </keyset>
+
+    <stringbundle
+      id="appManagerBundle"
+      src="chrome://messenger/locale/preferences/applicationManager.properties"
+    />
+    <stringbundle
+      id="bundlePreferences"
+      src="chrome://messenger/locale/preferences/preferences.properties"
+    />
+
+    <linkset>
+      <html:link
+        rel="localization"
+        href="messenger/preferences/application-manager.ftl"
+      />
+    </linkset>
+
+    <description id="appDescription" />
+    <separator class="thin" />
+    <hbox flex="1">
+      <richlistbox
+        id="appList"
+        onselect="gAppManagerDialog.onSelect();"
+        flex="1"
+        style="min-height: 150px"
+      />
+      <vbox>
+        <button
+          id="remove"
+          data-l10n-id="remove-app-button"
+          command="cmd_delete"
+        />
+        <spacer flex="1" />
+      </vbox>
+    </hbox>
+    <vbox id="appDetails">
+      <separator class="thin" />
+      <label id="appType" />
+      <html:input id="appLocation" type="text" readonly="readonly" />
+    </vbox>
+  </dialog>
+</window>
diff --git a/comm/mail/components/preferences/attachmentReminder.js b/comm/mail/components/preferences/attachmentReminder.js
new file mode 100644
index 0000000000..da01364b4e
--- /dev/null
+++ b/comm/mail/components/preferences/attachmentReminder.js
@@ -0,0 +1,100 @@
+/* -*- Mode: Javascript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * 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/. */
+
+var gAttachmentReminderOptionsDialog = {
+  keywordListBox: null,
+
+  init() {
+    this.keywordListBox = document.getElementById("keywordList");
+    this.buildKeywordList();
+  },
+
+  buildKeywordList() {
+    var keywordsInCsv = Services.prefs.getComplexValue(
+      "mail.compose.attachment_reminder_keywords",
+      Ci.nsIPrefLocalizedString
+    );
+    if (!keywordsInCsv) {
+      return;
+    }
+    keywordsInCsv = keywordsInCsv.data;
+    var keywordsInArr = keywordsInCsv.split(",");
+    for (let i = 0; i < keywordsInArr.length; i++) {
+      if (keywordsInArr[i]) {
+        this.keywordListBox.appendItem(keywordsInArr[i], keywordsInArr[i]);
+      }
+    }
+    if (keywordsInArr.length) {
+      this.keywordListBox.selectedIndex = 0;
+    }
+  },
+
+  async addKeyword() {
+    var input = { value: "" }; // Default to empty.
+
+    let [title, message] = await document.l10n.formatValues([
+      { id: "new-keyword-title" },
+      { id: "new-keyword-label" },
+    ]);
+
+    var ok = Services.prompt.prompt(window, title, message, input, null, {
+      value: 0,
+    });
+    if (ok && input.value) {
+      let newKey = this.keywordListBox.appendItem(input.value, input.value);
+      this.keywordListBox.ensureElementIsVisible(newKey);
+      this.keywordListBox.selectItem(newKey);
+    }
+  },
+
+  async editKeyword() {
+    if (this.keywordListBox.selectedIndex < 0) {
+      return;
+    }
+    var keywordToEdit = this.keywordListBox.selectedItem;
+    var input = { value: keywordToEdit.getAttribute("value") };
+
+    let [title, message] = await document.l10n.formatValues([
+      { id: "edit-keyword-title" },
+      { id: "edit-keyword-label" },
+    ]);
+
+    var ok = Services.prompt.prompt(window, title, message, input, null, {
+      value: 0,
+    });
+    if (ok && input.value) {
+      this.keywordListBox.selectedItem.value = input.value;
+      this.keywordListBox.selectedItem.label = input.value;
+    }
+  },
+
+  removeKeyword() {
+    if (this.keywordListBox.selectedIndex < 0) {
+      return;
+    }
+    this.keywordListBox.selectedItem.remove();
+  },
+
+  saveKeywords() {
+    var keywordList = "";
+    for (var i = 0; i < this.keywordListBox.getRowCount(); i++) {
+      keywordList += this.keywordListBox
+        .getItemAtIndex(i)
+        .getAttribute("value");
+      if (i != this.keywordListBox.getRowCount() - 1) {
+        keywordList += ",";
+      }
+    }
+
+    Services.prefs.setStringPref(
+      "mail.compose.attachment_reminder_keywords",
+      keywordList
+    );
+  },
+};
+
+document.addEventListener("dialogaccept", () =>
+  gAttachmentReminderOptionsDialog.saveKeywords()
+);
diff --git a/comm/mail/components/preferences/attachmentReminder.xhtml b/comm/mail/components/preferences/attachmentReminder.xhtml
new file mode 100644
index 0000000000..7f2f7b19ce
--- /dev/null
+++ b/comm/mail/components/preferences/attachmentReminder.xhtml
@@ -0,0 +1,54 @@
+<?xml version="1.0"?>
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+
+<!DOCTYPE window>
+
+<window
+  type="child"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  data-l10n-id="attachment-reminder-window"
+  onload="gAttachmentReminderOptionsDialog.init();"
+  style="min-width: 38em"
+>
+  <dialog id="attachmentReminderOptionsDialog" dlgbuttons="accept,cancel">
+    <script src="chrome://messenger/content/preferences/attachmentReminder.js" />
+
+    <linkset>
+      <html:link rel="localization" href="branding/brand.ftl" />
+      <html:link
+        rel="localization"
+        href="messenger/preferences/attachment-reminder.ftl"
+      />
+    </linkset>
+
+    <vbox>
+      <label control="keywordList" data-l10n-id="attachment-reminder-label" />
+      <hbox>
+        <richlistbox
+          id="keywordList"
+          flex="1"
+          ondblclick="gAttachmentReminderOptionsDialog.editKeyword();"
+        />
+        <vbox>
+          <button
+            data-l10n-id="keyword-new-button"
+            oncommand="gAttachmentReminderOptionsDialog.addKeyword();"
+          />
+          <button
+            data-l10n-id="keyword-edit-button"
+            oncommand="gAttachmentReminderOptionsDialog.editKeyword();"
+          />
+          <button
+            data-l10n-id="keyword-remove-button"
+            oncommand="gAttachmentReminderOptionsDialog.removeKeyword();"
+          />
+        </vbox>
+      </hbox>
+    </vbox>
+  </dialog>
+</window>
diff --git a/comm/mail/components/preferences/chat.inc.xhtml b/comm/mail/components/preferences/chat.inc.xhtml
new file mode 100644
index 0000000000..22b0cd3c4a
--- /dev/null
+++ b/comm/mail/components/preferences/chat.inc.xhtml
@@ -0,0 +1,198 @@
+# 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/.
+  <script src="chrome://messenger/content/preferences/chat.js"/>
+  <script src="chrome://messenger/content/preferences/messagestyle.js"/>
+
+  <stringbundle id="themesBundle"
+                src="chrome://messenger/locale/preferences/messagestyle.properties"/>
+  <html:template id="paneChat">
+    <hbox id="chatPaneCategory"
+          class="subcategory"
+          data-category="paneChat">
+      <html:h1 data-l10n-id="chat-pane-header"/>
+    </hbox>
+
+    <html:div data-category="paneChat">
+    <html:fieldset data-category="paneChat">
+      <html:legend data-l10n-id="chat-status-title"></html:legend>
+        <!-- Startup -->
+        <hbox align="center">
+          <label id="chatStartupAction"
+                 data-l10n-id="startup-label"
+                 control="messengerStartupAction"/>
+          <hbox>
+            <menulist id="messengerStartupAction" preference="messenger.startup.action">
+              <menupopup>
+                <menuitem data-l10n-id="offline-label" value="0"/>
+                <menuitem data-l10n-id="auto-connect-label" value="1"/>
+              </menupopup>
+            </menulist>
+          </hbox>
+        </hbox>
+        <separator/>
+
+        <!-- Status -->
+        <hbox align="center">
+          <checkbox id="reportIdle" data-l10n-id="idle-label"
+                    preference="messenger.status.reportIdle"/>
+          <html:input id="timeBeforeAway" type="number"
+                      class="size2 idle-reporting-enabled"
+                      min="1" max="720"
+                      preference="messenger.status.timeBeforeIdle"/>
+          <label data-l10n-id="idle-time-label" control="timeBeforeAway"/>
+        </hbox>
+        <vbox class="indent">
+          <hbox>
+            <checkbox id="autoAway"
+                      data-l10n-id="away-message-label"
+                      class="idle-reporting-enabled"
+                      preference="messenger.status.awayWhenIdle"/>
+            <spacer flex="1"/>
+          </hbox>
+          <html:input id="defaultIdleAwayMessage"
+                      type="text"
+                      class="idle-reporting-enabled indent"
+                      preference="messenger.status.defaultIdleAwayMessage"/>
+        </vbox>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="paneChat">
+    <html:fieldset data-category="paneChat">
+      <html:legend data-l10n-id="chat-notifications-title"></html:legend>
+      <hbox>
+        <checkbox id="sendTyping"
+                  data-l10n-id="send-typing-label"
+                  preference="purple.conversations.im.send_typing"/>
+        <spacer flex="1"/>
+      </hbox>
+
+      <separator/>
+
+      <hbox>
+        <label data-l10n-id="notification-label"/>
+      </hbox>
+      <hbox>
+        <checkbox id="desktopChatNotifications"
+                  data-l10n-id="show-notification-label"
+                  preference="mail.chat.show_desktop_notifications"/>
+        <hbox>
+          <menulist id="chatNotificationInfo" preference="mail.chat.notification_info">
+            <menupopup>
+              <menuitem data-l10n-id="notification-all" value="0"/>
+              <menuitem data-l10n-id="notification-name" value="1"/>
+              <menuitem data-l10n-id="notification-empty" value="2"/>
+            </menupopup>
+          </menulist>
+        </hbox>
+      </hbox>
+      <checkbox id="getAttention"
+                preference="messenger.options.getAttentionOnNewMessages"
+                data-l10n-id="notification-type-label"/>
+      <hbox align="center">
+        <checkbox id="chatNotification"
+                  data-l10n-id="chat-play-sound-label"
+                  preference="mail.chat.play_sound"/>
+        <spacer flex="1"/>
+        <button is="highlightable-button" id="playChatSound"
+                data-l10n-id="chat-play-button"
+                oncommand="gChatPane.previewSound();"/>
+      </hbox>
+      <radiogroup id="chatSoundType"
+                  class="indent"
+                  orient="vertical"
+                  preference="mail.chat.play_sound.type"
+                  aria-labelledby="chatNotification">
+        <hbox>
+          <radio id="chatSoundSystemSound"
+                 data-l10n-id="chat-system-sound-label"
+                 value="0"/>
+          <spacer flex="1"/>
+        </hbox>
+        <hbox>
+          <radio id="chatSoundCustom"
+                 data-l10n-id="chat-custom-sound-label"
+                 value="1"/>
+          <spacer flex="1"/>
+        </hbox>
+        <hbox align="center" class="input-container">
+          <html:input id="chatSoundUrlLocation"
+                      type="text"
+                      class="input-filefield indent"
+                      readonly="readonly"
+                      preference="mail.chat.play_sound.url"
+                      preference-editable="true"
+                      aria-labelledby="chatSoundCustom"/>
+          <button is="highlightable-button" id="browseForChatSound"
+                  data-l10n-id="chat-browse-sound-button"
+                  oncommand="gChatPane.browseForSoundFile();"/>
+        </hbox>
+      </radiogroup>
+    </html:fieldset>
+    </html:div>
+
+    <hbox id="chatPaneStylingCategory"
+          class="subcategory"
+          data-category="paneChat">
+      <html:h1 data-l10n-id="chat-pane-styling-header"/>
+    </hbox>
+
+    <html:div data-category="paneChat">
+    <html:fieldset data-category="paneChat">
+      <separator/>
+      <hbox align="center">
+        <label data-l10n-id="theme-label" control="messagestyle-themename"/>
+        <hbox flex="1">
+          <menulist id="messagestyle-themename"
+                    flex="1" crop="end"
+                    preference="messenger.options.messagesStyle.theme"
+                    onselect="previewObserver.currentThemeChanged();">
+            <menupopup id="theme-menupopup">
+              <menuitem id="mail-menuitem"
+                        data-l10n-id="style-mail"
+                        value="mail"/>
+              <menuitem id="bubbles-menuitem"
+                        data-l10n-id="style-bubbles"
+                        value="bubbles"/>
+              <menuitem id="dark-menuitem"
+                        data-l10n-id="style-dark"
+                        value="dark"/>
+              <menuitem id="papersheets-menuitem"
+                        data-l10n-id="style-paper"
+                        value="papersheets"/>
+              <menuitem id="simple-menuitem"
+                        data-l10n-id="style-simple"
+                        value="simple"/>
+            </menupopup>
+          </menulist>
+        </hbox>
+      </hbox>
+      <separator class="thin"/>
+      <hbox align="start">
+      <label data-l10n-id="preview-label"/>
+      <tooltip id="aHTMLTooltip" page="true"/>
+      <vbox id="previewBox" flex="1">
+        <vbox id="noPreviewScreen" flex="1" align="center" pack="center">
+          <hbox id="noPreviewBox" align="start">
+            <vbox id="noPreviewInnerBox" flex="1">
+              <label id="noPreviewTitle" data-l10n-id="no-preview-label"/>
+              <description id="noAccountDesc"
+                           data-l10n-id="no-preview-description"/>
+            </vbox>
+          </hbox>
+        </vbox>
+      </vbox>
+      </hbox>
+      <hbox align="center">
+        <label data-l10n-id="chat-variant-label" control="themevariant"/>
+        <hbox>
+          <menulist id="themevariant"
+                    preference="messenger.options.messagesStyle.variant"
+                    onselect="previewObserver.currentVariantChanged();"/>
+        </hbox>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+  </html:template>
diff --git a/comm/mail/components/preferences/chat.js b/comm/mail/components/preferences/chat.js
new file mode 100644
index 0000000000..e6e7b660c8
--- /dev/null
+++ b/comm/mail/components/preferences/chat.js
@@ -0,0 +1,193 @@
+/* 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";
+
+/* import-globals-from preferences.js */
+// messagestyle.js
+/* globals previewObserver */
+
+Preferences.addAll([
+  { id: "messenger.startup.action", type: "int" },
+  { id: "purple.conversations.im.send_typing", type: "bool" },
+  { id: "messenger.status.reportIdle", type: "bool" },
+  { id: "messenger.status.timeBeforeIdle", type: "int" },
+  { id: "messenger.status.awayWhenIdle", type: "bool" },
+  { id: "messenger.status.defaultIdleAwayMessage", type: "wstring" },
+  { id: "purple.logging.log_chats", type: "bool" },
+  { id: "purple.logging.log_ims", type: "bool" },
+  { id: "purple.logging.log_system", type: "bool" },
+  { id: "mail.chat.show_desktop_notifications", type: "bool" },
+  { id: "mail.chat.notification_info", type: "int" },
+  { id: "mail.chat.play_sound", type: "bool" },
+  { id: "mail.chat.play_sound.type", type: "int" },
+  { id: "mail.chat.play_sound.url", type: "string" },
+  { id: "messenger.options.getAttentionOnNewMessages", type: "bool" },
+  { id: "messenger.options.messagesStyle.theme", type: "string" },
+  { id: "messenger.options.messagesStyle.variant", type: "string" },
+]);
+
+var gChatPane = {
+  init() {
+    this.updateDisabledState();
+    this.updateMessageDisabledState();
+    this.updatePlaySound();
+    this.initPreview();
+
+    let element = document.getElementById("timeBeforeAway");
+    Preferences.addSyncFromPrefListener(
+      element,
+      () =>
+        Preferences.get("messenger.status.timeBeforeIdle")
+          .valueFromPreferences / 60
+    );
+    Preferences.addSyncToPrefListener(element, element => element.value * 60);
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("chatSoundUrlLocation"),
+      () => this.readSoundLocation()
+    );
+  },
+
+  initPreview() {
+    // We add this browser only when really necessary.
+    let previewBox = document.getElementById("previewBox");
+    if (previewBox.querySelector("browser")) {
+      return;
+    }
+
+    document.getElementById("noPreviewScreen").hidden = true;
+    let browser = document.createXULElement("browser", {
+      is: "conversation-browser",
+    });
+    browser.setAttribute("id", "previewbrowser");
+    browser.setAttribute("type", "content");
+    browser.setAttribute("flex", "1");
+    browser.setAttribute("tooltip", "aHTMLTooltip");
+    previewBox.appendChild(browser);
+    previewObserver.load();
+  },
+
+  updateDisabledState() {
+    let checked = Preferences.get("messenger.status.reportIdle").value;
+    document.querySelectorAll(".idle-reporting-enabled").forEach(e => {
+      e.disabled = !checked;
+    });
+  },
+
+  updateMessageDisabledState() {
+    let textbox = document.getElementById("defaultIdleAwayMessage");
+    textbox.toggleAttribute(
+      "disabled",
+      !Preferences.get("messenger.status.awayWhenIdle").value
+    );
+  },
+
+  convertURLToLocalFile(aFileURL) {
+    // convert the file url into a nsIFile
+    if (aFileURL) {
+      return Services.io
+        .getProtocolHandler("file")
+        .QueryInterface(Ci.nsIFileProtocolHandler)
+        .getFileFromURLSpec(aFileURL);
+    }
+    return null;
+  },
+
+  readSoundLocation() {
+    let chatSoundUrlLocation = document.getElementById("chatSoundUrlLocation");
+    chatSoundUrlLocation.value = Preferences.get(
+      "mail.chat.play_sound.url"
+    ).value;
+    if (chatSoundUrlLocation.value) {
+      chatSoundUrlLocation.label = this.convertURLToLocalFile(
+        chatSoundUrlLocation.value
+      ).leafName;
+      chatSoundUrlLocation.style.backgroundImage =
+        "url(moz-icon://" + chatSoundUrlLocation.label + "?size=16)";
+    }
+  },
+
+  previewSound() {
+    let sound = Cc["@mozilla.org/sound;1"].createInstance(Ci.nsISound);
+
+    let soundLocation =
+      document.getElementById("chatSoundType").value == 1
+        ? document.getElementById("chatSoundUrlLocation").value
+        : "";
+
+    // This should be in sync with the code in nsStatusBarBiffManager::PlayBiffSound.
+    if (!soundLocation.startsWith("file://")) {
+      if (Services.appinfo.OS == "Darwin") {
+        // OS X
+        sound.beep();
+      } else {
+        sound.playEventSound(Ci.nsISound.EVENT_NEW_MAIL_RECEIVED);
+      }
+    } else {
+      sound.play(Services.io.newURI(soundLocation));
+    }
+  },
+
+  browseForSoundFile() {
+    let fp = Cc["@mozilla.org/filepicker;1"].createInstance(Ci.nsIFilePicker);
+
+    // If we already have a sound file, then use the path for that sound file
+    // as the initial path in the dialog.
+    let localFile = this.convertURLToLocalFile(
+      document.getElementById("chatSoundUrlLocation").value
+    );
+    if (localFile) {
+      fp.displayDirectory = localFile.parent;
+    }
+
+    // XXX todo, persist the last sound directory and pass it in
+    fp.init(
+      window,
+      document
+        .getElementById("bundlePreferences")
+        .getString("soundFilePickerTitle"),
+      Ci.nsIFilePicker.modeOpen
+    );
+    fp.appendFilters(Ci.nsIFilePicker.filterAudio);
+    fp.appendFilters(Ci.nsIFilePicker.filterAll);
+
+    fp.open(rv => {
+      if (rv != Ci.nsIFilePicker.returnOK) {
+        return;
+      }
+
+      // convert the nsIFile into a nsIFile url
+      Preferences.get("mail.chat.play_sound.url").value = fp.fileURL.spec;
+      this.readSoundLocation(); // XXX We shouldn't have to be doing this by hand
+      this.updatePlaySound();
+    });
+  },
+
+  updatePlaySound() {
+    let soundsEnabled = Preferences.get("mail.chat.play_sound").value;
+    let soundTypeValue = Preferences.get("mail.chat.play_sound.type").value;
+    let soundUrlLocation = Preferences.get("mail.chat.play_sound.url").value;
+    let soundDisabled = !soundsEnabled || soundTypeValue != 1;
+
+    document.getElementById("chatSoundType").disabled = !soundsEnabled;
+    document.getElementById("chatSoundUrlLocation").disabled = soundDisabled;
+    document.getElementById("browseForChatSound").disabled = soundDisabled;
+    document.getElementById("playChatSound").disabled =
+      !soundsEnabled || (!soundUrlLocation && soundTypeValue != 0);
+  },
+};
+
+Preferences.get("messenger.status.reportIdle").on(
+  "change",
+  gChatPane.updateDisabledState
+);
+Preferences.get("messenger.status.awayWhenIdle").on(
+  "change",
+  gChatPane.updateMessageDisabledState
+);
+Preferences.get("mail.chat.play_sound").on("change", gChatPane.updatePlaySound);
+Preferences.get("mail.chat.play_sound.type").on(
+  "change",
+  gChatPane.updatePlaySound
+);
diff --git a/comm/mail/components/preferences/colors.js b/comm/mail/components/preferences/colors.js
new file mode 100644
index 0000000000..cd45f8ca44
--- /dev/null
+++ b/comm/mail/components/preferences/colors.js
@@ -0,0 +1,15 @@
+/* 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-globals-from ../../../../toolkit/content/preferencesBindings.js */
+
+Preferences.addAll([
+  { id: "browser.display.document_color_use", type: "int" },
+  { id: "browser.anchor_color", type: "string" },
+  { id: "browser.visited_color", type: "string" },
+  { id: "browser.underline_anchors", type: "bool" },
+  { id: "browser.display.foreground_color", type: "string" },
+  { id: "browser.display.background_color", type: "string" },
+  { id: "browser.display.use_system_colors", type: "bool" },
+]);
diff --git a/comm/mail/components/preferences/colors.xhtml b/comm/mail/components/preferences/colors.xhtml
new file mode 100644
index 0000000000..827078ba4c
--- /dev/null
+++ b/comm/mail/components/preferences/colors.xhtml
@@ -0,0 +1,90 @@
+<?xml version="1.0"?>
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+
+<!DOCTYPE window>
+
+<window type="child"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        xmlns:html="http://www.w3.org/1999/xhtml"
+        data-l10n-id="colors-dialog-window2">
+  <dialog id="ColorsDialog"
+          dlgbuttons="accept,cancel">
+
+    <linkset>
+      <html:link rel="localization" href="messenger/preferences/colors.ftl"/>
+    </linkset>
+
+    <hbox>
+      <hbox flex="1">
+      <html:div>
+      <html:fieldset>
+        <html:legend data-l10n-id="colors-dialog-legend"></html:legend>
+        <hbox align="center">
+          <label data-l10n-id="text-color-label" control="foregroundtextmenu"/>
+          <spacer flex="1"/>
+          <html:input type="color" id="foregroundtextmenu" preference="browser.display.foreground_color"/>
+        </hbox>
+        <hbox align="center" style="margin-top: 5px">
+          <label data-l10n-id="background-color-label" control="backgroundmenu"/>
+          <spacer flex="1"/>
+          <html:input type="color" id="backgroundmenu" preference="browser.display.background_color"/>
+        </hbox>
+        <separator class="thin"/>
+        <hbox align="center">
+          <checkbox id="browserUseSystemColors" data-l10n-id="use-system-colors"
+                    preference="browser.display.use_system_colors"/>
+        </hbox>
+      </html:fieldset>
+      </html:div>
+      </hbox>
+      <hbox flex="1">
+      <html:div>
+      <html:fieldset>
+        <html:legend data-l10n-id="colors-link-legend"></html:legend>
+        <hbox align="center">
+          <label data-l10n-id="link-color-label" control="unvisitedlinkmenu"/>
+          <spacer flex="1"/>
+          <html:input type="color" id="unvisitedlinkmenu" preference="browser.anchor_color"/>
+        </hbox>
+        <hbox align="center" style="margin-top: 5px">
+          <label data-l10n-id="visited-link-color-label" control="visitedlinkmenu"/>
+          <spacer flex="1"/>
+          <html:input type="color" id="visitedlinkmenu" preference="browser.visited_color"/>
+        </hbox>
+        <separator class="thin"/>
+        <hbox align="center">
+          <checkbox id="browserUnderlineAnchors" data-l10n-id="underline-link-checkbox"
+                    preference="browser.underline_anchors"/>
+        </hbox>
+      </html:fieldset>
+      </html:div>
+      </hbox>
+    </hbox>
+#ifdef XP_WIN
+    <vbox align="start">
+#else
+    <vbox>
+#endif
+      <label data-l10n-id="override-color-label"
+             control="useDocumentColors"/>
+      <menulist id="useDocumentColors"
+                preference="browser.display.document_color_use">
+        <menupopup>
+          <menuitem data-l10n-id="override-color-always"
+                    value="2" id="documentColorAlways"/>
+          <menuitem data-l10n-id="override-color-auto"
+                    value="0" id="documentColorAutomatic"/>
+          <menuitem data-l10n-id="override-color-never"
+                    value="1" id="documentColorNever"/>
+        </menupopup>
+      </menulist>
+    </vbox>
+
+    <script src="chrome://global/content/preferencesBindings.js"/>
+    <script src="chrome://messenger/content/preferences/colors.js"/>
+  </dialog>
+</window>
diff --git a/comm/mail/components/preferences/compose.inc.xhtml b/comm/mail/components/preferences/compose.inc.xhtml
new file mode 100644
index 0000000000..3ba7063084
--- /dev/null
+++ b/comm/mail/components/preferences/compose.inc.xhtml
@@ -0,0 +1,354 @@
+# 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/.
+  <script src="chrome://messenger/content/preferences/compose.js"/>
+  <script src="chrome://global/content/contentAreaUtils.js"/>
+  <script src="chrome://messenger/content/preferences/downloads.js"/>
+  <script src="chrome://communicator/content/utilityOverlay.js"/>
+
+  <stringbundle id="bundle_addressBook" src="chrome://messenger/locale/addressbook/addressBook.properties"/>
+  <html:template id="paneCompose">
+    <hbox id="compositionMainCategory"
+          class="subcategory"
+          data-category="paneCompose">
+      <html:h1 data-l10n-id="composition-category-header"/>
+    </hbox>
+
+    <html:div data-category="paneCompose">
+    <html:fieldset data-category="paneCompose">
+      <separator class="thin"/>
+      <hbox align="center">
+        <label data-l10n-id="forward-label" control="forwardMessageMode"/>
+        <hbox>
+          <menulist id="forwardMessageMode" preference="mail.forward_message_mode">
+            <menupopup>
+              <menuitem value="2" data-l10n-id="inline-label"/>
+              <menuitem value="0" data-l10n-id="as-attachment-label"/>
+            </menupopup>
+          </menulist>
+        </hbox>
+        <separator orient="vertical" class="thin"/>
+        <checkbox id="addExtension" preference="mail.forward_add_extension"
+                  data-l10n-id="extension-label"/>
+      </hbox>
+
+      <separator class="thin"/>
+
+      <hbox align="center" pack="start">
+        <checkbox id="autoSave" preference="mail.compose.autosave"
+                  data-l10n-id="auto-save-label"/>
+        <html:input id="autoSaveInterval" type="number" class="size2"
+                    min="1" max="35790"
+                    preference="mail.compose.autosaveinterval"
+                    aria-labelledby="autoSave autoSaveInterval autoSaveEnd"/>
+        <label id="autoSaveEnd" data-l10n-id="auto-save-end"/>
+      </hbox>
+      <hbox>
+        <checkbox id="mailWarnOnSendAccelKey"
+                  data-l10n-id="warn-on-send-accel-key"
+                  preference="mail.warn_on_send_accel_key"/>
+        <spacer flex="1"/>
+      </hbox>
+      <hbox>
+        <checkbox id="addLinkPreviews"
+                  data-l10n-id="add-link-previews"
+                  preference="mail.compose.add_link_preview"/>
+        <spacer flex="1"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="paneCompose">
+    <html:fieldset data-category="paneCompose">
+      <html:legend data-l10n-id="composition-spelling-title"></html:legend>
+      <hbox>
+        <checkbox id="spellCheckBeforeSend"
+                  data-l10n-id="spellcheck-label"
+                  preference="mail.SpellCheckBeforeSend"/>
+        <spacer flex="1"/>
+      </hbox>
+      <hbox>
+        <checkbox id="inlineSpellCheck"
+                  data-l10n-id="spellcheck-inline-label"
+                  preference="mail.spellcheck.inline"/>
+        <spacer flex="1"/>
+      </hbox>
+
+      <separator class="thin"/>
+
+      <vbox flex="1">
+        <label data-l10n-id="language-popup-label" control="dictionaryList"/>
+
+        <html:ul id="dictionaryList" class="indent">
+          <html:template id="dictionaryListItem">
+            <html:li>
+              <html:label>
+                <html:input type="checkbox" />
+                <html:span class="checkbox-label"></html:span>
+              </html:label>
+            </html:li>
+          </html:template>
+        </html:ul>
+
+        <label id="downloadDictionaries" class="text-link"
+               onclick="if (event.button == 0) { openDictionaryList('tab'); }"
+               data-l10n-id="download-dictionaries-link"/>
+
+        <spacer flex="1"/>
+      </vbox>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="paneCompose">
+    <html:fieldset data-category="paneCompose">
+      <html:legend data-l10n-id="compose-html-style-title"></html:legend>
+      <hbox>
+        <vbox flex="1">
+          <hbox align="center">
+            <label control="FontSelect" data-l10n-id="font-label"/>
+            <hbox flex="1">
+              <menulist id="FontSelect" preference="msgcompose.font_face"
+                        sizetopopup="pref" crop="center" flex="1">
+                <menupopup>
+                  <menuitem value="" label="&fontVarWidth.label;"/>
+                  <menuitem value="monospace" label="&fontFixedWidth.label;"/>
+                  <menuseparator/>
+                  <menuitem value="Helvetica, Arial, sans-serif" label="&fontHelvetica.label;"/>
+                  <menuitem value="Times New Roman, Times, serif" label="&fontTimes.label;"/>
+                  <menuitem value="Courier New, Courier, monospace" label="&fontCourier.label;"/>
+                  <menuseparator/>
+                </menupopup>
+              </menulist>
+            </hbox>
+
+            <label control="fontSizeSelect" data-l10n-id="font-size-label"/>
+            <hbox>
+              <menulist id="fontSizeSelect" preference="msgcompose.font_size" value="3">
+                <menupopup>
+                  <menuitem value="1" label="&size-tinyCmd.label;"/>
+                  <menuitem value="2" label="&size-smallCmd.label;"/>
+                  <menuitem value="3" label="&size-mediumCmd.label;"/>
+                  <menuitem value="4" label="&size-largeCmd.label;"/>
+                  <menuitem value="5" label="&size-extraLargeCmd.label;"/>
+                  <menuitem value="6" label="&size-hugeCmd.label;"/>
+                </menupopup>
+              </menulist>
+            </hbox>
+          </hbox>
+
+          <separator class="thin"/>
+
+          <hbox align="center">
+            <checkbox id="useReaderDefaults"
+                      data-l10n-id="default-colors-label"
+                      preference="msgcompose.default_colors"/>
+          </hbox>
+          <hbox align="center" class="indent">
+            <label id="textColorLabel"
+                   control="textColorButton"
+                   data-l10n-id="font-color-label"/>
+            <html:input type="color" id="textColorButton" preference="msgcompose.text_color"/>
+            <separator orient="vertical" class="thin"/>
+            <label id="backgroundColorLabel"
+                   control="backgroundColorButton"
+                   data-l10n-id="bg-color-label"/>
+            <html:input type="color" id="backgroundColorButton" preference="msgcompose.background_color"/>
+          </hbox>
+        </vbox>
+        <vbox>
+          <spacer flex="1"/>
+          <button is="highlightable-button"
+                  data-l10n-id="restore-html-label"
+                  oncommand="gComposePane.restoreHTMLDefaults();"/>
+        </vbox>
+      </hbox>
+
+      <separator class="thin"/>
+
+      <hbox align="center">
+        <checkbox id="defaultToParagraph"
+                  data-l10n-id="default-format-label"
+                  preference="mail.compose.default_to_paragraph"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="paneCompose">
+    <html:fieldset data-category="paneCompose">
+      <html:legend data-l10n-id="compose-send-format-title"></html:legend>
+      <radiogroup class="indent"
+                  preference="mail.default_send_format">
+        <radio value="0"
+               aria-describedby="composeSendAutomaticDescription"
+               data-l10n-id="compose-send-automatic-option" />
+        <description id="composeSendAutomaticDescription"
+                     class="indent tip-caption"
+                     data-l10n-id="compose-send-automatic-description" />
+        <radio value="3"
+               aria-describedby="composeSendBothDescription"
+               data-l10n-id="compose-send-both-option" />
+        <description id="composeSendBothDescription"
+                     class="indent tip-caption"
+                     data-l10n-id="compose-send-both-description" />
+        <radio value="2"
+               aria-describedby="composeSendHTMLDescription"
+               data-l10n-id="compose-send-html-option" />
+        <description id="composeSendHTMLDescription"
+                     class="indent tip-caption"
+                     data-l10n-id="compose-send-html-description" />
+        <radio value="1"
+               aria-describedby="composeSendPlainDescription"
+               data-l10n-id="compose-send-plain-option" />
+        <description id="composeSendPlainDescription"
+                     class="indent tip-caption"
+                     data-l10n-id="compose-send-plain-description" />
+      </radiogroup>
+    </html:fieldset>
+    </html:div>
+
+    <hbox id="compositionAddressingCategory"
+          class="subcategory"
+          data-category="paneCompose">
+      <html:h1 data-l10n-id="composition-addressing-header"/>
+    </hbox>
+
+    <html:div data-category="paneCompose">
+    <html:fieldset data-category="paneCompose">
+      <!-- Address Autocomplete -->
+      <separator class="thin"/>
+
+      <description data-l10n-id="autocomplete-description"/>
+
+      <hbox align="center">
+        <checkbox id="addressingAutocomplete" data-l10n-id="ab-label"
+                  preference="mail.enable_autocomplete"/>
+      </hbox>
+
+      <hbox align="center">
+        <checkbox id="autocompleteLDAP" data-l10n-id="directories-label"
+                  preference="ldap_2.autoComplete.useDirectory"/>
+        <hbox flex="1">
+          <menulist is="menulist-addrbooks" id="directoriesList"
+                    aria-labelledby="autocompleteLDAP"
+                    preference="ldap_2.autoComplete.directoryServer"
+                    data-l10n-id="directories-none-label"
+                    data-l10n-attrs="none"
+                    remoteonly="true"
+                    flex="1"/>
+        </hbox>
+        <button is="highlightable-button" id="editButton"
+                data-l10n-id="edit-directories-label"
+                oncommand="gComposePane.editDirectories();"
+                preference="pref.ldap.disable_button.edit_directories"/>
+      </hbox>
+
+      <separator class="thin"/>
+
+      <hbox align="center" pack="start">
+        <checkbox id="emailCollectionOutgoing" data-l10n-id="email-picker-label"
+                  preference="mail.collect_email_address_outgoing"/>
+        <hbox flex="1">
+          <menulist is="menulist-addrbooks" id="localDirectoriesList"
+                    aria-labelledby="emailCollectionOutgoing"
+                    preference="mail.collect_addressbook"
+                    localonly="true"
+                    writable="true"
+                    flex="1"/>
+        </hbox>
+      </hbox>
+
+      <hbox align="center" pack="start">
+        <label data-l10n-id="default-directory-label"
+               control="defaultStartupDirList"/>
+        <hbox flex="1">
+          <menulist is="menulist-addrbooks" id="defaultStartupDirList"
+                    oncommand="gComposePane.setDefaultStartupDir(this.value);"
+                    data-l10n-id="default-last-label"
+                    data-l10n-attrs="none"
+                    alladdressbooks="true"
+                    mailinglists="true"
+                    flex="1"/>
+        </hbox>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <hbox id="compositionAttachmentsCategory"
+          class="subcategory"
+          data-category="paneCompose">
+      <html:h1 data-l10n-id="composition-attachments-header"/>
+    </hbox>
+
+    <html:div data-category="paneCompose">
+    <html:fieldset data-category="paneCompose">
+      <hbox align="center">
+        <checkbox id="attachment_reminder_label"
+                  data-l10n-id="attachment-label"
+                  preference="mail.compose.attachment_reminder"/>
+        <spacer flex="1"/>
+        <hbox>
+          <button is="highlightable-button" id="attachment_reminder_button"
+                  data-l10n-id="attachment-options-label"
+                  oncommand="gComposePane.attachmentReminderOptionsDialog();"
+                  search-l10n-ids="
+                    attachment-reminder-window.title,
+                    attachment-reminder-label,
+                    keyword-new-button.label,
+                    keyword-edit-button.label,
+                    keyword-remove-button.label,
+                    new-keyword-title,
+                    new-keyword-label,
+                    edit-keyword-title,
+                    edit-keyword-label"/>
+        </hbox>
+      </hbox>
+      <vbox id="cloudFileBox">
+        <hbox id="cloudFileToggleAndThreshold" align="center">
+          <checkbox id="enableThreshold"
+                    data-l10n-id="enable-cloud-share"
+                    preference="mail.compose.big_attachments.notify"/>
+          <html:input id="cloudFileThreshold" type="number" min="0" class="size3"
+                      preference="mail.compose.big_attachments.threshold_kb"/>
+          <label control="cloudFileThreshold" data-l10n-id="cloud-share-size"/>
+        </hbox>
+        <hbox style="height: 480px; flex: 1 auto;">
+          <vbox id="provider-listing">
+            <richlistbox id="cloudFileView" orient="vertical"
+                         seltype="single"
+                         onoverflow="gCloudFile.onListOverflow();"
+                         onselect="gCloudFile.onSelectionChanged(event);">
+            </richlistbox>
+            <vbox id="addCloudFileAccountButtons">
+            </vbox>
+            <hbox>
+              <menulist id="addCloudFileAccount"
+                        hidden="true"
+                        data-l10n-id="add-cloud-account"
+                        data-l10n-attrs="defaultlabel"
+                        oncommand="gCloudFile.addCloudFileAccount(this.value);">
+                <menupopup id="addCloudFileAccountListItems"/>
+              </menulist>
+            </hbox>
+            <button is="highlightable-button" id="removeCloudFileAccount"
+                    disabled="true"
+                    data-l10n-id="remove-cloud-account"
+                    oncommand="gCloudFile.removeCloudFileAccount();"/>
+            <label is="text-link"
+                   id="moreProvidersLink"
+                   href="https://addons.thunderbird.net/thunderbird/tag/filelink"
+                   data-l10n-id="find-cloud-providers"/>
+          </vbox>
+          <separator class="thin" orient="vertical"/>
+          <vbox flex="1">
+            <vbox id="cloudFileDefaultPanel" flex="1">
+              <description data-l10n-id="cloud-account-description"/>
+            </vbox>
+            <vbox id="cloudFileSettingsWrapper" flex="1">
+            </vbox>
+          </vbox>
+        </hbox>
+      </vbox>
+    </html:fieldset>
+    </html:div>
+
+  </html:template>
diff --git a/comm/mail/components/preferences/compose.js b/comm/mail/components/preferences/compose.js
new file mode 100644
index 0000000000..7d9acf0622
--- /dev/null
+++ b/comm/mail/components/preferences/compose.js
@@ -0,0 +1,776 @@
+/* -*- Mode: Javascript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * 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";
+
+/* import-globals-from preferences.js */
+
+var { InlineSpellChecker } = ChromeUtils.importESModule(
+  "resource://gre/modules/InlineSpellChecker.sys.mjs"
+);
+
+// CloudFile account tools used by gCloudFile.
+var { cloudFileAccounts } = ChromeUtils.import(
+  "resource:///modules/cloudFileAccounts.jsm"
+);
+var { E10SUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/E10SUtils.sys.mjs"
+);
+var { ExtensionParent } = ChromeUtils.importESModule(
+  "resource://gre/modules/ExtensionParent.sys.mjs"
+);
+
+Preferences.addAll([
+  { id: "mail.forward_message_mode", type: "int" },
+  { id: "mail.forward_add_extension", type: "bool" },
+  { id: "mail.SpellCheckBeforeSend", type: "bool" },
+  { id: "mail.spellcheck.inline", type: "bool" },
+  { id: "mail.warn_on_send_accel_key", type: "bool" },
+  { id: "mail.compose.autosave", type: "bool" },
+  { id: "mail.compose.autosaveinterval", type: "int" },
+  { id: "mail.enable_autocomplete", type: "bool" },
+  { id: "ldap_2.autoComplete.useDirectory", type: "bool" },
+  { id: "ldap_2.autoComplete.directoryServer", type: "string" },
+  { id: "pref.ldap.disable_button.edit_directories", type: "bool" },
+  { id: "mail.collect_email_address_outgoing", type: "bool" },
+  { id: "mail.collect_addressbook", type: "string" },
+  { id: "spellchecker.dictionary", type: "unichar" },
+  { id: "msgcompose.default_colors", type: "bool" },
+  { id: "msgcompose.font_face", type: "string" },
+  { id: "msgcompose.font_size", type: "string" },
+  { id: "msgcompose.text_color", type: "string" },
+  { id: "msgcompose.background_color", type: "string" },
+  { id: "mail.compose.attachment_reminder", type: "bool" },
+  { id: "mail.compose.default_to_paragraph", type: "bool" },
+  { id: "mail.compose.big_attachments.notify", type: "bool" },
+  { id: "mail.compose.big_attachments.threshold_kb", type: "int" },
+  { id: "mail.default_send_format", type: "int" },
+  { id: "mail.compose.add_link_preview", type: "bool" },
+]);
+
+var gComposePane = {
+  mSpellChecker: null,
+
+  init() {
+    this.enableAutocomplete();
+
+    this.initLanguages();
+
+    this.populateFonts();
+
+    this.updateAutosave();
+
+    this.updateUseReaderDefaults();
+
+    this.updateAttachmentCheck();
+
+    this.updateEmailCollection();
+
+    this.initAbDefaultStartupDir();
+
+    this.setButtonColors();
+
+    // If BigFiles is disabled, hide the "Outgoing" tab, and the tab
+    // selectors, and bail out.
+    if (!Services.prefs.getBoolPref("mail.cloud_files.enabled")) {
+      // Hide the tab selector
+      let cloudFileBox = document.getElementById("cloudFileBox");
+      cloudFileBox.hidden = true;
+      return;
+    }
+
+    gCloudFile.init();
+  },
+
+  attachmentReminderOptionsDialog() {
+    gSubDialog.open(
+      "chrome://messenger/content/preferences/attachmentReminder.xhtml",
+      { features: "resizable=no" }
+    );
+  },
+
+  updateAutosave() {
+    gComposePane.enableElement(
+      document.getElementById("autoSaveInterval"),
+      Preferences.get("mail.compose.autosave").value
+    );
+  },
+
+  updateUseReaderDefaults() {
+    let useReaderDefaultsChecked = Preferences.get(
+      "msgcompose.default_colors"
+    ).value;
+    gComposePane.enableElement(
+      document.getElementById("textColorLabel"),
+      !useReaderDefaultsChecked
+    );
+    gComposePane.enableElement(
+      document.getElementById("backgroundColorLabel"),
+      !useReaderDefaultsChecked
+    );
+    gComposePane.enableElement(
+      document.getElementById("textColorButton"),
+      !useReaderDefaultsChecked
+    );
+    gComposePane.enableElement(
+      document.getElementById("backgroundColorButton"),
+      !useReaderDefaultsChecked
+    );
+  },
+
+  updateAttachmentCheck() {
+    gComposePane.enableElement(
+      document.getElementById("attachment_reminder_button"),
+      Preferences.get("mail.compose.attachment_reminder").value
+    );
+  },
+
+  updateEmailCollection() {
+    gComposePane.enableElement(
+      document.getElementById("localDirectoriesList"),
+      Preferences.get("mail.collect_email_address_outgoing").value
+    );
+  },
+
+  enableElement(aElement, aEnable) {
+    let pref = aElement.getAttribute("preference");
+    let prefIsLocked = pref ? Preferences.get(pref).locked : false;
+    aElement.disabled = !aEnable || prefIsLocked;
+  },
+
+  enableAutocomplete() {
+    let acLDAPPref = Preferences.get("ldap_2.autoComplete.useDirectory").value;
+    gComposePane.enableElement(
+      document.getElementById("directoriesList"),
+      acLDAPPref
+    );
+    gComposePane.enableElement(
+      document.getElementById("editButton"),
+      acLDAPPref
+    );
+  },
+
+  editDirectories() {
+    gSubDialog.open(
+      "chrome://messenger/content/addressbook/pref-editdirectories.xhtml"
+    );
+  },
+
+  initAbDefaultStartupDir() {
+    if (!this.startupDirListener.inited) {
+      this.startupDirListener.load();
+    }
+
+    let dirList = document.getElementById("defaultStartupDirList");
+    if (Services.prefs.getBoolPref("mail.addr_book.view.startupURIisDefault")) {
+      // Some directory is the default.
+      let startupURI = Services.prefs.getCharPref(
+        "mail.addr_book.view.startupURI"
+      );
+      dirList.value = startupURI;
+    } else {
+      // Choose item meaning there is no default startup directory any more.
+      dirList.value = "";
+    }
+  },
+
+  setButtonColors() {
+    document.getElementById("textColorButton").value = Preferences.get(
+      "msgcompose.text_color"
+    ).value;
+    document.getElementById("backgroundColorButton").value = Preferences.get(
+      "msgcompose.background_color"
+    ).value;
+  },
+
+  setDefaultStartupDir(aDirURI) {
+    if (aDirURI) {
+      // Some AB directory was selected. Set prefs to make this directory
+      // the default view when starting up the main AB.
+      Services.prefs.setCharPref("mail.addr_book.view.startupURI", aDirURI);
+      Services.prefs.setBoolPref(
+        "mail.addr_book.view.startupURIisDefault",
+        true
+      );
+    } else {
+      // Set pref that there's no default startup view directory any more.
+      Services.prefs.setBoolPref(
+        "mail.addr_book.view.startupURIisDefault",
+        false
+      );
+    }
+  },
+
+  async initLanguages() {
+    let languageList = document.getElementById("dictionaryList");
+    this.mSpellChecker = Cc["@mozilla.org/spellchecker/engine;1"].getService(
+      Ci.mozISpellCheckingEngine
+    );
+
+    // Get the list of dictionaries from the spellchecker.
+
+    let dictList = this.mSpellChecker.getDictionaryList();
+
+    // HACK: calling sortDictionaryList may fail the first time due to
+    // synchronous loading of the .ftl files. If we load the files and wait
+    // for a known value asynchronously, no such failure will happen.
+    await new Localization([
+      "toolkit/intl/languageNames.ftl",
+      "toolkit/intl/regionNames.ftl",
+    ]).formatValue("language-name-en");
+    let sortedList = new InlineSpellChecker().sortDictionaryList(dictList);
+    let activeDictionaries = Services.prefs
+      .getCharPref("spellchecker.dictionary")
+      .split(",");
+    let template = document.getElementById("dictionaryListItem");
+    languageList.replaceChildren(
+      ...sortedList.map(({ displayName, localeCode }) => {
+        let item = template.content.cloneNode(true).firstElementChild;
+        item.querySelector(".checkbox-label").textContent = displayName;
+        let input = item.querySelector("input");
+        input.setAttribute("value", localeCode);
+        input.addEventListener("change", event => {
+          let language = event.target.value;
+          let dicts = Services.prefs
+            .getCharPref("spellchecker.dictionary")
+            .split(",")
+            .filter(Boolean);
+          if (!event.target.checked) {
+            dicts = dicts.filter(item => item != language);
+          } else {
+            dicts.push(language);
+          }
+          Services.prefs.setCharPref(
+            "spellchecker.dictionary",
+            dicts.join(",")
+          );
+        });
+        input.checked = activeDictionaries.includes(localeCode);
+        return item;
+      })
+    );
+  },
+
+  populateFonts() {
+    var fontsList = document.getElementById("FontSelect");
+    try {
+      var enumerator = Cc["@mozilla.org/gfx/fontenumerator;1"].getService(
+        Ci.nsIFontEnumerator
+      );
+      var localFonts = enumerator.EnumerateAllFonts();
+      for (let i = 0; i < localFonts.length; ++i) {
+        // Remove Linux system generic fonts that collide with CSS generic fonts.
+        if (
+          localFonts[i] != "" &&
+          localFonts[i] != "serif" &&
+          localFonts[i] != "sans-serif" &&
+          localFonts[i] != "monospace"
+        ) {
+          fontsList.appendItem(localFonts[i], localFonts[i]);
+        }
+      }
+    } catch (e) {}
+    // Choose the item after the list is completely generated.
+    var preference = Preferences.get(fontsList.getAttribute("preference"));
+    fontsList.value = preference.value;
+  },
+
+  restoreHTMLDefaults() {
+    // reset throws an exception if the pref value is already the default so
+    // work around that with some try/catch exception handling
+    try {
+      Preferences.get("msgcompose.font_face").reset();
+    } catch (ex) {}
+
+    try {
+      Preferences.get("msgcompose.font_size").reset();
+    } catch (ex) {}
+
+    try {
+      Preferences.get("msgcompose.text_color").reset();
+    } catch (ex) {}
+
+    try {
+      Preferences.get("msgcompose.background_color").reset();
+    } catch (ex) {}
+
+    try {
+      Preferences.get("msgcompose.default_colors").reset();
+    } catch (ex) {}
+
+    this.updateUseReaderDefaults();
+    this.setButtonColors();
+  },
+
+  startupDirListener: {
+    inited: false,
+    domain: "mail.addr_book.view.startupURI",
+    observe(subject, topic, prefName) {
+      if (topic != "nsPref:changed") {
+        return;
+      }
+
+      // If the default startup directory prefs have changed,
+      // reinitialize the default startup dir picker to show the new value.
+      gComposePane.initAbDefaultStartupDir();
+    },
+    load() {
+      // Observe changes of our prefs.
+      Services.prefs.addObserver(this.domain, this);
+      // Unload the pref observer when preferences window is closed.
+      window.addEventListener("unload", () => this.unload(), true);
+      this.inited = true;
+    },
+
+    unload(event) {
+      Services.prefs.removeObserver(
+        gComposePane.startupDirListener.domain,
+        gComposePane.startupDirListener
+      );
+    },
+  },
+};
+
+var gCloudFile = {
+  _initialized: false,
+  _list: null,
+  _buttonContainer: null,
+  _listContainer: null,
+  _settings: null,
+  _tabpanel: null,
+  _settingsPanelWrap: null,
+  _defaultPanel: null,
+
+  get _strings() {
+    return Services.strings.createBundle(
+      "chrome://messenger/locale/preferences/applications.properties"
+    );
+  },
+
+  init() {
+    this._list = document.getElementById("cloudFileView");
+    this._buttonContainer = document.getElementById(
+      "addCloudFileAccountButtons"
+    );
+    this._addAccountButton = document.getElementById("addCloudFileAccount");
+    this._listContainer = document.getElementById(
+      "addCloudFileAccountListItems"
+    );
+    this._removeAccountButton = document.getElementById(
+      "removeCloudFileAccount"
+    );
+    this._defaultPanel = document.getElementById("cloudFileDefaultPanel");
+    this._settingsPanelWrap = document.getElementById(
+      "cloudFileSettingsWrapper"
+    );
+
+    this.updateThreshold();
+    this.rebuildView();
+
+    window.addEventListener("unload", this, { capture: false, once: true });
+
+    this._onAccountConfigured = this._onAccountConfigured.bind(this);
+    this._onProviderRegistered = this._onProviderRegistered.bind(this);
+    this._onProviderUnregistered = this._onProviderUnregistered.bind(this);
+    cloudFileAccounts.on("accountConfigured", this._onAccountConfigured);
+    cloudFileAccounts.on("providerRegistered", this._onProviderRegistered);
+    cloudFileAccounts.on("providerUnregistered", this._onProviderUnregistered);
+
+    let element = document.getElementById("cloudFileThreshold");
+    Preferences.addSyncFromPrefListener(element, () => this.readThreshold());
+    Preferences.addSyncToPrefListener(element, () => this.writeThreshold());
+
+    this._initialized = true;
+  },
+
+  destroy() {
+    // Remove any controllers or observers here.
+    cloudFileAccounts.off("accountConfigured", this._onAccountConfigured);
+    cloudFileAccounts.off("providerRegistered", this._onProviderRegistered);
+    cloudFileAccounts.off("providerUnregistered", this._onProviderUnregistered);
+  },
+
+  _onAccountConfigured(event, account) {
+    for (let item of this._list.children) {
+      if (item.value == account.accountKey) {
+        item.querySelector(".configuredWarning").hidden = account.configured;
+      }
+    }
+  },
+
+  _onProviderRegistered(event, provider) {
+    let accounts = cloudFileAccounts.getAccountsForType(provider.type);
+    accounts.sort(this._sortDisplayNames);
+
+    // Always add newly-enabled accounts to the end of the list, this makes
+    // it clearer to users what's happening.
+    for (let account of accounts) {
+      let item = this.makeRichListItemForAccount(account);
+      this._list.appendChild(item);
+    }
+
+    this._buttonContainer.appendChild(this.makeButtonForProvider(provider));
+    this._listContainer.appendChild(this.makeListItemForProvider(provider));
+  },
+
+  _onProviderUnregistered(event, type) {
+    for (let item of [...this._list.children]) {
+      // If the provider is unregistered, getAccount returns null.
+      if (!cloudFileAccounts.getAccount(item.value)) {
+        if (item.hasAttribute("selected")) {
+          this._defaultPanel.hidden = false;
+          this._settingsPanelWrap.hidden = true;
+          if (this._settings) {
+            this._settings.remove();
+          }
+          this._removeAccountButton.disabled = true;
+        }
+        item.remove();
+      }
+    }
+
+    for (let button of this._buttonContainer.children) {
+      if (button.getAttribute("value") == type) {
+        button.remove();
+      }
+    }
+
+    for (let item of this._listContainer.children) {
+      if (item.getAttribute("value") == type) {
+        item.remove();
+      }
+    }
+
+    if (this._buttonContainer.childElementCount < 1) {
+      this._buttonContainer.hidden = false;
+      this._addAccountButton.hidden = true;
+    }
+  },
+
+  makeRichListItemForAccount(aAccount) {
+    let rli = document.createXULElement("richlistitem");
+    rli.setAttribute("align", "center");
+    rli.classList.add("cloudfileAccount", "input-container");
+    rli.setAttribute("value", aAccount.accountKey);
+
+    let icon = document.createElement("img");
+    icon.classList.add("typeIcon");
+    if (aAccount.iconURL) {
+      icon.setAttribute("src", aAccount.iconURL);
+    }
+    icon.setAttribute("alt", "");
+    rli.appendChild(icon);
+
+    let label = document.createXULElement("label");
+    label.setAttribute("crop", "end");
+    label.setAttribute("flex", "1");
+    label.setAttribute(
+      "value",
+      cloudFileAccounts.getDisplayName(aAccount.accountKey)
+    );
+    label.addEventListener("click", this, true);
+    rli.appendChild(label);
+
+    let input = document.createElement("input");
+    input.setAttribute("type", "text");
+    input.setAttribute("hidden", "hidden");
+    input.addEventListener("blur", this);
+    input.addEventListener("keypress", this);
+    rli.appendChild(input);
+
+    let warningIcon = document.createElement("img");
+    warningIcon.setAttribute("class", "configuredWarning typeIcon");
+    warningIcon.setAttribute("src", "chrome://global/skin/icons/warning.svg");
+    // "title" provides the accessible name, not "alt".
+    warningIcon.setAttribute(
+      "title",
+      this._strings.GetStringFromName("notConfiguredYet")
+    );
+    if (aAccount.configured) {
+      warningIcon.hidden = true;
+    }
+    rli.appendChild(warningIcon);
+
+    return rli;
+  },
+
+  makeButtonForProvider(provider) {
+    let button = document.createXULElement("button");
+    button.setAttribute("value", provider.type);
+    button.setAttribute(
+      "label",
+      this._strings.formatStringFromName("addProvider", [provider.displayName])
+    );
+    button.setAttribute(
+      "oncommand",
+      `gCloudFile.addCloudFileAccount("${provider.type}")`
+    );
+    button.style.listStyleImage = `url("${provider.iconURL}")`;
+    return button;
+  },
+
+  makeListItemForProvider(provider) {
+    let menuitem = document.createXULElement("menuitem");
+    menuitem.classList.add("menuitem-iconic");
+    menuitem.setAttribute("value", provider.type);
+    menuitem.setAttribute("label", provider.displayName);
+    menuitem.setAttribute("image", provider.iconURL);
+    return menuitem;
+  },
+
+  // Sort the accounts by displayName.
+  _sortDisplayNames(a, b) {
+    let aName = a.displayName.toLowerCase();
+    let bName = b.displayName.toLowerCase();
+    return aName.localeCompare(bName);
+  },
+
+  rebuildView() {
+    // Clear the list of entries.
+    while (this._list.hasChildNodes()) {
+      this._list.lastChild.remove();
+    }
+
+    let accounts = cloudFileAccounts.accounts;
+    accounts.sort(this._sortDisplayNames);
+
+    for (let account of accounts) {
+      let rli = this.makeRichListItemForAccount(account);
+      this._list.appendChild(rli);
+    }
+
+    while (this._buttonContainer.hasChildNodes()) {
+      this._buttonContainer.lastChild.remove();
+    }
+
+    let providers = cloudFileAccounts.providers;
+    providers.sort(this._sortDisplayNames);
+    for (let provider of providers) {
+      this._buttonContainer.appendChild(this.makeButtonForProvider(provider));
+      this._listContainer.appendChild(this.makeListItemForProvider(provider));
+    }
+  },
+
+  onSelectionChanged(aEvent) {
+    if (!this._initialized || aEvent.target != this._list) {
+      return;
+    }
+
+    // Get the selected item
+    let selection = this._list.selectedItem;
+    this._removeAccountButton.disabled = !selection;
+    if (!selection) {
+      this._defaultPanel.hidden = false;
+      this._settingsPanelWrap.hidden = true;
+      if (this._settings) {
+        this._settings.remove();
+      }
+      return;
+    }
+
+    this._showAccountInfo(selection.value);
+  },
+
+  _showAccountInfo(aAccountKey) {
+    let account = cloudFileAccounts.getAccount(aAccountKey);
+    this._defaultPanel.hidden = true;
+    this._settingsPanelWrap.hidden = false;
+
+    let url = account.managementURL + `?accountId=${account.accountKey}`;
+
+    let browser = document.createXULElement("browser");
+    browser.setAttribute("type", "content");
+    browser.setAttribute("remote", "true");
+    browser.setAttribute("remoteType", E10SUtils.EXTENSION_REMOTE_TYPE);
+    browser.setAttribute("forcemessagemanager", "true");
+    if (account.extension) {
+      browser.setAttribute(
+        "initialBrowsingContextGroupId",
+        account.extension.policy.browsingContextGroupId
+      );
+    }
+    browser.setAttribute("disableglobalhistory", "true");
+    browser.setAttribute("messagemanagergroup", "webext-browsers");
+    browser.setAttribute("autocompletepopup", "PopupAutoComplete");
+    browser.setAttribute("selectmenulist", "ContentSelectDropdown");
+
+    browser.setAttribute("flex", "1");
+    // Allows keeping dialog background color without hoops.
+    browser.setAttribute("transparent", "true");
+
+    // If we have a past browser, we replace it. Else append to the wrapper.
+    if (this._settings) {
+      this._settings.remove();
+    }
+
+    this._settingsPanelWrap.appendChild(browser);
+    this._settings = browser;
+
+    ExtensionParent.apiManager.emit("extension-browser-inserted", browser);
+    browser.messageManager.loadFrameScript(
+      "chrome://extensions/content/ext-browser-content.js",
+      false,
+      true
+    );
+
+    let options = account.browserStyle
+      ? { stylesheets: ExtensionParent.extensionStylesheets }
+      : {};
+    browser.messageManager.sendAsyncMessage("Extension:InitBrowser", options);
+
+    browser.fixupAndLoadURIString(url, {
+      triggeringPrincipal: Services.scriptSecurityManager.getSystemPrincipal(),
+    });
+  },
+
+  onListOverflow() {
+    if (this._buttonContainer.childElementCount > 1) {
+      this._buttonContainer.hidden = true;
+      this._addAccountButton.hidden = false;
+    }
+  },
+
+  addCloudFileAccount(aType) {
+    let account = cloudFileAccounts.createAccount(aType);
+    if (!account) {
+      return;
+    }
+
+    let rli = this.makeRichListItemForAccount(account);
+    this._list.appendChild(rli);
+    this._list.selectItem(rli);
+    this._addAccountButton.removeAttribute("image");
+    this._addAccountButton.setAttribute(
+      "label",
+      this._addAccountButton.getAttribute("defaultlabel")
+    );
+    this._removeAccountButton.disabled = false;
+  },
+
+  removeCloudFileAccount() {
+    // Get the selected account key
+    let selection = this._list.selectedItem;
+    if (!selection) {
+      return;
+    }
+
+    let accountKey = selection.value;
+    let accountName = cloudFileAccounts.getDisplayName(accountKey);
+    // Does the user really want to remove this account?
+    let confirmMessage = this._strings.formatStringFromName(
+      "dialog_removeAccount",
+      [accountName]
+    );
+
+    if (Services.prompt.confirm(null, "", confirmMessage)) {
+      this._list.clearSelection();
+      cloudFileAccounts.removeAccount(accountKey);
+      let rli = this._list.querySelector(
+        "richlistitem[value='" + accountKey + "']"
+      );
+      rli.remove();
+      this._defaultPanel.hidden = false;
+      this._settingsPanelWrap.hidden = true;
+      if (this._settings) {
+        this._settings.remove();
+      }
+    }
+  },
+
+  handleEvent(aEvent) {
+    switch (aEvent.type) {
+      case "unload":
+        this.destroy();
+        break;
+      case "click": {
+        let label = aEvent.target;
+        let item = label.parentNode;
+        let input = item.querySelector("input");
+        if (!item.selected) {
+          return;
+        }
+        label.hidden = true;
+        input.value = label.value;
+        input.removeAttribute("hidden");
+        input.focus();
+        break;
+      }
+      case "blur": {
+        let input = aEvent.target;
+        let item = input.parentNode;
+        let label = item.querySelector("label");
+        cloudFileAccounts.setDisplayName(item.value, input.value);
+        label.value = input.value;
+        label.hidden = false;
+        input.setAttribute("hidden", "hidden");
+        break;
+      }
+      case "keypress": {
+        let input = aEvent.target;
+        let item = input.parentNode;
+        let label = item.querySelector("label");
+
+        if (aEvent.key == "Enter") {
+          cloudFileAccounts.setDisplayName(item.value, input.value);
+          label.value = input.value;
+          label.hidden = false;
+          input.setAttribute("hidden", "hidden");
+          gCloudFile._list.focus();
+
+          aEvent.preventDefault();
+        } else if (aEvent.key == "Escape") {
+          input.value = label.value;
+          label.hidden = false;
+          input.setAttribute("hidden", "hidden");
+          gCloudFile._list.focus();
+
+          aEvent.preventDefault();
+        }
+      }
+    }
+  },
+
+  readThreshold() {
+    let pref = Preferences.get("mail.compose.big_attachments.threshold_kb");
+    return pref.value / 1024;
+  },
+
+  writeThreshold() {
+    let threshold = document.getElementById("cloudFileThreshold");
+    let intValue = parseInt(threshold.value, 10);
+    return isNaN(intValue) ? 0 : intValue * 1024;
+  },
+
+  updateThreshold() {
+    document.getElementById("cloudFileThreshold").disabled = !Preferences.get(
+      "mail.compose.big_attachments.notify"
+    ).value;
+  },
+};
+
+Preferences.get("mail.compose.autosave").on(
+  "change",
+  gComposePane.updateAutosave
+);
+Preferences.get("mail.compose.attachment_reminder").on(
+  "change",
+  gComposePane.updateAttachmentCheck
+);
+Preferences.get("msgcompose.default_colors").on(
+  "change",
+  gComposePane.updateUseReaderDefaults
+);
+Preferences.get("ldap_2.autoComplete.useDirectory").on(
+  "change",
+  gComposePane.enableAutocomplete
+);
+Preferences.get("mail.collect_email_address_outgoing").on(
+  "change",
+  gComposePane.updateEmailCollection
+);
+Preferences.get("mail.compose.big_attachments.notify").on(
+  "change",
+  gCloudFile.updateThreshold
+);
diff --git a/comm/mail/components/preferences/connection.js b/comm/mail/components/preferences/connection.js
new file mode 100644
index 0000000000..686c2950cf
--- /dev/null
+++ b/comm/mail/components/preferences/connection.js
@@ -0,0 +1,597 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 4 -*- */
+/* 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-globals-from ../../../../toolkit/content/preferencesBindings.js */
+/* import-globals-from ./extensionControlled.js */
+
+Preferences.addAll([
+  // Add network.proxy.autoconfig_url before network.proxy.type so they're
+  // both initialized when network.proxy.type initialization triggers a call to
+  // gConnectionsDialog.updateReloadButton().
+  { id: "network.proxy.autoconfig_url", type: "string" },
+  { id: "network.proxy.type", type: "int" },
+  { id: "network.proxy.http", type: "string" },
+  { id: "network.proxy.http_port", type: "int" },
+  { id: "network.proxy.ssl", type: "string" },
+  { id: "network.proxy.ssl_port", type: "int" },
+  { id: "network.proxy.socks", type: "string" },
+  { id: "network.proxy.socks_port", type: "int" },
+  { id: "network.proxy.socks_version", type: "int" },
+  { id: "network.proxy.socks_remote_dns", type: "bool" },
+  { id: "network.proxy.no_proxies_on", type: "string" },
+  { id: "network.proxy.share_proxy_settings", type: "bool" },
+  { id: "signon.autologin.proxy", type: "bool" },
+  { id: "pref.advanced.proxies.disable_button.reload", type: "bool" },
+  { id: "network.proxy.backup.ssl", type: "string" },
+  { id: "network.proxy.backup.ssl_port", type: "int" },
+  { id: "network.trr.mode", type: "int" },
+  { id: "network.trr.uri", type: "string" },
+  { id: "network.trr.resolvers", type: "string" },
+  { id: "network.trr.custom_uri", type: "string" },
+]);
+
+window.addEventListener(
+  "DOMContentLoaded",
+  () => {
+    Preferences.get("network.proxy.type").on(
+      "change",
+      gConnectionsDialog.proxyTypeChanged.bind(gConnectionsDialog)
+    );
+    Preferences.get("network.proxy.socks_version").on(
+      "change",
+      gConnectionsDialog.updateDNSPref.bind(gConnectionsDialog)
+    );
+
+    Preferences.get("network.trr.uri").on("change", () => {
+      gConnectionsDialog.updateDnsOverHttpsUI();
+    });
+
+    Preferences.get("network.trr.resolvers").on("change", () => {
+      gConnectionsDialog.initDnsOverHttpsUI();
+    });
+
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("networkProxyType"),
+      () => gConnectionsDialog.readProxyType()
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("networkProxyHTTP"),
+      () => gConnectionsDialog.readHTTPProxyServer()
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("networkProxyHTTP_Port"),
+      () => gConnectionsDialog.readHTTPProxyPort()
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("shareAllProxies"),
+      () => gConnectionsDialog.updateProtocolPrefs()
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("networkProxySSL"),
+      () => gConnectionsDialog.readProxyProtocolPref("ssl", false)
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("networkProxySSL_Port"),
+      () => gConnectionsDialog.readProxyProtocolPref("ssl", true)
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("networkProxySOCKS"),
+      () => gConnectionsDialog.readProxyProtocolPref("socks", false)
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("networkProxySOCKS_Port"),
+      () => gConnectionsDialog.readProxyProtocolPref("socks", true)
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("networkProxySOCKSVersion"),
+      () => gConnectionsDialog.updateDNSPref()
+    );
+
+    // XXX: We can't init the DNS-over-HTTPs UI until the syncfrompref for network.trr.mode
+    //      has been called. The uiReady promise will be resolved after the first call to
+    //      readDnsOverHttpsMode and the subsequent call to initDnsOverHttpsUI has happened.
+    gConnectionsDialog.uiReady = new Promise(resolve => {
+      gConnectionsDialog._areTrrPrefsReady = false;
+      gConnectionsDialog._handleTrrPrefsReady = resolve;
+    }).then(() => {
+      gConnectionsDialog.initDnsOverHttpsUI();
+    });
+
+    let element = document.getElementById("networkDnsOverHttps");
+    Preferences.addSyncFromPrefListener(element, () =>
+      gConnectionsDialog.readDnsOverHttpsMode()
+    );
+    Preferences.addSyncToPrefListener(element, () =>
+      gConnectionsDialog.writeDnsOverHttpsMode()
+    );
+    document.documentElement.addEventListener("beforeaccept", e =>
+      gConnectionsDialog.beforeAccept(e)
+    );
+
+    document
+      .getElementById("proxyExtensionDisable")
+      .addEventListener("click", disableControllingProxyExtension);
+    gConnectionsDialog.updateProxySettingsUI();
+    initializeProxyUI(gConnectionsDialog);
+  },
+  { once: true, capture: true }
+);
+
+var gConnectionsDialog = {
+  beforeAccept(event) {
+    let dnsOverHttpsResolverChoice = document.getElementById(
+      "networkDnsOverHttpsResolverChoices"
+    ).value;
+    if (dnsOverHttpsResolverChoice == "custom") {
+      let customValue = document
+        .getElementById("networkCustomDnsOverHttpsInput")
+        .value.trim();
+      if (customValue) {
+        Services.prefs.setStringPref("network.trr.uri", customValue);
+      } else {
+        Services.prefs.clearUserPref("network.trr.uri");
+      }
+    } else {
+      Services.prefs.setStringPref(
+        "network.trr.uri",
+        dnsOverHttpsResolverChoice
+      );
+    }
+
+    var proxyTypePref = Preferences.get("network.proxy.type");
+    if (proxyTypePref.value == 2) {
+      this.doAutoconfigURLFixup();
+      return;
+    }
+
+    if (proxyTypePref.value != 1) {
+      return;
+    }
+
+    var httpProxyURLPref = Preferences.get("network.proxy.http");
+    var httpProxyPortPref = Preferences.get("network.proxy.http_port");
+    var shareProxiesPref = Preferences.get(
+      "network.proxy.share_proxy_settings"
+    );
+
+    // If the port is 0 and the proxy server is specified, focus on the port and cancel submission.
+    for (let prefName of ["http", "ssl", "socks"]) {
+      let proxyPortPref = Preferences.get(
+        "network.proxy." + prefName + "_port"
+      );
+      let proxyPref = Preferences.get("network.proxy." + prefName);
+      // Only worry about ports which are currently active. If the share option is on, then ignore
+      // all ports except the HTTP and SOCKS port
+      if (
+        proxyPref.value != "" &&
+        proxyPortPref.value == 0 &&
+        (prefName == "http" || prefName == "socks" || !shareProxiesPref.value)
+      ) {
+        document
+          .getElementById("networkProxy" + prefName.toUpperCase() + "_Port")
+          .focus();
+        event.preventDefault();
+        return;
+      }
+    }
+
+    // In the case of a shared proxy preference, backup the current values and update with the HTTP value
+    if (shareProxiesPref.value) {
+      var proxyServerURLPref = Preferences.get("network.proxy.ssl");
+      var proxyPortPref = Preferences.get("network.proxy.ssl_port");
+      var backupServerURLPref = Preferences.get("network.proxy.backup.ssl");
+      var backupPortPref = Preferences.get("network.proxy.backup.ssl_port");
+      backupServerURLPref.value =
+        backupServerURLPref.value || proxyServerURLPref.value;
+      backupPortPref.value = backupPortPref.value || proxyPortPref.value;
+      proxyServerURLPref.value = httpProxyURLPref.value;
+      proxyPortPref.value = httpProxyPortPref.value;
+    }
+
+    this.sanitizeNoProxiesPref();
+  },
+
+  checkForSystemProxy() {
+    if ("@mozilla.org/system-proxy-settings;1" in Cc) {
+      document.getElementById("systemPref").removeAttribute("hidden");
+    }
+  },
+
+  proxyTypeChanged() {
+    var proxyTypePref = Preferences.get("network.proxy.type");
+
+    // Update http
+    var httpProxyURLPref = Preferences.get("network.proxy.http");
+    httpProxyURLPref.updateControlDisabledState(proxyTypePref.value != 1);
+    var httpProxyPortPref = Preferences.get("network.proxy.http_port");
+    httpProxyPortPref.updateControlDisabledState(proxyTypePref.value != 1);
+
+    // Now update the other protocols
+    this.updateProtocolPrefs();
+
+    var shareProxiesPref = Preferences.get(
+      "network.proxy.share_proxy_settings"
+    );
+    shareProxiesPref.updateControlDisabledState(proxyTypePref.value != 1);
+    var autologinProxyPref = Preferences.get("signon.autologin.proxy");
+    autologinProxyPref.updateControlDisabledState(proxyTypePref.value == 0);
+    var noProxiesPref = Preferences.get("network.proxy.no_proxies_on");
+    noProxiesPref.updateControlDisabledState(proxyTypePref.value == 0);
+
+    var autoconfigURLPref = Preferences.get("network.proxy.autoconfig_url");
+    autoconfigURLPref.updateControlDisabledState(proxyTypePref.value != 2);
+
+    this.updateReloadButton();
+
+    document.getElementById("networkProxyNoneLocalhost").hidden =
+      Services.prefs.getBoolPref(
+        "network.proxy.allow_hijacking_localhost",
+        false
+      );
+  },
+
+  updateDNSPref() {
+    var socksVersionPref = Preferences.get("network.proxy.socks_version");
+    var socksDNSPref = Preferences.get("network.proxy.socks_remote_dns");
+    var proxyTypePref = Preferences.get("network.proxy.type");
+    var isDefinitelySocks4 =
+      proxyTypePref.value == 1 && socksVersionPref.value == 4;
+    socksDNSPref.updateControlDisabledState(
+      isDefinitelySocks4 || proxyTypePref.value == 0
+    );
+    return undefined;
+  },
+
+  updateReloadButton() {
+    // Disable the "Reload PAC" button if the selected proxy type is not PAC or
+    // if the current value of the PAC textbox does not match the value stored
+    // in prefs.  Likewise, disable the reload button if PAC is not configured
+    // in prefs.
+
+    var typedURL = document.getElementById("networkProxyAutoconfigURL").value;
+    var proxyTypeCur = Preferences.get("network.proxy.type").value;
+
+    var pacURL = Services.prefs.getCharPref("network.proxy.autoconfig_url");
+    var proxyType = Services.prefs.getIntPref("network.proxy.type");
+
+    var disableReloadPref = Preferences.get(
+      "pref.advanced.proxies.disable_button.reload"
+    );
+    disableReloadPref.updateControlDisabledState(
+      proxyTypeCur != 2 || proxyType != 2 || typedURL != pacURL
+    );
+  },
+
+  readProxyType() {
+    this.proxyTypeChanged();
+    return undefined;
+  },
+
+  updateProtocolPrefs() {
+    var proxyTypePref = Preferences.get("network.proxy.type");
+    var shareProxiesPref = Preferences.get(
+      "network.proxy.share_proxy_settings"
+    );
+    var proxyPrefs = ["ssl", "socks"];
+    for (var i = 0; i < proxyPrefs.length; ++i) {
+      var proxyServerURLPref = Preferences.get(
+        "network.proxy." + proxyPrefs[i]
+      );
+      var proxyPortPref = Preferences.get(
+        "network.proxy." + proxyPrefs[i] + "_port"
+      );
+
+      // Restore previous per-proxy custom settings, if present.
+      if (proxyPrefs[i] != "socks" && !shareProxiesPref.value) {
+        var backupServerURLPref = Preferences.get(
+          "network.proxy.backup." + proxyPrefs[i]
+        );
+        var backupPortPref = Preferences.get(
+          "network.proxy.backup." + proxyPrefs[i] + "_port"
+        );
+        if (backupServerURLPref.hasUserValue) {
+          proxyServerURLPref.value = backupServerURLPref.value;
+          backupServerURLPref.reset();
+        }
+        if (backupPortPref.hasUserValue) {
+          proxyPortPref.value = backupPortPref.value;
+          backupPortPref.reset();
+        }
+      }
+
+      proxyServerURLPref.updateElements();
+      proxyPortPref.updateElements();
+      let prefIsShared = proxyPrefs[i] != "socks" && shareProxiesPref.value;
+      proxyServerURLPref.updateControlDisabledState(
+        proxyTypePref.value != 1 || prefIsShared
+      );
+      proxyPortPref.updateControlDisabledState(
+        proxyTypePref.value != 1 || prefIsShared
+      );
+    }
+    var socksVersionPref = Preferences.get("network.proxy.socks_version");
+    socksVersionPref.updateControlDisabledState(proxyTypePref.value != 1);
+    this.updateDNSPref();
+    return undefined;
+  },
+
+  readProxyProtocolPref(aProtocol, aIsPort) {
+    if (aProtocol != "socks") {
+      var shareProxiesPref = Preferences.get(
+        "network.proxy.share_proxy_settings"
+      );
+      if (shareProxiesPref.value) {
+        var pref = Preferences.get(
+          "network.proxy.http" + (aIsPort ? "_port" : "")
+        );
+        return pref.value;
+      }
+
+      var backupPref = Preferences.get(
+        "network.proxy.backup." + aProtocol + (aIsPort ? "_port" : "")
+      );
+      return backupPref.hasUserValue ? backupPref.value : undefined;
+    }
+    return undefined;
+  },
+
+  reloadPAC() {
+    Cc["@mozilla.org/network/protocol-proxy-service;1"]
+      .getService()
+      .reloadPAC();
+  },
+
+  doAutoconfigURLFixup() {
+    var autoURL = document.getElementById("networkProxyAutoconfigURL");
+    var autoURLPref = Preferences.get("network.proxy.autoconfig_url");
+    try {
+      autoURLPref.value = autoURL.value = Services.uriFixup.getFixupURIInfo(
+        autoURL.value,
+        0
+      ).preferredURI.spec;
+    } catch (ex) {}
+  },
+
+  sanitizeNoProxiesPref() {
+    var noProxiesPref = Preferences.get("network.proxy.no_proxies_on");
+    // replace substrings of ; and \n with commas if they're neither immediately
+    // preceded nor followed by a valid separator character
+    noProxiesPref.value = noProxiesPref.value.replace(
+      /([^, \n;])[;\n]+(?![,\n;])/g,
+      "$1,"
+    );
+    // replace any remaining ; and \n since some may follow commas, etc.
+    noProxiesPref.value = noProxiesPref.value.replace(/[;\n]/g, "");
+  },
+
+  readHTTPProxyServer() {
+    var shareProxiesPref = Preferences.get(
+      "network.proxy.share_proxy_settings"
+    );
+    if (shareProxiesPref.value) {
+      this.updateProtocolPrefs();
+    }
+    return undefined;
+  },
+
+  readHTTPProxyPort() {
+    var shareProxiesPref = Preferences.get(
+      "network.proxy.share_proxy_settings"
+    );
+    if (shareProxiesPref.value) {
+      this.updateProtocolPrefs();
+    }
+    return undefined;
+  },
+
+  getProxyControls() {
+    let controlGroup = document.getElementById("networkProxyType");
+    return [
+      ...controlGroup.querySelectorAll(":scope > radio"),
+      ...controlGroup.querySelectorAll("label"),
+      ...controlGroup.querySelectorAll("input"),
+      ...controlGroup.querySelectorAll("checkbox"),
+      ...document.querySelectorAll("#networkProxySOCKSVersion > radio"),
+      ...document.querySelectorAll("#ConnectionsDialogPane > checkbox"),
+    ];
+  },
+
+  // Update the UI to show/hide the extension controlled message for
+  // proxy settings.
+  async updateProxySettingsUI() {
+    let isLocked = API_PROXY_PREFS.some(pref =>
+      Services.prefs.prefIsLocked(pref)
+    );
+
+    function setInputsDisabledState(isControlled) {
+      for (let element of gConnectionsDialog.getProxyControls()) {
+        element.disabled = isControlled;
+      }
+      gConnectionsDialog.proxyTypeChanged();
+    }
+
+    if (isLocked) {
+      // An extension can't control this setting if any pref is locked.
+      hideControllingProxyExtension();
+    } else {
+      handleControllingProxyExtension().then(setInputsDisabledState);
+    }
+  },
+
+  get dnsOverHttpsResolvers() {
+    let rawValue = Preferences.get("network.trr.resolvers", "").value;
+    // if there's no default, we'll hold its position with an empty string
+    let defaultURI = Preferences.get("network.trr.uri", "").defaultValue;
+    let providers = [];
+    if (rawValue) {
+      try {
+        providers = JSON.parse(rawValue);
+      } catch (ex) {
+        console.error(
+          `Bad JSON data in pref network.trr.resolvers: ${rawValue}`
+        );
+      }
+    }
+    if (!Array.isArray(providers)) {
+      console.error(
+        `Expected a JSON array in network.trr.resolvers: ${rawValue}`
+      );
+      providers = [];
+    }
+    let defaultIndex = providers.findIndex(p => p.url == defaultURI);
+    if (defaultIndex == -1 && defaultURI) {
+      // the default value for the pref isn't included in the resolvers list
+      // so we'll make a stub for it. Without an id, we'll have to use the url as the label
+      providers.unshift({ url: defaultURI });
+    }
+    return providers;
+  },
+
+  isDnsOverHttpsLocked() {
+    return Services.prefs.prefIsLocked("network.trr.mode");
+  },
+
+  isDnsOverHttpsEnabled() {
+    // values outside 1:4 are considered falsey/disabled in this context
+    let trrPref = Preferences.get("network.trr.mode");
+    let enabled = trrPref.value > 0 && trrPref.value < 5;
+    return enabled;
+  },
+
+  readDnsOverHttpsMode() {
+    // called to update checked element property to reflect current pref value
+    let enabled = this.isDnsOverHttpsEnabled();
+    let uriPref = Preferences.get("network.trr.uri");
+    uriPref.updateControlDisabledState(!enabled || this.isDnsOverHttpsLocked());
+    // this is the first signal we get when the prefs are available, so
+    // lazy-init if appropriate
+    if (!this._areTrrPrefsReady) {
+      this._areTrrPrefsReady = true;
+      this._handleTrrPrefsReady();
+    } else {
+      this.updateDnsOverHttpsUI();
+    }
+    return enabled;
+  },
+
+  writeDnsOverHttpsMode() {
+    // called to update pref with user change
+    let trrModeCheckbox = document.getElementById("networkDnsOverHttps");
+    // we treat checked/enabled as mode 2
+    return trrModeCheckbox.checked ? 2 : 0;
+  },
+
+  updateDnsOverHttpsUI() {
+    // init and update of the UI must wait until the pref values are ready
+    if (!this._areTrrPrefsReady) {
+      return;
+    }
+    let [menu, customInput] = this.getDnsOverHttpsControls();
+    let customContainer = document.getElementById(
+      "customDnsOverHttpsContainer"
+    );
+    let customURI = Preferences.get("network.trr.custom_uri").value;
+    let currentURI = Preferences.get("network.trr.uri").value;
+    let resolvers = this.dnsOverHttpsResolvers;
+    let isCustom = menu.value == "custom";
+
+    if (this.isDnsOverHttpsEnabled()) {
+      this.toggleDnsOverHttpsUI(false);
+      if (isCustom) {
+        // if the current and custom_uri values mismatch, update the uri pref
+        if (
+          currentURI &&
+          !customURI &&
+          !resolvers.find(r => r.url == currentURI)
+        ) {
+          Services.prefs.setStringPref("network.trr.custom_uri", currentURI);
+        }
+      }
+    } else {
+      this.toggleDnsOverHttpsUI(true);
+    }
+
+    if (!menu.disabled && isCustom) {
+      customContainer.hidden = false;
+      customInput.disabled = false;
+    } else {
+      customContainer.hidden = true;
+      customInput.disabled = true;
+    }
+
+    // The height has likely changed, find our SubDialog and tell it to resize.
+    requestAnimationFrame(() => {
+      let dialogs = window.opener.gSubDialog._dialogs;
+      let dialog = dialogs.find(d => d._frame.contentDocument == document);
+      if (dialog) {
+        dialog.resizeVertically();
+      }
+    });
+  },
+
+  getDnsOverHttpsControls() {
+    return [
+      document.getElementById("networkDnsOverHttpsResolverChoices"),
+      document.getElementById("networkCustomDnsOverHttpsInput"),
+      document.getElementById("networkDnsOverHttpsResolverChoicesLabel"),
+      document.getElementById("networkCustomDnsOverHttpsInputLabel"),
+    ];
+  },
+
+  toggleDnsOverHttpsUI(disabled) {
+    for (let element of this.getDnsOverHttpsControls()) {
+      element.disabled = disabled;
+    }
+  },
+
+  initDnsOverHttpsUI() {
+    let resolvers = this.dnsOverHttpsResolvers;
+    let defaultURI = Preferences.get("network.trr.uri").defaultValue;
+    let currentURI = Preferences.get("network.trr.uri").value;
+    let menu = document.getElementById("networkDnsOverHttpsResolverChoices");
+
+    // populate the DNS-Over-HTTPs resolver list
+    menu.removeAllItems();
+    for (let resolver of resolvers) {
+      let item = menu.appendItem(undefined, resolver.url);
+      if (resolver.url == defaultURI) {
+        document.l10n.setAttributes(
+          item,
+          "connection-dns-over-https-url-item-default",
+          {
+            name: resolver.name || resolver.url,
+          }
+        );
+      } else {
+        item.label = resolver.name || resolver.url;
+      }
+    }
+    let lastItem = menu.appendItem(undefined, "custom");
+    document.l10n.setAttributes(
+      lastItem,
+      "connection-dns-over-https-url-custom"
+    );
+
+    // set initial selection in the resolver provider picker
+    let selectedIndex = currentURI
+      ? resolvers.findIndex(r => r.url == currentURI)
+      : 0;
+    if (selectedIndex == -1) {
+      // select the last "Custom" item
+      selectedIndex = menu.itemCount - 1;
+    }
+    menu.selectedIndex = selectedIndex;
+
+    if (this.isDnsOverHttpsLocked()) {
+      // disable all the options and the checkbox itself to disallow enabling them
+      this.toggleDnsOverHttpsUI(true);
+      document.getElementById("networkDnsOverHttps").disabled = true;
+    } else {
+      this.toggleDnsOverHttpsUI(false);
+      this.updateDnsOverHttpsUI();
+      document.getElementById("networkDnsOverHttps").disabled = false;
+    }
+  },
+};
diff --git a/comm/mail/components/preferences/connection.xhtml b/comm/mail/components/preferences/connection.xhtml
new file mode 100644
index 0000000000..1bbb822f66
--- /dev/null
+++ b/comm/mail/components/preferences/connection.xhtml
@@ -0,0 +1,264 @@
+<?xml version="1.0"?>
+<!-- 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/. -->
+
+<!DOCTYPE window>
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+<?xml-stylesheet href="chrome://messenger/skin/input-fields.css"?>
+
+<window
+  type="child"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  data-l10n-id="connection-dialog-window2"
+  style="min-width: 49em"
+  onload="gConnectionsDialog.checkForSystemProxy();"
+>
+  <dialog id="ConnectionsDialog" dlgbuttons="accept,cancel">
+    <linkset>
+      <html:link
+        rel="localization"
+        href="messenger/preferences/connection.ftl"
+      />
+      <html:link
+        rel="localization"
+        href="messenger/preferences/preferences.ftl"
+      />
+      <html:link rel="localization" href="branding/brand.ftl" />
+    </linkset>
+
+    <script src="chrome://messenger/content/globalOverlay.js" />
+    <script src="chrome://global/content/editMenuOverlay.js" />
+    <script src="chrome://global/content/preferencesBindings.js" />
+    <script src="chrome://messenger/content/preferences/extensionControlled.js" />
+    <script src="chrome://messenger/content/preferences/connection.js" />
+
+    <!-- Need a wrapper div within the xul:dialog, which otherwise does not give
+     - enough height for the flex display.
+     - REMOVE when we use HTML only. -->
+    <html:div>
+      <html:div id="proxyExtensionContent" hidden="hidden">
+        <html:p id="proxyExtensionDescription">
+          <html:img data-l10n-name="extension-icon" />
+        </html:p>
+        <html:button
+          id="proxyExtensionDisable"
+          data-l10n-id="disable-extension-button"
+        >
+        </html:button>
+      </html:div>
+    </html:div>
+
+    <html:div>
+      <html:fieldset>
+        <html:legend data-l10n-id="connection-proxy-legend"></html:legend>
+
+        <radiogroup id="networkProxyType" preference="network.proxy.type">
+          <radio value="0" data-l10n-id="proxy-type-no" />
+          <radio value="4" data-l10n-id="proxy-type-wpad" />
+          <radio
+            value="5"
+            data-l10n-id="proxy-type-system"
+            id="systemPref"
+            hidden="true"
+          />
+          <radio value="1" data-l10n-id="proxy-type-manual" />
+          <box id="proxy-grid" class="indent" flex="1">
+            <html:div class="proxy-grid-row">
+              <hbox pack="end">
+                <label
+                  data-l10n-id="proxy-http-label"
+                  control="networkProxyHTTP"
+                />
+              </hbox>
+              <hbox align="center" class="input-container">
+                <html:input
+                  id="networkProxyHTTP"
+                  type="text"
+                  preference="network.proxy.http"
+                />
+                <label
+                  data-l10n-id="http-port-label"
+                  control="networkProxyHTTP_Port"
+                />
+                <html:input
+                  id="networkProxyHTTP_Port"
+                  type="number"
+                  class="size5"
+                  max="65535"
+                  preference="network.proxy.http_port"
+                />
+              </hbox>
+            </html:div>
+            <html:div class="proxy-grid-row">
+              <hbox />
+              <hbox>
+                <checkbox
+                  id="shareAllProxies"
+                  data-l10n-id="proxy-http-sharing"
+                  preference="network.proxy.share_proxy_settings"
+                  class="align-no-label"
+                />
+              </hbox>
+            </html:div>
+            <html:div class="proxy-grid-row">
+              <hbox pack="end">
+                <label
+                  data-l10n-id="proxy-https-label"
+                  control="networkProxySSL"
+                />
+              </hbox>
+              <hbox align="center" class="input-container">
+                <html:input
+                  id="networkProxySSL"
+                  type="text"
+                  preference="network.proxy.ssl"
+                />
+                <label
+                  data-l10n-id="ssl-port-label"
+                  control="networkProxySSL_Port"
+                />
+                <html:input
+                  id="networkProxySSL_Port"
+                  type="number"
+                  class="size5"
+                  max="65535"
+                  preference="network.proxy.ssl_port"
+                />
+              </hbox>
+            </html:div>
+            <separator class="thin" />
+            <html:div class="proxy-grid-row">
+              <hbox pack="end">
+                <label
+                  data-l10n-id="proxy-socks-label"
+                  control="networkProxySOCKS"
+                />
+              </hbox>
+              <hbox align="center" class="input-container">
+                <html:input
+                  id="networkProxySOCKS"
+                  type="text"
+                  preference="network.proxy.socks"
+                />
+                <label
+                  data-l10n-id="socks-port-label"
+                  control="networkProxySOCKS_Port"
+                />
+                <html:input
+                  id="networkProxySOCKS_Port"
+                  type="number"
+                  class="size5"
+                  max="65535"
+                  preference="network.proxy.socks_port"
+                />
+              </hbox>
+            </html:div>
+            <html:div class="proxy-grid-row">
+              <spacer />
+              <radiogroup
+                id="networkProxySOCKSVersion"
+                orient="horizontal"
+                class="align-no-label"
+                preference="network.proxy.socks_version"
+              >
+                <radio
+                  id="networkProxySOCKSVersion4"
+                  value="4"
+                  data-l10n-id="proxy-socks4-label"
+                />
+                <radio
+                  id="networkProxySOCKSVersion5"
+                  value="5"
+                  data-l10n-id="proxy-socks5-label"
+                />
+              </radiogroup>
+            </html:div>
+          </box>
+          <radio value="2" data-l10n-id="proxy-type-auto" />
+          <hbox class="indent input-container" flex="1" align="center">
+            <html:input
+              id="networkProxyAutoconfigURL"
+              type="url"
+              preference="network.proxy.autoconfig_url"
+              oninput="gConnectionsDialog.updateReloadButton();"
+            />
+            <button
+              id="autoReload"
+              data-l10n-id="proxy-reload-label"
+              oncommand="gConnectionsDialog.reloadPAC();"
+              preference="pref.advanced.proxies.disable_button.reload"
+            />
+          </hbox>
+        </radiogroup>
+      </html:fieldset>
+    </html:div>
+    <separator class="thin" />
+    <label data-l10n-id="no-proxy-label" control="networkProxyNone" />
+    <html:textarea
+      id="networkProxyNone"
+      rows="2"
+      preference="network.proxy.no_proxies_on"
+    />
+    <label data-l10n-id="no-proxy-example" control="networkProxyNone" />
+    <label
+      id="networkProxyNoneLocalhost"
+      control="networkProxyNone"
+      data-l10n-id="connection-proxy-noproxy-localhost-desc-2"
+    />
+    <separator class="thin" />
+    <checkbox
+      id="autologinProxy"
+      data-l10n-id="proxy-password-prompt"
+      preference="signon.autologin.proxy"
+    />
+    <checkbox
+      id="networkProxySOCKSRemoteDNS"
+      preference="network.proxy.socks_remote_dns"
+      data-l10n-id="proxy-remote-dns"
+    />
+    <separator class="thin" />
+    <checkbox
+      id="networkDnsOverHttps"
+      data-l10n-id="proxy-enable-doh"
+      preference="network.trr.mode"
+    />
+    <box id="dnsOverHttps-grid" class="indent" flex="1">
+      <html:div class="dnsOverHttps-grid-row">
+        <hbox pack="end">
+          <label
+            id="networkDnsOverHttpsResolverChoicesLabel"
+            data-l10n-id="connection-dns-over-https-url-resolver"
+            control="networkDnsOverHttpsResolverChoices"
+          />
+        </hbox>
+        <menulist
+          id="networkDnsOverHttpsResolverChoices"
+          flex="1"
+          oncommand="gConnectionsDialog.updateDnsOverHttpsUI()"
+        />
+      </html:div>
+      <html:div
+        class="dnsOverHttps-grid-row"
+        id="customDnsOverHttpsContainer"
+        hidden="hidden"
+      >
+        <hbox>
+          <label
+            id="networkCustomDnsOverHttpsInputLabel"
+            data-l10n-id="connection-dns-over-https-custom-label"
+            control="networkCustomDnsOverHttpsInput"
+          />
+        </hbox>
+        <html:input
+          id="networkCustomDnsOverHttpsInput"
+          type="url"
+          style="flex: 1"
+          preference="network.trr.custom_uri"
+        />
+      </html:div>
+    </box>
+  </dialog>
+</window>
diff --git a/comm/mail/components/preferences/cookies.js b/comm/mail/components/preferences/cookies.js
new file mode 100644
index 0000000000..da06eb7e5a
--- /dev/null
+++ b/comm/mail/components/preferences/cookies.js
@@ -0,0 +1,993 @@
+/* -*- Mode: Javascript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * 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/. */
+
+var { PluralForm } = ChromeUtils.importESModule(
+  "resource://gre/modules/PluralForm.sys.mjs"
+);
+ChromeUtils.defineESModuleGetters(this, {
+  ContextualIdentityService:
+    "resource://gre/modules/ContextualIdentityService.sys.mjs",
+});
+
+var gCookiesWindow = {
+  _hosts: {},
+  _hostOrder: [],
+  _tree: null,
+  _bundle: null,
+
+  init() {
+    Services.obs.addObserver(this, "cookie-changed");
+    Services.obs.addObserver(this, "perm-changed");
+
+    this._bundle = document.getElementById("bundlePreferences");
+    this._tree = document.getElementById("cookiesList");
+
+    this._populateList(true);
+
+    document.getElementById("filter").focus();
+
+    if (!Services.prefs.getBoolPref("privacy.userContext.enabled")) {
+      document.getElementById("userContext").hidden = true;
+      document.getElementById("userContextLabel").hidden = true;
+    }
+  },
+
+  uninit() {
+    Services.obs.removeObserver(this, "cookie-changed");
+    Services.obs.removeObserver(this, "perm-changed");
+  },
+
+  _populateList(aInitialLoad) {
+    this._loadCookies();
+    this._tree.view = this._view;
+    if (aInitialLoad) {
+      this.sort("rawHost");
+    }
+    if (this._view.rowCount > 0) {
+      this._tree.view.selection.select(0);
+    }
+
+    if (aInitialLoad) {
+      if (
+        "arguments" in window &&
+        window.arguments[2] &&
+        window.arguments[2].filterString
+      ) {
+        this.setFilter(window.arguments[2].filterString);
+      }
+    } else if (document.getElementById("filter").value != "") {
+      this.filter();
+    }
+
+    this._saveState();
+  },
+
+  _cookieEquals(aCookieA, aCookieB, aStrippedHost) {
+    return (
+      aCookieA.rawHost == aStrippedHost &&
+      aCookieA.name == aCookieB.name &&
+      aCookieA.path == aCookieB.path &&
+      ChromeUtils.isOriginAttributesEqual(
+        aCookieA.originAttributes,
+        aCookieB.originAttributes
+      )
+    );
+  },
+
+  observe(aCookie, aTopic, aData) {
+    if (aTopic != "cookie-changed") {
+      return;
+    }
+
+    if (aCookie instanceof Ci.nsICookie) {
+      var strippedHost = this._makeStrippedHost(aCookie.host);
+      if (aData == "changed") {
+        this._handleCookieChanged(aCookie, strippedHost);
+      } else if (aData == "added") {
+        this._handleCookieAdded(aCookie, strippedHost);
+      }
+    } else if (aData == "cleared") {
+      this._hosts = {};
+      this._hostOrder = [];
+
+      var oldRowCount = this._view._rowCount;
+      this._view._rowCount = 0;
+      this._tree.rowCountChanged(0, -oldRowCount);
+      this._view.selection.clearSelection();
+    } else if (aData == "reload") {
+      // first, clear any existing entries
+      this.observe(aCookie, aTopic, "cleared");
+
+      // then, reload the list
+      this._populateList(false);
+    }
+
+    // We don't yet handle aData == "deleted" - it's a less common case
+    // and is rather complicated as selection tracking is difficult
+  },
+
+  _handleCookieChanged(changedCookie, strippedHost) {
+    var rowIndex = 0;
+    var cookieItem = null;
+    if (!this._view._filtered) {
+      for (var i = 0; i < this._hostOrder.length; ++i) {
+        // (var host in this._hosts) {
+        ++rowIndex;
+        var hostItem = this._hosts[this._hostOrder[i]]; // var hostItem = this._hosts[host];
+        if (this._hostOrder[i] == strippedHost) {
+          // host == strippedHost) {
+          // Host matches, look for the cookie within this Host collection
+          // and update its data
+          for (var j = 0; j < hostItem.cookies.length; ++j) {
+            ++rowIndex;
+            var currCookie = hostItem.cookies[j];
+            if (this._cookieEquals(currCookie, changedCookie, strippedHost)) {
+              currCookie.value = changedCookie.value;
+              currCookie.isSecure = changedCookie.isSecure;
+              currCookie.isDomain = changedCookie.isDomain;
+              currCookie.expires = changedCookie.expires;
+              cookieItem = currCookie;
+              break;
+            }
+          }
+        } else if (hostItem.open) {
+          rowIndex += hostItem.cookies.length;
+        }
+      }
+    } else {
+      // Just walk the filter list to find the item. It doesn't matter that
+      // we don't update the main Host collection when we do this, because
+      // when the filter is reset the Host collection is rebuilt anyway.
+      for (rowIndex = 0; rowIndex < this._view._filterSet.length; ++rowIndex) {
+        currCookie = this._view._filterSet[rowIndex];
+        if (this._cookieEquals(currCookie, changedCookie, strippedHost)) {
+          currCookie.value = changedCookie.value;
+          currCookie.isSecure = changedCookie.isSecure;
+          currCookie.isDomain = changedCookie.isDomain;
+          currCookie.expires = changedCookie.expires;
+          cookieItem = currCookie;
+          break;
+        }
+      }
+    }
+
+    // Make sure the tree display is up to date...
+    this._tree.invalidateRow(rowIndex);
+    // ... and if the cookie is selected, update the displayed metadata too
+    if (cookieItem != null && this._view.selection.currentIndex == rowIndex) {
+      this._updateCookieData(cookieItem);
+    }
+  },
+
+  _handleCookieAdded(changedCookie, strippedHost) {
+    var rowCountImpact = 0;
+    var addedHost = { value: 0 };
+    this._addCookie(strippedHost, changedCookie, addedHost);
+    if (!this._view._filtered) {
+      // The Host collection for this cookie already exists, and it's not open,
+      // so don't increment the rowCountImpact because the user is not going to
+      // see the additional rows as they're hidden.
+      if (addedHost.value || this._hosts[strippedHost].open) {
+        ++rowCountImpact;
+      }
+    } else {
+      // We're in search mode, and the cookie being added matches
+      // the search condition, so add it to the list.
+      var c = this._makeCookieObject(strippedHost, changedCookie);
+      if (this._cookieMatchesFilter(c)) {
+        this._view._filterSet.push(
+          this._makeCookieObject(strippedHost, changedCookie)
+        );
+        ++rowCountImpact;
+      }
+    }
+    // Now update the tree display at the end (we could/should re run the sort
+    // if any to get the position correct.)
+    var oldRowCount = this._rowCount;
+    this._view._rowCount += rowCountImpact;
+    this._tree.rowCountChanged(oldRowCount - 1, rowCountImpact);
+
+    document.getElementById("removeAllCookies").disabled = this._view._filtered;
+  },
+
+  _view: {
+    QueryInterface: ChromeUtils.generateQI(["nsITreeView"]),
+    _filtered: false,
+    _filterSet: [],
+    _filterValue: "",
+    _rowCount: 0,
+    _cacheValid: 0,
+    _cacheItems: [],
+    get rowCount() {
+      return this._rowCount;
+    },
+
+    _getItemAtIndex(aIndex) {
+      if (this._filtered) {
+        return this._filterSet[aIndex];
+      }
+
+      var start = 0;
+      var count = 0,
+        hostIndex = 0;
+
+      var cacheIndex = Math.min(this._cacheValid, aIndex);
+      if (cacheIndex > 0) {
+        var cacheItem = this._cacheItems[cacheIndex];
+        start = cacheItem.start;
+        count = hostIndex = cacheItem.count;
+      }
+
+      for (let i = start; i < gCookiesWindow._hostOrder.length; ++i) {
+        let currHost = gCookiesWindow._hosts[gCookiesWindow._hostOrder[i]];
+        if (!currHost) {
+          continue;
+        }
+        if (count == aIndex) {
+          return currHost;
+        }
+        hostIndex = count;
+
+        let cacheEntry = { start: i, count };
+        var cacheStart = count;
+
+        if (currHost.open) {
+          if (count < aIndex && aIndex <= count + currHost.cookies.length) {
+            // We are looking for an entry within this host's children,
+            // enumerate them looking for the index.
+            ++count;
+            for (let j = 0; j < currHost.cookies.length; ++j) {
+              if (count == aIndex) {
+                let cookie = currHost.cookies[j];
+                cookie.parentIndex = hostIndex;
+                return cookie;
+              }
+              ++count;
+            }
+          } else {
+            // A host entry was open, but we weren't looking for an index
+            // within that host entry's children, so skip forward over the
+            // entry's children. We need to add one to increment for the
+            // host value too.
+            count += currHost.cookies.length + 1;
+          }
+        } else {
+          ++count;
+        }
+
+        for (let j = cacheStart; j < count; j++) {
+          this._cacheItems[j] = cacheEntry;
+        }
+        this._cacheValid = count - 1;
+      }
+      return null;
+    },
+
+    _removeItemAtIndex(aIndex, aCount) {
+      var removeCount = aCount === undefined ? 1 : aCount;
+      if (this._filtered) {
+        // remove the cookies from the unfiltered set so that they
+        // don't reappear when the filter is changed. See bug 410863.
+        for (let i = aIndex; i < aIndex + removeCount; ++i) {
+          let item = this._filterSet[i];
+          let parent = gCookiesWindow._hosts[item.rawHost];
+          for (var j = 0; j < parent.cookies.length; ++j) {
+            if (item == parent.cookies[j]) {
+              parent.cookies.splice(j, 1);
+              break;
+            }
+          }
+        }
+        this._filterSet.splice(aIndex, removeCount);
+        return;
+      }
+
+      let item = this._getItemAtIndex(aIndex);
+      if (!item) {
+        return;
+      }
+      this._invalidateCache(aIndex - 1);
+      if (item.container) {
+        gCookiesWindow._hosts[item.rawHost] = null;
+      } else {
+        let parent = this._getItemAtIndex(item.parentIndex);
+        for (let i = 0; i < parent.cookies.length; ++i) {
+          var cookie = parent.cookies[i];
+          if (
+            item.rawHost == cookie.rawHost &&
+            item.name == cookie.name &&
+            item.path == cookie.path &&
+            ChromeUtils.isOriginAttributesEqual(
+              item.originAttributes,
+              cookie.originAttributes
+            )
+          ) {
+            parent.cookies.splice(i, removeCount);
+          }
+        }
+      }
+    },
+
+    _invalidateCache(aIndex) {
+      this._cacheValid = Math.min(this._cacheValid, aIndex);
+    },
+
+    getCellText(aIndex, aColumn) {
+      if (!this._filtered) {
+        var item = this._getItemAtIndex(aIndex);
+        if (!item) {
+          return "";
+        }
+        if (aColumn.id == "domainCol") {
+          return item.rawHost;
+        }
+        if (aColumn.id == "nameCol") {
+          return "name" in item ? item.name : "";
+        }
+      } else if (aColumn.id == "domainCol") {
+        return this._filterSet[aIndex].rawHost;
+      } else if (aColumn.id == "nameCol") {
+        return "name" in this._filterSet[aIndex]
+          ? this._filterSet[aIndex].name
+          : "";
+      }
+      return "";
+    },
+
+    _selection: null,
+    get selection() {
+      return this._selection;
+    },
+    set selection(val) {
+      this._selection = val;
+    },
+    getRowProperties(aRow) {
+      return "";
+    },
+    getCellProperties(aRow, aColumn) {
+      return "";
+    },
+    getColumnProperties(aColumn) {
+      return "";
+    },
+    isContainer(aIndex) {
+      if (!this._filtered) {
+        var item = this._getItemAtIndex(aIndex);
+        if (!item) {
+          return false;
+        }
+        return item.container;
+      }
+      return false;
+    },
+    isContainerOpen(aIndex) {
+      if (!this._filtered) {
+        var item = this._getItemAtIndex(aIndex);
+        if (!item) {
+          return false;
+        }
+        return item.open;
+      }
+      return false;
+    },
+    isContainerEmpty(aIndex) {
+      if (!this._filtered) {
+        var item = this._getItemAtIndex(aIndex);
+        if (!item) {
+          return false;
+        }
+        return item.cookies.length == 0;
+      }
+      return false;
+    },
+    isSeparator(aIndex) {
+      return false;
+    },
+    isSorted(aIndex) {
+      return false;
+    },
+    canDrop(aIndex, aOrientation) {
+      return false;
+    },
+    drop(aIndex, aOrientation) {},
+    getParentIndex(aIndex) {
+      if (!this._filtered) {
+        var item = this._getItemAtIndex(aIndex);
+        // If an item has no parent index (i.e. it is at the top level) this
+        // function MUST return -1 otherwise we will go into an infinite loop.
+        // Containers are always top level items in the cookies tree, so make
+        // sure to return the appropriate value here.
+        if (!item || item.container) {
+          return -1;
+        }
+        return item.parentIndex;
+      }
+      return -1;
+    },
+    hasNextSibling(aParentIndex, aIndex) {
+      if (!this._filtered) {
+        // |aParentIndex| appears to be bogus, but we can get the real
+        // parent index by getting the entry for |aIndex| and reading the
+        // parentIndex field.
+        // The index of the last item in this host collection is the
+        // index of the parent + the size of the host collection, and
+        // aIndex has a next sibling if it is less than this value.
+        var item = this._getItemAtIndex(aIndex);
+        if (item) {
+          if (item.container) {
+            for (var i = aIndex + 1; i < this.rowCount; ++i) {
+              var subsequent = this._getItemAtIndex(i);
+              if (subsequent.container) {
+                return true;
+              }
+            }
+            return false;
+          }
+          let parent = this._getItemAtIndex(item.parentIndex);
+          if (parent && parent.container) {
+            return aIndex < item.parentIndex + parent.cookies.length;
+          }
+        }
+      }
+      return aIndex < this.rowCount - 1;
+    },
+    hasPreviousSibling(aIndex) {
+      if (!this._filtered) {
+        var item = this._getItemAtIndex(aIndex);
+        if (!item) {
+          return false;
+        }
+        var parent = this._getItemAtIndex(item.parentIndex);
+        if (parent && parent.container) {
+          return aIndex > item.parentIndex + 1;
+        }
+      }
+      return aIndex > 0;
+    },
+    getLevel(aIndex) {
+      if (!this._filtered) {
+        var item = this._getItemAtIndex(aIndex);
+        if (!item) {
+          return 0;
+        }
+        return item.level;
+      }
+      return 0;
+    },
+    getImageSrc(aIndex, aColumn) {},
+    getProgressMode(aIndex, aColumn) {},
+    getCellValue(aIndex, aColumn) {},
+    setTree(aTree) {},
+    toggleOpenState(aIndex) {
+      if (!this._filtered) {
+        var item = this._getItemAtIndex(aIndex);
+        if (!item) {
+          return;
+        }
+        this._invalidateCache(aIndex);
+        var multiplier = item.open ? -1 : 1;
+        var delta = multiplier * item.cookies.length;
+        this._rowCount += delta;
+        item.open = !item.open;
+        gCookiesWindow._tree.rowCountChanged(aIndex + 1, delta);
+        gCookiesWindow._tree.invalidateRow(aIndex);
+      }
+    },
+    cycleHeader(aColumn) {},
+    selectionChanged() {},
+    cycleCell(aIndex, aColumn) {},
+    isEditable(aIndex, aColumn) {
+      return false;
+    },
+    setCellValue(aIndex, aColumn, aValue) {},
+    setCellText(aIndex, aColumn, aValue) {},
+  },
+
+  _makeStrippedHost(aHost) {
+    let formattedHost = aHost.startsWith(".")
+      ? aHost.substring(1, aHost.length)
+      : aHost;
+    return formattedHost.startsWith("www.")
+      ? formattedHost.substring(4, formattedHost.length)
+      : formattedHost;
+  },
+
+  _addCookie(aStrippedHost, aCookie, aHostCount) {
+    if (!(aStrippedHost in this._hosts) || !this._hosts[aStrippedHost]) {
+      this._hosts[aStrippedHost] = {
+        cookies: [],
+        rawHost: aStrippedHost,
+        level: 0,
+        open: false,
+        container: true,
+      };
+      this._hostOrder.push(aStrippedHost);
+      ++aHostCount.value;
+    }
+
+    var c = this._makeCookieObject(aStrippedHost, aCookie);
+    this._hosts[aStrippedHost].cookies.push(c);
+  },
+
+  _makeCookieObject(aStrippedHost, aCookie) {
+    let c = {
+      name: aCookie.name,
+      value: aCookie.value,
+      isDomain: aCookie.isDomain,
+      host: aCookie.host,
+      rawHost: aStrippedHost,
+      path: aCookie.path,
+      isSecure: aCookie.isSecure,
+      expires: aCookie.expires,
+      level: 1,
+      container: false,
+      originAttributes: aCookie.originAttributes,
+    };
+    return c;
+  },
+
+  _loadCookies() {
+    var hostCount = { value: 0 };
+    this._hosts = {};
+    this._hostOrder = [];
+    for (let cookie of Services.cookies.cookies) {
+      var strippedHost = this._makeStrippedHost(cookie.host);
+      this._addCookie(strippedHost, cookie, hostCount);
+    }
+    this._view._rowCount = hostCount.value;
+  },
+
+  formatExpiresString(aExpires) {
+    if (aExpires) {
+      var date = new Date(1000 * aExpires);
+      const dateTimeFormatter = new Services.intl.DateTimeFormat(undefined, {
+        dateStyle: "long",
+        timeStyle: "long",
+      });
+      return dateTimeFormatter.format(date);
+    }
+    return this._bundle.getString("expireAtEndOfSession");
+  },
+
+  _getUserContextString(aUserContextId) {
+    if (parseInt(aUserContextId, 10) == 0) {
+      return this._bundle.getString("defaultUserContextLabel");
+    }
+
+    return ContextualIdentityService.getUserContextLabel(aUserContextId);
+  },
+
+  _updateCookieData(aItem) {
+    var seln = this._view.selection;
+    var ids = [
+      "name",
+      "value",
+      "host",
+      "path",
+      "isSecure",
+      "expires",
+      "userContext",
+    ];
+    var properties;
+
+    if (aItem && !aItem.container && seln.count > 0) {
+      properties = {
+        name: aItem.name,
+        value: aItem.value,
+        host: aItem.host,
+        path: aItem.path,
+        expires: this.formatExpiresString(aItem.expires),
+        isDomain: aItem.isDomain
+          ? this._bundle.getString("domainColon")
+          : this._bundle.getString("hostColon"),
+        isSecure: aItem.isSecure
+          ? this._bundle.getString("forSecureOnly")
+          : this._bundle.getString("forAnyConnection"),
+        userContext: this._getUserContextString(
+          aItem.originAttributes.userContextId
+        ),
+      };
+      for (var i = 0; i < ids.length; ++i) {
+        document.getElementById(ids[i]).disabled = false;
+      }
+    } else {
+      var noneSelected = this._bundle.getString("noCookieSelected");
+      properties = {
+        name: noneSelected,
+        value: noneSelected,
+        host: noneSelected,
+        path: noneSelected,
+        expires: noneSelected,
+        isSecure: noneSelected,
+        userContext: noneSelected,
+      };
+      for (i = 0; i < ids.length; ++i) {
+        document.getElementById(ids[i]).disabled = true;
+      }
+    }
+    for (var property in properties) {
+      document.getElementById(property).value = properties[property];
+    }
+  },
+
+  onCookieSelected() {
+    var item;
+    var seln = this._tree.view.selection;
+    if (!this._view._filtered) {
+      item = this._view._getItemAtIndex(seln.currentIndex);
+    } else {
+      item = this._view._filterSet[seln.currentIndex];
+    }
+
+    this._updateCookieData(item);
+
+    var rangeCount = seln.getRangeCount();
+    var selectedCookieCount = 0;
+    for (var i = 0; i < rangeCount; ++i) {
+      var min = {};
+      var max = {};
+      seln.getRangeAt(i, min, max);
+      for (var j = min.value; j <= max.value; ++j) {
+        item = this._view._getItemAtIndex(j);
+        if (!item) {
+          continue;
+        }
+        if (item.container && !item.open) {
+          selectedCookieCount += item.cookies.length;
+        } else if (!item.container) {
+          ++selectedCookieCount;
+        }
+      }
+    }
+    item = this._view._getItemAtIndex(seln.currentIndex);
+    if (item && seln.count == 1 && item.container && item.open) {
+      selectedCookieCount += 2;
+    }
+
+    let buttonLabel = this._bundle.getString("removeSelectedCookies");
+    let removeSelectedCookies = document.getElementById(
+      "removeSelectedCookies"
+    );
+    removeSelectedCookies.label = PluralForm.get(
+      selectedCookieCount,
+      buttonLabel
+    ).replace("#1", selectedCookieCount);
+
+    removeSelectedCookies.disabled = !(seln.count > 0);
+    document.getElementById("removeAllCookies").disabled = this._view._filtered;
+  },
+
+  deleteCookie() {
+    // Selection Notes
+    // - Selection always moves to *NEXT* adjacent item unless item
+    //   is last child at a given level in which case it moves to *PREVIOUS*
+    //   item
+    //
+    // Selection Cases (Somewhat Complicated)
+    //
+    // 1) Single cookie selected, host has single child
+    //    v cnn.com
+    //    //// cnn.com ///////////// goksdjf@ ////
+    //    > atwola.com
+    //
+    //    Before SelectedIndex: 1   Before RowCount: 3
+    //    After  SelectedIndex: 0   After  RowCount: 1
+    //
+    // 2) Host selected, host open
+    //    v goats.com ////////////////////////////
+    //         goats.com             sldkkfjl
+    //         goat.scom             flksj133
+    //    > atwola.com
+    //
+    //    Before SelectedIndex: 0   Before RowCount: 4
+    //    After  SelectedIndex: 0   After  RowCount: 1
+    //
+    // 3) Host selected, host closed
+    //    > goats.com ////////////////////////////
+    //    > atwola.com
+    //
+    //    Before SelectedIndex: 0   Before RowCount: 2
+    //    After  SelectedIndex: 0   After  RowCount: 1
+    //
+    // 4) Single cookie selected, host has many children
+    //    v goats.com
+    //         goats.com             sldkkfjl
+    //    //// goats.com /////////// flksjl33 ////
+    //    > atwola.com
+    //
+    //    Before SelectedIndex: 2   Before RowCount: 4
+    //    After  SelectedIndex: 1   After  RowCount: 3
+    //
+    // 5) Single cookie selected, host has many children
+    //    v goats.com
+    //    //// goats.com /////////// flksjl33 ////
+    //         goats.com             sldkkfjl
+    //    > atwola.com
+    //
+    //    Before SelectedIndex: 1   Before RowCount: 4
+    //    After  SelectedIndex: 1   After  RowCount: 3
+    var seln = this._view.selection;
+    var tbo = this._tree;
+
+    if (seln.count < 1) {
+      return;
+    }
+
+    var nextSelected = 0;
+    var rowCountImpact = 0;
+    var deleteItems = [];
+    if (!this._view._filtered) {
+      var ci = seln.currentIndex;
+      nextSelected = ci;
+      var invalidateRow = -1;
+      let item = this._view._getItemAtIndex(ci);
+      if (item.container) {
+        rowCountImpact -= (item.open ? item.cookies.length : 0) + 1;
+        deleteItems = deleteItems.concat(item.cookies);
+        if (!this._view.hasNextSibling(-1, ci)) {
+          --nextSelected;
+        }
+        this._view._removeItemAtIndex(ci);
+      } else {
+        var parent = this._view._getItemAtIndex(item.parentIndex);
+        --rowCountImpact;
+        if (parent.cookies.length == 1) {
+          --rowCountImpact;
+          deleteItems.push(item);
+          if (!this._view.hasNextSibling(-1, ci)) {
+            --nextSelected;
+          }
+          if (!this._view.hasNextSibling(-1, item.parentIndex)) {
+            --nextSelected;
+          }
+          this._view._removeItemAtIndex(item.parentIndex);
+          invalidateRow = item.parentIndex;
+        } else {
+          deleteItems.push(item);
+          if (!this._view.hasNextSibling(-1, ci)) {
+            --nextSelected;
+          }
+          this._view._removeItemAtIndex(ci);
+        }
+      }
+      this._view._rowCount += rowCountImpact;
+      tbo.rowCountChanged(ci, rowCountImpact);
+      if (invalidateRow != -1) {
+        tbo.invalidateRow(invalidateRow);
+      }
+    } else {
+      var rangeCount = seln.getRangeCount();
+      for (var i = 0; i < rangeCount; ++i) {
+        var min = {};
+        var max = {};
+        seln.getRangeAt(i, min, max);
+        nextSelected = min.value;
+        for (var j = min.value; j <= max.value; ++j) {
+          deleteItems.push(this._view._getItemAtIndex(j));
+          if (!this._view.hasNextSibling(-1, max.value)) {
+            --nextSelected;
+          }
+        }
+        var delta = max.value - min.value + 1;
+        this._view._removeItemAtIndex(min.value, delta);
+        rowCountImpact = -1 * delta;
+        this._view._rowCount += rowCountImpact;
+        tbo.rowCountChanged(min.value, rowCountImpact);
+      }
+    }
+
+    for (let item of deleteItems) {
+      Services.cookies.remove(
+        item.host,
+        item.name,
+        item.path,
+        item.originAttributes
+      );
+    }
+
+    if (nextSelected < 0) {
+      seln.clearSelection();
+    } else {
+      seln.select(nextSelected);
+      this._tree.focus();
+    }
+  },
+
+  deleteAllCookies() {
+    Services.cookies.removeAll();
+    this._tree.focus();
+  },
+
+  onCookieKeyPress(aEvent) {
+    if (aEvent.keyCode == 46) {
+      this.deleteCookie();
+    }
+  },
+
+  _lastSortProperty: "",
+  _lastSortAscending: false,
+  sort(aProperty) {
+    var ascending =
+      aProperty == this._lastSortProperty ? !this._lastSortAscending : true;
+
+    function sortByHost(a, b) {
+      return a.toLowerCase().localeCompare(b.toLowerCase());
+    }
+
+    // Sort the Non-Filtered Host Collections
+    if (aProperty == "rawHost") {
+      this._hostOrder.sort(sortByHost);
+      if (!ascending) {
+        this._hostOrder.reverse();
+      }
+    }
+
+    function sortByProperty(a, b) {
+      return a[aProperty]
+        .toLowerCase()
+        .localeCompare(b[aProperty].toLowerCase());
+    }
+    for (var host in this._hosts) {
+      var cookies = this._hosts[host].cookies;
+      cookies.sort(sortByProperty);
+      if (!ascending) {
+        cookies.reverse();
+      }
+    }
+    // Sort the Filtered List, if in Filtered mode
+    if (this._view._filtered) {
+      this._view._filterSet.sort(sortByProperty);
+      if (!ascending) {
+        this._view._filterSet.reverse();
+      }
+    }
+
+    this._view._invalidateCache(0);
+    this._view.selection.clearSelection();
+    this._view.selection.select(0);
+    this._tree.invalidate();
+    this._tree.ensureRowIsVisible(0);
+
+    this._lastSortAscending = ascending;
+    this._lastSortProperty = aProperty;
+  },
+
+  clearFilter() {
+    // Revert to single-select in the tree
+    this._tree.setAttribute("seltype", "single");
+
+    // Clear the Tree Display
+    this._view._filtered = false;
+    this._view._rowCount = 0;
+    this._tree.rowCountChanged(0, -this._view._filterSet.length);
+    this._view._filterSet = [];
+
+    // Just reload the list to make sure deletions are respected
+    this._loadCookies();
+    this._tree.view = this._view;
+
+    // Restore sort order
+    var sortby = this._lastSortProperty;
+    if (sortby == "") {
+      this._lastSortAscending = false;
+      this.sort("rawHost");
+    } else {
+      this._lastSortAscending = !this._lastSortAscending;
+      this.sort(sortby);
+    }
+
+    // Restore open state
+    for (var i = 0; i < this._openIndices.length; ++i) {
+      this._view.toggleOpenState(this._openIndices[i]);
+    }
+    this._openIndices = [];
+
+    // Restore selection
+    this._view.selection.clearSelection();
+    for (i = 0; i < this._lastSelectedRanges.length; ++i) {
+      var range = this._lastSelectedRanges[i];
+      this._view.selection.rangedSelect(range.min, range.max, true);
+    }
+    this._lastSelectedRanges = [];
+
+    document.getElementById("cookiesIntro").value =
+      this._bundle.getString("cookiesAll");
+  },
+
+  _cookieMatchesFilter(aCookie) {
+    return (
+      aCookie.rawHost.includes(this._view._filterValue) ||
+      aCookie.name.includes(this._view._filterValue) ||
+      aCookie.value.includes(this._view._filterValue)
+    );
+  },
+
+  _filterCookies(aFilterValue) {
+    this._view._filterValue = aFilterValue;
+    var cookies = [];
+    for (let i = 0; i < gCookiesWindow._hostOrder.length; ++i) {
+      let currHost = gCookiesWindow._hosts[gCookiesWindow._hostOrder[i]];
+      if (!currHost) {
+        continue;
+      }
+      for (var j = 0; j < currHost.cookies.length; ++j) {
+        var cookie = currHost.cookies[j];
+        if (this._cookieMatchesFilter(cookie)) {
+          cookies.push(cookie);
+        }
+      }
+    }
+    return cookies;
+  },
+
+  _lastSelectedRanges: [],
+  _openIndices: [],
+  _saveState() {
+    // Save selection
+    var seln = this._view.selection;
+    this._lastSelectedRanges = [];
+    var rangeCount = seln.getRangeCount();
+    for (var i = 0; i < rangeCount; ++i) {
+      var min = {};
+      var max = {};
+      seln.getRangeAt(i, min, max);
+      this._lastSelectedRanges.push({ min: min.value, max: max.value });
+    }
+
+    // Save open states
+    this._openIndices = [];
+    for (i = 0; i < this._view.rowCount; ++i) {
+      var item = this._view._getItemAtIndex(i);
+      if (item && item.container && item.open) {
+        this._openIndices.push(i);
+      }
+    }
+  },
+
+  filter() {
+    var filter = document.getElementById("filter").value;
+    if (filter == "") {
+      gCookiesWindow.clearFilter();
+      return;
+    }
+    var view = gCookiesWindow._view;
+    view._filterSet = gCookiesWindow._filterCookies(filter);
+    if (!view._filtered) {
+      // Save Display Info for the Non-Filtered mode when we first
+      // enter Filtered mode.
+      gCookiesWindow._saveState();
+      view._filtered = true;
+    }
+    // Move to multi-select in the tree
+    gCookiesWindow._tree.setAttribute("seltype", "multiple");
+
+    // Clear the display
+    var oldCount = view._rowCount;
+    view._rowCount = 0;
+    gCookiesWindow._tree.rowCountChanged(0, -oldCount);
+    // Set up the filtered display
+    view._rowCount = view._filterSet.length;
+    gCookiesWindow._tree.rowCountChanged(0, view.rowCount);
+
+    // if the view is not empty then select the first item
+    if (view.rowCount > 0) {
+      view.selection.select(0);
+    }
+
+    document.getElementById("cookiesIntro").value =
+      gCookiesWindow._bundle.getString("cookiesFiltered");
+  },
+
+  setFilter(aFilterString) {
+    document.getElementById("filter").value = aFilterString;
+    this.filter();
+  },
+
+  focusFilterBox() {
+    var filter = document.getElementById("filter");
+    filter.focus();
+    filter.select();
+  },
+};
diff --git a/comm/mail/components/preferences/cookies.xhtml b/comm/mail/components/preferences/cookies.xhtml
new file mode 100644
index 0000000000..63b6ba5a64
--- /dev/null
+++ b/comm/mail/components/preferences/cookies.xhtml
@@ -0,0 +1,117 @@
+<?xml version="1.0"?>
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+<?xml-stylesheet href="chrome://messenger/skin/input-fields.css"?>
+
+<!DOCTYPE dialog>
+
+<window id="CookiesDialog"
+        class="windowDialog"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        xmlns:html="http://www.w3.org/1999/xhtml"
+        data-l10n-id="cookies-window-dialog2"
+        onload="gCookiesWindow.init();"
+        onunload="gCookiesWindow.uninit();"
+        persist="width height">
+
+  <script src="chrome://messenger/content/globalOverlay.js"/>
+  <script src="chrome://global/content/editMenuOverlay.js"/>
+  <script src="chrome://messenger/content/preferences/cookies.js"/>
+
+  <stringbundle id="bundlePreferences"
+                src="chrome://messenger/locale/preferences/preferences.properties"/>
+
+  <linkset>
+    <html:link rel="localization" href="messenger/preferences/cookies.ftl"/>
+  </linkset>
+
+  <keyset>
+    <key data-l10n-id="window-close-key" data-l10n-attrs="key"
+         modifiers="accel" oncommand="window.close();"/>
+    <key data-l10n-id="window-focus-search-key" data-l10n-attrs="key"
+         modifiers="accel" oncommand="gCookiesWindow.focusFilterBox();"/>
+    <key data-l10n-id="window-focus-search-alt-key" data-l10n-attrs="key"
+         modifiers="accel" oncommand="gCookiesWindow.focusFilterBox();"/>
+  </keyset>
+
+  <vbox flex="1" class="contentPane largeDialogContainer">
+    <hbox align="center">
+      <label data-l10n-id="filter-search-label" control="filter"/>
+      <search-textbox id="filter"
+                      flex="1"
+                      aria-controls="cookiesList"
+                      oncommand="gCookiesWindow.filter();"/>
+    </hbox>
+    <separator class="thin"/>
+    <label control="cookiesList" id="cookiesIntro" data-l10n-id="cookies-on-system-label"/>
+    <separator class="thin"/>
+    <tree id="cookiesList" flex="1" style="height: 10em;"
+          onkeypress="gCookiesWindow.onCookieKeyPress(event)"
+          onselect="gCookiesWindow.onCookieSelected();"
+          hidecolumnpicker="true" seltype="single">
+      <treecols>
+        <treecol id="domainCol" data-l10n-id="treecol-site-header"
+                 primary="true"
+                 persist="width"
+                 onclick="gCookiesWindow.sort('rawHost');"/>
+        <splitter class="tree-splitter"/>
+        <treecol id="nameCol" data-l10n-id="treecol-name-header"
+                 persist="width"
+                 onclick="gCookiesWindow.sort('name');"/>
+      </treecols>
+      <treechildren id="cookiesChildren"/>
+    </tree>
+    <hbox id="cookieInfoSettings" flex="1">
+      <vbox>
+        <vbox flex="1" pack="center" align="end">
+          <label id="nameLabel" control="name" data-l10n-id="props-name-label"/>
+        </vbox>
+        <vbox flex="1" pack="center" align="end">
+          <label id="valueLabel" control="value" data-l10n-id="props-value-label"/>
+        </vbox>
+        <vbox flex="1" pack="center" align="end">
+          <label id="isDomain" control="host" data-l10n-id="props-domain-label"/>
+        </vbox>
+        <vbox flex="1" pack="center" align="end">
+          <label id="pathLabel" control="path" data-l10n-id="props-path-label"/>
+        </vbox>
+        <vbox flex="1" pack="center" align="end">
+          <label id="isSecureLabel" control="isSecure" data-l10n-id="props-secure-label"/>
+        </vbox>
+        <vbox flex="1" pack="center" align="end">
+          <label id="expiresLabel" control="expires" data-l10n-id="props-expires-label"/>
+        </vbox>
+        <vbox id="userContextLabel" flex="1" pack="center" align="end">
+          <label control="userContext" data-l10n-id="props-container-label"/>
+        </vbox>
+      </vbox>
+      <vbox flex="1">
+        <html:input id="name" type="text" readonly="readonly"/>
+        <html:input id="value" type="text" readonly="readonly"/>
+        <html:input id="host" type="text" readonly="readonly"/>
+        <html:input id="path" type="text" readonly="readonly"/>
+        <html:input id="isSecure" type="text" readonly="readonly"/>
+        <html:input id="expires" type="text" readonly="readonly"/>
+        <html:input id="userContext" type="text" readonly="readonly"/>
+      </vbox>
+    </hbox>
+  </vbox>
+  <hbox align="end">
+    <hbox class="actionButtons" flex="1">
+      <button id="removeSelectedCookies" disabled="true"
+              data-l10n-id="remove-cookie-button"
+              oncommand="gCookiesWindow.deleteCookie();"/>
+      <button id="removeAllCookies" disabled="true"
+              data-l10n-id="remove-all-cookies-button"
+              oncommand="gCookiesWindow.deleteAllCookies();"/>
+      <spacer flex="1"/>
+#ifndef XP_MACOSX
+      <button oncommand="window.close();"
+              data-l10n-id="cookie-close-button"/>
+#endif
+    </hbox>
+  </hbox>
+</window>
diff --git a/comm/mail/components/preferences/dockoptions.js b/comm/mail/components/preferences/dockoptions.js
new file mode 100644
index 0000000000..d518150551
--- /dev/null
+++ b/comm/mail/components/preferences/dockoptions.js
@@ -0,0 +1,11 @@
+/* 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-globals-from ../../../../toolkit/content/preferencesBindings.js */
+
+Preferences.addAll([
+  { id: "mail.biff.animate_dock_icon", type: "bool" },
+  { id: "mail.biff.show_badge", type: "bool" },
+  { id: "mail.biff.use_new_count_in_badge", type: "bool" },
+]);
diff --git a/comm/mail/components/preferences/dockoptions.xhtml b/comm/mail/components/preferences/dockoptions.xhtml
new file mode 100644
index 0000000000..978cbe1e2d
--- /dev/null
+++ b/comm/mail/components/preferences/dockoptions.xhtml
@@ -0,0 +1,59 @@
+<?xml version="1.0"?>
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+
+<!DOCTYPE window>
+
+<window type="child"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        xmlns:html="http://www.w3.org/1999/xhtml"
+        data-l10n-id="dock-options-window-dialog2"
+        style="min-width: 33em;">
+  <dialog id="DockOptionsDialog"
+          dlgbuttons="accept,cancel">
+
+    <linkset>
+      <html:link rel="localization" href="messenger/preferences/dock-options.ftl"/>
+    </linkset>
+    <hbox orient="vertical">
+#ifdef XP_MACOSX
+      <checkbox id="newMailNotificationBounce"
+                data-l10n-id="bounce-system-dock-icon"
+                preference="mail.biff.animate_dock_icon"/>
+#endif
+#ifdef XP_WIN
+      <checkbox id="newMailBadge"
+                data-l10n-id="dock-options-show-badge"
+                preference="mail.biff.show_badge"/>
+#endif
+      <separator class="thin"/>
+      <html:div>
+      <html:fieldset>
+        <html:legend data-l10n-id="dock-icon-legend"></html:legend>
+        <vbox>
+        <separator class="thin"/>
+        <label data-l10n-id="dock-icon-show-label"/>
+        <radiogroup id="dockCount"
+                    preference="mail.biff.use_new_count_in_badge"
+                    class="indent" orient="vertical">
+          <radio id="dockCountAll" value="false"
+                 data-l10n-id="count-unread-messages-radio"/>
+          <radio id="dockCountNew" value="true"
+                 data-l10n-id="count-new-messages-radio"/>
+        </radiogroup>
+        </vbox>
+      </html:fieldset>
+      </html:div>
+#ifdef XP_MACOSX
+      <separator/>
+      <description class="bold" data-l10n-id="notification-settings-info2"/>
+#endif
+    </hbox>
+
+    <script src="chrome://global/content/preferencesBindings.js"/>
+    <script src="chrome://messenger/content/preferences/dockoptions.js"/>
+  </dialog>
+</window>
diff --git a/comm/mail/components/preferences/downloads.js b/comm/mail/components/preferences/downloads.js
new file mode 100644
index 0000000000..ede1543492
--- /dev/null
+++ b/comm/mail/components/preferences/downloads.js
@@ -0,0 +1,132 @@
+/* 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-globals-from preferences.js */
+
+var { Downloads } = ChromeUtils.importESModule(
+  "resource://gre/modules/Downloads.sys.mjs"
+);
+var { FileUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/FileUtils.sys.mjs"
+);
+
+Preferences.addAll([
+  { id: "browser.download.useDownloadDir", type: "bool" },
+  { id: "browser.download.folderList", type: "int" },
+  { id: "browser.download.downloadDir", type: "file" },
+  { id: "browser.download.dir", type: "file" },
+  { id: "pref.downloads.disable_button.edit_actions", type: "bool" },
+]);
+
+var gDownloadDirSection = {
+  async chooseFolder() {
+    var fp = Cc["@mozilla.org/filepicker;1"].createInstance(Ci.nsIFilePicker);
+    var bundlePreferences = document.getElementById("bundlePreferences");
+    var title = bundlePreferences.getString("chooseAttachmentsFolderTitle");
+    fp.init(window, title, Ci.nsIFilePicker.modeGetFolder);
+
+    var customDirPref = Preferences.get("browser.download.dir");
+    if (customDirPref.value) {
+      fp.displayDirectory = customDirPref.value;
+    }
+    fp.appendFilters(Ci.nsIFilePicker.filterAll);
+
+    let rv = await new Promise(resolve => fp.open(resolve));
+    if (rv != Ci.nsIFilePicker.returnOK || !fp.file) {
+      return;
+    }
+
+    let file = fp.file.QueryInterface(Ci.nsIFile);
+    let currentDirPref = Preferences.get("browser.download.downloadDir");
+    customDirPref.value = currentDirPref.value = file;
+    let folderListPref = Preferences.get("browser.download.folderList");
+    folderListPref.value = await this._fileToIndex(file);
+  },
+
+  onReadUseDownloadDir() {
+    this.readDownloadDirPref();
+    var downloadFolder = document.getElementById("downloadFolder");
+    var chooseFolder = document.getElementById("chooseFolder");
+    var preference = Preferences.get("browser.download.useDownloadDir");
+    var dirPreference = Preferences.get("browser.download.dir");
+    downloadFolder.disabled = !preference.value || dirPreference.locked;
+    chooseFolder.disabled = !preference.value || dirPreference.locked;
+    return undefined;
+  },
+
+  async _fileToIndex(aFile) {
+    if (!aFile || aFile.equals(await this._getDownloadsFolder("Desktop"))) {
+      return 0;
+    } else if (aFile.equals(await this._getDownloadsFolder("Downloads"))) {
+      return 1;
+    }
+    return 2;
+  },
+
+  async _indexToFile(aIndex) {
+    switch (aIndex) {
+      case 0:
+        return this._getDownloadsFolder("Desktop");
+      case 1:
+        return this._getDownloadsFolder("Downloads");
+    }
+    var customDirPref = Preferences.get("browser.download.dir");
+    return customDirPref.value;
+  },
+
+  async _getDownloadsFolder(aFolder) {
+    switch (aFolder) {
+      case "Desktop":
+        return Services.dirsvc.get("Desk", Ci.nsIFile);
+      case "Downloads":
+        let downloadsDir = await Downloads.getSystemDownloadsDirectory();
+        return new FileUtils.File(downloadsDir);
+    }
+    throw new Error(
+      "ASSERTION FAILED: folder type should be 'Desktop' or 'Downloads'"
+    );
+  },
+
+  async readDownloadDirPref() {
+    var folderListPref = Preferences.get("browser.download.folderList");
+    var bundlePreferences = document.getElementById("bundlePreferences");
+    var downloadFolder = document.getElementById("downloadFolder");
+
+    var customDirPref = Preferences.get("browser.download.dir");
+    var customIndex = customDirPref.value
+      ? await this._fileToIndex(customDirPref.value)
+      : 0;
+    if (customIndex == 0) {
+      downloadFolder.value = bundlePreferences.getString("desktopFolderName");
+    } else if (customIndex == 1) {
+      downloadFolder.value = bundlePreferences.getString(
+        "myDownloadsFolderName"
+      );
+    } else {
+      downloadFolder.value = customDirPref.value
+        ? customDirPref.value.path
+        : "";
+    }
+
+    var currentDirPref = Preferences.get("browser.download.downloadDir");
+    var downloadDir =
+      currentDirPref.value || (await this._indexToFile(folderListPref.value));
+    if (downloadDir) {
+      let urlSpec = Services.io
+        .getProtocolHandler("file")
+        .QueryInterface(Ci.nsIFileProtocolHandler)
+        .getURLSpecFromDir(downloadDir);
+
+      downloadFolder.style.backgroundImage =
+        "url(moz-icon://" + urlSpec + "?size=16)";
+    }
+
+    return undefined;
+  },
+};
+
+Preferences.get("browser.download.dir").on(
+  "change",
+  gDownloadDirSection.readDownloadDirPref.bind(gDownloadDirSection)
+);
diff --git a/comm/mail/components/preferences/extensionControlled.js b/comm/mail/components/preferences/extensionControlled.js
new file mode 100644
index 0000000000..5dccb348bc
--- /dev/null
+++ b/comm/mail/components/preferences/extensionControlled.js
@@ -0,0 +1,129 @@
+/* - 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-globals-from preferences.js */
+
+"use strict";
+
+ChromeUtils.defineESModuleGetters(this, {
+  AddonManager: "resource://gre/modules/AddonManager.sys.mjs",
+  DeferredTask: "resource://gre/modules/DeferredTask.sys.mjs",
+  ExtensionSettingsStore:
+    "resource://gre/modules/ExtensionSettingsStore.sys.mjs",
+});
+
+const API_PROXY_PREFS = [
+  "network.proxy.type",
+  "network.proxy.http",
+  "network.proxy.http_port",
+  "network.proxy.share_proxy_settings",
+  "network.proxy.ssl",
+  "network.proxy.ssl_port",
+  "network.proxy.socks",
+  "network.proxy.socks_port",
+  "network.proxy.socks_version",
+  "network.proxy.socks_remote_dns",
+  "network.proxy.no_proxies_on",
+  "network.proxy.autoconfig_url",
+  "signon.autologin.proxy",
+];
+
+/**
+ * Check if a pref is being managed by an extension.
+ *
+ * NOTE: We only currently handle proxy.settings.
+ */
+/**
+ * Get the addon extension that is controlling the proxy settings.
+ *
+ * @returns - The found addon, or undefined if none was found.
+ */
+async function getControllingProxyExtensionAddon() {
+  await ExtensionSettingsStore.initialize();
+  let id = ExtensionSettingsStore.getSetting("prefs", "proxy.settings")?.id;
+  if (id) {
+    return AddonManager.getAddonByID(id);
+  }
+  return undefined;
+}
+
+/**
+ * Show or hide the proxy extension message depending on whether or not the
+ * proxy settings are controlled by an extension.
+ *
+ * @returns {boolean} - Whether the proxy settings are controlled by an
+ *   extension.
+ */
+async function handleControllingProxyExtension() {
+  let addon = await getControllingProxyExtensionAddon();
+  if (addon) {
+    showControllingProxyExtension(addon);
+  } else {
+    hideControllingProxyExtension();
+  }
+  return !!addon;
+}
+
+/**
+ * Show the proxy extension message.
+ *
+ * @param {object} addon - The addon extension that is currently controlling the
+ *   proxy settings.
+ * @param {string} addon.name - The addon name.
+ * @param {string} [addon.iconUrl] - The addon icon source.
+ */
+function showControllingProxyExtension(addon) {
+  let description = document.getElementById("proxyExtensionDescription");
+  description
+    .querySelector("img")
+    .setAttribute(
+      "src",
+      addon.iconUrl || "chrome://mozapps/skin/extensions/extensionGeneric.svg"
+    );
+  document.l10n.setAttributes(
+    description,
+    "proxy-settings-controlled-by-extension",
+    { name: addon.name }
+  );
+
+  document.getElementById("proxyExtensionContent").hidden = false;
+}
+
+/**
+ * Hide the proxy extension message.
+ */
+function hideControllingProxyExtension() {
+  document.getElementById("proxyExtensionContent").hidden = true;
+}
+
+/**
+ * Disable the addon extension that is currently controlling the proxy settings.
+ */
+function disableControllingProxyExtension() {
+  getControllingProxyExtensionAddon().then(addon => addon?.disable());
+}
+
+/**
+ * Start listening to the proxy settings, and update the UI accordingly.
+ *
+ * @param {object} container - The proxy container.
+ * @param {Function} container.updateProxySettingsUI - A callback to call
+ *   whenever the proxy settings change.
+ */
+function initializeProxyUI(container) {
+  let deferredUpdate = new DeferredTask(() => {
+    container.updateProxySettingsUI();
+  }, 10);
+  let proxyObserver = {
+    observe: (subject, topic, data) => {
+      if (API_PROXY_PREFS.includes(data)) {
+        deferredUpdate.arm();
+      }
+    },
+  };
+  Services.prefs.addObserver("", proxyObserver);
+  window.addEventListener("unload", () => {
+    Services.prefs.removeObserver("", proxyObserver);
+  });
+}
diff --git a/comm/mail/components/preferences/findInPage.js b/comm/mail/components/preferences/findInPage.js
new file mode 100644
index 0000000000..c69e8b50b6
--- /dev/null
+++ b/comm/mail/components/preferences/findInPage.js
@@ -0,0 +1,641 @@
+/* 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-globals-from extensionControlled.js */
+/* import-globals-from preferences.js */
+
+// A tweak to the standard <button> CE to use textContent on the <label>
+// inside the button, which allows the text to be highlighted when the user
+// is searching.
+
+const MozButton = customElements.get("button");
+class HighlightableButton extends MozButton {
+  static get inheritedAttributes() {
+    return Object.assign({}, super.inheritedAttributes, {
+      ".button-text": "text=label,accesskey,crop",
+    });
+  }
+}
+customElements.define("highlightable-button", HighlightableButton, {
+  extends: "button",
+});
+
+var gSearchResultsPane = {
+  listSearchTooltips: new Set(),
+  listSearchMenuitemIndicators: new Set(),
+  searchInput: null,
+  // A map of DOM Elements to a string of keywords used in search.
+  // XXX: We should invalidate this cache on `intl:app-locales-changed`.
+  searchKeywords: new WeakMap(),
+  inited: false,
+
+  init() {
+    if (this.inited) {
+      return;
+    }
+    this.inited = true;
+    this.searchInput = document.getElementById("searchInput");
+    this.searchInput.hidden = !Services.prefs.getBoolPref(
+      "browser.preferences.search"
+    );
+    if (!this.searchInput.hidden) {
+      this.searchInput.addEventListener("input", this);
+      this.searchInput.addEventListener("command", this);
+      window.addEventListener("DOMContentLoaded", () => {
+        this.searchInput.focus();
+      });
+      // Initialize other panes in an idle callback.
+      window.requestIdleCallback(() => this.initializeCategories());
+    }
+    let helpUrl =
+      Services.urlFormatter.formatURLPref("app.support.baseURL") +
+      "preferences";
+    let helpContainer = document.getElementById("need-help");
+    helpContainer.querySelector("a").href = helpUrl;
+  },
+
+  async handleEvent(event) {
+    // Ensure categories are initialized if idle callback didn't run soon enough.
+    await this.initializeCategories();
+    this.searchFunction(event);
+  },
+
+  /**
+   * Check that the text content contains the query string.
+   *
+   * @param {string} content the text content to be searched.
+   * @param {string} query the query string.
+   *
+   * @returns {boolean} true when the text content contains the query string else false.
+   */
+  queryMatchesContent(content, query) {
+    if (!content || !query) {
+      return false;
+    }
+    return content.toLowerCase().includes(query.toLowerCase());
+  },
+
+  categoriesInitialized: false,
+
+  /**
+   * Will attempt to initialize all uninitialized categories.
+   */
+  async initializeCategories() {
+    //  Initializing all the JS for all the tabs.
+    if (!this.categoriesInitialized) {
+      this.categoriesInitialized = true;
+      // Each element of gCategoryInits is a name.
+      for (let [name, category] of gCategoryInits) {
+        if (
+          (name != "paneCalendar" && !category.inited) ||
+          (calendarDeactivator.isCalendarActivated && !category.inited)
+        ) {
+          await category.init();
+        }
+      }
+      let lastSelected = Services.xulStore.getValue(
+        "about:preferences",
+        "paneDeck",
+        "lastSelected"
+      );
+      search(lastSelected, "data-category");
+    }
+  },
+
+  /**
+   * Finds and returns text nodes within node and all descendants.
+   * Iterates through all the sibilings of the node object and adds the sibilings
+   * to an array if sibling is a TEXT_NODE else checks the text nodes with in current node.
+   * Source - http://stackoverflow.com/questions/10730309/find-all-text-nodes-in-html-page
+   *
+   * @param {Node} node DOM element.
+   *
+   * @returns {Node[]} array of text nodes.
+   */
+  textNodeDescendants(node) {
+    if (!node) {
+      return [];
+    }
+    let all = [];
+    for (node = node.firstChild; node; node = node.nextSibling) {
+      if (node.nodeType === node.TEXT_NODE) {
+        all.push(node);
+      } else {
+        all = all.concat(this.textNodeDescendants(node));
+      }
+    }
+    return all;
+  },
+
+  /**
+   * This function is used to find words contained within the text nodes.
+   * We pass in the textNodes because they contain the text to be highlighted.
+   * We pass in the nodeSizes to tell exactly where highlighting need be done.
+   * When creating the range for highlighting, if the nodes are section is split
+   * by an access key, it is important to have the size of each of the nodes summed.
+   *
+   * @param {Node[]} textNodes List of DOM elements.
+   * @param {Node[]} nodeSizes Running size of text nodes. This will contain the same
+   *   number of elements as textNodes. The first element is the size of first textNode element.
+   *   For any nodes after, they will contain the summation of the nodes thus far in the array.
+   *   Example:
+   *   textNodes = [[This is ], [a], [n example]]
+   *   nodeSizes = [[8], [9], [18]]
+   *   This is used to determine the offset when highlighting.
+   * @param {string} textSearch Concatenation of textNodes's text content.
+   *    Example:
+   *    textNodes = [[This is ], [a], [n example]]
+   *    nodeSizes = "This is an example"
+   *    This is used when executing the regular expression.
+   * @param {string} searchPhrase word or words to search for.
+   *
+   * @returns {boolean} Returns true when atleast one instance of search phrase is found, otherwise false.
+   */
+  highlightMatches(textNodes, nodeSizes, textSearch, searchPhrase) {
+    if (!searchPhrase) {
+      return false;
+    }
+
+    let indices = [];
+    let i = -1;
+    while ((i = textSearch.indexOf(searchPhrase, i + 1)) >= 0) {
+      indices.push(i);
+    }
+
+    // Looping through each spot the searchPhrase is found in the concatenated string.dom-mutation-list.
+    for (let startValue of indices) {
+      let endValue = startValue + searchPhrase.length;
+      let startNode = null;
+      let endNode = null;
+      let nodeStartIndex = null;
+
+      // Determining the start and end node to highlight from.
+      for (let index = 0; index < nodeSizes.length; index++) {
+        let lengthNodes = nodeSizes[index];
+        // Determining the start node.
+        if (!startNode && lengthNodes >= startValue) {
+          startNode = textNodes[index];
+          nodeStartIndex = index;
+          // Calculating the offset when found query is not in the first node.
+          if (index > 0) {
+            startValue -= nodeSizes[index - 1];
+          }
+        }
+        // Determining the end node.
+        if (!endNode && lengthNodes >= endValue) {
+          endNode = textNodes[index];
+          // Calculating the offset when endNode is different from startNode
+          // or when endNode is not the first node.
+          if (index != nodeStartIndex || index > 0) {
+            endValue -= nodeSizes[index - 1];
+          }
+        }
+      }
+      let range = document.createRange();
+      range.setStart(startNode, startValue);
+      range.setEnd(endNode, endValue);
+      this.getFindSelection(startNode.ownerGlobal).addRange(range);
+    }
+
+    return !!indices.length;
+  },
+
+  /**
+   * Get the selection instance from given window.
+   *
+   * @param {object} win The window object points to frame's window.
+   */
+  getFindSelection(win) {
+    // Yuck. See bug 138068.
+    let docShell = win.docShell;
+
+    let controller = docShell
+      .QueryInterface(Ci.nsIInterfaceRequestor)
+      .getInterface(Ci.nsISelectionDisplay)
+      .QueryInterface(Ci.nsISelectionController);
+
+    let selection = controller.getSelection(
+      Ci.nsISelectionController.SELECTION_FIND
+    );
+    selection.setColors("currentColor", "#ffe900", "currentColor", "#003eaa");
+
+    return selection;
+  },
+
+  /**
+   * Shows or hides content according to search input.
+   *
+   * @param {object} event to search for filted query in.
+   */
+  async searchFunction(event) {
+    let query = event.target.value.trim().toLowerCase();
+    if (this.query == query) {
+      return;
+    }
+
+    let subQuery = this.query && query.includes(this.query);
+    this.query = query;
+
+    this.getFindSelection(window).removeAllRanges();
+    this.removeAllSearchTooltips();
+    this.removeAllSearchMenuitemIndicators();
+
+    let srHeader = document.getElementById("header-searchResults");
+    let noResultsEl = document.getElementById("no-results-message");
+    if (this.query) {
+      // Showing the Search Results Tag.
+      await gotoPref("paneSearchResults");
+      srHeader.hidden = false;
+
+      let resultsFound = false;
+
+      // Building the range for highlighted areas.
+      let rootPreferencesChildren = [
+        ...document.querySelectorAll(
+          "#paneDeck > *:not([data-hidden-from-search],script,stringbundle,commandset,keyset,linkset)"
+        ),
+      ];
+
+      if (subQuery) {
+        // Since the previous query is a subset of the current query,
+        // there is no need to check elements that is hidden already.
+        rootPreferencesChildren = rootPreferencesChildren.filter(
+          el => !el.hidden
+        );
+      }
+
+      // Attach the bindings for all children if they were not already visible.
+      for (let child of rootPreferencesChildren) {
+        if (child.hidden) {
+          child.classList.add("visually-hidden");
+          child.hidden = false;
+        }
+      }
+
+      let ts = performance.now();
+      let FRAME_THRESHOLD = 10;
+
+      // Showing or Hiding specific section depending on if words in query are found.
+      for (let child of rootPreferencesChildren) {
+        if (performance.now() - ts > FRAME_THRESHOLD) {
+          // Creating tooltips for all the instances found.
+          for (let anchorNode of this.listSearchTooltips) {
+            this.createSearchTooltip(anchorNode, this.query);
+          }
+          ts = await new Promise(resolve =>
+            window.requestAnimationFrame(resolve)
+          );
+          if (query !== this.query) {
+            return;
+          }
+        }
+
+        if (
+          !child.classList.contains("header") &&
+          !child.classList.contains("subcategory") &&
+          (await this.searchWithinNode(child, this.query))
+        ) {
+          child.classList.remove("visually-hidden");
+
+          // Show the preceding search-header if one exists.
+          let groupbox = child.closest("groupbox");
+          let groupHeader =
+            groupbox && groupbox.querySelector(".search-header");
+          if (groupHeader) {
+            groupHeader.hidden = false;
+          }
+
+          resultsFound = true;
+        } else {
+          child.classList.add("visually-hidden");
+        }
+      }
+
+      noResultsEl.hidden = !!resultsFound;
+      noResultsEl.setAttribute("query", this.query);
+      // XXX: This is potentially racy in case where Fluent retranslates the
+      // message and ereases the query within.
+      // The feature is not yet supported, but we should fix for it before
+      // we enable it. See bug 1446389 for details.
+      let msgQueryElem = document.getElementById("sorry-message-query");
+      msgQueryElem.textContent = this.query;
+      if (resultsFound) {
+        // Creating tooltips for all the instances found.
+        for (let anchorNode of this.listSearchTooltips) {
+          this.createSearchTooltip(anchorNode, this.query);
+        }
+      }
+    } else {
+      noResultsEl.hidden = true;
+      document.getElementById("sorry-message-query").textContent = "";
+      // Going back to General when cleared.
+      await gotoPref("paneGeneral");
+      srHeader.hidden = true;
+
+      // Hide some special second level headers in normal view.
+      for (let element of document.querySelectorAll(".search-header")) {
+        element.hidden = true;
+      }
+    }
+
+    window.dispatchEvent(
+      new CustomEvent("PreferencesSearchCompleted", { detail: query })
+    );
+  },
+
+  /**
+   * Finding leaf nodes and checking their content for words to search,
+   * It is a recursive function.
+   *
+   * @param {Node} nodeObject DOM Element.
+   * @param {string} searchPhrase
+   *
+   * @returns {boolean} Returns true when found in at least one childNode, false otherwise.
+   */
+  async searchWithinNode(nodeObject, searchPhrase) {
+    let matchesFound = false;
+    if (
+      nodeObject.childElementCount == 0 ||
+      nodeObject.tagName == "button" ||
+      nodeObject.tagName == "label" ||
+      nodeObject.tagName == "description" ||
+      nodeObject.tagName == "menulist" ||
+      nodeObject.tagName == "menuitem"
+    ) {
+      let simpleTextNodes = this.textNodeDescendants(nodeObject);
+      for (let node of simpleTextNodes) {
+        let result = this.highlightMatches(
+          [node],
+          [node.length],
+          node.textContent.toLowerCase(),
+          searchPhrase
+        );
+        matchesFound = matchesFound || result;
+      }
+
+      // Collecting data from anonymous content / label / description.
+      let nodeSizes = [];
+      let allNodeText = "";
+      let runningSize = 0;
+
+      let accessKeyTextNodes = [];
+
+      if (
+        nodeObject.tagName == "label" ||
+        nodeObject.tagName == "description"
+      ) {
+        accessKeyTextNodes.push(...simpleTextNodes);
+      }
+
+      for (let node of accessKeyTextNodes) {
+        runningSize += node.textContent.length;
+        allNodeText += node.textContent;
+        nodeSizes.push(runningSize);
+      }
+
+      // Access key are presented.
+      let complexTextNodesResult = this.highlightMatches(
+        accessKeyTextNodes,
+        nodeSizes,
+        allNodeText.toLowerCase(),
+        searchPhrase
+      );
+
+      // Searching some elements, such as xul:button, have a 'label' attribute
+      // that contains the user-visible text.
+      let labelResult = this.queryMatchesContent(
+        nodeObject.getAttribute("label"),
+        searchPhrase
+      );
+
+      // Searching some elements, such as xul:label, store their user-visible
+      // text in a "value" attribute. Value will be skipped for menuitem since
+      // value in menuitem could represent index number to distinct each item.
+      let valueResult =
+        nodeObject.tagName !== "menuitem" && nodeObject.tagName !== "radio"
+          ? this.queryMatchesContent(
+              nodeObject.getAttribute("value"),
+              searchPhrase
+            )
+          : false;
+
+      // Searching some elements, such as xul:button, buttons to open subdialogs
+      // using l10n ids.
+      let keywordsResult =
+        nodeObject.hasAttribute("search-l10n-ids") &&
+        (await this.matchesSearchL10nIDs(nodeObject, searchPhrase));
+
+      if (!keywordsResult) {
+        // Searching some elements, such as xul:button, buttons to open subdialogs
+        // using searchkeywords attribute.
+        keywordsResult =
+          !keywordsResult &&
+          nodeObject.hasAttribute("searchkeywords") &&
+          this.queryMatchesContent(
+            nodeObject.getAttribute("searchkeywords"),
+            searchPhrase
+          );
+      }
+
+      // Creating tooltips for buttons.
+      if (
+        keywordsResult &&
+        (nodeObject.tagName === "button" || nodeObject.tagName == "menulist")
+      ) {
+        this.listSearchTooltips.add(nodeObject);
+      }
+
+      if (keywordsResult && nodeObject.tagName === "menuitem") {
+        nodeObject.setAttribute("indicator", "true");
+        this.listSearchMenuitemIndicators.add(nodeObject);
+        let menulist = nodeObject.closest("menulist");
+
+        menulist.setAttribute("indicator", "true");
+        this.listSearchMenuitemIndicators.add(menulist);
+      }
+
+      if (
+        (nodeObject.tagName == "menulist" ||
+          nodeObject.tagName == "menuitem") &&
+        (labelResult || valueResult || keywordsResult)
+      ) {
+        nodeObject.setAttribute("highlightable", "true");
+      }
+
+      matchesFound =
+        matchesFound ||
+        complexTextNodesResult ||
+        labelResult ||
+        valueResult ||
+        keywordsResult;
+    }
+
+    for (let i = 0; i < nodeObject.childNodes.length; i++) {
+      let result = await this.searchChildNodeIfVisible(
+        nodeObject,
+        i,
+        searchPhrase
+      );
+      matchesFound = matchesFound || result;
+    }
+    return matchesFound;
+  },
+
+  /**
+   * Search for a phrase within a child node if it is visible.
+   *
+   * @param {Node} nodeObject The parent DOM Element.
+   * @param {number} index The index for the childNode.
+   * @param {string} searchPhrase
+   *
+   * @returns {boolean} Returns true when found the specific childNode, false otherwise
+   */
+  async searchChildNodeIfVisible(nodeObject, index, searchPhrase) {
+    let result = false;
+    if (
+      !nodeObject.childNodes[index].hidden &&
+      nodeObject.getAttribute("data-hidden-from-search") !== "true"
+    ) {
+      result = await this.searchWithinNode(
+        nodeObject.childNodes[index],
+        searchPhrase
+      );
+      // Creating tooltips for menulist element.
+      if (result && nodeObject.tagName === "menulist") {
+        this.listSearchTooltips.add(nodeObject);
+      }
+    }
+    return result;
+  },
+
+  /**
+   * Search for a phrase in l10n messages associated with the element.
+   *
+   * @param {Node} nodeObject The parent DOM Element.
+   * @param {string} searchPhrase.
+   * @returns {boolean} true when the text content contains the query string else false.
+   */
+  async matchesSearchL10nIDs(nodeObject, searchPhrase) {
+    if (!this.searchKeywords.has(nodeObject)) {
+      // The `search-l10n-ids` attribute is a comma-separated list of
+      // l10n ids. It may also uses a dot notation to specify an attribute
+      // of the message to be used.
+      //
+      // Example: "containers-add-button.label, user-context-personal".
+      //
+      // The result is an array of arrays of l10n ids and optionally attribute names.
+      //
+      // Example: [["containers-add-button", "label"], ["user-context-personal"]]
+      const refs = nodeObject
+        .getAttribute("search-l10n-ids")
+        .split(",")
+        .map(s => s.trim().split("."))
+        .filter(s => !!s[0].length);
+
+      const messages = await document.l10n.formatMessages(
+        refs.map(ref => ({ id: ref[0] }))
+      );
+
+      // Map the localized messages taking value or a selected attribute and
+      // building a string of concatenated translated strings out of it.
+      let keywords = messages
+        .map((msg, i) => {
+          let [refId, refAttr] = refs[i];
+          if (!msg) {
+            console.error(`Missing search l10n id "${refId}"`);
+            return null;
+          }
+          if (refAttr) {
+            let attr =
+              msg.attributes && msg.attributes.find(a => a.name === refAttr);
+            if (!attr) {
+              console.error(`Missing search l10n id "${refId}.${refAttr}"`);
+              return null;
+            }
+            if (attr.value === "") {
+              console.error(
+                `Empty value added to search-l10n-ids "${refId}.${refAttr}"`
+              );
+            }
+            return attr.value;
+          }
+          if (msg.value === "") {
+            console.error(`Empty value added to search-l10n-ids "${refId}"`);
+          }
+          return msg.value;
+        })
+        .filter(keyword => keyword !== null)
+        .join(" ");
+
+      this.searchKeywords.set(nodeObject, keywords);
+      return this.queryMatchesContent(keywords, searchPhrase);
+    }
+
+    return this.queryMatchesContent(
+      this.searchKeywords.get(nodeObject),
+      searchPhrase
+    );
+  },
+
+  /**
+   * Inserting a div structure infront of the DOM element matched textContent.
+   * Then calculation the offsets to position the tooltip in the correct place.
+   *
+   * @param {Node} anchorNode DOM Element.
+   * @param {string} query Word or words that are being searched for.
+   */
+  createSearchTooltip(anchorNode, query) {
+    if (anchorNode.tooltipNode) {
+      return;
+    }
+    let searchTooltip = anchorNode.ownerDocument.createElement("span");
+    let searchTooltipText = anchorNode.ownerDocument.createElement("span");
+    searchTooltip.className = "search-tooltip";
+    searchTooltipText.textContent = query;
+    searchTooltip.appendChild(searchTooltipText);
+
+    // Set tooltipNode property to track corresponded tooltip node.
+    anchorNode.tooltipNode = searchTooltip;
+    anchorNode.parentElement.classList.add("search-tooltip-parent");
+    anchorNode.parentElement.appendChild(searchTooltip);
+
+    this.calculateTooltipPosition(anchorNode);
+  },
+
+  calculateTooltipPosition(anchorNode) {
+    let searchTooltip = anchorNode.tooltipNode;
+    // In order to get the up-to-date position of each of the nodes that we're
+    // putting tooltips on, we have to flush layout intentionally, and that
+    // this is the result of a XUL limitation (bug 1363730).
+    let tooltipRect = searchTooltip.getBoundingClientRect();
+    searchTooltip.style.setProperty(
+      "left",
+      `calc(50% - ${tooltipRect.width / 2}px)`
+    );
+  },
+
+  /**
+   * Remove all search tooltips.
+   */
+  removeAllSearchTooltips() {
+    for (let anchorNode of this.listSearchTooltips) {
+      anchorNode.parentElement.classList.remove("search-tooltip-parent");
+      if (anchorNode.tooltipNode) {
+        anchorNode.tooltipNode.remove();
+      }
+      anchorNode.tooltipNode = null;
+    }
+    this.listSearchTooltips.clear();
+  },
+
+  /**
+   * Remove all indicators on menuitem.
+   */
+  removeAllSearchMenuitemIndicators() {
+    for (let node of this.listSearchMenuitemIndicators) {
+      node.removeAttribute("indicator");
+    }
+    this.listSearchMenuitemIndicators.clear();
+  },
+};
diff --git a/comm/mail/components/preferences/fonts.js b/comm/mail/components/preferences/fonts.js
new file mode 100644
index 0000000000..d6a4c1308e
--- /dev/null
+++ b/comm/mail/components/preferences/fonts.js
@@ -0,0 +1,196 @@
+/* -*- Mode: JavaScript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/content/preferencesBindings.js
+/* globals Preferences */
+// toolkit/mozapps/preferences/fontbuilder.js
+/* globals FontBuilder */
+
+var kDefaultFontType = "font.default.%LANG%";
+var kFontNameFmtSerif = "font.name.serif.%LANG%";
+var kFontNameFmtSansSerif = "font.name.sans-serif.%LANG%";
+var kFontNameFmtMonospace = "font.name.monospace.%LANG%";
+var kFontNameListFmtSerif = "font.name-list.serif.%LANG%";
+var kFontNameListFmtSansSerif = "font.name-list.sans-serif.%LANG%";
+var kFontNameListFmtMonospace = "font.name-list.monospace.%LANG%";
+var kFontSizeFmtVariable = "font.size.variable.%LANG%";
+var kFontSizeFmtFixed = "font.size.monospace.%LANG%";
+var kFontMinSizeFmt = "font.minimum-size.%LANG%";
+
+Preferences.addAll([
+  { id: "font.language.group", type: "wstring" },
+  { id: "browser.display.use_document_fonts", type: "int" },
+  { id: "mail.fixed_width_messages", type: "bool" },
+]);
+
+var gFontsDialog = {
+  _selectLanguageGroupPromise: Promise.resolve(),
+
+  init() {
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("selectLangs"),
+      () => gFontsDialog.readFontLanguageGroup()
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("serif"),
+      element => FontBuilder.readFontSelection(element)
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("sans-serif"),
+      element => FontBuilder.readFontSelection(element)
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("monospace"),
+      element => FontBuilder.readFontSelection(element)
+    );
+
+    let element = document.getElementById("useDocumentFonts");
+    Preferences.addSyncFromPrefListener(element, () =>
+      gFontsDialog.readUseDocumentFonts()
+    );
+    Preferences.addSyncToPrefListener(element, () =>
+      gFontsDialog.writeUseDocumentFonts()
+    );
+
+    element = document.getElementById("mailFixedWidthMessages");
+    Preferences.addSyncFromPrefListener(element, () =>
+      gFontsDialog.readFixedWidthForPlainText()
+    );
+    Preferences.addSyncToPrefListener(element, () =>
+      gFontsDialog.writeFixedWidthForPlainText()
+    );
+  },
+
+  _selectLanguageGroup(aLanguageGroup) {
+    this._selectLanguageGroupPromise = (async () => {
+      // Avoid overlapping language group selections by awaiting the resolution
+      // of the previous one.  We do this because this function is re-entrant,
+      // as inserting <preference> elements into the DOM sometimes triggers a call
+      // back into this function.  And since this function is also asynchronous,
+      // that call can enter this function before the previous run has completed,
+      // which would corrupt the font menulists.  Awaiting the previous call's
+      // resolution avoids that fate.
+      await this._selectLanguageGroupPromise;
+
+      var prefs = [
+        {
+          format: kDefaultFontType,
+          type: "string",
+          element: "defaultFontType",
+          fonttype: null,
+        },
+        {
+          format: kFontNameFmtSerif,
+          type: "fontname",
+          element: "serif",
+          fonttype: "serif",
+        },
+        {
+          format: kFontNameFmtSansSerif,
+          type: "fontname",
+          element: "sans-serif",
+          fonttype: "sans-serif",
+        },
+        {
+          format: kFontNameFmtMonospace,
+          type: "fontname",
+          element: "monospace",
+          fonttype: "monospace",
+        },
+        {
+          format: kFontNameListFmtSerif,
+          type: "unichar",
+          element: null,
+          fonttype: "serif",
+        },
+        {
+          format: kFontNameListFmtSansSerif,
+          type: "unichar",
+          element: null,
+          fonttype: "sans-serif",
+        },
+        {
+          format: kFontNameListFmtMonospace,
+          type: "unichar",
+          element: null,
+          fonttype: "monospace",
+        },
+        {
+          format: kFontSizeFmtVariable,
+          type: "int",
+          element: "sizeVar",
+          fonttype: null,
+        },
+        {
+          format: kFontSizeFmtFixed,
+          type: "int",
+          element: "sizeMono",
+          fonttype: null,
+        },
+        {
+          format: kFontMinSizeFmt,
+          type: "int",
+          element: "minSize",
+          fonttype: null,
+        },
+      ];
+      for (var i = 0; i < prefs.length; ++i) {
+        var name = prefs[i].format.replace(/%LANG%/, aLanguageGroup);
+        var preference = Preferences.get(name);
+        if (!preference) {
+          preference = Preferences.add({ id: name, type: prefs[i].type });
+        }
+
+        if (!prefs[i].element) {
+          continue;
+        }
+
+        var element = document.getElementById(prefs[i].element);
+        if (element) {
+          element.setAttribute("preference", preference.id);
+
+          if (prefs[i].fonttype) {
+            await FontBuilder.buildFontList(
+              aLanguageGroup,
+              prefs[i].fonttype,
+              element
+            );
+          }
+          preference.setElementValue(element);
+        }
+      }
+    })().catch(console.error);
+  },
+
+  readFontLanguageGroup() {
+    var languagePref = Preferences.get("font.language.group");
+    this._selectLanguageGroup(languagePref.value);
+    return undefined;
+  },
+
+  readUseDocumentFonts() {
+    var preference = Preferences.get("browser.display.use_document_fonts");
+    return preference.value == 1;
+  },
+
+  writeUseDocumentFonts() {
+    var useDocumentFonts = document.getElementById("useDocumentFonts");
+    return useDocumentFonts.checked ? 1 : 0;
+  },
+
+  readFixedWidthForPlainText() {
+    var preference = Preferences.get("mail.fixed_width_messages");
+    return preference.value == 1;
+  },
+
+  writeFixedWidthForPlainText() {
+    var mailFixedWidthMessages = document.getElementById(
+      "mailFixedWidthMessages"
+    );
+    return mailFixedWidthMessages.checked;
+  },
+};
+
+window.addEventListener("load", () => gFontsDialog.init());
diff --git a/comm/mail/components/preferences/fonts.xhtml b/comm/mail/components/preferences/fonts.xhtml
new file mode 100644
index 0000000000..4bb793a04d
--- /dev/null
+++ b/comm/mail/components/preferences/fonts.xhtml
@@ -0,0 +1,337 @@
+<?xml version="1.0"?>
+<!-- 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 https://mozilla.org/MPL/2.0/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+
+<!DOCTYPE html>
+<html
+  id="FontsDialog"
+  xmlns="http://www.w3.org/1999/xhtml"
+  xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  type="child"
+  persist="lastSelected"
+  scrolling="false"
+  style="min-width: 60ch"
+>
+  <head>
+    <title data-l10n-id="fonts-dialog-title"></title>
+    <link rel="localization" href="messenger/preferences/fonts.ftl" />
+    <script
+      defer="defer"
+      src="chrome://global/content/preferencesBindings.js"
+    ></script>
+    <script
+      defer="defer"
+      src="chrome://mozapps/content/preferences/fontbuilder.js"
+    ></script>
+    <script
+      defer="defer"
+      src="chrome://messenger/content/menulist-charsetpicker.js"
+    ></script>
+    <script
+      defer="defer"
+      src="chrome://messenger/content/preferences/fonts.js"
+    ></script>
+  </head>
+  <html:body
+    xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  >
+    <dialog buttons="accept,cancel" style="min-height: 100vh">
+      <keyset>
+        <key
+          data-l10n-id="fonts-window-close"
+          modifiers="accel"
+          oncommand="Preferences.close(event)"
+        />
+      </keyset>
+
+      <html:fieldset>
+        <!-- title row -->
+        <hbox>
+          <hbox align="center" pack="end">
+            <label
+              id="fontsTitle"
+              control="selectLangs"
+              data-l10n-id="fonts-language-legend"
+            />
+          </hbox>
+          <menulist id="selectLangs" flex="1" preference="font.language.group">
+            <menupopup>
+              <menuitem value="ar" data-l10n-id="font-language-group-arabic" />
+              <menuitem
+                value="x-armn"
+                data-l10n-id="font-language-group-armenian"
+              />
+              <menuitem
+                value="x-beng"
+                data-l10n-id="font-language-group-bengali"
+              />
+              <menuitem
+                value="zh-CN"
+                data-l10n-id="font-language-group-simpl-chinese"
+              />
+              <menuitem
+                value="zh-HK"
+                data-l10n-id="font-language-group-trad-chinese-hk"
+              />
+              <menuitem
+                value="zh-TW"
+                data-l10n-id="font-language-group-trad-chinese"
+              />
+              <menuitem
+                value="x-cyrillic"
+                data-l10n-id="font-language-group-cyrillic"
+              />
+              <menuitem
+                value="x-devanagari"
+                data-l10n-id="font-language-group-devanagari"
+              />
+              <menuitem
+                value="x-ethi"
+                data-l10n-id="font-language-group-ethiopic"
+              />
+              <menuitem
+                value="x-geor"
+                data-l10n-id="font-language-group-georgian"
+              />
+              <menuitem value="el" data-l10n-id="font-language-group-el" />
+              <menuitem
+                value="x-gujr"
+                data-l10n-id="font-language-group-gujarati"
+              />
+              <menuitem
+                value="x-guru"
+                data-l10n-id="font-language-group-gurmukhi"
+              />
+              <menuitem value="he" data-l10n-id="font-language-group-hebrew" />
+              <menuitem
+                value="ja"
+                data-l10n-id="font-language-group-japanese"
+              />
+              <menuitem
+                value="x-knda"
+                data-l10n-id="font-language-group-kannada"
+              />
+              <menuitem
+                value="x-khmr"
+                data-l10n-id="font-language-group-khmer"
+              />
+              <menuitem value="ko" data-l10n-id="font-language-group-korean" />
+              <menuitem
+                value="x-western"
+                data-l10n-id="font-language-group-latin"
+              />
+              <menuitem
+                value="x-mlym"
+                data-l10n-id="font-language-group-malayalam"
+              />
+              <menuitem
+                value="x-math"
+                data-l10n-id="font-language-group-math"
+              />
+              <menuitem
+                value="x-orya"
+                data-l10n-id="font-language-group-odia"
+              />
+              <menuitem
+                value="x-sinh"
+                data-l10n-id="font-language-group-sinhala"
+              />
+              <menuitem
+                value="x-tamil"
+                data-l10n-id="font-language-group-tamil"
+              />
+              <menuitem
+                value="x-telu"
+                data-l10n-id="font-language-group-telugu"
+              />
+              <menuitem value="th" data-l10n-id="font-language-group-thai" />
+              <menuitem
+                value="x-tibt"
+                data-l10n-id="font-language-group-tibetan"
+              />
+              <menuitem
+                value="x-cans"
+                data-l10n-id="font-language-group-canadian"
+              />
+              <menuitem
+                value="x-unicode"
+                data-l10n-id="font-language-group-other"
+              />
+            </menupopup>
+          </menulist>
+        </hbox>
+        <separator />
+        <box id="font-chooser-group">
+          <!-- proportional row -->
+          <hbox align="center" pack="end">
+            <label data-l10n-id="fonts-proportional-label" />
+          </hbox>
+          <menulist id="defaultFontType">
+            <menupopup>
+              <menuitem value="serif" data-l10n-id="default-font-serif" />
+              <menuitem
+                value="sans-serif"
+                data-l10n-id="default-font-sans-serif"
+              />
+            </menupopup>
+          </menulist>
+          <hbox align="center" pack="end">
+            <label
+              control="sizeVar"
+              data-l10n-id="font-size-proportional-label"
+              class="startSpacing"
+            />
+          </hbox>
+          <menulist id="sizeVar" delayprefsave="true">
+            <menupopup>
+              <menuitem value="9" label="9" />
+              <menuitem value="10" label="10" />
+              <menuitem value="11" label="11" />
+              <menuitem value="12" label="12" />
+              <menuitem value="13" label="13" />
+              <menuitem value="14" label="14" />
+              <menuitem value="15" label="15" />
+              <menuitem value="16" label="16" />
+              <menuitem value="17" label="17" />
+              <menuitem value="18" label="18" />
+              <menuitem value="20" label="20" />
+              <menuitem value="22" label="22" />
+              <menuitem value="24" label="24" />
+              <menuitem value="26" label="26" />
+              <menuitem value="28" label="28" />
+              <menuitem value="30" label="30" />
+              <menuitem value="32" label="32" />
+              <menuitem value="34" label="34" />
+              <menuitem value="36" label="36" />
+              <menuitem value="40" label="40" />
+              <menuitem value="44" label="44" />
+              <menuitem value="48" label="48" />
+              <menuitem value="56" label="56" />
+              <menuitem value="64" label="64" />
+              <menuitem value="72" label="72" />
+            </menupopup>
+          </menulist>
+
+          <!-- serif row -->
+          <hbox align="center" pack="end">
+            <label control="serif" data-l10n-id="font-serif-label" />
+          </hbox>
+          <menulist id="serif" delayprefsave="true" />
+          <spacer />
+          <spacer />
+
+          <!-- sans-serif row -->
+          <hbox align="center" pack="end">
+            <label control="sans-serif" data-l10n-id="font-sans-serif-label" />
+          </hbox>
+          <menulist id="sans-serif" delayprefsave="true" />
+          <spacer />
+          <spacer />
+
+          <!-- monospace row -->
+          <hbox align="center" pack="end">
+            <label control="monospace" data-l10n-id="font-monospace-label" />
+          </hbox>
+          <menulist id="monospace" crop="end" delayprefsave="true" />
+          <hbox align="center" pack="end">
+            <label
+              control="sizeMono"
+              data-l10n-id="font-size-monospace-label"
+              class="startSpacing"
+            />
+          </hbox>
+          <menulist id="sizeMono" delayprefsave="true">
+            <menupopup>
+              <menuitem value="9" label="9" />
+              <menuitem value="10" label="10" />
+              <menuitem value="11" label="11" />
+              <menuitem value="12" label="12" />
+              <menuitem value="13" label="13" />
+              <menuitem value="14" label="14" />
+              <menuitem value="15" label="15" />
+              <menuitem value="16" label="16" />
+              <menuitem value="17" label="17" />
+              <menuitem value="18" label="18" />
+              <menuitem value="20" label="20" />
+              <menuitem value="22" label="22" />
+              <menuitem value="24" label="24" />
+              <menuitem value="26" label="26" />
+              <menuitem value="28" label="28" />
+              <menuitem value="30" label="30" />
+              <menuitem value="32" label="32" />
+              <menuitem value="34" label="34" />
+              <menuitem value="36" label="36" />
+              <menuitem value="40" label="40" />
+              <menuitem value="44" label="44" />
+              <menuitem value="48" label="48" />
+              <menuitem value="56" label="56" />
+              <menuitem value="64" label="64" />
+              <menuitem value="72" label="72" />
+            </menupopup>
+          </menulist>
+        </box>
+
+        <separator class="thin" />
+
+        <hbox flex="1">
+          <spacer flex="1" />
+          <hbox align="center" pack="end">
+            <label data-l10n-id="font-min-size-label" control="minSize" />
+            <menulist id="minSize">
+              <menupopup>
+                <menuitem value="0" data-l10n-id="min-size-none" />
+                <menuitem value="9" label="9" />
+                <menuitem value="10" label="10" />
+                <menuitem value="11" label="11" />
+                <menuitem value="12" label="12" />
+                <menuitem value="13" label="13" />
+                <menuitem value="14" label="14" />
+                <menuitem value="15" label="15" />
+                <menuitem value="16" label="16" />
+                <menuitem value="17" label="17" />
+                <menuitem value="18" label="18" />
+                <menuitem value="20" label="20" />
+                <menuitem value="22" label="22" />
+                <menuitem value="24" label="24" />
+                <menuitem value="26" label="26" />
+                <menuitem value="28" label="28" />
+                <menuitem value="30" label="30" />
+                <menuitem value="32" label="32" />
+                <menuitem value="34" label="34" />
+                <menuitem value="36" label="36" />
+                <menuitem value="40" label="40" />
+                <menuitem value="44" label="44" />
+                <menuitem value="48" label="48" />
+                <menuitem value="56" label="56" />
+                <menuitem value="64" label="64" />
+                <menuitem value="72" label="72" />
+              </menupopup>
+            </menulist>
+          </hbox>
+        </hbox>
+      </html:fieldset>
+
+      <html:fieldset>
+        <html:legend data-l10n-id="font-control-legend"></html:legend>
+        <hbox>
+          <checkbox
+            id="useDocumentFonts"
+            data-l10n-id="use-document-fonts-checkbox"
+            preference="browser.display.use_document_fonts"
+          />
+        </hbox>
+        <hbox>
+          <checkbox
+            id="mailFixedWidthMessages"
+            data-l10n-id="use-fixed-width-plain-checkbox"
+            preference="mail.fixed_width_messages"
+          />
+        </hbox>
+      </html:fieldset>
+    </dialog>
+  </html:body>
+</html>
diff --git a/comm/mail/components/preferences/general.inc.xhtml b/comm/mail/components/preferences/general.inc.xhtml
new file mode 100644
index 0000000000..438624649b
--- /dev/null
+++ b/comm/mail/components/preferences/general.inc.xhtml
@@ -0,0 +1,1096 @@
+# 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/.
+  <script src="chrome://communicator/content/utilityOverlay.js" />
+  <script src="chrome://messenger/content/preferences/general.js"/>
+  <script src="chrome://mozapps/content/preferences/fontbuilder.js"/>
+
+  <commandset id="appPaneCommandSet">
+    <command id="cmd_delete"
+             oncommand="gGeneralPane.onDelete();"/>
+  </commandset>
+
+  <keyset id="appPaneKeyset">
+    <key keycode="VK_BACK" modifiers="any" command="cmd_delete"/>
+    <key keycode="VK_DELETE" modifiers="any" command="cmd_delete"/>
+  </keyset>
+
+  <keyset>
+    <key data-l10n-id="focus-search-shortcut" modifiers="accel"
+         oncommand="gGeneralPane.focusFilterBox();"/>
+    <key data-l10n-id="focus-search-shortcut-alt" modifiers="accel"
+         oncommand="gGeneralPane.focusFilterBox();"/>
+  </keyset>
+
+  <stringbundle id="bundlePreferences" src="chrome://messenger/locale/preferences/preferences.properties"/>
+#ifdef HAVE_SHELL_SERVICE
+  <stringbundle id="bundleBrand" src="chrome://branding/locale/brand.properties"/>
+#endif
+  <html:template id="paneGeneral">
+    <hbox id="generalCategory"
+          class="subcategory"
+          data-category="paneGeneral">
+      <html:h1 data-l10n-id="pane-general-title"/>
+    </hbox>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <html:legend data-l10n-id="general-legend"></html:legend>
+      <vbox>
+        <hbox align="start">
+          <checkbox id="mailnewsStartPageEnabled"
+                    preference="mailnews.start_page.enabled"
+                    data-l10n-id="start-page-label"/>
+        </hbox>
+        <hbox align="center" class="input-container">
+          <label data-l10n-id="location-label" control="mailnewsStartPageUrl"/>
+          <html:input id="mailnewsStartPageUrl"
+                      type="url"
+                      preference="mailnews.start_page.url"/>
+          <button is="highlightable-button" id="browseForStartPageUrl"
+                  data-l10n-id="restore-default-label"
+                  oncommand="gGeneralPane.restoreDefaultStartPage();">
+          </button>
+        </hbox>
+      </vbox>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <html:legend data-l10n-id="default-search-engine"></html:legend>
+      <hbox align="center">
+        <hbox>
+          <menulist id="defaultWebSearch">
+            <menupopup id="defaultWebSearchPopup"/>
+          </menulist>
+        </hbox>
+        <button is="highlightable-button" id="addSearchEngine"
+                data-l10n-id="add-web-search-engine"
+                oncommand="gGeneralPane.addSearchEngine();"/>
+        <button is="highlightable-button" id="removeSearchEngine"
+                data-l10n-id="remove-search-engine"
+                oncommand="gGeneralPane.removeSearchEngine();"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+#ifdef HAVE_SHELL_SERVICE
+    <html:div data-category="paneGeneral">
+    <html:fieldset id="systemDefaultsGroup" data-category="paneGeneral">
+      <html:legend data-l10n-id="system-integration-legend"></html:legend>
+      <vbox>
+      <hbox id="checkDefaultBox" align="center">
+        <checkbox id="alwaysCheckDefault"
+                  preference="mail.shell.checkDefaultClient"
+                  data-l10n-id="always-check-default"/>
+        <spacer flex="1"/>
+        <hbox>
+          <button is="highlightable-button" id="checkDefaultButton"
+                  data-l10n-id="check-default-button"
+                  oncommand="gGeneralPane.checkDefaultNow();"
+                  preference="pref.general.disable_button.default_mail"
+                  search-l10n-ids="
+                    system-integration-title.title,
+                    system-integration-dialog.buttonlabelaccept,
+                    system-integration-dialog.buttonlabelcancel,
+                    system-integration-dialog.buttonlabelcancel2,
+                    default-client-intro,
+                    unset-default-tooltip,
+                    checkbox-email-label.label,
+                    checkbox-newsgroups-label.label,
+                    checkbox-feeds-label.label,
+                    system-search-integration-label.label,
+                    check-on-startup-label.label"/>
+        </hbox>
+      </hbox>
+#ifdef XP_WIN
+      <hbox align="start">
+        <checkbox data-l10n-id="minimize-to-tray-label"
+                  preference="mail.minimizeToTray"/>
+      </hbox>
+#endif
+      <hbox id="searchIntegrationContainer">
+        <checkbox id="searchIntegration"
+                  preference="searchintegration.enable"
+                  data-l10n-id="search-integration-label"/>
+      </hbox>
+      </vbox>
+    </html:fieldset>
+    </html:div>
+#endif
+
+    <hbox id="languageAndAppearanceCategory"
+          class="subcategory"
+          data-category="paneGeneral">
+      <html:h1 data-l10n-id="general-language-and-appearance-header"/>
+    </hbox>
+
+    <!-- Window layout -->
+    <html:div data-category="paneGeneral">
+    <html:fieldset id="layoutGroup" data-category="paneGeneral">
+      <html:legend data-l10n-id="window-layout-legend"></html:legend>
+      <hbox>
+        <checkbox id="drawInTitlebar"
+                  data-l10n-id="draw-in-titlebar-label"
+                  preference="mail.tabs.drawInTitlebar"/>
+        <spacer flex="1"/>
+      </hbox>
+      <hbox>
+        <vbox>
+          <checkbox id="autoHideTabbar"
+                    data-l10n-id="auto-hide-tabbar-label"
+                    preference="mail.tabs.autoHide"/>
+          <description data-l10n-id="auto-hide-tabbar-description"
+                       class="tip-caption indent"/>
+        </vbox>
+        <spacer flex="1"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <!-- Fonts and Colors -->
+    <html:div data-category="paneGeneral">
+    <html:fieldset id="fontsGroup" data-category="paneGeneral">
+      <html:legend data-l10n-id="fonts-legend"></html:legend>
+
+      <hbox id="fontSettings" flex="1">
+        <vbox id="fontRow" flex="1">
+          <hbox align="center">
+            <label data-l10n-id="default-font-label" control="defaultFont"/>
+            <hbox flex="1">
+              <menulist id="defaultFont" flex="1" sizetopopup="pref" crop="center">
+                <menupopup crop="center"/>
+              </menulist>
+            </hbox>
+            <label data-l10n-id="default-size-label" control="defaultFontSize"/>
+            <hbox flex="1">
+              <menulist id="defaultFontSize" flex="1">
+                <menupopup crop="center">
+                  <menuitem value="9" label="9"/>
+                  <menuitem value="10" label="10"/>
+                  <menuitem value="11" label="11"/>
+                  <menuitem value="12" label="12"/>
+                  <menuitem value="13" label="13"/>
+                  <menuitem value="14" label="14"/>
+                  <menuitem value="15" label="15"/>
+                  <menuitem value="16" label="16"/>
+                  <menuitem value="17" label="17"/>
+                  <menuitem value="18" label="18"/>
+                  <menuitem value="20" label="20"/>
+                  <menuitem value="22" label="22"/>
+                  <menuitem value="24" label="24"/>
+                  <menuitem value="26" label="26"/>
+                  <menuitem value="28" label="28"/>
+                  <menuitem value="30" label="30"/>
+                  <menuitem value="32" label="32"/>
+                  <menuitem value="34" label="34"/>
+                  <menuitem value="36" label="36"/>
+                  <menuitem value="40" label="40"/>
+                  <menuitem value="44" label="44"/>
+                  <menuitem value="48" label="48"/>
+                  <menuitem value="56" label="56"/>
+                  <menuitem value="64" label="64"/>
+                  <menuitem value="72" label="72"/>
+                </menupopup>
+              </menulist>
+            </hbox>
+          </hbox>
+        </vbox>
+        <vbox id="colorsRow">
+          <hbox flex="1">
+            <button is="highlightable-button" id="advancedFonts"
+                    data-l10n-id="font-options-button"
+                    oncommand="gGeneralPane.configureFonts();"
+                    flex="1"
+                    search-l10n-ids="
+                      fonts-label-default-unnamed.label,
+                      fonts-dialog-title,
+                      fonts-language-legend.value,
+                      fonts-proportional-label.value,
+                      font-language-group-latin.label,
+                      font-language-group-japanese.label,
+                      font-language-group-trad-chinese.label,
+                      font-language-group-simpl-chinese.label,
+                      font-language-group-trad-chinese-hk.label,
+                      font-language-group-korean.label,
+                      font-language-group-cyrillic.label,
+                      font-language-group-el.label,
+                      font-language-group-other.label,
+                      font-language-group-thai.label,
+                      font-language-group-hebrew.label,
+                      font-language-group-arabic.label,
+                      font-language-group-devanagari.label,
+                      font-language-group-tamil.label,
+                      font-language-group-armenian.label,
+                      font-language-group-bengali.label,
+                      font-language-group-canadian.label,
+                      font-language-group-ethiopic.label,
+                      font-language-group-georgian.label,
+                      font-language-group-gujarati.label,
+                      font-language-group-gurmukhi.label,
+                      font-language-group-khmer.label,
+                      font-language-group-malayalam.label,
+                      font-language-group-math.label,
+                      font-language-group-odia.label,
+                      font-language-group-telugu.label,
+                      font-language-group-kannada.label,
+                      font-language-group-sinhala.label,
+                      font-language-group-tibetan.label,
+                      default-font-serif.label,
+                      default-font-sans-serif.label,
+                      font-size-label.value,
+                      font-size-monospace-label.value,
+                      font-serif-label.value,
+                      font-sans-serif-label.value,
+                      font-monospace-label.value,
+                      font-min-size-label.value,
+                      min-size-none.label,
+                      font-control-legend,
+                      use-document-fonts-checkbox.label,
+                      use-fixed-width-plain-checkbox.label,
+                      text-encoding-legend,
+                      text-encoding-description,
+                      font-outgoing-email-label.value,
+                      font-incoming-email-label.value,
+                      default-font-reply-checkbox.label"/>
+          </hbox>
+          <hbox flex="1">
+            <button is="highlightable-button" id="colors"
+                    data-l10n-id="color-options-button"
+                    oncommand="gGeneralPane.configureColors();"
+                    flex="1"
+                    search-l10n-ids="
+                      colors-dialog-window2.title,
+                      colors-dialog-legend,
+                      text-color-label.value,
+                      background-color-label.value,
+                      use-system-colors.label,
+                      colors-link-legend,
+                      link-color-label.value,
+                      visited-link-color-label.value,
+                      underline-link-checkbox.label,
+                      override-color-label.value,
+                      override-color-always.label,
+                      override-color-auto.label,
+                      override-color-never.label"/>
+          </hbox>
+        </vbox>
+      </hbox>
+      <hbox>
+        <html:legend data-l10n-id="display-width-legend"></html:legend>
+      </hbox>
+      <hbox>
+        <checkbox id="displayGlyph"
+                  preference="mail.display_glyph"
+                  data-l10n-id="convert-emoticons-label"/>
+        <spacer flex="1"/>
+      </hbox>
+
+      <separator class="thin"/>
+
+      <label control="displayText" data-l10n-id="display-text-label"/>
+      <hbox id="displayText" class="indent" align="center" role="group">
+        <label data-l10n-id="style-label" control="mailQuotedStyle"/>
+        <hbox>
+          <menulist id="mailQuotedStyle" preference="mail.quoted_style">
+            <menupopup>
+              <menuitem value="0" data-l10n-id="regular-style-item"/>
+              <menuitem value="1" data-l10n-id="bold-style-item"/>
+              <menuitem value="2" data-l10n-id="italic-style-item"/>
+              <menuitem value="3" data-l10n-id="bold-italic-style-item"/>
+            </menupopup>
+          </menulist>
+        </hbox>
+        <label data-l10n-id="size-label" control="mailQuotedSize"/>
+        <hbox>
+          <menulist id="mailQuotedSize" preference="mail.quoted_size">
+            <menupopup>
+              <menuitem value="0" data-l10n-id="regular-size-item"/>
+              <menuitem value="1" data-l10n-id="bigger-size-item"/>
+              <menuitem value="2" data-l10n-id="smaller-size-item"/>
+            </menupopup>
+          </menulist>
+        </hbox>
+        <label data-l10n-id="quoted-text-color" control="citationmenu"/>
+        <html:input type="color" id="citationmenu" preference="mail.citation_color"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <!-- Date and time formatting -->
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <html:legend data-l10n-id="datetime-formatting-legend"></html:legend>
+      <radiogroup id="formatLocale" align="start"
+                  preference="intl.regional_prefs.use_os_locales"
+                  orient="vertical">
+        <radio id="appLocale"
+               value="false"/>
+               <!-- label and accesskey will be set dynamically -->
+        <radio id="rsLocale"
+               value="true"/>
+               <!-- label and accesskey will be set dynamically -->
+      </radiogroup>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset id="messengerLanguagesBox" data-category="paneGeneral" hidden="hidden">
+      <html:legend data-l10n-id="language-selector-legend"></html:legend>
+        <vbox align="start">
+        <description flex="1"
+                     controls="chooseMessengerLanguage"
+                     data-l10n-id="choose-messenger-language-description"/>
+        <hbox>
+          <hbox>
+            <menulist id="primaryMessengerLocale"
+                      oncommand="gGeneralPane.onPrimaryMessengerLanguageMenuChange(event)">
+              <menupopup/>
+            </menulist>
+          </hbox>
+          <hbox>
+            <button is="highlightable-button" id="manageMessengerLanguagesButton"
+                    class="accessory-button"
+                    data-l10n-id="manage-messenger-languages-button"
+                    oncommand="gGeneralPane.showMessengerLanguagesSubDialog({search: false})"
+                    search-l10n-ids="
+                      languages-customize-moveup.label,
+                      languages-customize-movedown.label,
+                      languages-customize-remove.label,
+                      languages-customize-select-language.placeholder,
+                      languages-customize-add.label,
+                      messenger-languages-window2.title,
+                      messenger-languages-description,
+                      messenger-languages-search,
+                      messenger-languages-searching.label,
+                      messenger-languages-downloading.label,
+                      messenger-languages-select-language.label,
+                      messenger-languages-installed-label,
+                      messenger-languages-available-label,
+                      messenger-languages-error"/>
+          </hbox>
+        </hbox>
+      </vbox>
+      <hbox id="confirmMessengerLanguage"
+            class="message-bar"
+            align="center"
+            hidden="true">
+        <html:img class="message-bar-icon"
+                  src="chrome://global/skin/icons/info.svg" alt="" />
+        <vbox class="message-bar-content-container" align="stretch" flex="1"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <!-- Scrolling -->
+    <html:div data-category="paneGeneral">
+    <html:fieldset id="scrollingGroup" data-category="paneGeneral">
+      <html:legend data-l10n-id="scrolling-legend"></html:legend>
+      <hbox>
+        <checkbox id="useAutoScroll"
+                  data-l10n-id="autoscroll-label"
+                  preference="general.autoScroll"/>
+        <spacer flex="1"/>
+      </hbox>
+      <hbox>
+        <checkbox id="useSmoothScrolling"
+                  data-l10n-id="smooth-scrolling-label"
+                  preference="general.smoothScroll"/>
+        <spacer flex="1"/>
+      </hbox>
+#ifdef MOZ_WIDGET_GTK
+      <hbox>
+        <checkbox id="useOverlayScrollbars"
+                  data-l10n-id="browsing-gtk-use-non-overlay-scrollbars"
+                  preference="widget.gtk.overlay-scrollbars.enabled"/>
+        <spacer flex="1"/>
+      </hbox>
+#endif
+    </html:fieldset>
+    </html:div>
+
+    <hbox id="incomingMailCategory"
+          class="subcategory"
+          data-category="paneGeneral">
+      <html:h1 data-l10n-id="general-incoming-mail-header"/>
+    </hbox>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <html:legend data-l10n-id="new-message-arrival"></html:legend>
+#if defined(XP_MACOSX) || defined(XP_WIN)
+      <hbox align="center">
+        <description flex="1" data-l10n-id="change-dock-icon"/>
+        <hbox>
+          <button is="highlightable-button" id="dockOptions"
+                  oncommand="gGeneralPane.configureDockOptions();"
+                  data-l10n-id="app-icon-options"
+                  search-l10n-ids="
+                    dock-options-window-dialog2.title,
+                    bounce-system-dock-icon.label,
+                    dock-icon-legend,
+                    dock-icon-show-label.value,
+                    count-unread-messages-radio.label,
+                    count-new-messages-radio.label,
+                    notification-settings-info2"/>
+        </hbox>
+      </hbox>
+#endif
+#ifdef XP_MACOSX
+      <description class="bold" data-l10n-id="notification-settings2"/>
+#else
+      <hbox align="center">
+        <checkbox id="newMailNotificationAlert"
+                  data-l10n-id="animated-alert-label"
+                  preference="mail.biff.show_alert"/>
+        <spacer flex="1"/>
+        <hbox>
+          <button is="highlightable-button" id="customizeMailAlert"
+                  oncommand="gGeneralPane.customizeMailAlert();"
+                  data-l10n-id="customize-alert-label"
+                  search-l10n-ids="
+                    notifications-dialog-window.title,
+                    customize-alert-description,
+                    preview-text-checkbox.label,
+                    subject-checkbox.label,
+                    sender-checkbox.label,
+                    open-time-label-before.value,
+                    open-time-label-after.value"/>
+        </hbox>
+      </hbox>
+      <hbox align="center" class="indent">
+        <checkbox id="useSystemNotificationAlert"
+                  data-l10n-id="biff-use-system-alert"
+                  preference="mail.biff.use_system_alert"/>
+      </hbox>
+#ifdef XP_WIN
+      <vbox>
+        <checkbox id="newMailNotificationTrayIcon"
+                  preference="mail.biff.show_tray_icon"
+                  data-l10n-id="tray-icon-unread-label"/>
+        <description class="indent tip-caption"
+                     flex="1"
+                     data-l10n-id="tray-icon-unread-description"/>
+      </vbox>
+#endif
+#endif
+
+      <hbox align="center">
+        <checkbox id="newMailNotification"
+                  preference="mail.biff.play_sound"
+                  data-l10n-id="mail-play-sound-label"
+                  oncommand="gGeneralPane.updatePlaySound();"/>
+        <spacer flex="1"/>
+        <button is="highlightable-button" id="playSound"
+                data-l10n-id="mail-play-button"
+                oncommand="gGeneralPane.previewSound();"/>
+      </hbox>
+
+#ifndef XP_MACOSX
+      <radiogroup id="soundType"
+                  class="indent"
+                  preference="mail.biff.play_sound.type"
+                  orient="vertical"
+                  oncommand="gGeneralPane.updatePlaySound();"
+                  aria-labelledby="newMailNotification">
+        <hbox>
+          <radio id="system"
+                 value="0"
+                 data-l10n-id="mail-system-sound-label"/>
+          <spacer flex="1"/>
+        </hbox>
+        <hbox>
+          <radio id="custom"
+                 value="1"
+                 data-l10n-id="mail-custom-sound-label"/>
+          <spacer flex="1"/>
+        </hbox>
+      </radiogroup>
+#endif
+      <hbox align="center" class="input-container">
+        <html:input id="soundUrlLocation"
+                    type="text"
+                    class="input-filefield indent"
+                    readonly="readonly"
+                    preference="mail.biff.play_sound.url"
+                    preference-editable="true"
+                    aria-labelledby="custom"/>
+        <button is="highlightable-button" id="browseForSound"
+                data-l10n-id="mail-browse-sound-button"
+                oncommand="gGeneralPane.browseForSoundFile();"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <hbox id="filesAttachmentCategory"
+          class="subcategory"
+          data-category="paneGeneral">
+      <html:h1 data-l10n-id="general-files-and-attachment-header"/>
+    </hbox>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <search-textbox id="filter"
+                      data-l10n-id="search-handler-table"
+                      data-l10n-attrs="placeholder"
+                      aria-controls="handlersTable"
+                      oncommand="gGeneralPane._rebuildView();"/>
+      <separator class="thin"/>
+      <html:div id="handlersView"
+                preference="pref.downloads.disable_button.edit_actions">
+        <html:table id="handlersTable">
+          <html:thead>
+            <html:tr>
+              <html:th scope="col"
+                       sort-type="type">
+                <html:button class="handlerHeaderButton">
+                  <html:span class="handlerHeader"
+                             data-l10n-id="type-column-header">
+                  </html:span>
+                  <html:img class="handlerSortHeaderIcon"
+                            alt=""/>
+                </html:button>
+              </html:th>
+              <html:th scope="col"
+                       sort-type="action">
+                <html:button class="handlerHeaderButton">
+                  <html:span class="handlerHeader"
+                             data-l10n-id="action-column-header">
+                  </html:span>
+                  <html:img class="handlerSortHeaderIcon"
+                            alt=""/>
+                </html:button>
+              </html:th>
+            </html:tr>
+          </html:thead>
+          <html:tbody>
+          </html:tbody>
+        </html:table>
+      </html:div>
+
+      <separator class="thin"/>
+
+      <vbox align="start">
+        <radiogroup id="saveWhere" flex="1"
+                    preference="browser.download.useDownloadDir">
+          <hbox id="saveToRow" align="center" class="input-container">
+            <radio id="saveTo" value="true"
+                   data-l10n-id="save-to-label"
+                   aria-labelledby="saveTo downloadFolder"/>
+            <html:input id="downloadFolder"
+                        class="input-filefield"
+                        type="text"
+                        readonly="readonly"
+                        aria-labelledby="saveTo"/>
+            <button is="highlightable-button" id="chooseFolder"
+                    oncommand="gDownloadDirSection.chooseFolder();"
+                    data-l10n-id="choose-folder-label"/>
+          </hbox>
+          <hbox>
+            <radio id="alwaysAsk"
+                   value="false"
+                   data-l10n-id="always-ask-label"/>
+          </hbox>
+        </radiogroup>
+      </vbox>
+    </html:fieldset>
+    </html:div>
+
+    <hbox id="tagsCategory"
+          class="subcategory"
+          data-category="paneGeneral">
+      <html:h1 data-l10n-id="general-tags-header"/>
+    </hbox>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <label control="tagList" data-l10n-id="display-tags-text"/>
+      <hbox>
+        <richlistbox id="tagList"
+                     flex="1"
+                     ondblclick="gGeneralPane.editTag();"
+                     onselect="gGeneralPane.onSelectTag();"/>
+        <vbox id="tagButtons">
+          <hbox>
+            <button is="highlightable-button" id="newTagButton"
+                    data-l10n-id="new-tag-button"
+                    oncommand="gGeneralPane.addTag();"
+                    search-l10n-ids="
+                      tag-dialog-window.title,
+                      tag-name-label.value"/>
+          </hbox>
+          <hbox>
+            <button is="highlightable-button" id="editTagButton"
+                    disabled="true"
+                    data-l10n-id="edit-tag-button"
+                    oncommand="gGeneralPane.editTag();"
+                    search-l10n-ids="
+                      tag-dialog-window.title,
+                      tag-name-label.value"/>
+          </hbox>
+          <button is="highlightable-button" id="removeTagButton"
+                  disabled="true"
+                  data-l10n-id="delete-tag-button"
+                  oncommand="gGeneralPane.removeTag();"/>
+        </vbox>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <hbox id="readingAndDisplayCategory"
+          class="subcategory"
+          data-category="paneGeneral">
+      <html:h1 data-l10n-id="general-reading-and-display-header"/>
+    </hbox>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <vbox>
+        <hbox>
+          <checkbox id="viewAttachmentsInline"
+                    data-l10n-id="view-attachments-inline"
+                    preference="mail.inline_attachments"/>
+        </hbox>
+
+        <hbox>
+          <checkbox id="automaticallyMarkAsRead"
+                    preference="mailnews.mark_message_read.auto"
+                    data-l10n-id="auto-mark-as-read"/>
+        </hbox>
+
+        <radiogroup id="markAsReadAutoPreferences" orient="vertical"
+                    class="indent"
+                    align="start"
+                    preference="mailnews.mark_message_read.delay">
+          <radio id="mark_read_immediately"
+                 data-l10n-id="mark-read-no-delay"
+                 value="false"/>
+          <hbox align="center">
+            <radio id="markAsReadAfterDelay" value="true"
+                   data-l10n-id="mark-read-delay"/>
+            <html:input id="markAsReadDelay" type="number" class="size3"
+                        min="1" max="2147483"
+                        preference="mailnews.mark_message_read.delay.interval"
+                        aria-labelledby="markAsReadAfterDelay markAsReadDelay secondsLabel"/>
+            <label id="secondsLabel" data-l10n-id="seconds-label"/>
+          </hbox>
+        </radiogroup>
+      </vbox>
+
+      <separator/>
+
+      <vbox>
+        <hbox>
+          <label data-l10n-id="open-msg-label"
+                 control="mailOpenMessageBehavior"/>
+        </hbox>
+        <hbox>
+          <radiogroup id="mailOpenMessageBehavior" class="indent"
+                      preference="mail.openMessageBehavior"
+                      orient="horizontal">
+            <radio id="newTab" value="2" data-l10n-id="open-msg-tab"/>
+            <radio id="newWindow" value="0" data-l10n-id="open-msg-window"/>
+            <radio id="existingWindow" value="1"
+                   data-l10n-id="open-msg-ex-window"/>
+          </radiogroup>
+        </hbox>
+        <hbox>
+          <checkbox id="closeMsgOnMoveOrDelete"
+                    data-l10n-id="close-move-delete"
+                    preference="mail.close_message_window.on_delete"/>
+        </hbox>
+      </vbox>
+
+      <separator/>
+
+      <hbox>
+        <label data-l10n-id="display-name-label"/>
+        </hbox>
+        <hbox>
+        <checkbox id="showCondensedAddresses"
+                  data-l10n-id="condensed-addresses-label"
+                  preference="mail.showCondensedAddresses"/>
+      </hbox>
+
+      <separator class="thin"/>
+
+      <hbox align="center">
+        <description flex="1" data-l10n-id="return-receipts-description"/>
+        <hbox>
+          <button is="highlightable-button" id="showReturnReceipts"
+                  data-l10n-id="return-receipts-button"
+                  oncommand="gGeneralPane.showReturnReceipts();"
+                  search-l10n-ids="
+                    receipts-dialog-window.title,
+                    return-receipt-checkbox-control.label,
+                    receipt-arrive-label,
+                    receipt-leave-radio-control.label,
+                    receipt-move-radio-control.label,
+                    receipt-request-label,
+                    receipt-return-never-radio-control.label,
+                    receipt-return-some-radio-control.label,
+                    receipt-not-to-cc-label.value,
+                    receipt-send-never-label.label,
+                    receipt-send-always-label.label,
+                    receipt-send-ask-label.label,
+                    sender-outside-domain-label.value,
+                    other-cases-text-label.value"/>
+        </hbox>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+#ifdef MOZ_UPDATER
+    <hbox id="updatesCategory"
+          class="subcategory"
+          data-category="paneGeneral">
+      <html:h1 data-l10n-id="general-updates-header"/>
+    </hbox>
+
+    <!-- Update -->
+    <html:div data-category="paneGeneral">
+    <html:fieldset id="updateApp" data-category="paneGeneral">
+      <html:legend data-l10n-id="update-app-legend"></html:legend>
+      <hbox align="center">
+        <vbox>
+          <description>
+            <label id="version"/>
+            <label is="text-link" id="releasenotes" hidden="true" data-l10n-id="release-notes-link"></label>
+          </description>
+          <description id="distribution" class="text-blurb" hidden="true"/>
+          <description id="distributionId" class="text-blurb" hidden="true"/>
+        </vbox>
+        <spacer flex="1"/>
+        <vbox>
+          <hbox>
+            <button is="highlightable-button" id="showUpdateHistory"
+                    data-l10n-id="update-history-button"
+                    preference="app.update.disable_button.showUpdateHistory"
+                    oncommand="gGeneralPane.showUpdates();"
+                    search-l10n-ids="
+                      history-title,
+                      history-intro,
+                      close-button-label.buttonlabelcancel,
+                      close-button-label.title,
+                      no-updates-label,
+                      name-header,
+                      date-header,
+                      type-header,
+                      state-header"/>
+          </hbox>
+        </vbox>
+      </hbox>
+      <hbox id="updateBox">
+        <deck id="updateDeck" orient="vertical" flex="1">
+          <html:div id="checkForUpdates" class="update-deck-container">
+            <html:button id="checkForUpdatesButton"
+                         data-l10n-id="update-check-for-updates-button"
+                         onclick="gAppUpdater.checkForUpdates();">
+            </html:button>
+          </html:div>
+          <html:div id="downloadAndInstall" class="update-deck-container">
+            <html:button id="downloadAndInstallButton"
+                         onclick="gAppUpdater.startDownload();">
+            </html:button>
+          </html:div>
+          <html:div id="apply" class="update-deck-container">
+            <html:button id="updateButton"
+                         data-l10n-id="update-update-button"
+                         onclick="gAppUpdater.buttonRestartAfterDownload();">
+            </html:button>
+          </html:div>
+          <html:div id="checkingForUpdates" class="update-deck-container">
+            <html:img class="update-throbber" alt="" />
+            <html:span data-l10n-id="update-checking-for-updates"></html:span>
+            <!-- Button is only used for presentation in reference to the actual
+               - button that triggered this action, which would now be
+               - invisible -->
+            <html:button data-l10n-id="update-check-for-updates-button"
+                         disabled="true">
+            </html:button>
+          </html:div>
+          <html:div id="downloading" class="update-deck-container"
+                    data-l10n-id="update-downloading">
+            <html:img class="update-throbber" data-l10n-name="icon"></html:img>
+            <!-- Group within a single span to center align with icon. -->
+            <html:span id="downloadStatus" data-l10n-name="download-status"></html:span>
+          </html:div>
+          <html:div id="applying" class="update-deck-container">
+            <html:img class="update-throbber"/>
+            <html:span data-l10n-id="update-applying"></html:span>
+          </html:div>
+          <html:div id="downloadFailed" class="update-deck-container"
+                    data-l10n-id="update-failed">
+            <html:a id="failedLink" class="text-link download-link"
+                    data-l10n-name="failed-link"></html:a>
+            <html:button data-l10n-id="update-check-for-updates-button"
+                         onclick="gAppUpdater.checkForUpdates();">
+            </html:button>
+          </html:div>
+          <html:div id="policyDisabled" class="update-deck-container">
+            <html:span data-l10n-id="update-admin-disabled"></html:span>
+          </html:div>
+          <html:div id="noUpdatesFound" class="update-deck-container">
+            <html:span data-l10n-id="update-no-updates-found"></html:span>
+            <html:button data-l10n-id="update-check-for-updates-button"
+                         onclick="gAppUpdater.checkForUpdates();">
+            </html:button>
+          </html:div>
+          <html:div id="checkingFailed" class="update-deck-container">
+            <html:span data-l10n-id="aboutdialog-update-checking-failed"></html:span>
+            <html:button data-l10n-id="update-check-for-updates-button"
+                         onclick="gAppUpdater.checkForUpdates();">
+            </html:button>
+          </html:div>
+          <html:div id="otherInstanceHandlingUpdates"
+                    class="update-deck-container">
+            <html:span data-l10n-id="update-other-instance-handling-updates"></html:span>
+          </html:div>
+          <html:div id="manualUpdate" class="update-deck-container"
+                    data-l10n-id="update-manual">
+            <html:a id="manualLink" class="manualLink text-link download-link"
+                    data-l10n-name="manual-link"></html:a>
+            <html:button data-l10n-id="update-check-for-updates-button"
+                         onclick="gAppUpdater.checkForUpdates();">
+            </html:button>
+          </html:div>
+          <html:div id="unsupportedSystem" class="update-deck-container" data-l10n-id="update-unsupported">
+            <html:a id="unsupportedLink" class="text-link download-link"
+                    data-l10n-name="unsupported-link"></html:a>
+          </html:div>
+          <html:div id="restarting" class="update-deck-container">
+            <html:span class="update-throbber"></html:span>
+            <html:span data-l10n-id="update-restarting"></html:span>
+          </html:div>
+          <html:div id="internalError" class="update-deck-container"
+                    data-l10n-id="update-internal-error">
+            <html:a id="internalErrorLink" class="manualLink text-link download-link"
+                    data-l10n-name="manual-link"></html:a>
+            <html:button data-l10n-id="update-check-for-updates-button"
+                         onclick="gAppUpdater.checkForUpdates();">
+            </html:button>
+          </html:div>
+        </deck>
+      </hbox>
+      <separator/>
+      <description id="updateAllowDescription" data-l10n-id="allow-description"/>
+      <vbox id="updateSettingsContainer">
+        <radiogroup id="updateRadioGroup"
+                    align="start">
+          <radio id="autoDesktop"
+                 value="true"
+                 data-l10n-id="automatic-updates-label"/>
+          <radio id="manualDesktop"
+                 value="false"
+                 data-l10n-id="check-updates-label"/>
+        </radiogroup>
+        <description id="updateSettingCrossUserWarning"
+                     data-l10n-id="cross-user-udpate-warning"
+                     hidden="true"/>
+      </vbox>
+
+#ifdef MOZ_MAINTENANCE_SERVICE
+      <separator class="thin"/>
+      <checkbox id="useService"
+                data-l10n-id="use-service"
+                preference="app.update.service.enabled"/>
+#endif
+    </html:fieldset>
+    </html:div>
+#endif
+
+    <hbox id="networkAndDiskspaceCategory"
+          class="subcategory"
+          data-category="paneGeneral">
+      <html:h1 data-l10n-id="general-network-and-diskspace-header"/>
+    </hbox>
+
+    <!-- Networking & Disk Space -->
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <html:legend data-l10n-id="networking-legend"></html:legend>
+      <hbox align="center">
+        <description control="catProxiesButton"
+                     data-l10n-id="proxy-config-description"
+                     flex="1"/>
+        <hbox>
+          <button is="highlightable-button" id="catProxiesButton"
+                  data-l10n-id="network-settings-button"
+                  oncommand="gGeneralPane.showConnections();"
+                  search-l10n-ids="
+                    connection-dns-over-https-url-resolver,
+                    connection-dns-over-https-url-custom.label,
+                    connection-dns-over-https-custom-label,
+                    connection-proxy-legend,
+                    proxy-type-no.label,
+                    proxy-type-wpad.label,
+                    proxy-type-system.label,
+                    proxy-type-manual.label,
+                    proxy-http-label.value,
+                    http-port-label.value,
+                    proxy-http-sharing.label,
+                    proxy-https-label.value,
+                    ssl-port-label.value,
+                    proxy-socks-label.value,
+                    socks-port-label.value,
+                    proxy-socks4-label.label,
+                    proxy-socks5-label.label,
+                    proxy-type-auto.label,
+                    proxy-reload-label.label,
+                    no-proxy-label.value,
+                    no-proxy-example,
+                    connection-proxy-noproxy-localhost-desc-2,
+                    proxy-password-prompt.label,
+                    proxy-remote-dns.label,
+                    proxy-enable-doh.label"/>
+        </hbox>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <html:legend data-l10n-id="offline-legend"></html:legend>
+      <hbox align="center">
+        <description data-l10n-id="offline-settings"
+                     control="offlineSettingsButton"
+                     flex="1"/>
+        <hbox>
+          <button is="highlightable-button" id="offlineSettingsButton"
+                  data-l10n-id="offline-settings-button"
+                  oncommand="gGeneralPane.showOffline();"
+                  search-l10n-ids="
+                    offline-dialog-window.title,
+                    autodetect-online-label.label,
+                    startup-label,
+                    status-radio-remember.label,
+                    status-radio-ask.label,
+                    status-radio-always-online.label,
+                    status-radio-always-offline.label,
+                    going-online-label,
+                    going-online-auto.label,
+                    going-online-not.label,
+                    going-online-ask.label,
+                    going-offline-label,
+                    going-offline-auto.label,
+                    going-offline-not.label,
+                    going-offline-ask.label"/>
+        </hbox>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <html:legend data-l10n-id="diskspace-legend"></html:legend>
+      <hbox align="center">
+        <label id="actualDiskCacheSize" flex="1"/>
+        <button is="highlightable-button" id="clearCacheButton"
+                data-l10n-id="clear-cache-button"
+                oncommand="gGeneralPane.clearCache();"/>
+      </hbox>
+      <hbox>
+        <checkbox id="clearCacheOnShutdown"
+                  preference="privacy.clearOnShutdown.cache"
+                  data-l10n-id="clear-cache-shutdown-label"/>
+      </hbox>
+      <hbox>
+        <checkbox id="allowSmartSize"
+                  preference="browser.cache.disk.smart_size.enabled"
+                  data-l10n-id="smart-cache-label"/>
+      </hbox>
+      <hbox align="center" class="indent">
+        <label id="useCacheBefore" control="cacheSize"
+               data-l10n-id="use-cache-before"/>
+        <html:input id="cacheSize" type="number" class="size4" max="1024"
+                    preference="browser.cache.disk.capacity"
+                    aria-labelledby="useCacheBefore cacheSize useCacheAfter"/>
+        <label id="useCacheAfter" data-l10n-id="use-cache-after" flex="1"/>
+      </hbox>
+      <hbox align="center">
+          <checkbox id="offlineCompactFolder"
+                    data-l10n-id="offline-compact-folder"
+                    aria-labelledby="offlineCompactFolder offlineCompactFolderMin compactFolderMB"
+                    preference="mail.prompt_purge_threshhold"
+                    oncommand="gGeneralPane.updateCompactOptions();"/>
+          <html:input id="offlineCompactFolderMin" type="number" class="size4"
+                      min="1" max="2048" value="200"
+                      preference="mail.purge_threshhold_mb"
+                      aria-labelledby="offlineCompactFolder offlineCompactFolderMin compactFolderMB"/>
+          <label id="compactFolderMB" data-l10n-id="compact-folder-size" value=""/>
+      </hbox>
+      <hbox align="center" class="indent">
+        <checkbox id="offlineCompactFolderAutomatically"
+                  data-l10n-id="offline-compact-folder-automatically"
+                  preference="mail.purge.ask"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <html:legend data-l10n-id="general-indexing-label"></html:legend>
+      <vbox>
+        <hbox>
+          <checkbox id="enableGloda"
+                    preference="mailnews.database.global.indexer.enabled"
+                    data-l10n-id="enable-gloda-search-label"/>
+        </hbox>
+        <hbox align="center">
+          <label control="storeTypeMenulist" data-l10n-id="store-type-label"/>
+          <hbox>
+            <menulist id="storeTypeMenulist"
+                      oncommand="gGeneralPane.updateDefaultStore(this.selectedItem.value)">
+              <menupopup id="storeTypeMenupopup">
+                <menuitem id="mboxStore"
+                          data-l10n-id="mbox-store-label"
+                          value="@mozilla.org/msgstore/berkeleystore;1"/>
+                <menuitem id="maildirStore"
+                          data-l10n-id="maildir-store-label"
+                          value="@mozilla.org/msgstore/maildirstore;1"/>
+              </menupopup>
+            </menulist>
+          </hbox>
+        </hbox>
+        <hbox>
+          <checkbox id="allowHWAccel"
+                    preference="layers.acceleration.disabled"
+                    data-l10n-id="allow-hw-accel"/>
+        </hbox>
+      </vbox>
+      <vbox>
+      </vbox>
+    </html:fieldset>
+    </html:div>
+
+    <separator class="thin" data-category="paneGeneral"/>
+
+    <html:div data-category="paneGeneral">
+    <html:fieldset data-category="paneGeneral">
+      <hbox pack="end">
+        <hbox>
+          <button is="highlightable-button" id="configEditor"
+                  data-l10n-id="config-editor-button"
+                  oncommand="gGeneralPane.showConfigEdit();"
+                  searchkeywords="about:config"
+                  search-l10n-ids="
+                    about-config-page-title,
+                    about-config-search-input1.placeholder,
+                    about-config-show-all,
+                    about-config-pref-add-button.title,
+                    about-config-pref-toggle-button.title,
+                    about-config-pref-edit-button.title,
+                    about-config-pref-save-button.title,
+                    about-config-pref-reset-button.title,
+                    about-config-pref-delete-button.title,
+                    about-config-pref-add-type-boolean,
+                    about-config-pref-add-type-number,
+                    about-config-pref-add-type-string
+                    "/>
+        </hbox>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+  </html:template>
diff --git a/comm/mail/components/preferences/general.js b/comm/mail/components/preferences/general.js
new file mode 100644
index 0000000000..96e8aaad2d
--- /dev/null
+++ b/comm/mail/components/preferences/general.js
@@ -0,0 +1,2962 @@
+/* -*- Mode: JavaScript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * 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";
+
+/* import-globals-from ../../base/content/aboutDialog-appUpdater.js */
+/* import-globals-from ../../../../toolkit/mozapps/preferences/fontbuilder.js */
+/* import-globals-from preferences.js */
+
+// ------------------------------
+// Constants & Enumeration Values
+
+var { DownloadUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/DownloadUtils.sys.mjs"
+);
+var { XPCOMUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/XPCOMUtils.sys.mjs"
+);
+var { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+var { UpdateUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/UpdateUtils.sys.mjs"
+);
+var { TagUtils } = ChromeUtils.import("resource:///modules/TagUtils.jsm");
+
+XPCOMUtils.defineLazyServiceGetters(this, {
+  gHandlerService: [
+    "@mozilla.org/uriloader/handler-service;1",
+    "nsIHandlerService",
+  ],
+  gMIMEService: ["@mozilla.org/mime;1", "nsIMIMEService"],
+});
+
+XPCOMUtils.defineLazyGetter(this, "gIsPackagedApp", () => {
+  return Services.sysinfo.getProperty("isPackagedApp");
+});
+
+const TYPE_PDF = "application/pdf";
+
+const PREF_PDFJS_DISABLED = "pdfjs.disabled";
+
+const AUTO_UPDATE_CHANGED_TOPIC = "auto-update-config-change";
+
+Preferences.addAll([
+  { id: "mail.pane_config.dynamic", type: "int" },
+  { id: "mailnews.reuse_message_window", type: "bool" },
+  { id: "mailnews.start_page.enabled", type: "bool" },
+  { id: "mailnews.start_page.url", type: "string" },
+  { id: "mail.biff.show_tray_icon", type: "bool" },
+  { id: "mail.biff.play_sound", type: "bool" },
+  { id: "mail.biff.play_sound.type", type: "int" },
+  { id: "mail.biff.play_sound.url", type: "string" },
+  { id: "mail.biff.use_system_alert", type: "bool" },
+  { id: "general.autoScroll", type: "bool" },
+  { id: "general.smoothScroll", type: "bool" },
+  { id: "widget.gtk.overlay-scrollbars.enabled", type: "bool", inverted: true },
+  { id: "mail.fixed_width_messages", type: "bool" },
+  { id: "mail.inline_attachments", type: "bool" },
+  { id: "mail.quoted_style", type: "int" },
+  { id: "mail.quoted_size", type: "int" },
+  { id: "mail.citation_color", type: "string" },
+  { id: "mail.display_glyph", type: "bool" },
+  { id: "font.language.group", type: "wstring" },
+  { id: "intl.regional_prefs.use_os_locales", type: "bool" },
+  { id: "mailnews.database.global.indexer.enabled", type: "bool" },
+  { id: "mailnews.labels.description.1", type: "wstring" },
+  { id: "mailnews.labels.color.1", type: "string" },
+  { id: "mailnews.labels.description.2", type: "wstring" },
+  { id: "mailnews.labels.color.2", type: "string" },
+  { id: "mailnews.labels.description.3", type: "wstring" },
+  { id: "mailnews.labels.color.3", type: "string" },
+  { id: "mailnews.labels.description.4", type: "wstring" },
+  { id: "mailnews.labels.color.4", type: "string" },
+  { id: "mailnews.labels.description.5", type: "wstring" },
+  { id: "mailnews.labels.color.5", type: "string" },
+  { id: "mail.showCondensedAddresses", type: "bool" },
+  { id: "mailnews.mark_message_read.auto", type: "bool" },
+  { id: "mailnews.mark_message_read.delay", type: "bool" },
+  { id: "mailnews.mark_message_read.delay.interval", type: "int" },
+  { id: "mail.openMessageBehavior", type: "int" },
+  { id: "mail.close_message_window.on_delete", type: "bool" },
+  { id: "mail.prompt_purge_threshhold", type: "bool" },
+  { id: "mail.purge.ask", type: "bool" },
+  { id: "mail.purge_threshhold_mb", type: "int" },
+  { id: "browser.cache.disk.capacity", type: "int" },
+  { id: "browser.cache.disk.smart_size.enabled", inverted: true, type: "bool" },
+  { id: "privacy.clearOnShutdown.cache", type: "bool" },
+  { id: "layers.acceleration.disabled", type: "bool", inverted: true },
+  { id: "searchintegration.enable", type: "bool" },
+  { id: "mail.tabs.drawInTitlebar", type: "bool" },
+  { id: "mail.tabs.autoHide", type: "bool" },
+]);
+if (AppConstants.platform == "win") {
+  Preferences.add({ id: "mail.minimizeToTray", type: "bool" });
+}
+if (AppConstants.platform != "macosx") {
+  Preferences.add({ id: "mail.biff.show_alert", type: "bool" });
+}
+
+var ICON_URL_APP = "";
+
+if (AppConstants.MOZ_WIDGET_GTK) {
+  ICON_URL_APP = "moz-icon://dummy.exe?size=16";
+} else {
+  ICON_URL_APP = "chrome://messenger/skin/preferences/application.png";
+}
+
+if (AppConstants.HAVE_SHELL_SERVICE) {
+  Preferences.addAll([
+    { id: "mail.shell.checkDefaultClient", type: "bool" },
+    { id: "pref.general.disable_button.default_mail", type: "bool" },
+  ]);
+}
+
+if (AppConstants.MOZ_UPDATER) {
+  Preferences.add({
+    id: "app.update.disable_button.showUpdateHistory",
+    type: "bool",
+  });
+  if (AppConstants.MOZ_MAINTENANCE_SERVICE) {
+    Preferences.add({ id: "app.update.service.enabled", type: "bool" });
+  }
+}
+
+var gGeneralPane = {
+  // The set of types the app knows how to handle. A map of HandlerInfoWrapper
+  // objects, indexed by type.
+  _handledTypes: new Map(),
+  // Map from a handlerInfoWrapper to the corresponding table HandlerRow.
+  _handlerRows: new Map(),
+  _handlerMenuId: 0,
+
+  // The list of types we can show, sorted by the sort column/direction.
+  // An array of HandlerInfoWrapper objects.  We build this list when we first
+  // load the data and then rebuild it when users change a pref that affects
+  // what types we can show or change the sort column/direction.
+  // Note: this isn't necessarily the list of types we *will* show; if the user
+  // provides a filter string, we'll only show the subset of types in this list
+  // that match that string.
+  _visibleTypes: [],
+
+  // Map whose keys are string descriptions and values are references to the
+  // first visible HandlerInfoWrapper that has this description. We use this
+  // to determine whether or not to annotate descriptions with their types to
+  // distinguish duplicate descriptions from each other.
+  _visibleDescriptions: new Map(),
+
+  // -----------------------------------
+  // Convenience & Performance Shortcuts
+
+  // These get defined by init().
+  _brandShortName: null,
+  _handlerTbody: null,
+  _filter: null,
+  _prefsBundle: null,
+  mPane: null,
+  mStartPageUrl: "",
+  mShellServiceWorking: false,
+  mTagListBox: null,
+  requestingLocales: null,
+
+  async init() {
+    function setEventListener(aId, aEventType, aCallback) {
+      document
+        .getElementById(aId)
+        .addEventListener(aEventType, aCallback.bind(gGeneralPane));
+    }
+
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("saveWhere"),
+      () => gDownloadDirSection.onReadUseDownloadDir()
+    );
+
+    this.mPane = document.getElementById("paneGeneral");
+    this._prefsBundle = document.getElementById("bundlePreferences");
+    this._brandShortName = document
+      .getElementById("bundleBrand")
+      .getString("brandShortName");
+    this._handlerTbody = document.querySelector("#handlersTable > tbody");
+    this._filter = document.getElementById("filter");
+
+    this._handlerSort = { type: "type", descending: false };
+    this._handlerSortHeaders = document.querySelectorAll(
+      "#handlersTable > thead th[sort-type]"
+    );
+    for (let header of this._handlerSortHeaders) {
+      let button = header.querySelector("button");
+      button.addEventListener(
+        "click",
+        this.sort.bind(this, header.getAttribute("sort-type"))
+      );
+    }
+
+    this.updateStartPage();
+    this.updatePlaySound(
+      !Preferences.get("mail.biff.play_sound").value,
+      Preferences.get("mail.biff.play_sound.url").value,
+      Preferences.get("mail.biff.play_sound.type").value
+    );
+    if (AppConstants.platform != "macosx") {
+      this.updateShowAlert();
+    }
+    this.updateWebSearch();
+
+    // Search integration -- check whether we should hide or disable integration
+    let hideSearchUI = false;
+    let disableSearchUI = false;
+    const { SearchIntegration } = ChromeUtils.import(
+      "resource:///modules/SearchIntegration.jsm"
+    );
+    if (SearchIntegration) {
+      if (SearchIntegration.osVersionTooLow) {
+        hideSearchUI = true;
+      } else if (SearchIntegration.osComponentsNotRunning) {
+        disableSearchUI = true;
+      }
+    } else {
+      hideSearchUI = true;
+    }
+
+    if (hideSearchUI) {
+      document.getElementById("searchIntegrationContainer").hidden = true;
+    } else if (disableSearchUI) {
+      let searchCheckbox = document.getElementById("searchIntegration");
+      searchCheckbox.checked = false;
+      Preferences.get("searchintegration.enable").disabled = true;
+    }
+
+    // If the shell service is not working, disable the "Check now" button
+    // and "perform check at startup" checkbox.
+    try {
+      Cc["@mozilla.org/mail/shell-service;1"].getService(Ci.nsIShellService);
+      this.mShellServiceWorking = true;
+    } catch (ex) {
+      // The elements may not exist if HAVE_SHELL_SERVICE is off.
+      if (document.getElementById("alwaysCheckDefault")) {
+        document.getElementById("alwaysCheckDefault").disabled = true;
+        document.getElementById("alwaysCheckDefault").checked = false;
+      }
+      if (document.getElementById("checkDefaultButton")) {
+        document.getElementById("checkDefaultButton").disabled = true;
+      }
+      this.mShellServiceWorking = false;
+    }
+    this._rebuildFonts();
+
+    var menulist = document.getElementById("defaultFont");
+    if (menulist.selectedIndex == -1) {
+      // Prepend menuitem with empty name and value.
+      let item = document.createXULElement("menuitem");
+      item.setAttribute("label", "");
+      item.setAttribute("value", "");
+      menulist.menupopup.insertBefore(
+        item,
+        menulist.menupopup.firstElementChild
+      );
+      menulist.selectedIndex = 0;
+    }
+
+    this.formatLocaleSetLabels();
+
+    if (Services.prefs.getBoolPref("intl.multilingual.enabled")) {
+      this.initPrimaryMessengerLanguageUI();
+    }
+
+    this.mTagListBox = document.getElementById("tagList");
+    this.buildTagList();
+    this.updateMarkAsReadOptions();
+
+    document.getElementById("citationmenu").value = Preferences.get(
+      "mail.citation_color"
+    ).value;
+
+    // By doing this in a timeout, we let the preferences dialog resize itself
+    // to an appropriate size before we add a bunch of items to the list.
+    // Otherwise, if there are many items, and the Applications prefpane
+    // is the one that gets displayed when the user first opens the dialog,
+    // the dialog might stretch too much in an attempt to fit them all in.
+    // XXX Shouldn't we perhaps just set a max-height on the richlistbox?
+    var _delayedPaneLoad = function (self) {
+      self._loadAppHandlerData();
+      self._rebuildVisibleTypes();
+      self._sortVisibleTypes();
+      self._rebuildView();
+
+      // Notify observers that the UI is now ready
+      Services.obs.notifyObservers(window, "app-handler-pane-loaded");
+    };
+    this.updateActualCacheSize();
+    this.updateCompactOptions();
+
+    // Default store type initialization.
+    let storeTypeElement = document.getElementById("storeTypeMenulist");
+    // set the menuitem to match the account
+    let defaultStoreID = Services.prefs.getCharPref(
+      "mail.serverDefaultStoreContractID"
+    );
+    let targetItem = storeTypeElement.getElementsByAttribute(
+      "value",
+      defaultStoreID
+    );
+    storeTypeElement.selectedItem = targetItem[0];
+    setTimeout(_delayedPaneLoad, 0, this);
+
+    if (AppConstants.MOZ_UPDATER) {
+      this.updateReadPrefs();
+      gAppUpdater = new appUpdater(); // eslint-disable-line no-global-assign
+      let updateDisabled =
+        Services.policies && !Services.policies.isAllowed("appUpdate");
+
+      if (gIsPackagedApp) {
+        // When we're running inside an app package, there's no point in
+        // displaying any update content here, and it would get confusing if we
+        // did, because our updater is not enabled.
+        // We can't rely on the hidden attribute for the toplevel elements,
+        // because of the pane hiding/showing code interfering.
+        document
+          .getElementById("updatesCategory")
+          .setAttribute("style", "display: none !important");
+        document
+          .getElementById("updateApp")
+          .setAttribute("style", "display: none !important");
+      } else if (updateDisabled || UpdateUtils.appUpdateAutoSettingIsLocked()) {
+        document.getElementById("updateAllowDescription").hidden = true;
+        document.getElementById("updateSettingsContainer").hidden = true;
+        if (updateDisabled && AppConstants.MOZ_MAINTENANCE_SERVICE) {
+          document.getElementById("useService").hidden = true;
+        }
+      } else {
+        // Start with no option selected since we are still reading the value
+        document.getElementById("autoDesktop").removeAttribute("selected");
+        document.getElementById("manualDesktop").removeAttribute("selected");
+        // Start reading the correct value from the disk
+        this.updateReadPrefs();
+        setEventListener(
+          "updateRadioGroup",
+          "command",
+          gGeneralPane.updateWritePrefs
+        );
+      }
+
+      let defaults = Services.prefs.getDefaultBranch(null);
+      let distroId = defaults.getCharPref("distribution.id", "");
+      if (distroId) {
+        let distroVersion = defaults.getCharPref("distribution.version", "");
+
+        let distroIdField = document.getElementById("distributionId");
+        distroIdField.value = distroId + " - " + distroVersion;
+        distroIdField.style.display = "block";
+
+        let distroAbout = defaults.getStringPref("distribution.about", "");
+        if (distroAbout) {
+          let distroField = document.getElementById("distribution");
+          distroField.value = distroAbout;
+          distroField.style.display = "block";
+        }
+      }
+
+      if (AppConstants.platform == "win") {
+        // On Windows, the Application Update setting is an installation-
+        // specific preference, not a profile-specific one. Show a warning to
+        // inform users of this.
+        let updateContainer = document.getElementById(
+          "updateSettingsContainer"
+        );
+        updateContainer.classList.add("updateSettingCrossUserWarningContainer");
+        document.getElementById("updateSettingCrossUserWarning").hidden = false;
+      }
+
+      if (AppConstants.MOZ_MAINTENANCE_SERVICE) {
+        // Check to see if the maintenance service is installed.
+        // If it isn't installed, don't show the preference at all.
+        let installed;
+        try {
+          let wrk = Cc["@mozilla.org/windows-registry-key;1"].createInstance(
+            Ci.nsIWindowsRegKey
+          );
+          wrk.open(
+            wrk.ROOT_KEY_LOCAL_MACHINE,
+            "SOFTWARE\\Mozilla\\MaintenanceService",
+            wrk.ACCESS_READ | wrk.WOW64_64
+          );
+          installed = wrk.readIntValue("Installed");
+          wrk.close();
+        } catch (e) {}
+        if (installed != 1) {
+          document.getElementById("useService").hidden = true;
+        }
+      }
+
+      let version = AppConstants.MOZ_APP_VERSION_DISPLAY;
+
+      // Include the build ID and display warning if this is an "a#" (nightly) build
+      if (/a\d+$/.test(version)) {
+        let buildID = Services.appinfo.appBuildID;
+        let year = buildID.slice(0, 4);
+        let month = buildID.slice(4, 6);
+        let day = buildID.slice(6, 8);
+        version += ` (${year}-${month}-${day})`;
+      }
+
+      // Append "(32-bit)" or "(64-bit)" build architecture to the version number:
+      let bundle = Services.strings.createBundle(
+        "chrome://messenger/locale/messenger.properties"
+      );
+      let archResource = Services.appinfo.is64Bit
+        ? "aboutDialog.architecture.sixtyFourBit"
+        : "aboutDialog.architecture.thirtyTwoBit";
+      let arch = bundle.GetStringFromName(archResource);
+      version += ` (${arch})`;
+
+      document.l10n.setAttributes(
+        document.getElementById("version"),
+        "update-app-version",
+        { version }
+      );
+
+      if (!AppConstants.NIGHTLY_BUILD) {
+        // Show a release notes link if we have a URL.
+        let relNotesLink = document.getElementById("releasenotes");
+        let relNotesPrefType = Services.prefs.getPrefType(
+          "app.releaseNotesURL"
+        );
+        if (relNotesPrefType != Services.prefs.PREF_INVALID) {
+          let relNotesURL = Services.urlFormatter.formatURLPref(
+            "app.releaseNotesURL"
+          );
+          if (relNotesURL != "about:blank") {
+            relNotesLink.href = relNotesURL;
+            relNotesLink.hidden = false;
+          }
+        }
+      }
+      // Initialize Application section.
+
+      // Listen for window unload so we can remove our preference observers.
+      window.addEventListener("unload", this);
+
+      Services.obs.addObserver(this, AUTO_UPDATE_CHANGED_TOPIC);
+      Services.prefs.addObserver("mailnews.tags.", this);
+    }
+
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("allowSmartSize"),
+      () => this.readSmartSizeEnabled()
+    );
+
+    let element = document.getElementById("cacheSize");
+    Preferences.addSyncFromPrefListener(element, () => this.readCacheSize());
+    Preferences.addSyncToPrefListener(element, () => this.writeCacheSize());
+    Preferences.addSyncFromPrefListener(menulist, () =>
+      this.readFontSelection()
+    );
+    Preferences.addSyncFromPrefListener(
+      document.getElementById("soundUrlLocation"),
+      () => this.readSoundLocation()
+    );
+
+    if (!Services.policies.isAllowed("about:config")) {
+      document.getElementById("configEditor").disabled = true;
+    }
+  },
+
+  /**
+   * Restores the default start page as the user's start page
+   */
+  restoreDefaultStartPage() {
+    var startPage = Preferences.get("mailnews.start_page.url");
+    startPage.value = startPage.defaultValue;
+  },
+
+  /**
+   * Returns a formatted url corresponding to the value of mailnews.start_page.url
+   * Stores the original value of mailnews.start_page.url
+   */
+  readStartPageUrl() {
+    var pref = Preferences.get("mailnews.start_page.url");
+    this.mStartPageUrl = pref.value;
+    return Services.urlFormatter.formatURL(this.mStartPageUrl);
+  },
+
+  /**
+   * Returns the value of the mailnews start page url represented by the UI.
+   * If the url matches the formatted version of our stored value, then
+   * return the unformatted url.
+   */
+  writeStartPageUrl() {
+    var startPage = document.getElementById("mailnewsStartPageUrl");
+    return Services.urlFormatter.formatURL(this.mStartPageUrl) ==
+      startPage.value
+      ? this.mStartPageUrl
+      : startPage.value;
+  },
+
+  customizeMailAlert() {
+    gSubDialog.open(
+      "chrome://messenger/content/preferences/notifications.xhtml",
+      { features: "resizable=no" }
+    );
+  },
+
+  configureDockOptions() {
+    gSubDialog.open(
+      "chrome://messenger/content/preferences/dockoptions.xhtml",
+      { features: "resizable=no" }
+    );
+  },
+
+  convertURLToLocalFile(aFileURL) {
+    // convert the file url into a nsIFile
+    if (aFileURL) {
+      return Services.io
+        .getProtocolHandler("file")
+        .QueryInterface(Ci.nsIFileProtocolHandler)
+        .getFileFromURLSpec(aFileURL);
+    }
+    return null;
+  },
+
+  readSoundLocation() {
+    var soundUrlLocation = document.getElementById("soundUrlLocation");
+    soundUrlLocation.value = Preferences.get("mail.biff.play_sound.url").value;
+    if (soundUrlLocation.value) {
+      soundUrlLocation.label = this.convertURLToLocalFile(
+        soundUrlLocation.value
+      ).leafName;
+      soundUrlLocation.style.backgroundImage =
+        "url(moz-icon://" + soundUrlLocation.label + "?size=16)";
+    }
+  },
+
+  previewSound() {
+    let sound = Cc["@mozilla.org/sound;1"].createInstance(Ci.nsISound);
+
+    let soundLocation;
+    // soundType radio-group isn't used for macOS so it is not in the XUL file
+    // for the platform.
+    soundLocation =
+      AppConstants.platform == "macosx" ||
+      document.getElementById("soundType").value == 1
+        ? document.getElementById("soundUrlLocation").value
+        : "";
+
+    if (!soundLocation.includes("file://")) {
+      // User has not set any custom sound file to be played
+      sound.playEventSound(Ci.nsISound.EVENT_NEW_MAIL_RECEIVED);
+    } else {
+      // User has set a custom audio file to be played along the alert.
+      sound.play(Services.io.newURI(soundLocation));
+    }
+  },
+
+  browseForSoundFile() {
+    var fp = Cc["@mozilla.org/filepicker;1"].createInstance(Ci.nsIFilePicker);
+
+    // if we already have a sound file, then use the path for that sound file
+    // as the initial path in the dialog.
+    var localFile = this.convertURLToLocalFile(
+      document.getElementById("soundUrlLocation").value
+    );
+    if (localFile) {
+      fp.displayDirectory = localFile.parent;
+    }
+
+    // XXX todo, persist the last sound directory and pass it in
+    fp.init(
+      window,
+      document
+        .getElementById("bundlePreferences")
+        .getString("soundFilePickerTitle"),
+      Ci.nsIFilePicker.modeOpen
+    );
+    fp.appendFilters(Ci.nsIFilePicker.filterAudio);
+    fp.appendFilters(Ci.nsIFilePicker.filterAll);
+
+    fp.open(rv => {
+      if (rv != Ci.nsIFilePicker.returnOK || !fp.file) {
+        return;
+      }
+      // convert the nsIFile into a nsIFile url
+      Preferences.get("mail.biff.play_sound.url").value = fp.fileURL.spec;
+      this.readSoundLocation(); // XXX We shouldn't have to be doing this by hand
+      this.updatePlaySound();
+    });
+  },
+
+  updatePlaySound(soundsDisabled, soundUrlLocation, soundType) {
+    // Update the sound type radio buttons based on the state of the
+    // play sound checkbox.
+    if (soundsDisabled === undefined) {
+      soundsDisabled = !document.getElementById("newMailNotification").checked;
+      soundUrlLocation = document.getElementById("soundUrlLocation").value;
+    }
+
+    // The UI is different on OS X as the user can only choose between letting
+    // the system play a default sound or setting a custom one. Therefore,
+    // "soundTypeEl" does not exist on OS X.
+    if (AppConstants.platform != "macosx") {
+      var soundTypeEl = document.getElementById("soundType");
+      if (soundType === undefined) {
+        soundType = soundTypeEl.value;
+      }
+
+      soundTypeEl.disabled = soundsDisabled;
+      document.getElementById("soundUrlLocation").disabled =
+        soundsDisabled || soundType != 1;
+      document.getElementById("browseForSound").disabled =
+        soundsDisabled || soundType != 1;
+      document.getElementById("playSound").disabled =
+        soundsDisabled || (!soundUrlLocation && soundType != 0);
+    } else {
+      // On OS X, if there is no selected custom sound then default one will
+      // be played. We keep consistency by disabling the "Play sound" checkbox
+      // if the user hasn't selected a custom sound file yet.
+      document.getElementById("newMailNotification").disabled =
+        !soundUrlLocation;
+      document.getElementById("playSound").disabled = !soundUrlLocation;
+      // The sound type radiogroup is hidden, but we have to keep the
+      // play_sound.type pref set appropriately.
+      Preferences.get("mail.biff.play_sound.type").value =
+        !soundsDisabled && soundUrlLocation ? 1 : 0;
+    }
+  },
+
+  updateStartPage() {
+    document.getElementById("mailnewsStartPageUrl").disabled = !Preferences.get(
+      "mailnews.start_page.enabled"
+    ).value;
+    document.getElementById("browseForStartPageUrl").disabled =
+      !Preferences.get("mailnews.start_page.enabled").value;
+  },
+
+  updateShowAlert() {
+    // The button does not exist on all platforms.
+    let customizeAlertButton = document.getElementById("customizeMailAlert");
+    if (customizeAlertButton) {
+      customizeAlertButton.disabled = !Preferences.get("mail.biff.show_alert")
+        .value;
+    }
+    // The checkmark does not exist on all platforms.
+    let systemNotification = document.getElementById(
+      "useSystemNotificationAlert"
+    );
+    if (systemNotification) {
+      systemNotification.disabled = !Preferences.get("mail.biff.show_alert")
+        .value;
+    }
+  },
+
+  updateWebSearch() {
+    let self = this;
+    Services.search.init().then(async () => {
+      let defaultEngine = await Services.search.getDefault();
+      let engineList = document.getElementById("defaultWebSearch");
+      for (let engine of await Services.search.getVisibleEngines()) {
+        let item = engineList.appendItem(engine.name);
+        item.engine = engine;
+        item.className = "menuitem-iconic";
+        item.setAttribute(
+          "image",
+          engine.iconURI
+            ? engine.iconURI.spec
+            : "resource://gre-resources/broken-image.png"
+        );
+        if (engine == defaultEngine) {
+          engineList.selectedItem = item;
+        }
+      }
+      self.defaultEngines = await Services.search.getAppProvidedEngines();
+      self.updateRemoveButton();
+
+      engineList.addEventListener("command", async () => {
+        await Services.search.setDefault(
+          engineList.selectedItem.engine,
+          Ci.nsISearchService.CHANGE_REASON_USER
+        );
+        self.updateRemoveButton();
+      });
+    });
+  },
+
+  // Caches the default engines so we only retrieve them once.
+  defaultEngines: null,
+
+  async updateRemoveButton() {
+    let engineList = document.getElementById("defaultWebSearch");
+    let removeButton = document.getElementById("removeSearchEngine");
+    if (this.defaultEngines.includes(await Services.search.getDefault())) {
+      // Don't allow deletion of a default engine (saves us having a 'restore' button).
+      removeButton.disabled = true;
+    } else {
+      // Don't allow removal of last engine. This shouldn't happen since there should
+      // always be default engines.
+      removeButton.disabled = engineList.itemCount <= 1;
+    }
+  },
+
+  /**
+   * Look up OpenSearch Description URL.
+   *
+   * @param url - the url to use as basis for discovery
+   */
+  async lookupOpenSearch(url) {
+    let response = await fetch(url);
+    if (!response.ok) {
+      throw new Error(`Bad response for url=${url}`);
+    }
+    let contentType = response.headers.get("Content-Type")?.toLowerCase();
+    if (
+      contentType == "application/opensearchdescription+xml" ||
+      contentType == "application/xml" ||
+      contentType == "text/xml"
+    ) {
+      return url;
+    }
+    let doc = new DOMParser().parseFromString(
+      await response.text(),
+      "text/html"
+    );
+    let auto = doc.querySelector(
+      "link[rel='search'][type='application/opensearchdescription+xml']"
+    );
+    if (!auto) {
+      throw new Error(`No provider discovered for url=${url}`);
+    }
+    return /^https?:/.test(auto.href)
+      ? auto.href
+      : new URL(url).origin + auto.href;
+  },
+
+  async addSearchEngine() {
+    let input = { value: "https://" };
+    let [title, text] = await document.l10n.formatValues([
+      "add-opensearch-provider-title",
+      "add-opensearch-provider-text",
+    ]);
+    let result = Services.prompt.prompt(window, title, text, input, null, {
+      value: false,
+    });
+    input.value = input.value.trim();
+    if (!result || !input.value || input.value == "https://") {
+      return;
+    }
+    let url = input.value;
+    let engine;
+    try {
+      url = await this.lookupOpenSearch(url);
+      engine = await Services.search.addOpenSearchEngine(url, null);
+    } catch (reason) {
+      let [title, text] = await document.l10n.formatValues([
+        { id: "adding-opensearch-provider-failed-title" },
+        { id: "adding-opensearch-provider-failed-text", args: { url } },
+      ]);
+      Services.prompt.alert(window, title, text);
+      return;
+    }
+    // Wait a bit, so the engine iconURI has time to be fetched.
+    // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+    await new Promise(r => setTimeout(r, 500));
+
+    // Add new engine to the list, make the added engine the default.
+    let engineList = document.getElementById("defaultWebSearch");
+    let item = engineList.appendItem(engine.name);
+    item.engine = engine;
+    item.className = "menuitem-iconic";
+    item.setAttribute(
+      "image",
+      engine.iconURI
+        ? engine.iconURI.spec
+        : "resource://gre-resources/broken-image.png"
+    );
+    engineList.selectedIndex =
+      engineList.firstElementChild.childElementCount - 1;
+    await Services.search.setDefault(
+      engineList.selectedItem.engine,
+      Ci.nsISearchService.CHANGE_REASON_USER
+    );
+    this.updateRemoveButton();
+  },
+
+  async removeSearchEngine() {
+    // Deletes the current engine. Firefox does a better job since it
+    // shows all the engines in the list. But better than nothing.
+    let defaultEngine = await Services.search.getDefault();
+    let engineList = document.getElementById("defaultWebSearch");
+    for (let i = 0; i < engineList.itemCount; i++) {
+      let item = engineList.getItemAtIndex(i);
+      if (item.engine == defaultEngine) {
+        await Services.search.removeEngine(item.engine);
+        item.remove();
+        engineList.selectedIndex = 0;
+        await Services.search.setDefault(
+          engineList.selectedItem.engine,
+          Ci.nsISearchService.CHANGE_REASON_USER
+        );
+        this.updateRemoveButton();
+        break;
+      }
+    }
+  },
+
+  /**
+   * Checks whether Thunderbird is currently registered with the operating
+   * system as the default app for mail, rss and news.  If Thunderbird is not
+   * currently the default app, the user is given the option of making it the
+   * default for each type; otherwise, the user is informed that Thunderbird is
+   * already the default.
+   */
+  checkDefaultNow(aAppType) {
+    if (!this.mShellServiceWorking) {
+      return;
+    }
+
+    // otherwise, bring up the default client dialog
+    gSubDialog.open(
+      "chrome://messenger/content/systemIntegrationDialog.xhtml",
+      { features: "resizable=no" },
+      "calledFromPrefs"
+    );
+  },
+
+  // FONTS
+
+  /**
+   * Populates the default font list in UI.
+   */
+  _rebuildFonts() {
+    var langGroupPref = Preferences.get("font.language.group");
+    var isSerif =
+      gGeneralPane._readDefaultFontTypeForLanguage(langGroupPref.value) ==
+      "serif";
+    gGeneralPane._selectDefaultLanguageGroup(langGroupPref.value, isSerif);
+  },
+
+  /**
+   * Select the default language group.
+   */
+  _selectDefaultLanguageGroupPromise: Promise.resolve(),
+
+  _selectDefaultLanguageGroup(aLanguageGroup, aIsSerif) {
+    this._selectDefaultLanguageGroupPromise = (async () => {
+      // Avoid overlapping language group selections by awaiting the resolution
+      // of the previous one.  We do this because this function is re-entrant,
+      // as inserting <preference> elements into the DOM sometimes triggers a call
+      // back into this function.  And since this function is also asynchronous,
+      // that call can enter this function before the previous run has completed,
+      // which would corrupt the font menulists.  Awaiting the previous call's
+      // resolution avoids that fate.
+      await this._selectDefaultLanguageGroupPromise;
+
+      const kFontNameFmtSerif = "font.name.serif.%LANG%";
+      const kFontNameFmtSansSerif = "font.name.sans-serif.%LANG%";
+      const kFontNameListFmtSerif = "font.name-list.serif.%LANG%";
+      const kFontNameListFmtSansSerif = "font.name-list.sans-serif.%LANG%";
+      const kFontSizeFmtVariable = "font.size.variable.%LANG%";
+
+      // Make sure font.name-list is created before font.name so that it's
+      // available at the time readFontSelection below is called.
+      var prefs = [
+        {
+          format: aIsSerif ? kFontNameListFmtSerif : kFontNameListFmtSansSerif,
+          type: "unichar",
+          element: null,
+          fonttype: aIsSerif ? "serif" : "sans-serif",
+        },
+        {
+          format: aIsSerif ? kFontNameFmtSerif : kFontNameFmtSansSerif,
+          type: "fontname",
+          element: "defaultFont",
+          fonttype: aIsSerif ? "serif" : "sans-serif",
+        },
+        {
+          format: kFontSizeFmtVariable,
+          type: "int",
+          element: "defaultFontSize",
+          fonttype: null,
+        },
+      ];
+
+      for (var i = 0; i < prefs.length; ++i) {
+        var preference = Preferences.get(
+          prefs[i].format.replace(/%LANG%/, aLanguageGroup)
+        );
+        if (!preference) {
+          preference = Preferences.add({
+            id: prefs[i].format.replace(/%LANG%/, aLanguageGroup),
+            type: prefs[i].type,
+          });
+        }
+
+        if (!prefs[i].element) {
+          continue;
+        }
+
+        var element = document.getElementById(prefs[i].element);
+        if (element) {
+          if (prefs[i].fonttype) {
+            await FontBuilder.buildFontList(
+              aLanguageGroup,
+              prefs[i].fonttype,
+              element
+            );
+          }
+
+          element.setAttribute("preference", preference.id);
+
+          preference.setElementValue(element);
+        }
+      }
+    })().catch(console.error);
+  },
+
+  /**
+   * Displays the fonts dialog, where web page font names and sizes can be
+   * configured.
+   */
+  configureFonts() {
+    gSubDialog.open("chrome://messenger/content/preferences/fonts.xhtml", {
+      features: "resizable=no",
+    });
+  },
+
+  /**
+   * Displays the colors dialog, where default web page/link/etc. colors can be
+   * configured.
+   */
+  configureColors() {
+    gSubDialog.open("chrome://messenger/content/preferences/colors.xhtml", {
+      features: "resizable=no",
+    });
+  },
+
+  /**
+   * Returns the type of the current default font for the language denoted by
+   * aLanguageGroup.
+   */
+  _readDefaultFontTypeForLanguage(aLanguageGroup) {
+    const kDefaultFontType = "font.default.%LANG%";
+    var defaultFontTypePref = kDefaultFontType.replace(
+      /%LANG%/,
+      aLanguageGroup
+    );
+    var preference = Preferences.get(defaultFontTypePref);
+    if (!preference) {
+      Preferences.add({
+        id: defaultFontTypePref,
+        type: "string",
+        name: defaultFontTypePref,
+      }).on("change", gGeneralPane._rebuildFonts);
+    }
+
+    // We should return preference.value here, but we can't wait for the binding to load,
+    // or things get really messy. Fortunately this will give the same answer.
+    return Services.prefs.getCharPref(defaultFontTypePref);
+  },
+
+  /**
+   * Determine the appropriate value to select for defaultFont, for the
+   * following cases:
+   * - there is no setting
+   * - the font selected by the user is no longer present (e.g. deleted from
+   *   fonts folder)
+   */
+  readFontSelection() {
+    let element = document.getElementById("defaultFont");
+    let preference = Preferences.get(element.getAttribute("preference"));
+    if (preference.value) {
+      let fontItem = element.querySelector(
+        '[value="' + preference.value + '"]'
+      );
+
+      // There is a setting that actually is in the list. Respect it.
+      if (fontItem) {
+        return undefined;
+      }
+    }
+
+    let defaultValue =
+      element.firstElementChild.firstElementChild.getAttribute("value");
+    let languagePref = Preferences.get("font.language.group");
+    let defaultType = this._readDefaultFontTypeForLanguage(languagePref.value);
+    let listPref = Preferences.get(
+      "font.name-list." + defaultType + "." + languagePref.value
+    );
+    if (!listPref) {
+      return defaultValue;
+    }
+
+    let fontNames = listPref.value.split(",");
+
+    for (let fontName of fontNames) {
+      let fontItem = element.querySelector('[value="' + fontName.trim() + '"]');
+      if (fontItem) {
+        return fontItem.getAttribute("value");
+      }
+    }
+    return defaultValue;
+  },
+
+  async formatLocaleSetLabels() {
+    // HACK: calling getLocaleDisplayNames may fail the first time due to
+    // synchronous loading of the .ftl files. If we load the files and wait
+    // for a known value asynchronously, no such failure will happen.
+    await new Localization([
+      "toolkit/intl/languageNames.ftl",
+      "toolkit/intl/regionNames.ftl",
+    ]).formatValue("language-name-en");
+
+    const osprefs = Cc["@mozilla.org/intl/ospreferences;1"].getService(
+      Ci.mozIOSPreferences
+    );
+    let appLocale = Services.locale.appLocalesAsBCP47[0];
+    let rsLocale = osprefs.regionalPrefsLocales[0];
+    let names = Services.intl.getLocaleDisplayNames(undefined, [
+      appLocale,
+      rsLocale,
+    ]);
+    let appLocaleRadio = document.getElementById("appLocale");
+    let rsLocaleRadio = document.getElementById("rsLocale");
+    let appLocaleLabel = this._prefsBundle.getFormattedString(
+      "appLocale.label",
+      [names[0]]
+    );
+    let rsLocaleLabel = this._prefsBundle.getFormattedString("rsLocale.label", [
+      names[1],
+    ]);
+    appLocaleRadio.setAttribute("label", appLocaleLabel);
+    rsLocaleRadio.setAttribute("label", rsLocaleLabel);
+    appLocaleRadio.accessKey = this._prefsBundle.getString(
+      "appLocale.accesskey"
+    );
+    rsLocaleRadio.accessKey = this._prefsBundle.getString("rsLocale.accesskey");
+  },
+
+  // Load the preferences string bundle for other locales with fallbacks.
+  getBundleForLocales(newLocales) {
+    let locales = Array.from(
+      new Set([
+        ...newLocales,
+        ...Services.locale.requestedLocales,
+        Services.locale.lastFallbackLocale,
+      ])
+    );
+    return new Localization(
+      ["messenger/preferences/preferences.ftl", "branding/brand.ftl"],
+      false,
+      undefined,
+      locales
+    );
+  },
+
+  initPrimaryMessengerLanguageUI() {
+    gGeneralPane.updatePrimaryMessengerLanguageUI(
+      Services.locale.requestedLocale
+    );
+  },
+
+  /**
+   * Update the available list of locales and select the locale that the user
+   * is "selecting". This could be the currently requested locale or a locale
+   * that the user would like to switch to after confirmation.
+   *
+   * @param {string} selected - The selected BCP 47 locale.
+   */
+  async updatePrimaryMessengerLanguageUI(selected) {
+    // HACK: calling getLocaleDisplayNames may fail the first time due to
+    // synchronous loading of the .ftl files. If we load the files and wait
+    // for a known value asynchronously, no such failure will happen.
+    await new Localization([
+      "toolkit/intl/languageNames.ftl",
+      "toolkit/intl/regionNames.ftl",
+    ]).formatValue("language-name-en");
+
+    let available = await getAvailableLocales();
+    let localeNames = Services.intl.getLocaleDisplayNames(
+      undefined,
+      available,
+      { preferNative: true }
+    );
+    let locales = available.map((code, i) => ({ code, name: localeNames[i] }));
+    locales.sort((a, b) => a.name > b.name);
+
+    let fragment = document.createDocumentFragment();
+    for (let { code, name } of locales) {
+      let menuitem = document.createXULElement("menuitem");
+      menuitem.setAttribute("value", code);
+      menuitem.setAttribute("label", name);
+      fragment.appendChild(menuitem);
+    }
+
+    // Add an option to search for more languages if downloading is supported.
+    if (Services.prefs.getBoolPref("intl.multilingual.downloadEnabled")) {
+      let menuitem = document.createXULElement("menuitem");
+      menuitem.id = "primaryMessengerLocaleSearch";
+      menuitem.setAttribute(
+        "label",
+        await document.l10n.formatValue("messenger-languages-search")
+      );
+      menuitem.setAttribute("value", "search");
+      menuitem.addEventListener("command", () => {
+        gGeneralPane.showMessengerLanguagesSubDialog({ search: true });
+      });
+      fragment.appendChild(menuitem);
+    }
+
+    let menulist = document.getElementById("primaryMessengerLocale");
+    let menupopup = menulist.querySelector("menupopup");
+    menupopup.textContent = "";
+    menupopup.appendChild(fragment);
+    menulist.value = selected;
+
+    document.getElementById("messengerLanguagesBox").hidden = false;
+  },
+
+  /**
+   * Open the messenger languages sub dialog in either the normal mode, or search mode.
+   * The search mode is only available from the menu to change the primary browser
+   * language.
+   *
+   * @param {{ search: boolean }}
+   */
+  showMessengerLanguagesSubDialog({ search }) {
+    let opts = {
+      selectedLocalesForRestart: gGeneralPane.selectedLocalesForRestart,
+      search,
+    };
+    gSubDialog.open(
+      "chrome://messenger/content/preferences/messengerLanguages.xhtml",
+      { closingCallback: this.messengerLanguagesClosed },
+      opts
+    );
+  },
+
+  /**
+   * Returns the assumed script directionality for known Firefox locales. This is
+   * somewhat crude, but should work until Bug 1750781 lands.
+   *
+   * TODO (Bug 1750781) - This should use Intl.LocaleInfo once it is standardized (see
+   * Bug 1693576), rather than maintaining a hardcoded list of RTL locales.
+   *
+   * @param {string} locale
+   * @returns {"ltr" | "rtl"}
+   */
+  getLocaleDirection(locale) {
+    if (
+      locale == "ar" ||
+      locale == "ckb" ||
+      locale == "fa" ||
+      locale == "he" ||
+      locale == "ur"
+    ) {
+      return "rtl";
+    }
+    return "ltr";
+  },
+
+  /**
+   * Determine the transition strategy for switching the locale based on prefs
+   * and the switched locales.
+   *
+   * @param {Array<string>} newLocales - List of BCP 47 locale identifiers.
+   * @returns {"locales-match" | "requires-restart" | "live-reload"}
+   */
+  getLanguageSwitchTransitionType(newLocales) {
+    const { appLocalesAsBCP47 } = Services.locale;
+    if (appLocalesAsBCP47.join(",") === newLocales.join(",")) {
+      // The selected locales match, the order matters.
+      return "locales-match";
+    }
+
+    if (Services.prefs.getBoolPref("intl.multilingual.liveReload")) {
+      if (
+        gGeneralPane.getLocaleDirection(newLocales[0]) !==
+          gGeneralPane.getLocaleDirection(appLocalesAsBCP47[0]) &&
+        !Services.prefs.getBoolPref("intl.multilingual.liveReloadBidirectional")
+      ) {
+        // Bug 1750852: The directionality of the text changed, which requires a restart
+        // until the quality of the switch can be improved.
+        return "requires-restart";
+      }
+
+      return "live-reload";
+    }
+
+    return "requires-restart";
+  },
+
+  /* Show or hide the confirm change message bar based on the updated ordering. */
+  messengerLanguagesClosed() {
+    // When the subdialog is closed, settings are stored on gMessengerLanguagesDialog.
+    // The next time the dialog is opened, a new gMessengerLanguagesDialog is created.
+    let { selected } = this.gMessengerLanguagesDialog;
+
+    if (!selected) {
+      // No locales were selected. Cancel the operation.
+      return;
+    }
+
+    switch (gGeneralPane.getLanguageSwitchTransitionType(selected)) {
+      case "requires-restart":
+        gGeneralPane.showConfirmLanguageChangeMessageBar(selected);
+        gGeneralPane.updatePrimaryMessengerLanguageUI(selected[0]);
+        break;
+      case "live-reload":
+        Services.locale.requestedLocales = selected;
+
+        gGeneralPane.updatePrimaryMessengerLanguageUI(
+          Services.locale.appLocaleAsBCP47
+        );
+        gGeneralPane.hideConfirmLanguageChangeMessageBar();
+        break;
+      case "locales-match":
+        // They matched, so we can reset the UI.
+        gGeneralPane.updatePrimaryMessengerLanguageUI(
+          Services.locale.appLocaleAsBCP47
+        );
+        gGeneralPane.hideConfirmLanguageChangeMessageBar();
+        break;
+      default:
+        throw new Error("Unhandled transition type.");
+    }
+  },
+
+  /* Show the confirmation message bar to allow a restart into the new locales. */
+  async showConfirmLanguageChangeMessageBar(locales) {
+    let messageBar = document.getElementById("confirmMessengerLanguage");
+
+    // Get the bundle for the new locale.
+    let newBundle = this.getBundleForLocales(locales);
+
+    // Find the messages and labels.
+    let messages = await Promise.all(
+      [newBundle, document.l10n].map(async bundle =>
+        bundle.formatValue("confirm-messenger-language-change-description")
+      )
+    );
+    let buttonLabels = await Promise.all(
+      [newBundle, document.l10n].map(async bundle =>
+        bundle.formatValue("confirm-messenger-language-change-button")
+      )
+    );
+
+    // If both the message and label are the same, just include one row.
+    if (messages[0] == messages[1] && buttonLabels[0] == buttonLabels[1]) {
+      messages.pop();
+      buttonLabels.pop();
+    }
+
+    let contentContainer = messageBar.querySelector(
+      ".message-bar-content-container"
+    );
+    contentContainer.textContent = "";
+
+    for (let i = 0; i < messages.length; i++) {
+      let messageContainer = document.createXULElement("hbox");
+      messageContainer.classList.add("message-bar-content");
+      messageContainer.setAttribute("flex", "1");
+      messageContainer.setAttribute("align", "center");
+
+      let description = document.createXULElement("description");
+      description.classList.add("message-bar-description");
+
+      if (i == 0 && gGeneralPane.getLocaleDirection(locales[0]) === "rtl") {
+        description.classList.add("rtl-locale");
+      }
+
+      description.setAttribute("flex", "1");
+      description.textContent = messages[i];
+      messageContainer.appendChild(description);
+
+      let button = document.createXULElement("button");
+      button.addEventListener("command", gGeneralPane.confirmLanguageChange);
+      button.classList.add("message-bar-button");
+      button.setAttribute("locales", locales.join(","));
+      button.setAttribute("label", buttonLabels[i]);
+      messageContainer.appendChild(button);
+
+      contentContainer.appendChild(messageContainer);
+    }
+
+    messageBar.hidden = false;
+    this.selectedLocalesForRestart = locales;
+  },
+
+  hideConfirmLanguageChangeMessageBar() {
+    let messageBar = document.getElementById("confirmMessengerLanguage");
+    messageBar.hidden = true;
+    let contentContainer = messageBar.querySelector(
+      ".message-bar-content-container"
+    );
+    contentContainer.textContent = "";
+    this.requestingLocales = null;
+  },
+
+  /* Confirm the locale change and restart the Thunderbird in the new locale. */
+  confirmLanguageChange(event) {
+    let localesString = (event.target.getAttribute("locales") || "").trim();
+    if (!localesString || localesString.length == 0) {
+      return;
+    }
+    let locales = localesString.split(",");
+    Services.locale.requestedLocales = locales;
+
+    // Restart with the new locale.
+    let cancelQuit = Cc["@mozilla.org/supports-PRBool;1"].createInstance(
+      Ci.nsISupportsPRBool
+    );
+    Services.obs.notifyObservers(
+      cancelQuit,
+      "quit-application-requested",
+      "restart"
+    );
+    if (!cancelQuit.data) {
+      Services.startup.quit(
+        Services.startup.eAttemptQuit | Services.startup.eRestart
+      );
+    }
+  },
+
+  /* Show or hide the confirm change message bar based on the new locale. */
+  onPrimaryMessengerLanguageMenuChange(event) {
+    let locale = event.target.value;
+
+    if (locale == "search") {
+      return;
+    } else if (locale == Services.locale.appLocaleAsBCP47) {
+      this.hideConfirmLanguageChangeMessageBar();
+      return;
+    }
+
+    let newLocales = Array.from(
+      new Set([locale, ...Services.locale.requestedLocales]).values()
+    );
+
+    switch (gGeneralPane.getLanguageSwitchTransitionType(newLocales)) {
+      case "requires-restart":
+        // Prepare to change the locales, as they were different.
+        gGeneralPane.showConfirmLanguageChangeMessageBar(newLocales);
+        gGeneralPane.updatePrimaryMessengerLanguageUI(newLocales[0]);
+        break;
+      case "live-reload":
+        Services.locale.requestedLocales = newLocales;
+        gGeneralPane.updatePrimaryMessengerLanguageUI(
+          Services.locale.appLocaleAsBCP47
+        );
+        gGeneralPane.hideConfirmLanguageChangeMessageBar();
+        break;
+      case "locales-match":
+        // They matched, so we can reset the UI.
+        gGeneralPane.updatePrimaryMessengerLanguageUI(
+          Services.locale.appLocaleAsBCP47
+        );
+        gGeneralPane.hideConfirmLanguageChangeMessageBar();
+        break;
+      default:
+        throw new Error("Unhandled transition type.");
+    }
+  },
+
+  // appends the tag to the tag list box
+  appendTagItem(aTagName, aKey, aColor) {
+    let item = this.mTagListBox.appendItem(aTagName, aKey);
+    item.style.color = aColor;
+    return item;
+  },
+
+  buildTagList() {
+    let tagArray = MailServices.tags.getAllTags();
+    for (let i = 0; i < tagArray.length; ++i) {
+      let taginfo = tagArray[i];
+      this.appendTagItem(taginfo.tag, taginfo.key, taginfo.color);
+    }
+  },
+
+  removeTag() {
+    var index = this.mTagListBox.selectedIndex;
+    if (index >= 0) {
+      var itemToRemove = this.mTagListBox.getItemAtIndex(index);
+      MailServices.tags.deleteKey(itemToRemove.getAttribute("value"));
+    }
+  },
+
+  /**
+   * Open the edit tag dialog
+   */
+  editTag() {
+    var index = this.mTagListBox.selectedIndex;
+    if (index >= 0) {
+      var tagElToEdit = this.mTagListBox.getItemAtIndex(index);
+      var args = {
+        result: "",
+        keyToEdit: tagElToEdit.getAttribute("value"),
+      };
+      gSubDialog.open(
+        "chrome://messenger/content/preferences/tagDialog.xhtml",
+        { features: "resizable=no" },
+        args
+      );
+    }
+  },
+
+  addTag() {
+    var args = { result: "", okCallback: addTagCallback };
+    gSubDialog.open(
+      "chrome://messenger/content/preferences/tagDialog.xhtml",
+      { features: "resizable=no" },
+      args
+    );
+  },
+
+  onSelectTag() {
+    let btnEdit = document.getElementById("editTagButton");
+    let listBox = document.getElementById("tagList");
+
+    if (listBox.selectedCount > 0) {
+      btnEdit.disabled = false;
+    } else {
+      btnEdit.disabled = true;
+    }
+
+    document.getElementById("removeTagButton").disabled = btnEdit.disabled;
+  },
+
+  /**
+   * Enable/disable the options of automatic marking as read depending on the
+   * state of the automatic marking feature.
+   */
+  updateMarkAsReadOptions() {
+    let enableRadioGroup = Preferences.get(
+      "mailnews.mark_message_read.auto"
+    ).value;
+    let autoMarkAsPref = Preferences.get("mailnews.mark_message_read.delay");
+    let autoMarkDisabled = !enableRadioGroup || autoMarkAsPref.locked;
+    document.getElementById("markAsReadAutoPreferences").disabled =
+      autoMarkDisabled;
+    document.getElementById("secondsLabel").disabled = autoMarkDisabled;
+    gGeneralPane.updateMarkAsReadTextbox();
+  },
+
+  /**
+   * Automatically enable/disable delay textbox depending on state of the
+   * Mark As Read On Delay feature.
+   */
+  updateMarkAsReadTextbox() {
+    let radioGroupEnabled = Preferences.get(
+      "mailnews.mark_message_read.auto"
+    ).value;
+    let textBoxEnabled = Preferences.get(
+      "mailnews.mark_message_read.delay"
+    ).value;
+    let intervalPref = Preferences.get(
+      "mailnews.mark_message_read.delay.interval"
+    );
+
+    let delayTextbox = document.getElementById("markAsReadDelay");
+    delayTextbox.disabled =
+      !radioGroupEnabled || !textBoxEnabled || intervalPref.locked;
+    if (document.activeElement.id == "markAsReadAutoPreferences") {
+      delayTextbox.focus();
+    }
+  },
+
+  /**
+   * Display the return receipts configuration dialog.
+   */
+  showReturnReceipts() {
+    gSubDialog.open("chrome://messenger/content/preferences/receipts.xhtml", {
+      features: "resizable=no",
+    });
+  },
+
+  /**
+   * Show the about:config page in a tab.
+   */
+  showConfigEdit() {
+    // If the about:config tab is already open, switch to the tab.
+    let mainWin = Services.wm.getMostRecentWindow("mail:3pane");
+    let tabmail = mainWin.document.getElementById("tabmail");
+    for (let tabInfo of tabmail.tabInfo) {
+      let tab = tabmail.getTabForBrowser(tabInfo.browser);
+      if (tab?.urlbar?.value == "about:config") {
+        tabmail.switchToTab(tabInfo);
+        return;
+      }
+    }
+    // Wasn't open already. Open in a new tab.
+    tabmail.openTab("contentTab", { url: "about:config" });
+  },
+
+  /**
+   * Display the the connection settings dialog.
+   */
+  showConnections() {
+    gSubDialog.open("chrome://messenger/content/preferences/connection.xhtml");
+  },
+
+  /**
+   * Display the the offline settings dialog.
+   */
+  showOffline() {
+    gSubDialog.open("chrome://messenger/content/preferences/offline.xhtml", {
+      features: "resizable=no",
+    });
+  },
+
+  /*
+   * browser.cache.disk.capacity
+   * - the size of the browser cache in KB
+   */
+
+  // Retrieves the amount of space currently used by disk cache
+  updateActualCacheSize() {
+    let actualSizeLabel = document.getElementById("actualDiskCacheSize");
+    let prefStrBundle = document.getElementById("bundlePreferences");
+
+    // Needs to root the observer since cache service keeps only a weak reference.
+    this.observer = {
+      onNetworkCacheDiskConsumption(consumption) {
+        let size = DownloadUtils.convertByteUnits(consumption);
+        // The XBL binding for the string bundle may have been destroyed if
+        // the page was closed before this callback was executed.
+        if (!prefStrBundle.getFormattedString) {
+          return;
+        }
+        actualSizeLabel.value = prefStrBundle.getFormattedString(
+          "actualDiskCacheSize",
+          size
+        );
+      },
+
+      QueryInterface: ChromeUtils.generateQI([
+        "nsICacheStorageConsumptionObserver",
+        "nsISupportsWeakReference",
+      ]),
+    };
+
+    actualSizeLabel.value = prefStrBundle.getString(
+      "actualDiskCacheSizeCalculated"
+    );
+
+    try {
+      Services.cache2.asyncGetDiskConsumption(this.observer);
+    } catch (e) {}
+  },
+
+  updateCacheSizeUI(smartSizeEnabled) {
+    document.getElementById("useCacheBefore").disabled = smartSizeEnabled;
+    document.getElementById("cacheSize").disabled = smartSizeEnabled;
+    document.getElementById("useCacheAfter").disabled = smartSizeEnabled;
+  },
+
+  readSmartSizeEnabled() {
+    // The smart_size.enabled preference element is inverted="true", so its
+    // value is the opposite of the actual pref value
+    var disabled = Preferences.get(
+      "browser.cache.disk.smart_size.enabled"
+    ).value;
+    this.updateCacheSizeUI(!disabled);
+  },
+
+  /**
+   * Converts the cache size from units of KB to units of MB and returns that
+   * value.
+   */
+  readCacheSize() {
+    var preference = Preferences.get("browser.cache.disk.capacity");
+    return preference.value / 1024;
+  },
+
+  /**
+   * Converts the cache size as specified in UI (in MB) to KB and returns that
+   * value.
+   */
+  writeCacheSize() {
+    var cacheSize = document.getElementById("cacheSize");
+    var intValue = parseInt(cacheSize.value, 10);
+    return isNaN(intValue) ? 0 : intValue * 1024;
+  },
+
+  /**
+   * Clears the cache.
+   */
+  clearCache() {
+    try {
+      Services.cache2.clear();
+    } catch (ex) {}
+    this.updateActualCacheSize();
+  },
+
+  updateCompactOptions() {
+    let disabled =
+      !Preferences.get("mail.prompt_purge_threshhold").value ||
+      Preferences.get("mail.purge_threshhold_mb").locked;
+
+    document.getElementById("offlineCompactFolderMin").disabled = disabled;
+    document.getElementById("offlineCompactFolderAutomatically").disabled =
+      disabled;
+  },
+
+  /**
+   * Set the default store contract ID.
+   */
+  updateDefaultStore(storeID) {
+    Services.prefs.setCharPref("mail.serverDefaultStoreContractID", storeID);
+  },
+
+  /**
+   * When the user toggles the layers.acceleration.disabled pref,
+   * sync its new value to the gfx.direct2d.disabled pref too.
+   * Note that layers.acceleration.disabled is inverted.
+   */
+  updateHardwareAcceleration() {
+    if (AppConstants.platform == "win") {
+      let preference = Preferences.get("layers.acceleration.disabled");
+      Services.prefs.setBoolPref("gfx.direct2d.disabled", !preference.value);
+    }
+  },
+
+  /**
+   * Selects the correct item in the update radio group
+   */
+  async updateReadPrefs() {
+    if (
+      AppConstants.MOZ_UPDATER &&
+      (!Services.policies || Services.policies.isAllowed("appUpdate")) &&
+      !gIsPackagedApp
+    ) {
+      let radiogroup = document.getElementById("updateRadioGroup");
+      radiogroup.disabled = true;
+      try {
+        let enabled = await UpdateUtils.getAppUpdateAutoEnabled();
+        radiogroup.value = enabled;
+        radiogroup.disabled = false;
+      } catch (error) {
+        console.error(error);
+      }
+    }
+  },
+
+  /**
+   * Writes the value of the update radio group to the disk
+   */
+  async updateWritePrefs() {
+    if (
+      AppConstants.MOZ_UPDATER &&
+      (!Services.policies || Services.policies.isAllowed("appUpdate")) &&
+      !gIsPackagedApp
+    ) {
+      let radiogroup = document.getElementById("updateRadioGroup");
+      let updateAutoValue = radiogroup.value == "true";
+      radiogroup.disabled = true;
+      try {
+        await UpdateUtils.setAppUpdateAutoEnabled(updateAutoValue);
+        radiogroup.disabled = false;
+      } catch (error) {
+        console.error(error);
+        await this.updateReadPrefs();
+        await this.reportUpdatePrefWriteError();
+        return;
+      }
+
+      // If the value was changed to false the user should be given the option
+      // to discard an update if there is one.
+      if (!updateAutoValue) {
+        await this.checkUpdateInProgress();
+      }
+    }
+  },
+
+  async reportUpdatePrefWriteError() {
+    let [title, message] = await document.l10n.formatValues([
+      { id: "update-setting-write-failure-title" },
+      {
+        id: "update-setting-write-failure-message",
+        args: { path: UpdateUtils.configFilePath },
+      },
+    ]);
+
+    // Set up the Ok Button
+    let buttonFlags =
+      Services.prompt.BUTTON_POS_0 * Services.prompt.BUTTON_TITLE_OK;
+    Services.prompt.confirmEx(
+      window,
+      title,
+      message,
+      buttonFlags,
+      null,
+      null,
+      null,
+      null,
+      {}
+    );
+  },
+
+  async checkUpdateInProgress() {
+    let um = Cc["@mozilla.org/updates/update-manager;1"].getService(
+      Ci.nsIUpdateManager
+    );
+    if (!um.readyUpdate && !um.downloadingUpdate) {
+      return;
+    }
+
+    let [title, message, okButton, cancelButton] =
+      await document.l10n.formatValues([
+        { id: "update-in-progress-title" },
+        { id: "update-in-progress-message" },
+        { id: "update-in-progress-ok-button" },
+        { id: "update-in-progress-cancel-button" },
+      ]);
+
+    // Continue is the cancel button which is BUTTON_POS_1 and is set as the
+    // default so pressing escape or using a platform standard method of closing
+    // the UI will not discard the update.
+    let buttonFlags =
+      Ci.nsIPrompt.BUTTON_TITLE_IS_STRING * Ci.nsIPrompt.BUTTON_POS_0 +
+      Ci.nsIPrompt.BUTTON_TITLE_IS_STRING * Ci.nsIPrompt.BUTTON_POS_1 +
+      Ci.nsIPrompt.BUTTON_POS_1_DEFAULT;
+
+    let rv = Services.prompt.confirmEx(
+      window,
+      title,
+      message,
+      buttonFlags,
+      okButton,
+      cancelButton,
+      null,
+      null,
+      {}
+    );
+    if (rv != 1) {
+      let aus = Cc["@mozilla.org/updates/update-service;1"].getService(
+        Ci.nsIApplicationUpdateService
+      );
+      aus.stopDownload();
+      um.cleanupReadyUpdate();
+      um.cleanupDownloadingUpdate();
+    }
+  },
+
+  showUpdates() {
+    gSubDialog.open("chrome://mozapps/content/update/history.xhtml");
+  },
+
+  _loadAppHandlerData() {
+    this._loadInternalHandlers();
+    this._loadApplicationHandlers();
+  },
+
+  _loadInternalHandlers() {
+    const internalHandlers = [new PDFHandlerInfoWrapper()];
+    for (const internalHandler of internalHandlers) {
+      if (internalHandler.enabled) {
+        this._handledTypes.set(internalHandler.type, internalHandler);
+      }
+    }
+  },
+
+  /**
+   * Load the set of handlers defined by the application datastore.
+   */
+  _loadApplicationHandlers() {
+    for (let wrappedHandlerInfo of gHandlerService.enumerate()) {
+      let type = wrappedHandlerInfo.type;
+
+      let handlerInfoWrapper;
+      if (this._handledTypes.has(type)) {
+        handlerInfoWrapper = this._handledTypes.get(type);
+      } else {
+        handlerInfoWrapper = new HandlerInfoWrapper(type, wrappedHandlerInfo);
+        this._handledTypes.set(type, handlerInfoWrapper);
+      }
+    }
+  },
+
+  // -----------------
+  // View Construction
+
+  _rebuildVisibleTypes() {
+    // Reset the list of visible types and the visible type description.
+    this._visibleTypes.length = 0;
+    this._visibleDescriptions.clear();
+
+    for (let handlerInfo of this._handledTypes.values()) {
+      // We couldn't find any reason to exclude the type, so include it.
+      this._visibleTypes.push(handlerInfo);
+
+      let otherHandlerInfo = this._visibleDescriptions.get(
+        handlerInfo.description
+      );
+      if (!otherHandlerInfo) {
+        // This is the first type with this description that we encountered
+        // while rebuilding the _visibleTypes array this time. Make sure the
+        // flag is reset so we won't add the type to the description.
+        handlerInfo.disambiguateDescription = false;
+        this._visibleDescriptions.set(handlerInfo.description, handlerInfo);
+      } else {
+        // There is at least another type with this description. Make sure we
+        // add the type to the description on both HandlerInfoWrapper objects.
+        handlerInfo.disambiguateDescription = true;
+        otherHandlerInfo.disambiguateDescription = true;
+      }
+    }
+  },
+
+  _rebuildView() {
+    // Clear the list of entries.
+    let tbody = this._handlerTbody;
+    while (tbody.hasChildNodes()) {
+      // Rows kept alive by the _handlerRows map.
+      tbody.removeChild(tbody.lastChild);
+    }
+
+    let sort = this._handlerSort;
+    for (let header of this._handlerSortHeaders) {
+      let icon = header.querySelector("img");
+      if (sort.type === header.getAttribute("sort-type")) {
+        icon.setAttribute(
+          "src",
+          "chrome://messenger/skin/icons/new/nav-down-sm.svg"
+        );
+        if (sort.descending) {
+          /* Rotates the src image to point up. */
+          icon.setAttribute("descending", "");
+          header.setAttribute("aria-sort", "descending");
+        } else {
+          icon.removeAttribute("descending");
+          header.setAttribute("aria-sort", "ascending");
+        }
+      } else {
+        icon.removeAttribute("src");
+        header.setAttribute("aria-sort", "none");
+      }
+    }
+
+    let visibleTypes = this._visibleTypes;
+
+    // If the user is filtering the list, then only show matching types.
+    if (this._filter.value) {
+      visibleTypes = visibleTypes.filter(this._matchesFilter, this);
+    }
+
+    for (let handlerInfo of visibleTypes) {
+      let row = this._handlerRows.get(handlerInfo);
+      if (row) {
+        tbody.appendChild(row.node);
+      } else {
+        row = new HandlerRow(handlerInfo, this.onDelete.bind(this));
+        row.constructNodeAndAppend(tbody, this._handlerMenuId);
+        this._handlerMenuId++;
+        this._handlerRows.set(handlerInfo, row);
+      }
+    }
+  },
+
+  _matchesFilter(aType) {
+    var filterValue = this._filter.value.toLowerCase();
+    return (
+      aType.typeDescription.toLowerCase().includes(filterValue) ||
+      aType.actionDescription.toLowerCase().includes(filterValue)
+    );
+  },
+
+  /**
+   * Get the details for the type represented by the given handler info
+   * object.
+   *
+   * @param aHandlerInfo {nsIHandlerInfo} the type to get the extensions for.
+   * @returns {string} the extensions for the type
+   */
+  _typeDetails(aHandlerInfo) {
+    let exts = [];
+    if (aHandlerInfo.wrappedHandlerInfo instanceof Ci.nsIMIMEInfo) {
+      for (let extName of aHandlerInfo.wrappedHandlerInfo.getFileExtensions()) {
+        let ext = "." + extName;
+        if (!exts.includes(ext)) {
+          exts.push(ext);
+        }
+      }
+    }
+    exts.sort();
+    exts = exts.join(", ");
+    if (this._visibleDescriptions.has(aHandlerInfo.description)) {
+      if (exts) {
+        return this._prefsBundle.getFormattedString(
+          "typeDetailsWithTypeAndExt",
+          [aHandlerInfo.type, exts]
+        );
+      }
+      return this._prefsBundle.getFormattedString("typeDetailsWithTypeOrExt", [
+        aHandlerInfo.type,
+      ]);
+    }
+    if (exts) {
+      return this._prefsBundle.getFormattedString("typeDetailsWithTypeOrExt", [
+        exts,
+      ]);
+    }
+    return exts;
+  },
+
+  /**
+   * Whether or not the given handler app is valid.
+   *
+   * @param aHandlerApp {nsIHandlerApp} the handler app in question
+   * @returns {boolean} whether or not it's valid
+   */
+  isValidHandlerApp(aHandlerApp) {
+    if (!aHandlerApp) {
+      return false;
+    }
+
+    if (aHandlerApp instanceof Ci.nsILocalHandlerApp) {
+      return this._isValidHandlerExecutable(aHandlerApp.executable);
+    }
+
+    if (aHandlerApp instanceof Ci.nsIWebHandlerApp) {
+      return aHandlerApp.uriTemplate;
+    }
+
+    if (aHandlerApp instanceof Ci.nsIWebContentHandlerInfo) {
+      return aHandlerApp.uri;
+    }
+
+    return false;
+  },
+
+  _isValidHandlerExecutable(aExecutable) {
+    let isExecutable =
+      aExecutable && aExecutable.exists() && aExecutable.isExecutable();
+    // XXXben - we need to compare this with the running instance executable
+    //          just don't know how to do that via script...
+    // XXXmano TBD: can probably add this to nsIShellService
+    if (AppConstants.platform == "win") {
+      return (
+        isExecutable &&
+        aExecutable.leafName != AppConstants.MOZ_APP_NAME + ".exe"
+      );
+    }
+
+    if (AppConstants.platform == "macosx") {
+      return (
+        isExecutable && aExecutable.leafName != AppConstants.MOZ_MACBUNDLE_NAME
+      );
+    }
+
+    return (
+      isExecutable && aExecutable.leafName != AppConstants.MOZ_APP_NAME + "-bin"
+    );
+  },
+
+  // -------------------
+  // Sorting & Filtering
+
+  /**
+   * Sort the list when the user clicks on a column header. If sortType is
+   * different than the last sort, the sort direction is toggled. Otherwise, the
+   * sort is changed to the new sortType with ascending direction.
+   *
+   * @param {string} sortType - The sort type associated with the column header.
+   */
+  sort(sortType) {
+    let sort = this._handlerSort;
+    if (sort.type === sortType) {
+      sort.descending = !sort.descending;
+    } else {
+      sort.type = sortType;
+      sort.descending = false;
+    }
+    this._sortVisibleTypes();
+    this._rebuildView();
+  },
+
+  /**
+   * Sort the list of visible types by the current sort column/direction.
+   */
+  _sortVisibleTypes() {
+    function sortByType(a, b) {
+      return a.typeDescription
+        .toLowerCase()
+        .localeCompare(b.typeDescription.toLowerCase());
+    }
+
+    function sortByAction(a, b) {
+      return a.actionDescription
+        .toLowerCase()
+        .localeCompare(b.actionDescription.toLowerCase());
+    }
+
+    let sort = this._handlerSort;
+    if (sort.type === "action") {
+      this._visibleTypes.sort(sortByAction);
+    } else {
+      this._visibleTypes.sort(sortByType);
+    }
+    if (sort.descending) {
+      this._visibleTypes.reverse();
+    }
+  },
+
+  focusFilterBox() {
+    this._filter.focus();
+    this._filter.select();
+  },
+
+  onDelete(handlerRow) {
+    let handlerInfo = handlerRow.handlerInfoWrapper;
+    let index = this._visibleTypes.indexOf(handlerInfo);
+    if (index != -1) {
+      this._visibleTypes.splice(index, 1);
+    }
+
+    let tbody = this._handlerTbody;
+    if (handlerRow.node.parentNode === tbody) {
+      tbody.removeChild(handlerRow.node);
+    }
+
+    this._handledTypes.delete(handlerInfo.type);
+    this._handlerRows.delete(handlerInfo);
+
+    handlerInfo.remove();
+  },
+
+  _getIconURLForHandlerApp(aHandlerApp) {
+    if (aHandlerApp instanceof Ci.nsILocalHandlerApp) {
+      return this._getIconURLForFile(aHandlerApp.executable);
+    }
+
+    if (aHandlerApp instanceof Ci.nsIWebHandlerApp) {
+      return this._getIconURLForWebApp(aHandlerApp.uriTemplate);
+    }
+
+    if (aHandlerApp instanceof Ci.nsIWebContentHandlerInfo) {
+      return this._getIconURLForWebApp(aHandlerApp.uri);
+    }
+
+    // We know nothing about other kinds of handler apps.
+    return "";
+  },
+
+  _getIconURLForFile(aFile) {
+    let urlSpec = Services.io
+      .getProtocolHandler("file")
+      .QueryInterface(Ci.nsIFileProtocolHandler)
+      .getURLSpecFromActualFile(aFile);
+
+    return "moz-icon://" + urlSpec + "?size=16";
+  },
+
+  _getIconURLForWebApp(aWebAppURITemplate) {
+    var uri = Services.io.newURI(aWebAppURITemplate);
+
+    // Unfortunately we can't use the favicon service to get the favicon,
+    // because the service looks in the annotations table for a record with
+    // the exact URL we give it, and users won't have such records for URLs
+    // they don't visit, and users won't visit the web app's URL template,
+    // they'll only visit URLs derived from that template (i.e. with %s
+    // in the template replaced by the URL of the content being handled).
+
+    if (/^https?/.test(uri.scheme)) {
+      return uri.prePath + "/favicon.ico";
+    }
+
+    return /^https?/.test(uri.scheme) ? uri.resolve("/favicon.ico") : "";
+  },
+
+  destroy() {
+    window.removeEventListener("unload", this);
+
+    Services.obs.removeObserver(this, AUTO_UPDATE_CHANGED_TOPIC);
+    Services.prefs.removeObserver("mailnews.tags.", this);
+  },
+
+  // nsISupports
+
+  QueryInterface: ChromeUtils.generateQI(["nsIObserver"]),
+
+  // nsIObserver
+
+  async observe(subject, topic, data) {
+    if (topic == AUTO_UPDATE_CHANGED_TOPIC) {
+      if (data != "true" && data != "false") {
+        throw new Error(`Invalid value for app.update.auto ${data}`);
+      }
+      document.getElementById("updateRadioGroup").value = data;
+    } else if (topic == "nsPref:changed" && data.startsWith("mailnews.tags.")) {
+      let selIndex = this.mTagListBox.selectedIndex;
+      this.mTagListBox.replaceChildren();
+      this.buildTagList();
+      let numItemsInListBox = this.mTagListBox.getRowCount();
+      this.mTagListBox.selectedIndex =
+        selIndex < numItemsInListBox ? selIndex : numItemsInListBox - 1;
+      if (data.endsWith(".color") && Services.prefs.prefHasUserValue(data)) {
+        let key = data.replace(/^mailnews\.tags\./, "").replace(/\.color$/, "");
+        let color = Services.prefs.getCharPref(`mailnews.tags.${key}.color`);
+        // Add to style sheet. We simply add the new color, the rule is added
+        // at the end and will overrule the previous rule.
+        TagUtils.addTagToAllDocumentSheets(key, color);
+      }
+    }
+  },
+
+  // EventListener
+
+  handleEvent(aEvent) {
+    if (aEvent.type == "unload") {
+      this.destroy();
+      if (AppConstants.MOZ_UPDATER) {
+        onUnload();
+      }
+    }
+  },
+};
+
+function getDisplayNameForFile(aFile) {
+  if (AppConstants.platform == "win") {
+    if (aFile instanceof Ci.nsILocalFileWin) {
+      try {
+        return aFile.getVersionInfoField("FileDescription");
+      } catch (ex) {
+        // fall through to the file name
+      }
+    }
+  } else if (AppConstants.platform == "macosx") {
+    if (aFile instanceof Ci.nsILocalFileMac) {
+      try {
+        return aFile.bundleDisplayName;
+      } catch (ex) {
+        // fall through to the file name
+      }
+    }
+  }
+
+  return aFile.leafName;
+}
+
+function getLocalHandlerApp(aFile) {
+  var localHandlerApp = Cc[
+    "@mozilla.org/uriloader/local-handler-app;1"
+  ].createInstance(Ci.nsILocalHandlerApp);
+  localHandlerApp.name = getDisplayNameForFile(aFile);
+  localHandlerApp.executable = aFile;
+
+  return localHandlerApp;
+}
+
+// eslint-disable-next-line no-undef
+let gHandlerRowFragment = MozXULElement.parseXULToFragment(`
+  <html:tr>
+    <html:td class="typeCell">
+      <html:div class="typeLabel">
+        <html:img class="typeIcon" alt=""/>
+        <label class="typeDescription" crop="end"/>
+      </html:div>
+    </html:td>
+    <html:td class="actionCell">
+      <menulist class="actionsMenu" crop="end" selectedIndex="1">
+        <menupopup/>
+      </menulist>
+    </html:td>
+  </html:tr>
+`);
+
+/**
+ * This is associated to rows in the handlers table.
+ */
+class HandlerRow {
+  constructor(handlerInfoWrapper, onDeleteCallback) {
+    this.handlerInfoWrapper = handlerInfoWrapper;
+    this.previousSelectedItem = null;
+    this.deleteCallback = onDeleteCallback;
+  }
+
+  constructNodeAndAppend(tbody, id) {
+    tbody.appendChild(document.importNode(gHandlerRowFragment, true));
+    this.node = tbody.lastChild;
+
+    this.menu = this.node.querySelector(".actionsMenu");
+    id = `action-menu-${id}`;
+    this.menu.setAttribute("id", id);
+    this.menu.addEventListener("command", event =>
+      this.onSelectAction(event.originalTarget)
+    );
+
+    let typeDescription = this.node.querySelector(".typeDescription");
+    typeDescription.setAttribute(
+      "value",
+      this.handlerInfoWrapper.typeDescription
+    );
+    // NOTE: Control only works for a XUL <label>. Using a HTML <label> and the
+    // corresponding "for" attribute would not currently work with the XUL
+    // <menulist> because a XUL <menulist> is technically not a labelable
+    // element, as required for the html:label "for" attribute.
+    typeDescription.setAttribute("control", id);
+    // Spoof the HTML label "for" attribute focus behaviour on the whole cell.
+    this.node
+      .querySelector(".typeCell")
+      .addEventListener("click", () => this.menu.focus());
+
+    this.node
+      .querySelector(".typeIcon")
+      .setAttribute("src", this.handlerInfoWrapper.smallIcon);
+
+    this.rebuildActionsMenu();
+  }
+
+  rebuildActionsMenu() {
+    let menu = this.menu;
+    let menuPopup = menu.menupopup;
+    let handlerInfo = this.handlerInfoWrapper;
+
+    // Clear out existing items.
+    while (menuPopup.hasChildNodes()) {
+      menuPopup.removeChild(menuPopup.lastChild);
+    }
+
+    let internalMenuItem;
+    // Add the "Preview in Thunderbird" option for optional internal handlers.
+    if (handlerInfo instanceof InternalHandlerInfoWrapper) {
+      internalMenuItem = document.createXULElement("menuitem");
+      internalMenuItem.setAttribute(
+        "action",
+        Ci.nsIHandlerInfo.handleInternally
+      );
+      let label = gGeneralPane._prefsBundle.getFormattedString("previewInApp", [
+        gGeneralPane._brandShortName,
+      ]);
+      internalMenuItem.setAttribute("label", label);
+      internalMenuItem.setAttribute("tooltiptext", label);
+      internalMenuItem.setAttribute(
+        "image",
+        "chrome://messenger/skin/preferences/alwaysAsk.png"
+      );
+      menuPopup.appendChild(internalMenuItem);
+    }
+
+    let askMenuItem = document.createXULElement("menuitem");
+    askMenuItem.setAttribute("alwaysAsk", "true");
+    {
+      let label = gGeneralPane._prefsBundle.getString("alwaysAsk");
+      askMenuItem.setAttribute("label", label);
+      askMenuItem.setAttribute("tooltiptext", label);
+      askMenuItem.setAttribute(
+        "image",
+        "chrome://messenger/skin/preferences/alwaysAsk.png"
+      );
+      menuPopup.appendChild(askMenuItem);
+    }
+
+    // Create a menu item for saving to disk.
+    // Note: this option isn't available to protocol types, since we don't know
+    // what it means to save a URL having a certain scheme to disk.
+    let saveMenuItem;
+    if (handlerInfo.wrappedHandlerInfo instanceof Ci.nsIMIMEInfo) {
+      saveMenuItem = document.createXULElement("menuitem");
+      saveMenuItem.setAttribute("action", Ci.nsIHandlerInfo.saveToDisk);
+      let label = gGeneralPane._prefsBundle.getString("saveFile");
+      saveMenuItem.setAttribute("label", label);
+      saveMenuItem.setAttribute("tooltiptext", label);
+      saveMenuItem.setAttribute(
+        "image",
+        "chrome://messenger/skin/preferences/saveFile.png"
+      );
+      menuPopup.appendChild(saveMenuItem);
+    }
+
+    // Add a separator to distinguish these items from the helper app items
+    // that follow them.
+    let menuItem = document.createXULElement("menuseparator");
+    menuPopup.appendChild(menuItem);
+
+    // Create a menu item for the OS default application, if any.
+    let defaultMenuItem;
+    if (handlerInfo.hasDefaultHandler) {
+      defaultMenuItem = document.createXULElement("menuitem");
+      defaultMenuItem.setAttribute(
+        "action",
+        Ci.nsIHandlerInfo.useSystemDefault
+      );
+      let label = gGeneralPane._prefsBundle.getFormattedString("useDefault", [
+        handlerInfo.defaultDescription,
+      ]);
+      defaultMenuItem.setAttribute("label", label);
+      defaultMenuItem.setAttribute(
+        "tooltiptext",
+        handlerInfo.defaultDescription
+      );
+      defaultMenuItem.setAttribute(
+        "image",
+        handlerInfo.iconURLForSystemDefault
+      );
+
+      menuPopup.appendChild(defaultMenuItem);
+    }
+
+    // Create menu items for possible handlers.
+    let preferredApp = handlerInfo.preferredApplicationHandler;
+    let possibleAppMenuItems = [];
+    for (let possibleApp of handlerInfo.possibleApplicationHandlers.enumerate()) {
+      if (!gGeneralPane.isValidHandlerApp(possibleApp)) {
+        continue;
+      }
+
+      let menuItem = document.createXULElement("menuitem");
+      menuItem.setAttribute("action", Ci.nsIHandlerInfo.useHelperApp);
+      let label;
+      if (possibleApp instanceof Ci.nsILocalHandlerApp) {
+        label = getDisplayNameForFile(possibleApp.executable);
+      } else {
+        label = possibleApp.name;
+      }
+      label = gGeneralPane._prefsBundle.getFormattedString("useApp", [label]);
+      menuItem.setAttribute("label", label);
+      menuItem.setAttribute("tooltiptext", label);
+      menuItem.setAttribute(
+        "image",
+        gGeneralPane._getIconURLForHandlerApp(possibleApp)
+      );
+
+      // Attach the handler app object to the menu item so we can use it
+      // to make changes to the datastore when the user selects the item.
+      menuItem.handlerApp = possibleApp;
+
+      menuPopup.appendChild(menuItem);
+      possibleAppMenuItems.push(menuItem);
+    }
+
+    // Create a menu item for selecting a local application.
+    let createItem = true;
+    if (AppConstants.platform == "win") {
+      // On Windows, selecting an application to open another application
+      // would be meaningless so we special case executables.
+      let executableType = Cc["@mozilla.org/mime;1"]
+        .getService(Ci.nsIMIMEService)
+        .getTypeFromExtension("exe");
+      if (handlerInfo.type == executableType) {
+        createItem = false;
+      }
+    }
+
+    if (createItem) {
+      let menuItem = document.createXULElement("menuitem");
+      menuItem.addEventListener("command", this.chooseApp.bind(this));
+      let label = gGeneralPane._prefsBundle.getString("useOtherApp");
+      menuItem.setAttribute("label", label);
+      menuItem.setAttribute("tooltiptext", label);
+      menuPopup.appendChild(menuItem);
+    }
+
+    // Create a menu item for managing applications.
+    if (possibleAppMenuItems.length) {
+      let menuItem = document.createXULElement("menuseparator");
+      menuPopup.appendChild(menuItem);
+      menuItem = document.createXULElement("menuitem");
+      menuItem.addEventListener("command", this.manageApp.bind(this));
+      menuItem.setAttribute(
+        "label",
+        gGeneralPane._prefsBundle.getString("manageApp")
+      );
+      menuPopup.appendChild(menuItem);
+    }
+
+    menuItem = document.createXULElement("menuseparator");
+    menuPopup.appendChild(menuItem);
+    menuItem = document.createXULElement("menuitem");
+    menuItem.addEventListener("command", this.confirmDelete.bind(this));
+    menuItem.setAttribute(
+      "label",
+      gGeneralPane._prefsBundle.getString("delete")
+    );
+    menuPopup.appendChild(menuItem);
+
+    // Select the item corresponding to the preferred action.  If the always
+    // ask flag is set, it overrides the preferred action.  Otherwise we pick
+    // the item identified by the preferred action (when the preferred action
+    // is to use a helper app, we have to pick the specific helper app item).
+    if (handlerInfo.alwaysAskBeforeHandling) {
+      menu.selectedItem = askMenuItem;
+    } else {
+      switch (handlerInfo.preferredAction) {
+        case Ci.nsIHandlerInfo.handleInternally:
+          if (internalMenuItem) {
+            menu.selectedItem = internalMenuItem;
+          } else {
+            console.error("No menu item defined to set!");
+          }
+          break;
+        case Ci.nsIHandlerInfo.useSystemDefault:
+          menu.selectedItem = defaultMenuItem;
+          break;
+        case Ci.nsIHandlerInfo.useHelperApp:
+          if (preferredApp) {
+            menu.selectedItem = possibleAppMenuItems.filter(v =>
+              v.handlerApp.equals(preferredApp)
+            )[0];
+          }
+          break;
+        case Ci.nsIHandlerInfo.saveToDisk:
+          menu.selectedItem = saveMenuItem;
+          break;
+      }
+    }
+    // menu.selectedItem may be null if the preferredAction is
+    // useSystemDefault, but handlerInfo.hasDefaultHandler returns false.
+    // For now, we'll just use the askMenuItem to avoid ugly exceptions.
+    this.previousSelectedItem = this.menu.selectedItem || askMenuItem;
+  }
+
+  manageApp(aEvent) {
+    // Don't let the normal "on select action" handler get this event,
+    // as we handle it specially ourselves.
+    aEvent.stopPropagation();
+
+    var handlerInfo = this.handlerInfoWrapper;
+
+    let onComplete = () => {
+      // Rebuild the actions menu so that we revert to the previous selection,
+      // or "Always ask" if the previous default application has been removed.
+      this.rebuildActionsMenu();
+    };
+
+    gSubDialog.open(
+      "chrome://messenger/content/preferences/applicationManager.xhtml",
+      { features: "resizable=no", closingCallback: onComplete },
+      handlerInfo
+    );
+  }
+
+  chooseApp(aEvent) {
+    // Don't let the normal "on select action" handler get this event,
+    // as we handle it specially ourselves.
+    aEvent.stopPropagation();
+
+    var handlerApp;
+    let onSelectionDone = function () {
+      // Rebuild the actions menu whether the user picked an app or canceled.
+      // If they picked an app, we want to add the app to the menu and select it.
+      // If they canceled, we want to go back to their previous selection.
+      this.rebuildActionsMenu();
+
+      // If the user picked a new app from the menu, select it.
+      if (handlerApp) {
+        let menuItems = this.menu.menupopup.children;
+        for (let i = 0; i < menuItems.length; i++) {
+          let menuItem = menuItems[i];
+          if (menuItem.handlerApp && menuItem.handlerApp.equals(handlerApp)) {
+            this.menu.selectedIndex = i;
+            this.onSelectAction(menuItem);
+            break;
+          }
+        }
+      }
+    }.bind(this);
+
+    if (AppConstants.platform == "win") {
+      let params = {};
+      let handlerInfo = this.handlerInfoWrapper;
+
+      params.mimeInfo = handlerInfo.wrappedHandlerInfo;
+
+      params.title = gGeneralPane._prefsBundle.getString("fpTitleChooseApp");
+      params.description = handlerInfo.description;
+      params.filename = null;
+      params.handlerApp = null;
+
+      let onAppSelected = () => {
+        if (gGeneralPane.isValidHandlerApp(params.handlerApp)) {
+          handlerApp = params.handlerApp;
+
+          // Add the app to the type's list of possible handlers.
+          handlerInfo.addPossibleApplicationHandler(handlerApp);
+        }
+        onSelectionDone();
+      };
+
+      gSubDialog.open(
+        "chrome://global/content/appPicker.xhtml",
+        { features: "resizable=no", closingCallback: onAppSelected },
+        params
+      );
+    } else {
+      let fp = Cc["@mozilla.org/filepicker;1"].createInstance(Ci.nsIFilePicker);
+      let winTitle = gGeneralPane._prefsBundle.getString("fpTitleChooseApp");
+      fp.init(window, winTitle, Ci.nsIFilePicker.modeOpen);
+      fp.appendFilters(Ci.nsIFilePicker.filterApps);
+
+      // Prompt the user to pick an app.  If they pick one, and it's a valid
+      // selection, then add it to the list of possible handlers.
+
+      fp.open(rv => {
+        if (
+          rv == Ci.nsIFilePicker.returnOK &&
+          fp.file &&
+          gGeneralPane._isValidHandlerExecutable(fp.file)
+        ) {
+          handlerApp = Cc[
+            "@mozilla.org/uriloader/local-handler-app;1"
+          ].createInstance(Ci.nsILocalHandlerApp);
+          handlerApp.name = getDisplayNameForFile(fp.file);
+          handlerApp.executable = fp.file;
+
+          // Add the app to the type's list of possible handlers.
+          let handlerInfo = this.handlerInfoWrapper;
+          handlerInfo.addPossibleApplicationHandler(handlerApp);
+        }
+        onSelectionDone();
+      });
+    }
+  }
+
+  confirmDelete(aEvent) {
+    aEvent.stopPropagation();
+    if (
+      Services.prompt.confirm(
+        null,
+        gGeneralPane._prefsBundle.getString("confirmDeleteTitle"),
+        gGeneralPane._prefsBundle.getString("confirmDeleteText")
+      )
+    ) {
+      // Deletes self.
+      this.deleteCallback(this);
+    } else {
+      // They hit cancel, so return them to the previously selected item.
+      this.menu.selectedItem = this.previousSelectedItem;
+    }
+  }
+
+  onSelectAction(aActionItem) {
+    this.previousSelectedItem = aActionItem;
+    this._storeAction(aActionItem);
+  }
+
+  _storeAction(aActionItem) {
+    var handlerInfo = this.handlerInfoWrapper;
+
+    if (aActionItem.hasAttribute("alwaysAsk")) {
+      handlerInfo.alwaysAskBeforeHandling = true;
+    } else if (aActionItem.hasAttribute("action")) {
+      let action = parseInt(aActionItem.getAttribute("action"));
+
+      // Set the preferred application handler.
+      // We leave the existing preferred app in the list when we set
+      // the preferred action to something other than useHelperApp so that
+      // legacy datastores that don't have the preferred app in the list
+      // of possible apps still include the preferred app in the list of apps
+      // the user can choose to handle the type.
+      if (action == Ci.nsIHandlerInfo.useHelperApp) {
+        handlerInfo.preferredApplicationHandler = aActionItem.handlerApp;
+      }
+
+      // Set the "always ask" flag.
+      handlerInfo.alwaysAskBeforeHandling = false;
+
+      // Set the preferred action.
+      handlerInfo.preferredAction = action;
+    }
+
+    handlerInfo.store();
+  }
+}
+
+/**
+ * This object wraps nsIHandlerInfo with some additional functionality
+ * the Applications prefpane needs to display and allow modification of
+ * the list of handled types.
+ *
+ * We create an instance of this wrapper for each entry we might display
+ * in the prefpane, and we compose the instances from various sources,
+ * including the handler service.
+ *
+ * We don't implement all the original nsIHandlerInfo functionality,
+ * just the stuff that the prefpane needs.
+ */
+class HandlerInfoWrapper {
+  constructor(type, handlerInfo) {
+    this.type = type;
+    this.wrappedHandlerInfo = handlerInfo;
+    this.disambiguateDescription = false;
+  }
+
+  get description() {
+    if (this.wrappedHandlerInfo.description) {
+      return this.wrappedHandlerInfo.description;
+    }
+
+    if (this.primaryExtension) {
+      var extension = this.primaryExtension.toUpperCase();
+      return document
+        .getElementById("bundlePreferences")
+        .getFormattedString("fileEnding", [extension]);
+    }
+    return this.type;
+  }
+
+  /**
+   * Describe, in a human-readable fashion, the type represented by the given
+   * handler info object.  Normally this is just the description, but if more
+   * than one object presents the same description, "disambiguateDescription"
+   * is set and we annotate the duplicate descriptions with the type itself
+   * to help users distinguish between those types.
+   */
+  get typeDescription() {
+    if (this.disambiguateDescription) {
+      return gGeneralPane._prefsBundle.getFormattedString(
+        "typeDetailsWithTypeAndExt",
+        [this.description, this.type]
+      );
+    }
+
+    return this.description;
+  }
+
+  /**
+   * Describe, in a human-readable fashion, the preferred action to take on
+   * the type represented by the given handler info object.
+   */
+  get actionDescription() {
+    // alwaysAskBeforeHandling overrides the preferred action, so if that flag
+    // is set, then describe that behavior instead.  For most types, this is
+    // the "alwaysAsk" string, but for the feed type we show something special.
+    if (this.alwaysAskBeforeHandling) {
+      return gGeneralPane._prefsBundle.getString("alwaysAsk");
+    }
+
+    switch (this.preferredAction) {
+      case Ci.nsIHandlerInfo.saveToDisk:
+        return gGeneralPane._prefsBundle.getString("saveFile");
+
+      case Ci.nsIHandlerInfo.useHelperApp:
+        var preferredApp = this.preferredApplicationHandler;
+        var name;
+        if (preferredApp instanceof Ci.nsILocalHandlerApp) {
+          name = getDisplayNameForFile(preferredApp.executable);
+        } else {
+          name = preferredApp.name;
+        }
+        return gGeneralPane._prefsBundle.getFormattedString("useApp", [name]);
+
+      case Ci.nsIHandlerInfo.handleInternally:
+        if (this instanceof InternalHandlerInfoWrapper) {
+          return gGeneralPane._prefsBundle.getFormattedString("previewInApp", [
+            gGeneralPane._brandShortName,
+          ]);
+        }
+
+        // For other types, handleInternally looks like either useHelperApp
+        // or useSystemDefault depending on whether or not there's a preferred
+        // handler app.
+        if (gGeneralPane.isValidHandlerApp(this.preferredApplicationHandler)) {
+          return this.preferredApplicationHandler.name;
+        }
+
+        return this.defaultDescription;
+
+      // XXX Why don't we say the app will handle the type internally?
+      // Is it because the app can't actually do that?  But if that's true,
+      // then why would a preferredAction ever get set to this value
+      // in the first place?
+
+      case Ci.nsIHandlerInfo.useSystemDefault:
+        return gGeneralPane._prefsBundle.getFormattedString("useDefault", [
+          this.defaultDescription,
+        ]);
+
+      default:
+        throw new Error(`Unexpected preferredAction: ${this.preferredAction}`);
+    }
+  }
+
+  get actionIconClass() {
+    if (this.alwaysAskBeforeHandling) {
+      return "ask";
+    }
+
+    switch (this.preferredAction) {
+      case Ci.nsIHandlerInfo.saveToDisk:
+        return "save";
+
+      case Ci.nsIHandlerInfo.handleInternally:
+        if (this instanceof InternalHandlerInfoWrapper) {
+          return "ask";
+        }
+    }
+
+    return "";
+  }
+
+  get actionIcon() {
+    switch (this.preferredAction) {
+      case Ci.nsIHandlerInfo.useSystemDefault:
+        return this.iconURLForSystemDefault;
+
+      case Ci.nsIHandlerInfo.useHelperApp:
+        let preferredApp = this.preferredApplicationHandler;
+        if (gGeneralPane.isValidHandlerApp(preferredApp)) {
+          return gGeneralPane._getIconURLForHandlerApp(preferredApp);
+        }
+      // This should never happen, but if preferredAction is set to some weird
+      // value, then fall back to the generic application icon.
+
+      // Explicit fall-through
+      default:
+        return ICON_URL_APP;
+    }
+  }
+
+  get iconURLForSystemDefault() {
+    // Handler info objects for MIME types on some OSes implement a property bag
+    // interface from which we can get an icon for the default app, so if we're
+    // dealing with a MIME type on one of those OSes, then try to get the icon.
+    if (
+      this.wrappedHandlerInfo instanceof Ci.nsIMIMEInfo &&
+      this.wrappedHandlerInfo instanceof Ci.nsIPropertyBag
+    ) {
+      try {
+        let url = this.wrappedHandlerInfo.getProperty(
+          "defaultApplicationIconURL"
+        );
+        if (url) {
+          return url + "?size=16";
+        }
+      } catch (ex) {}
+    }
+
+    // If this isn't a MIME type object on an OS that supports retrieving
+    // the icon, or if we couldn't retrieve the icon for some other reason,
+    // then use a generic icon.
+    return ICON_URL_APP;
+  }
+
+  get preferredApplicationHandler() {
+    return this.wrappedHandlerInfo.preferredApplicationHandler;
+  }
+
+  set preferredApplicationHandler(aNewValue) {
+    this.wrappedHandlerInfo.preferredApplicationHandler = aNewValue;
+
+    // Make sure the preferred handler is in the set of possible handlers.
+    if (aNewValue) {
+      this.addPossibleApplicationHandler(aNewValue);
+    }
+  }
+
+  get possibleApplicationHandlers() {
+    return this.wrappedHandlerInfo.possibleApplicationHandlers;
+  }
+
+  addPossibleApplicationHandler(aNewHandler) {
+    for (let possibleApp of this.possibleApplicationHandlers.enumerate()) {
+      if (possibleApp.equals(aNewHandler)) {
+        return;
+      }
+    }
+    this.possibleApplicationHandlers.appendElement(aNewHandler);
+  }
+
+  removePossibleApplicationHandler(aHandler) {
+    var defaultApp = this.preferredApplicationHandler;
+    if (defaultApp && aHandler.equals(defaultApp)) {
+      // If the app we remove was the default app, we must make sure
+      // it won't be used anymore
+      this.alwaysAskBeforeHandling = true;
+      this.preferredApplicationHandler = null;
+    }
+
+    var handlers = this.possibleApplicationHandlers;
+    for (var i = 0; i < handlers.length; ++i) {
+      var handler = handlers.queryElementAt(i, Ci.nsIHandlerApp);
+      if (handler.equals(aHandler)) {
+        handlers.removeElementAt(i);
+        break;
+      }
+    }
+  }
+
+  get hasDefaultHandler() {
+    return this.wrappedHandlerInfo.hasDefaultHandler;
+  }
+
+  get defaultDescription() {
+    return this.wrappedHandlerInfo.defaultDescription;
+  }
+
+  // What to do with content of this type.
+  get preferredAction() {
+    // If the action is to use a helper app, but we don't have a preferred
+    // handler app, then switch to using the system default, if any; otherwise
+    // fall back to saving to disk, which is the default action in nsMIMEInfo.
+    // Note: "save to disk" is an invalid value for protocol info objects,
+    // but the alwaysAskBeforeHandling getter will detect that situation
+    // and always return true in that case to override this invalid value.
+    if (
+      this.wrappedHandlerInfo.preferredAction ==
+        Ci.nsIHandlerInfo.useHelperApp &&
+      !gGeneralPane.isValidHandlerApp(this.preferredApplicationHandler)
+    ) {
+      if (this.wrappedHandlerInfo.hasDefaultHandler) {
+        return Ci.nsIHandlerInfo.useSystemDefault;
+      }
+      return Ci.nsIHandlerInfo.saveToDisk;
+    }
+
+    return this.wrappedHandlerInfo.preferredAction;
+  }
+
+  set preferredAction(aNewValue) {
+    this.wrappedHandlerInfo.preferredAction = aNewValue;
+  }
+
+  get alwaysAskBeforeHandling() {
+    // If this is a protocol type and the preferred action is "save to disk",
+    // which is invalid for such types, then return true here to override that
+    // action.  This could happen when the preferred action is to use a helper
+    // app, but the preferredApplicationHandler is invalid, and there isn't
+    // a default handler, so the preferredAction getter returns save to disk
+    // instead.
+    if (
+      !(this.wrappedHandlerInfo instanceof Ci.nsIMIMEInfo) &&
+      this.preferredAction == Ci.nsIHandlerInfo.saveToDisk
+    ) {
+      return true;
+    }
+
+    return this.wrappedHandlerInfo.alwaysAskBeforeHandling;
+  }
+
+  set alwaysAskBeforeHandling(aNewValue) {
+    this.wrappedHandlerInfo.alwaysAskBeforeHandling = aNewValue;
+  }
+
+  // The primary file extension associated with this type, if any.
+  get primaryExtension() {
+    try {
+      if (
+        this.wrappedHandlerInfo instanceof Ci.nsIMIMEInfo &&
+        this.wrappedHandlerInfo.primaryExtension
+      ) {
+        return this.wrappedHandlerInfo.primaryExtension;
+      }
+    } catch (ex) {}
+
+    return null;
+  }
+
+  // -------
+  // Storage
+
+  store() {
+    gHandlerService.store(this.wrappedHandlerInfo);
+  }
+
+  remove() {
+    gHandlerService.remove(this.wrappedHandlerInfo);
+  }
+
+  // -----
+  // Icons
+
+  get smallIcon() {
+    return this._getIcon(16);
+  }
+
+  get largeIcon() {
+    return this._getIcon(32);
+  }
+
+  _getIcon(aSize) {
+    if (this.primaryExtension) {
+      return "moz-icon://goat." + this.primaryExtension + "?size=" + aSize;
+    }
+
+    if (this.wrappedHandlerInfo instanceof Ci.nsIMIMEInfo) {
+      return "moz-icon://goat?size=" + aSize + "&contentType=" + this.type;
+    }
+
+    // FIXME: consider returning some generic icon when we can't get a URL for
+    // one (for example in the case of protocol schemes).  Filed as bug 395141.
+    return null;
+  }
+}
+
+/**
+ * InternalHandlerInfoWrapper provides a basic mechanism to create an internal
+ * mime type handler that can be enabled/disabled in the applications preference
+ * menu.
+ */
+class InternalHandlerInfoWrapper extends HandlerInfoWrapper {
+  constructor(mimeType) {
+    super(mimeType, gMIMEService.getFromTypeAndExtension(mimeType, null));
+  }
+
+  // Override store so we so we can notify any code listening for registration
+  // or unregistration of this handler.
+  store() {
+    super.store();
+  }
+
+  get enabled() {
+    throw Components.Exception("", Cr.NS_ERROR_NOT_IMPLEMENTED);
+  }
+
+  get description() {
+    return gGeneralPane._prefsBundle.getString(this._appPrefLabel);
+  }
+}
+
+class PDFHandlerInfoWrapper extends InternalHandlerInfoWrapper {
+  constructor() {
+    super(TYPE_PDF);
+  }
+
+  get _appPrefLabel() {
+    return "applications-type-pdf";
+  }
+
+  get enabled() {
+    return !Services.prefs.getBoolPref(PREF_PDFJS_DISABLED);
+  }
+}
+
+function addTagCallback(aName, aColor) {
+  MailServices.tags.addTag(aName, aColor, "");
+
+  // Add to style sheet.
+  let key = MailServices.tags.getKeyForTag(aName);
+  let tagListBox = document.getElementById("tagList");
+  let item = tagListBox.querySelector(`richlistitem[value=${key}]`);
+  tagListBox.ensureElementIsVisible(item);
+  tagListBox.selectItem(item);
+  tagListBox.focus();
+  return true;
+}
+
+Preferences.get("mailnews.start_page.enabled").on(
+  "change",
+  gGeneralPane.updateStartPage
+);
+Preferences.get("font.language.group").on("change", gGeneralPane._rebuildFonts);
+Preferences.get("mailnews.mark_message_read.auto").on(
+  "change",
+  gGeneralPane.updateMarkAsReadOptions
+);
+Preferences.get("mailnews.mark_message_read.delay").on(
+  "change",
+  gGeneralPane.updateMarkAsReadTextbox
+);
+Preferences.get("mail.prompt_purge_threshhold").on(
+  "change",
+  gGeneralPane.updateCompactOptions
+);
+Preferences.get("layers.acceleration.disabled").on(
+  "change",
+  gGeneralPane.updateHardwareAcceleration
+);
+if (AppConstants.platform != "macosx") {
+  Preferences.get("mail.biff.show_alert").on(
+    "change",
+    gGeneralPane.updateShowAlert
+  );
+}
diff --git a/comm/mail/components/preferences/jar.mn b/comm/mail/components/preferences/jar.mn
new file mode 100644
index 0000000000..fc9b56184e
--- /dev/null
+++ b/comm/mail/components/preferences/jar.mn
@@ -0,0 +1,55 @@
+# 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/.
+
+messenger.jar:
+*   content/messenger/preferences/preferences.xhtml
+    content/messenger/preferences/preferences.js
+    content/messenger/preferences/preferencesTab.js
+    content/messenger/preferences/general.js
+#if defined(XP_MACOSX) || defined(XP_WIN)
+    content/messenger/preferences/dockoptions.js
+*   content/messenger/preferences/dockoptions.xhtml
+#endif
+    content/messenger/preferences/chat.js
+#ifdef NIGHTLY_BUILD
+    content/messenger/preferences/sync.js
+#endif
+    content/messenger/preferences/messagestyle.js
+    content/messenger/preferences/messengerLanguages.js
+    content/messenger/preferences/messengerLanguages.xhtml
+    content/messenger/preferences/colors.js
+*   content/messenger/preferences/colors.xhtml
+    content/messenger/preferences/compose.js
+    content/messenger/preferences/extensionControlled.js
+    content/messenger/preferences/privacy.js
+    content/messenger/preferences/receipts.js
+    content/messenger/preferences/receipts.xhtml
+    content/messenger/preferences/connection.js
+    content/messenger/preferences/connection.xhtml
+    content/messenger/preferences/downloads.js
+    content/messenger/preferences/attachmentReminder.js
+    content/messenger/preferences/attachmentReminder.xhtml
+    content/messenger/preferences/applicationManager.xhtml
+    content/messenger/preferences/applicationManager.js
+    content/messenger/preferences/actionsshared.js
+    content/messenger/preferences/findInPage.js
+    content/messenger/preferences/fonts.js
+    content/messenger/preferences/fonts.xhtml
+#ifndef XP_MACOSX
+    content/messenger/preferences/notifications.js
+    content/messenger/preferences/notifications.xhtml
+#endif
+    content/messenger/preferences/offline.js
+    content/messenger/preferences/offline.xhtml
+    content/messenger/preferences/cookies.js
+*   content/messenger/preferences/cookies.xhtml
+    content/messenger/preferences/passwordManager.js
+    content/messenger/preferences/passwordManager.xhtml
+    content/messenger/preferences/permissions.js
+    content/messenger/preferences/permissions.xhtml
+#ifdef NIGHTLY_BUILD
+    content/messenger/preferences/syncDialog.js
+    content/messenger/preferences/syncDialog.xhtml
+#endif
+*   content/messenger/preferences/tagDialog.xhtml
diff --git a/comm/mail/components/preferences/messagestyle.js b/comm/mail/components/preferences/messagestyle.js
new file mode 100644
index 0000000000..7d10553296
--- /dev/null
+++ b/comm/mail/components/preferences/messagestyle.js
@@ -0,0 +1,259 @@
+/* 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-globals-from preferences.js */
+
+var { GenericConvIMPrototype, GenericMessagePrototype } =
+  ChromeUtils.importESModule("resource:///modules/jsProtoHelper.sys.mjs");
+var { getThemeByName, getThemeVariants } = ChromeUtils.importESModule(
+  "resource:///modules/imThemes.sys.mjs"
+);
+
+var { IMServices } = ChromeUtils.importESModule(
+  "resource:///modules/IMServices.sys.mjs"
+);
+
+function Conversation(aName) {
+  this._name = aName;
+  this._observers = [];
+  let now = new Date();
+  this._date =
+    new Date(now.getFullYear(), now.getMonth(), now.getDate(), 10, 42, 22) *
+    1000;
+}
+Conversation.prototype = {
+  __proto__: GenericConvIMPrototype,
+  account: {
+    protocol: { name: "Fake Protocol" },
+    alias: "",
+    name: "Fake Account",
+    get statusInfo() {
+      return IMServices.core.globalUserStatus;
+    },
+  },
+};
+
+function Message(aWho, aMessage, aObject, aConversation) {
+  this._init(aWho, aMessage, aObject, aConversation);
+}
+Message.prototype = {
+  __proto__: GenericMessagePrototype,
+  get displayMessage() {
+    return this.originalMessage;
+  },
+};
+
+// Message style tooltips use this.
+function getBrowser() {
+  return document.getElementById("previewbrowser");
+}
+
+var previewObserver = {
+  _loaded: false,
+  load() {
+    let makeDate = function (aDateString) {
+      let array = aDateString.split(":");
+      let now = new Date();
+      return (
+        new Date(
+          now.getFullYear(),
+          now.getMonth(),
+          now.getDate(),
+          array[0],
+          array[1],
+          array[2]
+        ) / 1000
+      );
+    };
+    let bundle = document.getElementById("themesBundle");
+    let msg = {};
+    [
+      "nick1",
+      "buddy1",
+      "nick2",
+      "buddy2",
+      "message1",
+      "message2",
+      "message3",
+    ].forEach(function (aText) {
+      msg[aText] = bundle.getString(aText);
+    });
+    let conv = new Conversation(msg.nick2);
+    conv.messages = [
+      new Message(
+        msg.buddy1,
+        msg.message1,
+        {
+          outgoing: true,
+          _alias: msg.nick1,
+          time: makeDate("10:42:22"),
+        },
+        conv
+      ),
+      new Message(
+        msg.buddy1,
+        msg.message2,
+        {
+          outgoing: true,
+          _alias: msg.nick1,
+          time: makeDate("10:42:25"),
+        },
+        conv
+      ),
+      new Message(
+        msg.buddy2,
+        msg.message3,
+        {
+          incoming: true,
+          _alias: msg.nick2,
+          time: makeDate("10:43:01"),
+        },
+        conv
+      ),
+    ];
+    previewObserver.conv = conv;
+
+    let themeName = document.getElementById("messagestyle-themename");
+    previewObserver.browser = document.getElementById("previewbrowser");
+
+    // If the preferences tab is opened straight to the message styles,
+    // loading the preview fails. Pushing this to back of the event queue
+    // prevents that failure.
+    setTimeout(() => {
+      previewObserver.displayTheme(themeName.value);
+      this._loaded = true;
+    });
+  },
+
+  currentThemeChanged() {
+    if (!this._loaded) {
+      return;
+    }
+
+    let currentTheme = document.getElementById("messagestyle-themename").value;
+    if (!currentTheme) {
+      return;
+    }
+
+    this.displayTheme(currentTheme);
+  },
+
+  _ignoreVariantChange: false,
+  currentVariantChanged() {
+    if (!this._loaded || this._ignoreVariantChange) {
+      return;
+    }
+
+    let variant = document.getElementById("themevariant").value;
+    if (!variant) {
+      return;
+    }
+
+    this.theme.variant = variant;
+    this.reloadPreview();
+  },
+
+  displayTheme(aTheme) {
+    try {
+      this.theme = getThemeByName(aTheme);
+    } catch (e) {
+      let previewBoxBrowser = document
+        .getElementById("previewBox")
+        .querySelector("browser");
+      if (previewBoxBrowser) {
+        previewBoxBrowser.hidden = true;
+      }
+      document.getElementById("noPreviewScreen").hidden = false;
+      return;
+    }
+
+    let menulist = document.getElementById("themevariant");
+    if (menulist.menupopup) {
+      menulist.menupopup.remove();
+    }
+    let popup = menulist.appendChild(document.createXULElement("menupopup"));
+    let variants = getThemeVariants(this.theme);
+
+    let defaultVariant = "";
+    if (
+      "DefaultVariant" in this.theme.metadata &&
+      variants.includes(this.theme.metadata.DefaultVariant)
+    ) {
+      defaultVariant = this.theme.metadata.DefaultVariant.replace(/_/g, " ");
+    }
+
+    let defaultText = defaultVariant;
+    if (!defaultText && "DisplayNameForNoVariant" in this.theme.metadata) {
+      defaultText = this.theme.metadata.DisplayNameForNoVariant;
+    }
+    // if the name in the metadata is 'Default', use the localized version
+    if (!defaultText || defaultText.toLowerCase() == "default") {
+      defaultText = document
+        .getElementById("themesBundle")
+        .getString("default");
+    }
+
+    let menuitem = document.createXULElement("menuitem");
+    menuitem.setAttribute("label", defaultText);
+    menuitem.setAttribute("value", "default");
+    popup.appendChild(menuitem);
+    popup.appendChild(document.createXULElement("menuseparator"));
+
+    variants.sort().forEach(function (aVariantName) {
+      let displayName = aVariantName.replace(/_/g, " ");
+      if (displayName != defaultVariant) {
+        let menuitem = document.createXULElement("menuitem");
+        menuitem.setAttribute("label", displayName);
+        menuitem.setAttribute("value", aVariantName);
+        popup.appendChild(menuitem);
+      }
+    });
+    this._ignoreVariantChange = true;
+    if (!this._loaded) {
+      menulist.value = this.theme.variant = menulist.value;
+    } else {
+      menulist.value = this.theme.variant; // (reset to "default")
+      Preferences.userChangedValue(menulist);
+    }
+    this._ignoreVariantChange = false;
+
+    // disable the variant menulist if there's no variant, or only one
+    // which is the default
+    menulist.disabled =
+      variants.length == 0 || (variants.length == 1 && defaultVariant);
+
+    this.reloadPreview();
+    document.getElementById("noPreviewScreen").hidden = true;
+  },
+
+  reloadPreview() {
+    this.browser.init(this.conv);
+    this.browser._theme = this.theme;
+    Services.obs.addObserver(this, "conversation-loaded");
+  },
+
+  observe(aSubject, aTopic, aData) {
+    if (aTopic != "conversation-loaded" || aSubject != this.browser) {
+      return;
+    }
+
+    // We want to avoid the convbrowser trying to scroll to the last
+    // added message, as that causes the entire pref pane to jump up
+    // (bug 1179943). Therefore, we override the method convbrowser
+    // uses to determine if it should scroll, as well as its
+    // mirror in the contentWindow (that messagestyle JS can call).
+    this.browser.convScrollEnabled = () => false;
+    this.browser.contentWindow.convScrollEnabled = () => false;
+
+    // Display all queued messages. Use a timeout so that message text
+    // modifiers can be added with observers for this notification.
+    setTimeout(function () {
+      for (let message of previewObserver.conv.messages) {
+        aSubject.appendMessage(message, false);
+      }
+    }, 0);
+
+    Services.obs.removeObserver(this, "conversation-loaded");
+  },
+};
diff --git a/comm/mail/components/preferences/messengerLanguages.js b/comm/mail/components/preferences/messengerLanguages.js
new file mode 100644
index 0000000000..e66f5f7fd0
--- /dev/null
+++ b/comm/mail/components/preferences/messengerLanguages.js
@@ -0,0 +1,632 @@
+/* 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 is exported by preferences.js but we can't import that in a subdialog.
+let { getAvailableLocales } = window.top;
+
+ChromeUtils.defineESModuleGetters(this, {
+  AddonManager: "resource://gre/modules/AddonManager.sys.mjs",
+  AddonRepository: "resource://gre/modules/addons/AddonRepository.sys.mjs",
+});
+
+/* This dialog provides an interface for managing what language the messenger is
+ * displayed in.
+ *
+ * There is a list of "requested" locales and a list of "available" locales. The
+ * requested locales must be installed and enabled. Available locales could be
+ * installed and enabled, or fetched from the AMO language tools API.
+ *
+ * If a langpack is disabled, there is no way to determine what locale it is for and
+ * it will only be listed as available if that locale is also available on AMO and
+ * the user has opted to search for more languages.
+ */
+
+class OrderedListBox {
+  constructor({ richlistbox, upButton, downButton, removeButton, onRemove }) {
+    this.richlistbox = richlistbox;
+    this.upButton = upButton;
+    this.downButton = downButton;
+    this.removeButton = removeButton;
+    this.onRemove = onRemove;
+
+    this.items = [];
+
+    this.richlistbox.addEventListener("select", () => this.setButtonState());
+    this.upButton.addEventListener("command", () => this.moveUp());
+    this.downButton.addEventListener("command", () => this.moveDown());
+    this.removeButton.addEventListener("command", () => this.removeItem());
+  }
+
+  get selectedItem() {
+    return this.items[this.richlistbox.selectedIndex];
+  }
+
+  setButtonState() {
+    let { upButton, downButton, removeButton } = this;
+    let { selectedIndex, itemCount } = this.richlistbox;
+    upButton.disabled = selectedIndex <= 0;
+    downButton.disabled = selectedIndex == itemCount - 1;
+    removeButton.disabled = itemCount <= 1 || !this.selectedItem.canRemove;
+  }
+
+  moveUp() {
+    let { selectedIndex } = this.richlistbox;
+    if (selectedIndex == 0) {
+      return;
+    }
+    let { items } = this;
+    let selectedItem = items[selectedIndex];
+    let prevItem = items[selectedIndex - 1];
+    items[selectedIndex - 1] = items[selectedIndex];
+    items[selectedIndex] = prevItem;
+    let prevEl = document.getElementById(prevItem.id);
+    let selectedEl = document.getElementById(selectedItem.id);
+    this.richlistbox.insertBefore(selectedEl, prevEl);
+    this.richlistbox.ensureElementIsVisible(selectedEl);
+    this.setButtonState();
+  }
+
+  moveDown() {
+    let { selectedIndex } = this.richlistbox;
+    if (selectedIndex == this.items.length - 1) {
+      return;
+    }
+    let { items } = this;
+    let selectedItem = items[selectedIndex];
+    let nextItem = items[selectedIndex + 1];
+    items[selectedIndex + 1] = items[selectedIndex];
+    items[selectedIndex] = nextItem;
+    let nextEl = document.getElementById(nextItem.id);
+    let selectedEl = document.getElementById(selectedItem.id);
+    this.richlistbox.insertBefore(nextEl, selectedEl);
+    this.richlistbox.ensureElementIsVisible(selectedEl);
+    this.setButtonState();
+  }
+
+  removeItem() {
+    let { selectedIndex } = this.richlistbox;
+
+    if (selectedIndex == -1) {
+      return;
+    }
+
+    let [item] = this.items.splice(selectedIndex, 1);
+    this.richlistbox.selectedItem.remove();
+    this.richlistbox.selectedIndex = Math.min(
+      selectedIndex,
+      this.richlistbox.itemCount - 1
+    );
+    this.richlistbox.ensureElementIsVisible(this.richlistbox.selectedItem);
+    this.onRemove(item);
+  }
+
+  setItems(items) {
+    this.items = items;
+    this.populate();
+    this.setButtonState();
+  }
+
+  /**
+   * Add an item to the top of the ordered list.
+   *
+   * @param {object} item The item to insert.
+   */
+  addItem(item) {
+    this.items.unshift(item);
+    this.richlistbox.insertBefore(
+      this.createItem(item),
+      this.richlistbox.firstElementChild
+    );
+    this.richlistbox.selectedIndex = 0;
+    this.richlistbox.ensureElementIsVisible(this.richlistbox.selectedItem);
+  }
+
+  populate() {
+    this.richlistbox.textContent = "";
+
+    let frag = document.createDocumentFragment();
+    for (let item of this.items) {
+      frag.appendChild(this.createItem(item));
+    }
+    this.richlistbox.appendChild(frag);
+
+    this.richlistbox.selectedIndex = 0;
+    this.richlistbox.ensureElementIsVisible(this.richlistbox.selectedItem);
+  }
+
+  createItem({ id, label, value }) {
+    let listitem = document.createXULElement("richlistitem");
+    listitem.id = id;
+    listitem.setAttribute("value", value);
+
+    let labelEl = document.createXULElement("label");
+    labelEl.textContent = label;
+    listitem.appendChild(labelEl);
+
+    return listitem;
+  }
+}
+
+/**
+ * The sorted select list of Locales available for the app.
+ */
+class SortedItemSelectList {
+  constructor({ menulist, button, onSelect, onChange, compareFn }) {
+    /** @type {XULElement} */
+    this.menulist = menulist;
+
+    /** @type {XULElement} */
+    this.popup = menulist.menupopup;
+
+    /** @type {XULElement} */
+    this.button = button;
+
+    /** @type {(a: LocaleDisplayInfo, b: LocaleDisplayInfo) => number} */
+    this.compareFn = compareFn;
+
+    /** @type {Array<LocaleDisplayInfo>} */
+    this.items = [];
+
+    menulist.addEventListener("command", () => {
+      button.disabled = !menulist.selectedItem;
+      if (menulist.selectedItem) {
+        onChange(this.items[menulist.selectedIndex]);
+      }
+    });
+    button.addEventListener("command", () => {
+      if (!menulist.selectedItem) {
+        return;
+      }
+
+      let [item] = this.items.splice(menulist.selectedIndex, 1);
+      menulist.selectedItem.remove();
+      menulist.setAttribute("label", menulist.getAttribute("placeholder"));
+      button.disabled = true;
+      menulist.disabled = menulist.itemCount == 0;
+      menulist.selectedIndex = -1;
+
+      onSelect(item);
+    });
+  }
+
+  /**
+   * @param {Array<LocaleDisplayInfo>} items
+   */
+  setItems(items) {
+    this.items = items.sort(this.compareFn);
+    this.populate();
+  }
+
+  populate() {
+    let { button, items, menulist, popup } = this;
+    popup.textContent = "";
+
+    let frag = document.createDocumentFragment();
+    for (let item of items) {
+      frag.appendChild(this.createItem(item));
+    }
+    popup.appendChild(frag);
+
+    menulist.setAttribute("label", menulist.getAttribute("placeholder"));
+    menulist.disabled = menulist.itemCount == 0;
+    menulist.selectedIndex = -1;
+    button.disabled = true;
+  }
+
+  /**
+   * Add an item to the list sorted by the label.
+   *
+   * @param {object} item The item to insert.
+   */
+  addItem(item) {
+    let { compareFn, items, menulist, popup } = this;
+
+    // Find the index of the item to insert before.
+    let i = items.findIndex(el => compareFn(el, item) >= 0);
+    items.splice(i, 0, item);
+    popup.insertBefore(this.createItem(item), menulist.getItemAtIndex(i));
+    menulist.disabled = menulist.itemCount == 0;
+  }
+
+  createItem({ label, value, className, disabled }) {
+    let item = document.createXULElement("menuitem");
+    item.setAttribute("label", label);
+    if (value) {
+      item.value = value;
+    }
+    if (className) {
+      item.classList.add(className);
+    }
+    if (disabled) {
+      item.setAttribute("disabled", "true");
+    }
+    return item;
+  }
+
+  /**
+   * Disable the inputs and set a data-l10n-id on the menulist. This can be
+   * reverted with `enableWithMessageId()`.
+   */
+  disableWithMessageId(messageId) {
+    this.menulist.setAttribute("data-l10n-id", messageId);
+    this.menulist.setAttribute(
+      "image",
+      "chrome://global/skin/icons/loading.png"
+    );
+    this.menulist.disabled = true;
+    this.button.disabled = true;
+  }
+
+  /**
+   * Enable the inputs and set a data-l10n-id on the menulist. This can be
+   * reverted with `disableWithMessageId()`.
+   */
+  enableWithMessageId(messageId) {
+    this.menulist.setAttribute("data-l10n-id", messageId);
+    this.menulist.removeAttribute("image");
+    this.menulist.disabled = this.menulist.itemCount == 0;
+    this.button.disabled = !this.menulist.selectedItem;
+  }
+}
+
+/**
+ * @typedef LocaleDisplayInfo
+ * @type {object}
+ * @property {string} id - A unique ID.
+ * @property {string} label - The localized display name.
+ * @property {string} value - The BCP 47 locale identifier or the word "search".
+ * @property {boolean} canRemove - Locales that are part of the packaged locales cannot be
+ *                             removed.
+ * @property {boolean} installed - Whether or not the locale is installed.
+ */
+
+/**
+ * @param {Array<string>} localeCodes - List of BCP 47 locale identifiers.
+ * @returns {Array<LocaleDisplayInfo>}
+ */
+async function getLocaleDisplayInfo(localeCodes) {
+  let availableLocales = new Set(await getAvailableLocales());
+  let packagedLocales = new Set(Services.locale.packagedLocales);
+  let localeNames = Services.intl.getLocaleDisplayNames(
+    undefined,
+    localeCodes,
+    { preferNative: true }
+  );
+  return localeCodes.map((code, i) => {
+    return {
+      id: "locale-" + code,
+      label: localeNames[i],
+      value: code,
+      canRemove: !packagedLocales.has(code),
+      installed: availableLocales.has(code),
+    };
+  });
+}
+
+/**
+ * @param {LocaleDisplayInfo} a
+ * @param {LocaleDisplayInfo} b
+ * @returns {number}
+ */
+function compareItems(a, b) {
+  // Sort by installed.
+  if (a.installed != b.installed) {
+    return a.installed ? -1 : 1;
+
+    // The search label is always last.
+  } else if (a.value == "search") {
+    return 1;
+  } else if (b.value == "search") {
+    return -1;
+
+    // If both items are locales, sort by label.
+  } else if (a.value && b.value) {
+    return a.label.localeCompare(b.label);
+
+    // One of them is a label, put it first.
+  } else if (a.value) {
+    return 1;
+  }
+  return -1;
+}
+
+var gMessengerLanguagesDialog = {
+  /**
+   * The publicly readable list of selected locales. It is only set when the dialog is
+   * accepted, and can be retrieved elsewhere by directly reading the property
+   * on gMessengerLanguagesDialog.
+   *
+   *   let { selected } = gMessengerLanguagesDialog;
+   *
+   * @type {null | Array<string>}
+   */
+  selected: null,
+
+  /**
+   * @type {SortedItemSelectList}
+   */
+  _availableLocalesUI: null,
+
+  /**
+   * @type {OrderedListBox}
+   */
+  _selectedLocalesUI: null,
+
+  get downloadEnabled() {
+    // Downloading langpacks isn't always supported, check the pref.
+    return Services.prefs.getBoolPref("intl.multilingual.downloadEnabled");
+  },
+
+  async onLoad() {
+    /**
+     * @typedef {object} Options - Options passed in to configure the subdialog.
+     * @property {Array<string>} [selectedLocalesForRestart] The optional list of
+     *   previously selected locales for when a restart is required. This list is
+     *   preserved between openings of the dialog.
+     * @property {boolean} search Whether the user opened this from "Search for more
+     *   languages" option.
+     */
+
+    /** @type {Options} */
+    let { selectedLocalesForRestart, search } = window.arguments[0];
+
+    // This is a list of available locales that the user selected. It's more
+    // restricted than the Intl notion of `requested` as it only contains
+    // locale codes for which we have matching locales available.
+    // The first time this dialog is opened, populate with appLocalesAsBCP47.
+    let selectedLocales =
+      selectedLocalesForRestart || Services.locale.appLocalesAsBCP47;
+    let selectedLocaleSet = new Set(selectedLocales);
+    let available = await getAvailableLocales();
+    let availableSet = new Set(available);
+
+    // Filter selectedLocales since the user may select a locale when it is
+    // available and then disable it.
+    selectedLocales = selectedLocales.filter(locale =>
+      availableSet.has(locale)
+    );
+    // Nothing in available should be in selectedSet.
+    available = available.filter(locale => !selectedLocaleSet.has(locale));
+
+    await this.initSelectedLocales(selectedLocales);
+    await this.initAvailableLocales(available, search);
+
+    this.initialized = true;
+
+    // Now the component is initialized, it's safe to accept the results.
+    document
+      .getElementById("MessengerLanguagesDialog")
+      .addEventListener("beforeaccept", () => {
+        this.selected = this._selectedLocalesUI.items.map(item => item.value);
+      });
+  },
+
+  /**
+   * @param {string[]} selectedLocales - BCP 47 locale identifiers
+   */
+  async initSelectedLocales(selectedLocales) {
+    this._selectedLocalesUI = new OrderedListBox({
+      richlistbox: document.getElementById("selectedLocales"),
+      upButton: document.getElementById("up"),
+      downButton: document.getElementById("down"),
+      removeButton: document.getElementById("remove"),
+      onRemove: item => this.selectedLocaleRemoved(item),
+    });
+    this._selectedLocalesUI.setItems(
+      await getLocaleDisplayInfo(selectedLocales)
+    );
+  },
+
+  /**
+   * @param {Set<string>} available - The set of available BCP 47 locale identifiers.
+   * @param {boolean} search - Whether the user opened this from "Search for more
+   *                           languages" option.
+   */
+  async initAvailableLocales(available, search) {
+    this._availableLocalesUI = new SortedItemSelectList({
+      menulist: document.getElementById("availableLocales"),
+      button: document.getElementById("add"),
+      compareFn: compareItems,
+      onSelect: item => this.availableLanguageSelected(item),
+      onChange: item => {
+        this.hideError();
+        if (item.value == "search") {
+          this.loadLocalesFromAMO();
+        }
+      },
+    });
+
+    // Populate the list with the installed locales even if the user is
+    // searching in case the download fails.
+    await this.loadLocalesFromInstalled(available);
+
+    // If the user opened this from the "Search for more languages" option,
+    // search AMO for available locales.
+    if (search) {
+      return this.loadLocalesFromAMO();
+    }
+
+    return undefined;
+  },
+
+  async loadLocalesFromAMO() {
+    if (!this.downloadEnabled) {
+      return;
+    }
+
+    // Disable the dropdown while we hit the network.
+    this._availableLocalesUI.disableWithMessageId(
+      "messenger-languages-searching"
+    );
+
+    // Fetch the available langpacks from AMO.
+    let availableLangpacks;
+    try {
+      availableLangpacks = await AddonRepository.getAvailableLangpacks();
+    } catch (e) {
+      this.showError();
+      return;
+    }
+
+    // Store the available langpack info for later use.
+    this.availableLangpacks = new Map();
+    for (let { target_locale, url, hash } of availableLangpacks) {
+      this.availableLangpacks.set(target_locale, { url, hash });
+    }
+
+    // Remove the installed locales from the available ones.
+    let installedLocales = new Set(await getAvailableLocales());
+    let notInstalledLocales = availableLangpacks
+      .filter(({ target_locale }) => !installedLocales.has(target_locale))
+      .map(lang => lang.target_locale);
+
+    // Create the rows for the remote locales.
+    let availableItems = await getLocaleDisplayInfo(notInstalledLocales);
+    availableItems.push({
+      label: await document.l10n.formatValue(
+        "messenger-languages-available-label"
+      ),
+      className: "label-item",
+      disabled: true,
+      installed: false,
+    });
+
+    // Remove the search option and add the remote locales.
+    let items = this._availableLocalesUI.items;
+    items.pop();
+    items = items.concat(availableItems);
+
+    // Update the dropdown and enable it again.
+    this._availableLocalesUI.setItems(items);
+    this._availableLocalesUI.enableWithMessageId(
+      "messenger-languages-select-language"
+    );
+  },
+
+  /**
+   * @param {Set<string>} available - The set of available (BCP 47) locales.
+   */
+  async loadLocalesFromInstalled(available) {
+    let items;
+    if (available.length > 0) {
+      items = await getLocaleDisplayInfo(available);
+      items.push(await this.createInstalledLabel());
+    } else {
+      items = [];
+    }
+    if (this.downloadEnabled) {
+      items.push({
+        label: await document.l10n.formatValue("messenger-languages-search"),
+        value: "search",
+      });
+    }
+    this._availableLocalesUI.setItems(items);
+  },
+
+  /**
+   * @param {LocaleDisplayInfo} item
+   */
+  async availableLanguageSelected(item) {
+    if ((await getAvailableLocales()).includes(item.value)) {
+      await this.requestLocalLanguage(item);
+    } else if (this.availableLangpacks.has(item.value)) {
+      await this.requestRemoteLanguage(item);
+    } else {
+      this.showError();
+    }
+  },
+
+  /**
+   * @param {LocaleDisplayInfo} item
+   */
+  async requestLocalLanguage(item) {
+    this._selectedLocalesUI.addItem(item);
+    let selectedCount = this._selectedLocalesUI.items.length;
+    let availableCount = (await getAvailableLocales()).length;
+    if (selectedCount == availableCount) {
+      // Remove the installed label, they're all installed.
+      this._availableLocalesUI.items.shift();
+      this._availableLocalesUI.setItems(this._availableLocalesUI.items);
+    }
+
+    // The label isn't always reset when the selected item is removed, so set it again.
+    this._availableLocalesUI.enableWithMessageId(
+      "messenger-languages-select-language"
+    );
+  },
+
+  /**
+   * @param {LocaleDisplayInfo} item
+   */
+  async requestRemoteLanguage(item) {
+    this._availableLocalesUI.disableWithMessageId(
+      "messenger-languages-downloading"
+    );
+
+    let { url, hash } = this.availableLangpacks.get(item.value);
+    let addon;
+
+    try {
+      addon = await AddonManager.getInstallForURL(url, { hash });
+      await addon.install();
+    } catch (e) {
+      this.showError();
+      return;
+    }
+
+    // If the add-on was previously installed, it might be disabled still.
+    if (addon.userDisabled) {
+      await addon.enable();
+    }
+
+    item.installed = true;
+    this._selectedLocalesUI.addItem(item);
+    this._availableLocalesUI.enableWithMessageId(
+      "messenger-languages-select-language"
+    );
+  },
+
+  showError() {
+    document.getElementById("warning-message").hidden = false;
+    this._availableLocalesUI.enableWithMessageId(
+      "messenger-languages-select-language"
+    );
+
+    // The height has likely changed, find our SubDialog and tell it to resize.
+    requestAnimationFrame(() => {
+      let dialogs = window.opener.gSubDialog._dialogs;
+      let index = dialogs.findIndex(d => d._frame.contentDocument == document);
+      if (index != -1) {
+        dialogs[index].resizeDialog();
+      }
+    });
+  },
+
+  hideError() {
+    document.getElementById("warning-message").hidden = true;
+  },
+
+  /**
+   * @param {LocaleDisplayInfo} item
+   */
+  async selectedLocaleRemoved(item) {
+    this._availableLocalesUI.addItem(item);
+
+    // If the item we added is at the top of the list, it needs the label.
+    if (this._availableLocalesUI.items[0] == item) {
+      this._availableLocalesUI.addItem(await this.createInstalledLabel());
+    }
+  },
+
+  async createInstalledLabel() {
+    return {
+      label: await document.l10n.formatValue(
+        "messenger-languages-installed-label"
+      ),
+      className: "label-item",
+      disabled: true,
+      installed: true,
+    };
+  },
+};
diff --git a/comm/mail/components/preferences/messengerLanguages.xhtml b/comm/mail/components/preferences/messengerLanguages.xhtml
new file mode 100644
index 0000000000..116ee4e5b2
--- /dev/null
+++ b/comm/mail/components/preferences/messengerLanguages.xhtml
@@ -0,0 +1,93 @@
+<?xml version="1.0"?>
+
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+
+<window
+  type="child"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  data-l10n-id="messenger-languages-window2"
+  onload="gMessengerLanguagesDialog.onLoad();"
+>
+  <dialog id="MessengerLanguagesDialog" buttons="accept,cancel">
+    <linkset>
+      <html:link rel="localization" href="branding/brand.ftl" />
+      <html:link
+        rel="localization"
+        href="messenger/preferences/languages.ftl"
+      />
+    </linkset>
+
+    <script src="chrome://global/content/preferencesBindings.js" />
+    <script src="chrome://messenger/content/preferences/messengerLanguages.js" />
+
+    <vbox
+      id="messengerLanguagesDialogPane"
+      class="prefpane largeDialogContainer"
+      flex="1"
+    >
+      <description data-l10n-id="messenger-languages-description" />
+      <hbox flex="1">
+        <vbox flex="1">
+          <richlistbox id="selectedLocales" flex="1" />
+          <menulist
+            id="availableLocales"
+            class="available-locales-list"
+            data-l10n-id="messenger-languages-select-language"
+            data-l10n-attrs="placeholder,label"
+          >
+            <menupopup />
+          </menulist>
+        </vbox>
+        <vbox>
+          <button
+            id="up"
+            class="action-button"
+            disabled="true"
+            data-l10n-id="languages-customize-moveup"
+          />
+          <button
+            id="down"
+            class="action-button"
+            disabled="true"
+            data-l10n-id="languages-customize-movedown"
+          />
+          <button
+            id="remove"
+            class="action-button"
+            disabled="true"
+            data-l10n-id="languages-customize-remove"
+          />
+          <vbox flex="1" pack="end">
+            <button
+              id="add"
+              class="add-messenger-language action-button"
+              data-l10n-id="languages-customize-add"
+              disabled="true"
+            />
+          </vbox>
+        </vbox>
+      </hbox>
+      <hbox
+        id="warning-message"
+        class="message-bar message-bar-warning"
+        hidden="true"
+      >
+        <html:img
+          class="message-bar-icon"
+          src="chrome://global/skin/icons/warning.svg"
+          alt=""
+        />
+        <description
+          class="message-bar-description"
+          data-l10n-id="messenger-languages-error"
+        />
+      </hbox>
+      <separator class="thin" />
+    </vbox>
+  </dialog>
+</window>
diff --git a/comm/mail/components/preferences/moz.build b/comm/mail/components/preferences/moz.build
new file mode 100644
index 0000000000..4eff028aeb
--- /dev/null
+++ b/comm/mail/components/preferences/moz.build
@@ -0,0 +1,18 @@
+# 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/.
+
+JAR_MANIFESTS += ["jar.mn"]
+
+DEFINES["MOZ_MACBUNDLE_NAME"] = CONFIG["MOZ_MACBUNDLE_NAME"]
+
+if CONFIG["MOZ_WIDGET_TOOLKIT"] in ("windows", "gtk", "cocoa"):
+    DEFINES["HAVE_SHELL_SERVICE"] = 1
+
+if CONFIG["MOZ_UPDATER"]:
+    DEFINES["MOZ_UPDATER"] = 1
+
+BROWSER_CHROME_MANIFESTS += [
+    "test/browser/browser.ini",
+]
diff --git a/comm/mail/components/preferences/notifications.js b/comm/mail/components/preferences/notifications.js
new file mode 100644
index 0000000000..0970a944bd
--- /dev/null
+++ b/comm/mail/components/preferences/notifications.js
@@ -0,0 +1,25 @@
+/* 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-globals-from ../../../../toolkit/content/preferencesBindings.js */
+
+Preferences.addAll([
+  { id: "mail.biff.alert.show_preview", type: "bool" },
+  { id: "mail.biff.alert.show_subject", type: "bool" },
+  { id: "mail.biff.alert.show_sender", type: "bool" },
+  { id: "alerts.totalOpenTime", type: "int" },
+]);
+
+var gNotificationsDialog = {
+  init() {
+    let element = document.getElementById("totalOpenTime");
+    Preferences.addSyncFromPrefListener(
+      element,
+      () => Preferences.get("alerts.totalOpenTime").value / 1000
+    );
+    Preferences.addSyncToPrefListener(element, element => element.value * 1000);
+  },
+};
+
+window.addEventListener("load", () => gNotificationsDialog.init());
diff --git a/comm/mail/components/preferences/notifications.xhtml b/comm/mail/components/preferences/notifications.xhtml
new file mode 100644
index 0000000000..d9abb47e4e
--- /dev/null
+++ b/comm/mail/components/preferences/notifications.xhtml
@@ -0,0 +1,71 @@
+<?xml version="1.0"?>
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+
+<!DOCTYPE window>
+
+<window
+  type="child"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  data-l10n-id="notifications-dialog-window"
+>
+  <dialog id="NotificationsDialog" dlgbuttons="accept,cancel">
+    <linkset>
+      <html:link
+        rel="localization"
+        href="messenger/preferences/notifications.ftl"
+      />
+    </linkset>
+    <description data-l10n-id="customize-alert-description" />
+
+    <checkbox
+      id="previewText"
+      class="indent"
+      data-l10n-id="preview-text-checkbox"
+      preference="mail.biff.alert.show_preview"
+    />
+    <checkbox
+      id="subject"
+      class="indent"
+      data-l10n-id="subject-checkbox"
+      preference="mail.biff.alert.show_subject"
+    />
+    <checkbox
+      id="sender"
+      class="indent"
+      data-l10n-id="sender-checkbox"
+      preference="mail.biff.alert.show_sender"
+    />
+
+    <separator />
+
+    <hbox align="center">
+      <label
+        id="totalOpenTimeBefore"
+        control="totalOpenTime"
+        data-l10n-id="open-time-label-before"
+      />
+      <html:input
+        id="totalOpenTime"
+        type="number"
+        class="size3"
+        min="1"
+        max="3600"
+        preference="alerts.totalOpenTime"
+      />
+      <label
+        id="totalOpenTimeEnd"
+        data-l10n-id="open-time-label-after"
+        class="startSpacing"
+      />
+    </hbox>
+    <separator />
+
+    <script src="chrome://global/content/preferencesBindings.js" />
+    <script src="chrome://messenger/content/preferences/notifications.js" />
+  </dialog>
+</window>
diff --git a/comm/mail/components/preferences/offline.js b/comm/mail/components/preferences/offline.js
new file mode 100644
index 0000000000..ae33950cf1
--- /dev/null
+++ b/comm/mail/components/preferences/offline.js
@@ -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/. */
+
+/* import-globals-from ../../../../toolkit/content/preferencesBindings.js */
+
+Preferences.addAll([
+  { id: "offline.autoDetect", type: "bool" },
+  { id: "offline.startup_state", type: "int" },
+  { id: "offline.send.unsent_messages", type: "int" },
+  { id: "offline.download.download_messages", type: "int" },
+]);
+
+var kAutomatic = 4;
+var kRememberLastState = 0;
+
+var gOfflineDialog = {
+  dialogSetup() {
+    let offlineAutoDetection = Preferences.get("offline.autoDetect");
+    let offlineStartupStatePref = Preferences.get("offline.startup_state");
+
+    offlineStartupStatePref.disabled = offlineAutoDetection.value;
+    if (offlineStartupStatePref.disabled) {
+      offlineStartupStatePref.value = kAutomatic;
+    } else if (offlineStartupStatePref.value == kAutomatic) {
+      offlineStartupStatePref.value = kRememberLastState;
+    }
+  },
+};
+
+Preferences.get("offline.autoDetect").on("change", gOfflineDialog.dialogSetup);
diff --git a/comm/mail/components/preferences/offline.xhtml b/comm/mail/components/preferences/offline.xhtml
new file mode 100644
index 0000000000..77a86cfa86
--- /dev/null
+++ b/comm/mail/components/preferences/offline.xhtml
@@ -0,0 +1,77 @@
+<?xml version="1.0"?>
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+
+<!DOCTYPE window>
+
+<window
+  type="child"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  onload="gOfflineDialog.dialogSetup();"
+  data-l10n-id="offline-dialog-window"
+>
+  <dialog id="OfflineSettingsDialog" dlgbuttons="accept,cancel">
+    <script src="chrome://global/content/preferencesBindings.js" />
+    <script src="chrome://messenger/content/preferences/offline.js" />
+
+    <linkset>
+      <html:link rel="localization" href="messenger/preferences/offline.ftl" />
+    </linkset>
+
+    <checkbox
+      data-l10n-id="autodetect-online-label"
+      preference="offline.autoDetect"
+    />
+
+    <separator class="thin" />
+
+    <label
+      data-l10n-id="offline-preference-startup-label"
+      control="whenStartingUp"
+    />
+    <radiogroup
+      id="whenStartingUp"
+      class="indent"
+      preference="offline.startup_state"
+    >
+      <radio value="0" data-l10n-id="status-radio-remember" />
+      <radio value="1" data-l10n-id="status-radio-ask" />
+      <radio value="2" data-l10n-id="status-radio-always-online" />
+      <radio value="3" data-l10n-id="status-radio-always-offline" />
+      <radio value="4" hidden="true" />
+    </radiogroup>
+
+    <separator />
+
+    <label data-l10n-id="going-online-label" control="whengoingOnlinestate" />
+    <radiogroup
+      id="whengoingOnlinestate"
+      orient="horizontal"
+      class="indent"
+      preference="offline.send.unsent_messages"
+    >
+      <radio value="1" data-l10n-id="going-online-auto" />
+      <radio value="2" data-l10n-id="going-online-not" />
+      <radio value="0" data-l10n-id="going-online-ask" />
+    </radiogroup>
+
+    <separator class="thin" />
+
+    <label data-l10n-id="going-offline-label" control="whengoingOfflinestate" />
+    <radiogroup
+      id="whengoingOfflinestate"
+      orient="horizontal"
+      class="indent"
+      preference="offline.download.download_messages"
+    >
+      <radio value="1" data-l10n-id="going-offline-auto" />
+      <radio value="2" data-l10n-id="going-offline-not" />
+      <radio value="0" data-l10n-id="going-offline-ask" />
+    </radiogroup>
+    <separator />
+  </dialog>
+</window>
diff --git a/comm/mail/components/preferences/passwordManager.js b/comm/mail/components/preferences/passwordManager.js
new file mode 100644
index 0000000000..67f08767d3
--- /dev/null
+++ b/comm/mail/components/preferences/passwordManager.js
@@ -0,0 +1,819 @@
+/* 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/. */
+
+/** * =================== SAVED SIGNONS CODE =================== */
+/* eslint-disable-next-line no-var */
+var { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+/* eslint-disable-next-line no-var */
+/* eslint-disable-next-line no-var */
+var { XPCOMUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/XPCOMUtils.sys.mjs"
+);
+
+ChromeUtils.defineESModuleGetters(this, {
+  DeferredTask: "resource://gre/modules/DeferredTask.sys.mjs",
+  OSKeyStore: "resource://gre/modules/OSKeyStore.sys.mjs",
+  PlacesUtils: "resource://gre/modules/PlacesUtils.sys.mjs",
+});
+
+// Default value for signon table sorting
+let lastSignonSortColumn = "origin";
+let lastSignonSortAscending = true;
+
+let showingPasswords = false;
+
+// password-manager lists
+let signons = [];
+let deletedSignons = [];
+
+// Elements that would be used frequently
+let filterField;
+let togglePasswordsButton;
+let signonsIntro;
+let removeButton;
+let removeAllButton;
+let signonsTree;
+
+let signonReloadDisplay = {
+  observe(subject, topic, data) {
+    if (topic == "passwordmgr-storage-changed") {
+      switch (data) {
+        case "addLogin":
+        case "modifyLogin":
+        case "removeLogin":
+        case "removeAllLogins":
+          if (!signonsTree) {
+            return;
+          }
+          signons.length = 0;
+          LoadSignons();
+          // apply the filter if needed
+          if (filterField && filterField.value != "") {
+            FilterPasswords();
+          }
+          signonsTree.ensureRowIsVisible(
+            signonsTree.view.selection.currentIndex
+          );
+          break;
+      }
+      Services.obs.notifyObservers(null, "passwordmgr-dialog-updated");
+    }
+  },
+};
+
+// Formatter for localization.
+let dateFormatter = new Services.intl.DateTimeFormat(undefined, {
+  dateStyle: "medium",
+});
+let dateAndTimeFormatter = new Services.intl.DateTimeFormat(undefined, {
+  dateStyle: "medium",
+  timeStyle: "short",
+});
+
+function Startup() {
+  // be prepared to reload the display if anything changes
+  Services.obs.addObserver(signonReloadDisplay, "passwordmgr-storage-changed");
+
+  signonsTree = document.getElementById("signonsTree");
+  filterField = document.getElementById("filter");
+  togglePasswordsButton = document.getElementById("togglePasswords");
+  signonsIntro = document.getElementById("signonsIntro");
+  removeButton = document.getElementById("removeSignon");
+  removeAllButton = document.getElementById("removeAllSignons");
+
+  document.l10n.setAttributes(togglePasswordsButton, "show-passwords");
+  document.l10n.setAttributes(signonsIntro, "logins-description-all");
+  document.l10n.setAttributes(removeAllButton, "remove-all");
+
+  document
+    .getElementsByTagName("treecols")[0]
+    .addEventListener("click", event => {
+      let { target, button } = event;
+      let sortField = target.getAttribute("data-field-name");
+
+      if (target.nodeName != "treecol" || button != 0 || !sortField) {
+        return;
+      }
+
+      SignonColumnSort(sortField);
+    });
+
+  LoadSignons();
+
+  // filter the table if requested by caller
+  if (
+    window.arguments &&
+    window.arguments[0] &&
+    window.arguments[0].filterString
+  ) {
+    setFilter(window.arguments[0].filterString);
+  }
+
+  FocusFilterBox();
+  document.l10n
+    .translateElements(document.querySelectorAll("[data-l10n-id]"))
+    .then(() => window.sizeToContent());
+}
+
+function Shutdown() {
+  Services.obs.removeObserver(
+    signonReloadDisplay,
+    "passwordmgr-storage-changed"
+  );
+}
+
+function setFilter(aFilterString) {
+  filterField.value = aFilterString;
+  FilterPasswords();
+}
+
+let signonsTreeView = {
+  QueryInterface: ChromeUtils.generateQI(["nsITreeView"]),
+  _filterSet: [],
+  _lastSelectedRanges: [],
+  selection: null,
+
+  rowCount: 0,
+  setTree(tree) {},
+  getImageSrc(row, column) {
+    if (column.element.getAttribute("id") !== "providerCol") {
+      return "";
+    }
+
+    const signon = GetVisibleLogins()[row];
+
+    return PlacesUtils.urlWithSizeRef(window, "page-icon:" + signon.origin, 16);
+  },
+  getCellValue(row, column) {},
+  getCellText(row, column) {
+    let time;
+    let signon = GetVisibleLogins()[row];
+    switch (column.id) {
+      case "providerCol":
+        return signon.httpRealm
+          ? signon.origin + " (" + signon.httpRealm + ")"
+          : signon.origin;
+      case "userCol":
+        return signon.username || "";
+      case "passwordCol":
+        return signon.password || "";
+      case "timeCreatedCol":
+        time = new Date(signon.timeCreated);
+        return dateFormatter.format(time);
+      case "timeLastUsedCol":
+        time = new Date(signon.timeLastUsed);
+        return dateAndTimeFormatter.format(time);
+      case "timePasswordChangedCol":
+        time = new Date(signon.timePasswordChanged);
+        return dateFormatter.format(time);
+      case "timesUsedCol":
+        return signon.timesUsed;
+      default:
+        return "";
+    }
+  },
+  isEditable(row, col) {
+    if (col.id == "userCol" || col.id == "passwordCol") {
+      return true;
+    }
+    return false;
+  },
+  isSeparator(index) {
+    return false;
+  },
+  isSorted() {
+    return false;
+  },
+  isContainer(index) {
+    return false;
+  },
+  cycleHeader(column) {},
+  getRowProperties(row) {
+    return "";
+  },
+  getColumnProperties(column) {
+    return "";
+  },
+  getCellProperties(row, column) {
+    if (column.element.getAttribute("id") == "providerCol") {
+      return "ltr";
+    }
+
+    return "";
+  },
+  setCellText(row, col, value) {
+    let table = GetVisibleLogins();
+    function _editLogin(field) {
+      if (value == table[row][field]) {
+        return;
+      }
+      let existingLogin = table[row].clone();
+      table[row][field] = value;
+      table[row].timePasswordChanged = Date.now();
+      Services.logins.modifyLogin(existingLogin, table[row]);
+      signonsTree.invalidateRow(row);
+    }
+
+    if (col.id == "userCol") {
+      _editLogin("username");
+    } else if (col.id == "passwordCol") {
+      if (!value) {
+        return;
+      }
+      _editLogin("password");
+    }
+  },
+};
+
+function SortTree(column, ascending) {
+  let table = GetVisibleLogins();
+  // remember which item was selected so we can restore it after the sort
+  let selections = GetTreeSelections();
+  let selectedNumber = selections.length ? table[selections[0]].number : -1;
+  function compareFunc(a, b) {
+    let valA, valB;
+    switch (column) {
+      case "origin":
+        let realmA = a.httpRealm;
+        let realmB = b.httpRealm;
+        realmA = realmA == null ? "" : realmA.toLowerCase();
+        realmB = realmB == null ? "" : realmB.toLowerCase();
+
+        valA = a[column].toLowerCase() + realmA;
+        valB = b[column].toLowerCase() + realmB;
+        break;
+      case "username":
+      case "password":
+        valA = a[column].toLowerCase();
+        valB = b[column].toLowerCase();
+        break;
+
+      default:
+        valA = a[column];
+        valB = b[column];
+    }
+
+    if (valA < valB) {
+      return -1;
+    }
+    if (valA > valB) {
+      return 1;
+    }
+    return 0;
+  }
+
+  // do the sort
+  table.sort(compareFunc);
+  if (!ascending) {
+    table.reverse();
+  }
+
+  // restore the selection
+  let selectedRow = -1;
+  if (selectedNumber >= 0 && false) {
+    for (let s = 0; s < table.length; s++) {
+      if (table[s].number == selectedNumber) {
+        // update selection
+        // note: we need to deselect before reselecting in order to trigger ...Selected()
+        signonsTree.view.selection.select(-1);
+        signonsTree.view.selection.select(s);
+        selectedRow = s;
+        break;
+      }
+    }
+  }
+
+  // display the results
+  signonsTree.invalidate();
+  if (selectedRow >= 0) {
+    signonsTree.ensureRowIsVisible(selectedRow);
+  }
+}
+
+function LoadSignons() {
+  // loads signons into table
+  try {
+    signons = Services.logins.getAllLogins();
+  } catch (e) {
+    signons = [];
+  }
+  signons.forEach(login => login.QueryInterface(Ci.nsILoginMetaInfo));
+  signonsTreeView.rowCount = signons.length;
+
+  // sort and display the table
+  signonsTree.view = signonsTreeView;
+  // The sort column didn't change. SortTree (called by
+  // SignonColumnSort) assumes we want to toggle the sort
+  // direction but here we don't so we have to trick it
+  lastSignonSortAscending = !lastSignonSortAscending;
+  SignonColumnSort(lastSignonSortColumn);
+
+  // disable "remove all signons" button if there are no signons
+  if (signons.length == 0) {
+    removeAllButton.setAttribute("disabled", "true");
+    togglePasswordsButton.setAttribute("disabled", "true");
+  } else {
+    removeAllButton.removeAttribute("disabled");
+    togglePasswordsButton.removeAttribute("disabled");
+  }
+
+  return true;
+}
+
+function GetVisibleLogins() {
+  return signonsTreeView._filterSet.length
+    ? signonsTreeView._filterSet
+    : signons;
+}
+
+function GetTreeSelections() {
+  let selections = [];
+  let select = signonsTree.view.selection;
+  if (select) {
+    let count = select.getRangeCount();
+    let min = {};
+    let max = {};
+    for (let i = 0; i < count; i++) {
+      select.getRangeAt(i, min, max);
+      for (let k = min.value; k <= max.value; k++) {
+        if (k != -1) {
+          selections[selections.length] = k;
+        }
+      }
+    }
+  }
+  return selections;
+}
+
+function SignonSelected() {
+  let selections = GetTreeSelections();
+  if (selections.length) {
+    removeButton.removeAttribute("disabled");
+  } else {
+    removeButton.setAttribute("disabled", true);
+  }
+}
+
+function DeleteSignon() {
+  let syncNeeded = signonsTreeView._filterSet.length != 0;
+  let tree = signonsTree;
+  let view = signonsTreeView;
+  let table = GetVisibleLogins();
+
+  // Turn off tree selection notifications during the deletion
+  tree.view.selection.selectEventsSuppressed = true;
+
+  // remove selected items from list (by setting them to null) and place in deleted list
+  let selections = GetTreeSelections();
+  for (let s = selections.length - 1; s >= 0; s--) {
+    let i = selections[s];
+    deletedSignons.push(table[i]);
+    table[i] = null;
+  }
+
+  // collapse list by removing all the null entries
+  for (let j = 0; j < table.length; j++) {
+    if (table[j] == null) {
+      let k = j;
+      while (k < table.length && table[k] == null) {
+        k++;
+      }
+      table.splice(j, k - j);
+      view.rowCount -= k - j;
+      tree.rowCountChanged(j, j - k);
+    }
+  }
+
+  // update selection and/or buttons
+  if (table.length) {
+    // update selection
+    let nextSelection =
+      selections[0] < table.length ? selections[0] : table.length - 1;
+    tree.view.selection.select(nextSelection);
+  } else {
+    // disable buttons
+    removeButton.setAttribute("disabled", "true");
+    removeAllButton.setAttribute("disabled", "true");
+  }
+  tree.view.selection.selectEventsSuppressed = false;
+  FinalizeSignonDeletions(syncNeeded);
+}
+
+async function DeleteAllSignons() {
+  // Confirm the user wants to remove all passwords
+  let dummy = { value: false };
+  let [title, message] = await document.l10n.formatValues([
+    { id: "remove-all-passwords-title" },
+    { id: "remove-all-passwords-prompt" },
+  ]);
+  if (
+    Services.prompt.confirmEx(
+      window,
+      title,
+      message,
+      Services.prompt.STD_YES_NO_BUTTONS + Services.prompt.BUTTON_POS_1_DEFAULT,
+      null,
+      null,
+      null,
+      null,
+      dummy
+    ) == 1
+  ) {
+    // 1 == "No" button
+    return;
+  }
+
+  let syncNeeded = signonsTreeView._filterSet.length != 0;
+  let view = signonsTreeView;
+  let table = GetVisibleLogins();
+
+  // remove all items from table and place in deleted table
+  for (let i = 0; i < table.length; i++) {
+    deletedSignons.push(table[i]);
+  }
+  table.length = 0;
+
+  // clear out selections
+  view.selection.select(-1);
+
+  // update the tree view and notify the tree
+  view.rowCount = 0;
+
+  signonsTree.rowCountChanged(0, -deletedSignons.length);
+  signonsTree.invalidate();
+
+  // disable buttons
+  removeButton.setAttribute("disabled", "true");
+  removeAllButton.setAttribute("disabled", "true");
+  FinalizeSignonDeletions(syncNeeded);
+}
+
+async function TogglePasswordVisible() {
+  if (showingPasswords || (await masterPasswordLogin(AskUserShowPasswords))) {
+    showingPasswords = !showingPasswords;
+    document.l10n.setAttributes(
+      togglePasswordsButton,
+      showingPasswords ? "hide-passwords" : "show-passwords"
+    );
+    document.getElementById("passwordCol").hidden = !showingPasswords;
+    FilterPasswords();
+  }
+
+  // Notify observers that the password visibility toggling is
+  // completed.  (Mostly useful for tests)
+  Services.obs.notifyObservers(null, "passwordmgr-password-toggle-complete");
+}
+
+async function AskUserShowPasswords() {
+  let dummy = { value: false };
+
+  // Confirm the user wants to display passwords
+  return (
+    Services.prompt.confirmEx(
+      window,
+      null,
+      await document.l10n.formatValue("no-master-password-prompt"),
+      Services.prompt.STD_YES_NO_BUTTONS,
+      null,
+      null,
+      null,
+      null,
+      dummy
+    ) == 0
+  ); // 0=="Yes" button
+}
+
+function FinalizeSignonDeletions(syncNeeded) {
+  for (let s = 0; s < deletedSignons.length; s++) {
+    Services.logins.removeLogin(deletedSignons[s]);
+  }
+  // If the deletion has been performed in a filtered view, reflect the deletion in the unfiltered table.
+  // See bug 405389.
+  if (syncNeeded) {
+    try {
+      signons = Services.logins.getAllLogins();
+    } catch (e) {
+      signons = [];
+    }
+  }
+  deletedSignons.length = 0;
+}
+
+function HandleSignonKeyPress(e) {
+  // If editing is currently performed, don't do anything.
+  if (signonsTree.getAttribute("editing")) {
+    return;
+  }
+  if (
+    e.keyCode == KeyboardEvent.DOM_VK_DELETE ||
+    (AppConstants.platform == "macosx" &&
+      e.keyCode == KeyboardEvent.DOM_VK_BACK_SPACE)
+  ) {
+    DeleteSignon();
+    e.preventDefault();
+  }
+}
+
+function getColumnByName(column) {
+  switch (column) {
+    case "origin":
+      return document.getElementById("providerCol");
+    case "username":
+      return document.getElementById("userCol");
+    case "password":
+      return document.getElementById("passwordCol");
+    case "timeCreated":
+      return document.getElementById("timeCreatedCol");
+    case "timeLastUsed":
+      return document.getElementById("timeLastUsedCol");
+    case "timePasswordChanged":
+      return document.getElementById("timePasswordChangedCol");
+    case "timesUsed":
+      return document.getElementById("timesUsedCol");
+  }
+  return undefined;
+}
+
+function SignonColumnSort(column) {
+  let sortedCol = getColumnByName(column);
+  let lastSortedCol = getColumnByName(lastSignonSortColumn);
+
+  // clear out the sortDirection attribute on the old column
+  lastSortedCol.removeAttribute("sortDirection");
+
+  // determine if sort is to be ascending or descending
+  lastSignonSortAscending =
+    column == lastSignonSortColumn ? !lastSignonSortAscending : true;
+
+  // sort
+  lastSignonSortColumn = column;
+  SortTree(lastSignonSortColumn, lastSignonSortAscending);
+
+  // set the sortDirection attribute to get the styling going
+  // first we need to get the right element
+  sortedCol.setAttribute(
+    "sortDirection",
+    lastSignonSortAscending ? "ascending" : "descending"
+  );
+}
+
+function SignonClearFilter() {
+  let singleSelection = signonsTreeView.selection.count == 1;
+
+  // Clear the Tree Display
+  signonsTreeView.rowCount = 0;
+  signonsTree.rowCountChanged(0, -signonsTreeView._filterSet.length);
+  signonsTreeView._filterSet = [];
+
+  // Just reload the list to make sure deletions are respected
+  LoadSignons();
+
+  // Restore selection
+  if (singleSelection) {
+    signonsTreeView.selection.clearSelection();
+    for (let i = 0; i < signonsTreeView._lastSelectedRanges.length; ++i) {
+      let range = signonsTreeView._lastSelectedRanges[i];
+      signonsTreeView.selection.rangedSelect(range.min, range.max, true);
+    }
+  } else {
+    signonsTreeView.selection.select(0);
+  }
+  signonsTreeView._lastSelectedRanges = [];
+
+  document.l10n.setAttributes(signonsIntro, "logins-description-all");
+  document.l10n.setAttributes(removeAllButton, "remove-all");
+}
+
+function FocusFilterBox() {
+  if (filterField.getAttribute("focused") != "true") {
+    filterField.focus();
+  }
+}
+
+function SignonMatchesFilter(aSignon, aFilterValue) {
+  if (aSignon.origin.toLowerCase().includes(aFilterValue)) {
+    return true;
+  }
+  if (
+    aSignon.username &&
+    aSignon.username.toLowerCase().includes(aFilterValue)
+  ) {
+    return true;
+  }
+  if (
+    aSignon.httpRealm &&
+    aSignon.httpRealm.toLowerCase().includes(aFilterValue)
+  ) {
+    return true;
+  }
+  if (
+    showingPasswords &&
+    aSignon.password &&
+    aSignon.password.toLowerCase().includes(aFilterValue)
+  ) {
+    return true;
+  }
+
+  return false;
+}
+
+function _filterPasswords(aFilterValue, view) {
+  aFilterValue = aFilterValue.toLowerCase();
+  return signons.filter(s => SignonMatchesFilter(s, aFilterValue));
+}
+
+function SignonSaveState() {
+  // Save selection
+  let seln = signonsTreeView.selection;
+  signonsTreeView._lastSelectedRanges = [];
+  let rangeCount = seln.getRangeCount();
+  for (let i = 0; i < rangeCount; ++i) {
+    let min = {};
+    let max = {};
+    seln.getRangeAt(i, min, max);
+    signonsTreeView._lastSelectedRanges.push({
+      min: min.value,
+      max: max.value,
+    });
+  }
+}
+
+function FilterPasswords() {
+  if (filterField.value == "") {
+    SignonClearFilter();
+    return;
+  }
+
+  let newFilterSet = _filterPasswords(filterField.value, signonsTreeView);
+  if (!signonsTreeView._filterSet.length) {
+    // Save Display Info for the Non-Filtered mode when we first
+    // enter Filtered mode.
+    SignonSaveState();
+  }
+  signonsTreeView._filterSet = newFilterSet;
+
+  // Clear the display
+  let oldRowCount = signonsTreeView.rowCount;
+  signonsTreeView.rowCount = 0;
+  signonsTree.rowCountChanged(0, -oldRowCount);
+  // Set up the filtered display
+  signonsTreeView.rowCount = signonsTreeView._filterSet.length;
+  signonsTree.rowCountChanged(0, signonsTreeView.rowCount);
+
+  // if the view is not empty then select the first item
+  if (signonsTreeView.rowCount > 0) {
+    signonsTreeView.selection.select(0);
+  }
+
+  document.l10n.setAttributes(signonsIntro, "logins-description-filtered");
+  document.l10n.setAttributes(removeAllButton, "remove-all-shown");
+}
+
+function CopyProviderUrl() {
+  // Copy selected provider url to clipboard
+  let clipboard = Cc["@mozilla.org/widget/clipboardhelper;1"].getService(
+    Ci.nsIClipboardHelper
+  );
+  let row = signonsTree.currentIndex;
+  let url = signonsTreeView.getCellText(row, { id: "providerCol" });
+  clipboard.copyString(url);
+}
+
+async function CopyPassword() {
+  // Don't copy passwords if we aren't already showing the passwords & a master
+  // password hasn't been entered.
+  if (!showingPasswords && !(await masterPasswordLogin())) {
+    return;
+  }
+  // Copy selected signon's password to clipboard
+  let clipboard = Cc["@mozilla.org/widget/clipboardhelper;1"].getService(
+    Ci.nsIClipboardHelper
+  );
+  let row = signonsTree.currentIndex;
+  let password = signonsTreeView.getCellText(row, { id: "passwordCol" });
+  clipboard.copyString(password);
+}
+
+function CopyUsername() {
+  // Copy selected signon's username to clipboard
+  let clipboard = Cc["@mozilla.org/widget/clipboardhelper;1"].getService(
+    Ci.nsIClipboardHelper
+  );
+  let row = signonsTree.currentIndex;
+  let username = signonsTreeView.getCellText(row, { id: "userCol" });
+  clipboard.copyString(username);
+}
+
+function EditCellInSelectedRow(columnName) {
+  let row = signonsTree.currentIndex;
+  let columnElement = getColumnByName(columnName);
+  signonsTree.startEditing(
+    row,
+    signonsTree.columns.getColumnFor(columnElement)
+  );
+}
+
+function UpdateContextMenu() {
+  let singleSelection = signonsTreeView.selection.count == 1;
+  let menuItems = new Map();
+  let menupopup = document.getElementById("signonsTreeContextMenu");
+  for (let menuItem of menupopup.querySelectorAll("menuitem")) {
+    menuItems.set(menuItem.id, menuItem);
+  }
+
+  if (!singleSelection) {
+    for (let menuItem of menuItems.values()) {
+      menuItem.setAttribute("disabled", "true");
+    }
+    return;
+  }
+
+  let selectedRow = signonsTree.currentIndex;
+
+  // Disable "Copy Username" if the username is empty.
+  if (signonsTreeView.getCellText(selectedRow, { id: "userCol" }) != "") {
+    menuItems.get("context-copyusername").removeAttribute("disabled");
+  } else {
+    menuItems.get("context-copyusername").setAttribute("disabled", "true");
+  }
+
+  menuItems.get("context-copyproviderurl").removeAttribute("disabled");
+  menuItems.get("context-editusername").removeAttribute("disabled");
+  menuItems.get("context-copypassword").removeAttribute("disabled");
+
+  // Disable "Edit Password" if the password column isn't showing.
+  if (!document.getElementById("passwordCol").hidden) {
+    menuItems.get("context-editpassword").removeAttribute("disabled");
+  } else {
+    menuItems.get("context-editpassword").setAttribute("disabled", "true");
+  }
+}
+
+async function masterPasswordLogin(noPasswordCallback) {
+  // This doesn't harm if passwords are not encrypted
+  let tokendb = Cc["@mozilla.org/security/pk11tokendb;1"].createInstance(
+    Ci.nsIPK11TokenDB
+  );
+  let token = tokendb.getInternalKeyToken();
+
+  // If there is no primary password, still give the user a chance to opt-out of displaying passwords
+  if (token.checkPassword("")) {
+    // The OS re-authentication on Linux isn't working (Bug 1527745),
+    // still add the confirm dialog for Linux.
+    if (
+      Services.prefs.getBoolPref("signon.management.page.os-auth.enabled") &&
+      AppConstants.platform !== "linux"
+    ) {
+      // Require OS authentication before the user can show the passwords or copy them.
+      let messageId = "password-os-auth-dialog-message";
+      if (AppConstants.platform == "macosx") {
+        // MacOS requires a special format of this dialog string.
+        // See preferences.ftl for more information.
+        messageId += "-macosx";
+      }
+      let [messageText, captionText] = await document.l10n.formatMessages([
+        {
+          id: messageId,
+        },
+        {
+          id: "password-os-auth-dialog-caption",
+        },
+      ]);
+      let win = Services.wm.getMostRecentWindow("");
+      let loggedIn = await OSKeyStore.ensureLoggedIn(
+        messageText.value,
+        captionText.value,
+        win,
+        false
+      );
+      if (!loggedIn.authenticated) {
+        return false;
+      }
+      return true;
+    }
+    return noPasswordCallback ? noPasswordCallback() : true;
+  }
+
+  // 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.
+  }
+
+  return token.isLoggedIn();
+}
+
+function escapeKeyHandler() {
+  // If editing is currently performed, don't do anything.
+  if (signonsTree.getAttribute("editing")) {
+    return;
+  }
+  window.close();
+}
diff --git a/comm/mail/components/preferences/passwordManager.xhtml b/comm/mail/components/preferences/passwordManager.xhtml
new file mode 100644
index 0000000000..594f2da8d8
--- /dev/null
+++ b/comm/mail/components/preferences/passwordManager.xhtml
@@ -0,0 +1,186 @@
+<?xml version="1.0"?>
+<!-- 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 https://mozilla.org/MPL/2.0/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+<?xml-stylesheet href="chrome://messenger/skin/shared/preferences/passwordmgr.css"?>
+
+<window
+  id="SignonViewerDialog"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  onload="Startup();"
+  onunload="Shutdown();"
+  data-l10n-id="saved-logins"
+  persist="width height"
+>
+  <linkset>
+    <html:link rel="localization" href="branding/brand.ftl" />
+    <html:link
+      rel="localization"
+      href="messenger/preferences/passwordManager.ftl"
+    />
+  </linkset>
+  <script src="chrome://messenger/content/globalOverlay.js" />
+  <script src="chrome://global/content/editMenuOverlay.js" />
+  <script src="chrome://messenger/content/preferences/passwordManager.js" />
+
+  <keyset>
+    <key keycode="VK_ESCAPE" oncommand="escapeKeyHandler();" />
+    <key
+      data-l10n-id="window-close"
+      modifiers="accel"
+      oncommand="escapeKeyHandler();"
+    />
+    <key
+      data-l10n-id="focus-search-primary-shortcut"
+      modifiers="accel"
+      oncommand="FocusFilterBox();"
+    />
+    <key
+      data-l10n-id="focus-search-alt-shortcut"
+      modifiers="accel"
+      oncommand="FocusFilterBox();"
+    />
+  </keyset>
+
+  <popupset id="signonsTreeContextSet">
+    <menupopup id="signonsTreeContextMenu" onpopupshowing="UpdateContextMenu()">
+      <menuitem
+        id="context-copyproviderurl"
+        data-l10n-id="copy-provider-url-cmd"
+        oncommand="CopyProviderUrl()"
+      />
+      <menuseparator />
+      <menuitem
+        id="context-copyusername"
+        data-l10n-id="copy-username-cmd"
+        oncommand="CopyUsername()"
+      />
+      <menuitem
+        id="context-editusername"
+        data-l10n-id="edit-username-cmd"
+        oncommand="EditCellInSelectedRow('username')"
+      />
+      <menuseparator />
+      <menuitem
+        id="context-copypassword"
+        data-l10n-id="copy-password-cmd"
+        oncommand="CopyPassword()"
+      />
+      <menuitem
+        id="context-editpassword"
+        data-l10n-id="edit-password-cmd"
+        oncommand="EditCellInSelectedRow('password')"
+      />
+    </menupopup>
+  </popupset>
+
+  <!-- saved signons -->
+  <vbox id="savedsignons" class="contentPane" flex="1">
+    <!-- filter -->
+    <hbox align="center">
+      <search-textbox
+        id="filter"
+        flex="1"
+        aria-controls="signonsTree"
+        oncommand="FilterPasswords();"
+        data-l10n-id="search-filter"
+      />
+    </hbox>
+
+    <label control="signonsTree" id="signonsIntro" />
+    <separator class="thin" />
+    <tree
+      id="signonsTree"
+      flex="1"
+      onkeypress="HandleSignonKeyPress(event)"
+      onselect="SignonSelected();"
+      editable="true"
+      context="signonsTreeContextMenu"
+    >
+      <treecols>
+        <treecol
+          id="providerCol"
+          data-l10n-id="column-heading-provider"
+          data-field-name="origin"
+          persist="width"
+          ignoreincolumnpicker="true"
+          sortDirection="ascending"
+        />
+        <splitter class="tree-splitter" />
+        <treecol
+          id="userCol"
+          data-l10n-id="column-heading-username"
+          ignoreincolumnpicker="true"
+          data-field-name="username"
+          persist="width"
+        />
+        <splitter class="tree-splitter" />
+        <treecol
+          id="passwordCol"
+          data-l10n-id="column-heading-password"
+          ignoreincolumnpicker="true"
+          data-field-name="password"
+          persist="width"
+          hidden="true"
+        />
+        <splitter class="tree-splitter" />
+        <treecol
+          id="timeCreatedCol"
+          data-l10n-id="column-heading-time-created"
+          data-field-name="timeCreated"
+          persist="width hidden"
+          hidden="true"
+        />
+        <splitter class="tree-splitter" />
+        <treecol
+          id="timeLastUsedCol"
+          data-l10n-id="column-heading-time-last-used"
+          data-field-name="timeLastUsed"
+          persist="width hidden"
+          hidden="true"
+        />
+        <splitter class="tree-splitter" />
+        <treecol
+          id="timePasswordChangedCol"
+          data-l10n-id="column-heading-time-password-changed"
+          data-field-name="timePasswordChanged"
+          persist="width hidden"
+        />
+        <splitter class="tree-splitter" />
+        <treecol
+          id="timesUsedCol"
+          data-l10n-id="column-heading-times-used"
+          data-field-name="timesUsed"
+          persist="width hidden"
+          hidden="true"
+        />
+        <splitter class="tree-splitter" />
+      </treecols>
+      <treechildren />
+    </tree>
+    <separator class="thin" />
+    <hbox id="SignonViewerButtons">
+      <button
+        id="removeSignon"
+        disabled="true"
+        data-l10n-id="remove"
+        oncommand="DeleteSignon();"
+      />
+      <button id="removeAllSignons" oncommand="DeleteAllSignons();" />
+      <spacer flex="1" />
+      <button id="togglePasswords" oncommand="TogglePasswordVisible();" />
+    </hbox>
+  </vbox>
+  <hbox align="end">
+    <hbox class="actionButtons" flex="1">
+      <spacer flex="1" />
+      <button
+        oncommand="window.close();"
+        data-l10n-id="password-close-button"
+      />
+    </hbox>
+  </hbox>
+</window>
diff --git a/comm/mail/components/preferences/permissions.js b/comm/mail/components/preferences/permissions.js
new file mode 100644
index 0000000000..3a75bc0ec6
--- /dev/null
+++ b/comm/mail/components/preferences/permissions.js
@@ -0,0 +1,501 @@
+/* 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/content/treeUtils.js
+/* globals gTreeUtils */
+
+var { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+
+var NOTIFICATION_FLUSH_PERMISSIONS = "flush-pending-permissions";
+
+/**
+ * Magic URI base used so the permission manager can store
+ * remote content permissions for a given email address.
+ */
+var MAILURI_BASE = "chrome://messenger/content/email=";
+
+function Permission(principal, type, capability) {
+  this.principal = principal;
+  this.origin = principal.origin;
+  this.type = type;
+  this.capability = capability;
+}
+
+var gPermissionManager = {
+  _type: "",
+  _permissions: [],
+  _permissionsToAdd: new Map(),
+  _permissionsToDelete: new Map(),
+  _tree: null,
+  _observerRemoved: false,
+
+  _view: {
+    QueryInterface: ChromeUtils.generateQI(["nsITreeView"]),
+    _rowCount: 0,
+    get rowCount() {
+      return this._rowCount;
+    },
+    getCellText(aRow, aColumn) {
+      if (aColumn.id == "siteCol") {
+        return gPermissionManager._permissions[aRow].origin.replace(
+          MAILURI_BASE,
+          ""
+        );
+      } else if (aColumn.id == "statusCol") {
+        return gPermissionManager._permissions[aRow].capability;
+      }
+      return "";
+    },
+
+    isSeparator(aIndex) {
+      return false;
+    },
+    isSorted() {
+      return false;
+    },
+    isContainer(aIndex) {
+      return false;
+    },
+    setTree(aTree) {},
+    getImageSrc(aRow, aColumn) {},
+    getProgressMode(aRow, aColumn) {},
+    getCellValue(aRow, aColumn) {},
+    cycleHeader(column) {},
+    getRowProperties(row) {
+      return "";
+    },
+    getColumnProperties(column) {
+      return "";
+    },
+    getCellProperties(row, column) {
+      if (column.element.getAttribute("id") == "siteCol") {
+        return "ltr";
+      }
+      return "";
+    },
+  },
+
+  async _getCapabilityString(aCapability) {
+    var stringKey = null;
+    switch (aCapability) {
+      case Ci.nsIPermissionManager.ALLOW_ACTION:
+        stringKey = "permission-can-label";
+        break;
+      case Ci.nsIPermissionManager.DENY_ACTION:
+        stringKey = "permission-cannot-label";
+        break;
+      case Ci.nsICookiePermission.ACCESS_ALLOW_FIRST_PARTY_ONLY:
+        stringKey = "permission-can-access-first-party-label";
+        break;
+      case Ci.nsICookiePermission.ACCESS_SESSION:
+        stringKey = "permission-can-session-label";
+        break;
+    }
+    let string = await document.l10n.formatValue(stringKey);
+    return string;
+  },
+
+  async addPermission(aCapability) {
+    var textbox = document.getElementById("url");
+    var input_url = textbox.value.trim();
+    let principal;
+    try {
+      // The origin accessor on the principal object will throw if the
+      // principal doesn't have a canonical origin representation. This will
+      // help catch cases where the URI parser parsed something like
+      // `localhost:8080` as having the scheme `localhost`, rather than being
+      // an invalid URI. A canonical origin representation is required by the
+      // permission manager for storage, so this won't prevent any valid
+      // permissions from being entered by the user.
+      let uri;
+      try {
+        uri = Services.io.newURI(input_url);
+        principal = Services.scriptSecurityManager.createContentPrincipal(
+          uri,
+          {}
+        );
+        // If we have ended up with an unknown scheme, the following will throw.
+        principal.origin;
+      } catch (ex) {
+        let scheme =
+          this._type != "image" || !input_url.includes("@")
+            ? "http://"
+            : MAILURI_BASE;
+        uri = Services.io.newURI(scheme + input_url);
+        principal = Services.scriptSecurityManager.createContentPrincipal(
+          uri,
+          {}
+        );
+        // If we have ended up with an unknown scheme, the following will throw.
+        principal.origin;
+      }
+    } catch (ex) {
+      let [title, message] = await document.l10n.formatValues([
+        { id: "invalid-uri-title" },
+        { id: "invalid-uri-message" },
+      ]);
+      Services.prompt.alert(window, title, message);
+      return;
+    }
+
+    var capabilityString = await this._getCapabilityString(aCapability);
+
+    // check whether the permission already exists, if not, add it
+    let permissionExists = false;
+    let capabilityExists = false;
+    for (var i = 0; i < this._permissions.length; ++i) {
+      // Thunderbird compares origins, not principals here.
+      if (this._permissions[i].principal.origin == principal.origin) {
+        permissionExists = true;
+        capabilityExists = this._permissions[i].capability == capabilityString;
+        if (!capabilityExists) {
+          this._permissions[i].capability = capabilityString;
+        }
+        break;
+      }
+    }
+
+    let permissionParams = {
+      principal,
+      type: this._type,
+      capability: aCapability,
+    };
+    if (!permissionExists) {
+      this._permissionsToAdd.set(principal.origin, permissionParams);
+      this._addPermission(permissionParams);
+    } else if (!capabilityExists) {
+      this._permissionsToAdd.set(principal.origin, permissionParams);
+      this._handleCapabilityChange();
+    }
+
+    textbox.value = "";
+    textbox.focus();
+
+    // covers a case where the site exists already, so the buttons don't disable
+    this.onHostInput(textbox);
+
+    // enable "remove all" button as needed
+    document.getElementById("removeAllPermissions").disabled =
+      this._permissions.length == 0;
+  },
+
+  _removePermission(aPermission) {
+    this._removePermissionFromList(aPermission.principal);
+
+    // If this permission was added during this session, let's remove
+    // it from the pending adds list to prevent calls to the
+    // permission manager.
+    let isNewPermission = this._permissionsToAdd.delete(
+      aPermission.principal.origin
+    );
+
+    if (!isNewPermission) {
+      this._permissionsToDelete.set(aPermission.principal.origin, aPermission);
+    }
+  },
+
+  _handleCapabilityChange() {
+    // Re-do the sort, if the status changed from Block to Allow
+    // or vice versa, since if we're sorted on status, we may no
+    // longer be in order.
+    if (this._lastPermissionSortColumn == "statusCol") {
+      this._resortPermissions();
+    }
+    this._tree.invalidate();
+  },
+
+  _addPermission(aPermission) {
+    this._addPermissionToList(aPermission);
+    ++this._view._rowCount;
+    this._tree.rowCountChanged(this._view.rowCount - 1, 1);
+    // Re-do the sort, since we inserted this new item at the end.
+    this._resortPermissions();
+  },
+
+  _resortPermissions() {
+    gTreeUtils.sort(
+      this._tree,
+      this._view,
+      this._permissions,
+      this._lastPermissionSortColumn,
+      this._permissionsComparator,
+      this._lastPermissionSortColumn,
+      !this._lastPermissionSortAscending
+    ); // keep sort direction
+  },
+
+  onHostInput(aSiteField) {
+    document.getElementById("btnSession").disabled = !aSiteField.value;
+    document.getElementById("btnBlock").disabled = !aSiteField.value;
+    document.getElementById("btnAllow").disabled = !aSiteField.value;
+  },
+
+  onWindowKeyPress(aEvent) {
+    if (aEvent.keyCode == KeyEvent.DOM_VK_ESCAPE) {
+      window.close();
+    }
+  },
+
+  onHostKeyPress(aEvent) {
+    if (aEvent.keyCode == KeyEvent.DOM_VK_RETURN) {
+      document.getElementById("btnAllow").click();
+    }
+  },
+
+  onLoad() {
+    var params = window.arguments[0];
+    this.init(params);
+  },
+
+  init(aParams) {
+    if (this._type) {
+      // reusing an open dialog, clear the old observer
+      this.uninit();
+    }
+
+    this._type = aParams.permissionType;
+    this._manageCapability = aParams.manageCapability;
+
+    var permissionsText = document.getElementById("permissionsText");
+    while (permissionsText.hasChildNodes()) {
+      permissionsText.lastChild.remove();
+    }
+    permissionsText.appendChild(document.createTextNode(aParams.introText));
+
+    document.title = aParams.windowTitle;
+
+    document.getElementById("btnBlock").hidden = !aParams.blockVisible;
+    document.getElementById("btnSession").hidden = !aParams.sessionVisible;
+    document.getElementById("btnAllow").hidden = !aParams.allowVisible;
+
+    var urlFieldVisible =
+      aParams.blockVisible || aParams.sessionVisible || aParams.allowVisible;
+
+    var urlField = document.getElementById("url");
+    urlField.value = aParams.prefilledHost;
+    urlField.hidden = !urlFieldVisible;
+
+    this.onHostInput(urlField);
+
+    var urlLabel = document.getElementById("urlLabel");
+    urlLabel.hidden = !urlFieldVisible;
+
+    let treecols = document.getElementsByTagName("treecols")[0];
+    treecols.addEventListener("click", event => {
+      if (event.target.nodeName != "treecol" || event.button != 0) {
+        return;
+      }
+
+      let sortField = event.target.getAttribute("data-field-name");
+      if (!sortField) {
+        return;
+      }
+
+      gPermissionManager.onPermissionSort(sortField);
+    });
+
+    Services.obs.notifyObservers(
+      null,
+      NOTIFICATION_FLUSH_PERMISSIONS,
+      this._type
+    );
+    Services.obs.addObserver(this, "perm-changed");
+
+    this._loadPermissions().then(() => urlField.focus());
+  },
+
+  uninit() {
+    if (!this._observerRemoved) {
+      Services.obs.removeObserver(this, "perm-changed");
+
+      this._observerRemoved = true;
+    }
+  },
+
+  observe(aSubject, aTopic, aData) {
+    if (aTopic == "perm-changed") {
+      var permission = aSubject.QueryInterface(Ci.nsIPermission);
+
+      // Ignore unrelated permission types.
+      if (permission.type != this._type) {
+        return;
+      }
+
+      if (aData == "added") {
+        this._addPermission(permission);
+      } else if (aData == "changed") {
+        for (var i = 0; i < this._permissions.length; ++i) {
+          if (permission.matches(this._permissions[i].principal, true)) {
+            this._permissions[i].capability = this._getCapabilityString(
+              permission.capability
+            );
+            break;
+          }
+        }
+        this._handleCapabilityChange();
+      } else if (aData == "deleted") {
+        this._removePermissionFromList(permission);
+      }
+    }
+  },
+
+  onPermissionSelected() {
+    var hasSelection = this._tree.view.selection.count > 0;
+    var hasRows = this._tree.view.rowCount > 0;
+    document.getElementById("removePermission").disabled =
+      !hasRows || !hasSelection;
+    document.getElementById("removeAllPermissions").disabled = !hasRows;
+  },
+
+  onPermissionDeleted() {
+    if (!this._view.rowCount) {
+      return;
+    }
+    var removedPermissions = [];
+    gTreeUtils.deleteSelectedItems(
+      this._tree,
+      this._view,
+      this._permissions,
+      removedPermissions
+    );
+    for (var i = 0; i < removedPermissions.length; ++i) {
+      var p = removedPermissions[i];
+      this._removePermission(p);
+    }
+    document.getElementById("removePermission").disabled =
+      !this._permissions.length;
+    document.getElementById("removeAllPermissions").disabled =
+      !this._permissions.length;
+  },
+
+  onAllPermissionsDeleted() {
+    if (!this._view.rowCount) {
+      return;
+    }
+    var removedPermissions = [];
+    gTreeUtils.deleteAll(
+      this._tree,
+      this._view,
+      this._permissions,
+      removedPermissions
+    );
+    for (var i = 0; i < removedPermissions.length; ++i) {
+      var p = removedPermissions[i];
+      this._removePermission(p);
+    }
+    document.getElementById("removePermission").disabled = true;
+    document.getElementById("removeAllPermissions").disabled = true;
+  },
+
+  onPermissionKeyPress(aEvent) {
+    if (
+      aEvent.keyCode == KeyEvent.DOM_VK_DELETE ||
+      (AppConstants.platform == "macosx" &&
+        aEvent.keyCode == KeyEvent.DOM_VK_BACK_SPACE)
+    ) {
+      this.onPermissionDeleted();
+    }
+  },
+
+  _lastPermissionSortColumn: "",
+  _lastPermissionSortAscending: false,
+  _permissionsComparator(a, b) {
+    return a.toLowerCase().localeCompare(b.toLowerCase());
+  },
+
+  onPermissionSort(aColumn) {
+    this._lastPermissionSortAscending = gTreeUtils.sort(
+      this._tree,
+      this._view,
+      this._permissions,
+      aColumn,
+      this._permissionsComparator,
+      this._lastPermissionSortColumn,
+      this._lastPermissionSortAscending
+    );
+    this._lastPermissionSortColumn = aColumn;
+  },
+
+  onApplyChanges() {
+    // Stop observing permission changes since we are about
+    // to write out the pending adds/deletes and don't need
+    // to update the UI
+    this.uninit();
+
+    for (let permissionParams of this._permissionsToAdd.values()) {
+      Services.perms.addFromPrincipal(
+        permissionParams.principal,
+        permissionParams.type,
+        permissionParams.capability
+      );
+    }
+
+    for (let p of this._permissionsToDelete.values()) {
+      Services.perms.removeFromPrincipal(p.principal, p.type);
+    }
+
+    window.close();
+  },
+
+  async _loadPermissions() {
+    this._tree = document.getElementById("permissionsTree");
+    this._permissions = [];
+
+    for (let perm of Services.perms.all) {
+      await this._addPermissionToList(perm);
+    }
+
+    this._view._rowCount = this._permissions.length;
+
+    // sort and display the table
+    this._tree.view = this._view;
+    this.onPermissionSort("origin");
+
+    // disable "remove all" button if there are none
+    document.getElementById("removeAllPermissions").disabled =
+      this._permissions.length == 0;
+  },
+
+  async _addPermissionToList(aPermission) {
+    if (
+      aPermission.type == this._type &&
+      (!this._manageCapability ||
+        aPermission.capability == this._manageCapability)
+    ) {
+      var principal = aPermission.principal;
+      var capabilityString = await this._getCapabilityString(
+        aPermission.capability
+      );
+      var p = new Permission(principal, aPermission.type, capabilityString);
+      this._permissions.push(p);
+    }
+  },
+
+  _removePermissionFromList(aPrincipal) {
+    for (let i = 0; i < this._permissions.length; ++i) {
+      // Thunderbird compares origins, not principals here.
+      if (this._permissions[i].principal.origin == aPrincipal.origin) {
+        this._permissions.splice(i, 1);
+        this._view._rowCount--;
+        this._tree.rowCountChanged(this._view.rowCount - 1, -1);
+        this._tree.invalidate();
+        break;
+      }
+    }
+  },
+
+  setOrigin(aOrigin) {
+    document.getElementById("url").value = aOrigin;
+  },
+};
+
+function setOrigin(aOrigin) {
+  gPermissionManager.setOrigin(aOrigin);
+}
+
+function initWithParams(aParams) {
+  gPermissionManager.init(aParams);
+}
diff --git a/comm/mail/components/preferences/permissions.xhtml b/comm/mail/components/preferences/permissions.xhtml
new file mode 100644
index 0000000000..33340d3f63
--- /dev/null
+++ b/comm/mail/components/preferences/permissions.xhtml
@@ -0,0 +1,128 @@
+<?xml version="1.0"?>
+
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+<?xml-stylesheet href="chrome://messenger/skin/input-fields.css"?>
+
+<!DOCTYPE dialog>
+
+<window
+  id="PermissionsDialog"
+  class="windowDialog"
+  data-l10n-id="permissions-reminder-window2"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  onload="gPermissionManager.onLoad();"
+  onunload="gPermissionManager.uninit();"
+  persist="width height"
+  onkeypress="gPermissionManager.onWindowKeyPress(event);"
+>
+  <script src="chrome://messenger/content/globalOverlay.js" />
+  <script src="chrome://global/content/editMenuOverlay.js" />
+  <script src="chrome://global/content/treeUtils.js" />
+  <script src="chrome://messenger/content/preferences/permissions.js" />
+
+  <linkset>
+    <html:link
+      rel="localization"
+      href="messenger/preferences/permissions.ftl"
+    />
+  </linkset>
+
+  <keyset>
+    <key
+      data-l10n-id="permission-preferences-close-window"
+      data-l10n-attrs="key"
+      modifiers="accel"
+      oncommand="window.close();"
+    />
+  </keyset>
+
+  <vbox class="contentPane largeDialogContainer" flex="1">
+    <description id="permissionsText" control="url" />
+    <separator class="thin" />
+    <label id="urlLabel" control="url" data-l10n-id="website-address-label" />
+    <hbox align="start" class="input-container">
+      <html:input
+        id="url"
+        type="text"
+        oninput="gPermissionManager.onHostInput(event.target);"
+        onkeypress="gPermissionManager.onHostKeyPress(event);"
+      />
+    </hbox>
+    <hbox pack="end">
+      <button
+        id="btnBlock"
+        disabled="true"
+        data-l10n-id="block-button"
+        oncommand="gPermissionManager.addPermission(Ci.nsIPermissionManager.DENY_ACTION);"
+      />
+      <button
+        id="btnSession"
+        disabled="true"
+        data-l10n-id="allow-session-button"
+        oncommand="gPermissionManager.addPermission(Ci.nsICookiePermission.ACCESS_SESSION);"
+      />
+      <button
+        id="btnAllow"
+        disabled="true"
+        data-l10n-id="allow-button"
+        default="true"
+        oncommand="gPermissionManager.addPermission(Ci.nsIPermissionManager.ALLOW_ACTION);"
+      />
+    </hbox>
+    <separator class="thin" />
+    <tree
+      id="permissionsTree"
+      flex="1"
+      style="height: 18em"
+      hidecolumnpicker="true"
+      onkeypress="gPermissionManager.onPermissionKeyPress(event)"
+      onselect="gPermissionManager.onPermissionSelected();"
+    >
+      <treecols>
+        <treecol
+          id="siteCol"
+          data-l10n-id="treehead-sitename-label"
+          data-field-name="rawHost"
+          persist="width"
+        />
+        <splitter class="tree-splitter" />
+        <treecol
+          id="statusCol"
+          data-l10n-id="treehead-status-label"
+          data-field-name="capability"
+          persist="width"
+        />
+      </treecols>
+      <treechildren />
+    </tree>
+  </vbox>
+  <vbox>
+    <hbox class="actionButtons" flex="1">
+      <button
+        id="removePermission"
+        disabled="true"
+        data-l10n-id="remove-site-button"
+        oncommand="gPermissionManager.onPermissionDeleted();"
+      />
+      <button
+        id="removeAllPermissions"
+        data-l10n-id="remove-all-site-button"
+        oncommand="gPermissionManager.onAllPermissionsDeleted();"
+      />
+    </hbox>
+    <spacer flex="1" />
+    <hbox class="actionButtons" pack="end" flex="1">
+      <button oncommand="window.close();" data-l10n-id="cancel-button" />
+      <button
+        id="btnApplyChanges"
+        oncommand="gPermissionManager.onApplyChanges();"
+        data-l10n-id="save-button"
+      />
+    </hbox>
+  </vbox>
+</window>
diff --git a/comm/mail/components/preferences/preferences.js b/comm/mail/components/preferences/preferences.js
new file mode 100644
index 0000000000..1a123527ca
--- /dev/null
+++ b/comm/mail/components/preferences/preferences.js
@@ -0,0 +1,453 @@
+/* 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-globals-from ../../../../toolkit/content/preferencesBindings.js */
+/* import-globals-from general.js */
+/* import-globals-from compose.js */
+/* import-globals-from downloads.js */
+/* import-globals-from privacy.js */
+/* import-globals-from chat.js */
+/* import-globals-from sync.js */
+/* import-globals-from findInPage.js */
+/* globals gCalendarPane */
+
+var { AppConstants } = ChromeUtils.importESModule(
+  "resource://gre/modules/AppConstants.sys.mjs"
+);
+var { MailServices } = ChromeUtils.import(
+  "resource:///modules/MailServices.jsm"
+);
+var { ExtensionSupport } = ChromeUtils.import(
+  "resource:///modules/ExtensionSupport.jsm"
+);
+var { calendarDeactivator } = ChromeUtils.import(
+  "resource:///modules/calendar/calCalendarDeactivator.jsm"
+);
+var { UIDensity } = ChromeUtils.import("resource:///modules/UIDensity.jsm");
+var { UIFontSize } = ChromeUtils.import("resource:///modules/UIFontSize.jsm");
+
+var paneDeck = document.getElementById("paneDeck");
+var defaultPane = "paneGeneral";
+
+ChromeUtils.defineESModuleGetters(this, {
+  AddonManager: "resource://gre/modules/AddonManager.sys.mjs",
+});
+
+XPCOMUtils.defineLazyGetter(this, "gSubDialog", function () {
+  const { SubDialogManager } = ChromeUtils.importESModule(
+    "resource://gre/modules/SubDialog.sys.mjs"
+  );
+  return new SubDialogManager({
+    dialogStack: document.getElementById("dialogStack"),
+    dialogTemplate: document.getElementById("dialogTemplate"),
+    dialogOptions: {
+      styleSheets: [
+        "chrome://messenger/skin/preferences/dialog.css",
+        "chrome://messenger/skin/preferences/preferences.css",
+      ],
+      resizeCallback: ({ title, frame }) => {
+        UIFontSize.registerWindow(frame.contentWindow);
+
+        // Search within main document and highlight matched keyword.
+        gSearchResultsPane.searchWithinNode(title, gSearchResultsPane.query);
+
+        // Search within sub-dialog document and highlight matched keyword.
+        gSearchResultsPane.searchWithinNode(
+          frame.contentDocument.firstElementChild,
+          gSearchResultsPane.query
+        );
+
+        // Creating tooltips for all the instances found
+        for (let node of gSearchResultsPane.listSearchTooltips) {
+          if (!node.tooltipNode) {
+            gSearchResultsPane.createSearchTooltip(
+              node,
+              gSearchResultsPane.query
+            );
+          }
+        }
+
+        // Resize the dialog to fit the content with edited font size.
+        requestAnimationFrame(() => {
+          let dialogs = frame.ownerGlobal.gSubDialog._dialogs;
+          let dialog = dialogs.find(
+            d => d._frame.contentDocument == frame.contentDocument
+          );
+          if (dialog) {
+            UIFontSize.resizeSubDialog(dialog);
+          }
+        });
+      },
+    },
+  });
+});
+
+document.addEventListener("DOMContentLoaded", init, { once: true });
+
+var gCategoryInits = new Map();
+var gLastCategory = { category: undefined, subcategory: undefined };
+
+function init_category_if_required(category) {
+  let categoryInfo = gCategoryInits.get(category);
+  if (!categoryInfo) {
+    throw new Error(
+      "Unknown in-content prefs category! Can't init " + category
+    );
+  }
+  if (categoryInfo.inited) {
+    return null;
+  }
+  return categoryInfo.init();
+}
+
+function register_module(categoryName, categoryObject) {
+  gCategoryInits.set(categoryName, {
+    inited: false,
+    async init() {
+      let template = document.getElementById(categoryName);
+      if (template) {
+        // Replace the template element with the nodes inside of it.
+        let frag = template.content;
+        await document.l10n.translateFragment(frag);
+
+        // Actually insert them into the DOM.
+        document.l10n.pauseObserving();
+        template.replaceWith(frag);
+        document.l10n.resumeObserving();
+
+        // Asks Preferences to update the attribute value of the entire
+        // document again (this can be simplified if we could separate the
+        // preferences of each pane.)
+        Preferences.queueUpdateOfAllElements();
+      }
+      categoryObject.init();
+      this.inited = true;
+    },
+  });
+}
+
+function init() {
+  register_module("paneGeneral", gGeneralPane);
+  register_module("paneCompose", gComposePane);
+  register_module("panePrivacy", gPrivacyPane);
+  register_module("paneCalendar", gCalendarPane);
+  if (AppConstants.NIGHTLY_BUILD) {
+    register_module("paneSync", gSyncPane);
+  }
+  register_module("paneSearchResults", gSearchResultsPane);
+  if (Services.prefs.getBoolPref("mail.chat.enabled")) {
+    register_module("paneChat", gChatPane);
+  } else {
+    // Remove the pane from the DOM so it doesn't get incorrectly included in
+    // the search results.
+    document.getElementById("paneChat").remove();
+  }
+
+  // If no calendar is currently enabled remove it from the DOM so it doesn't
+  // get incorrectly included in the search results.
+  if (!calendarDeactivator.isCalendarActivated) {
+    document.getElementById("paneCalendar").remove();
+    document.getElementById("category-calendar").remove();
+  }
+  gSearchResultsPane.init();
+
+  let categories = document.getElementById("categories");
+  categories.addEventListener("select", event => gotoPref(event.target.value));
+
+  document.documentElement.addEventListener("keydown", event => {
+    if (event.key == "Tab") {
+      categories.setAttribute("keyboard-navigation", "true");
+    } else if ((event.ctrlKey || event.metaKey) && event.key == "f") {
+      document.getElementById("searchInput").focus();
+      event.preventDefault();
+    }
+  });
+
+  categories.addEventListener("mousedown", function () {
+    this.removeAttribute("keyboard-navigation");
+  });
+
+  window.addEventListener("hashchange", onHashChange);
+  let lastSelected = Services.xulStore.getValue(
+    "about:preferences",
+    "paneDeck",
+    "lastSelected"
+  );
+  gotoPref(lastSelected);
+
+  UIDensity.registerWindow(window);
+  UIFontSize.registerWindow(window);
+}
+
+function onHashChange() {
+  gotoPref();
+}
+
+async function gotoPref(aCategory) {
+  let categories = document.getElementById("categories");
+  const kDefaultCategoryInternalName = "paneGeneral";
+  const kDefaultCategory = "general";
+  let hash = document.location.hash;
+
+  let category = aCategory || hash.substr(1) || kDefaultCategoryInternalName;
+  let breakIndex = category.indexOf("-");
+  // Subcategories allow for selecting smaller sections of the preferences
+  // until proper search support is enabled (bug 1353954).
+  let subcategory = breakIndex != -1 && category.substring(breakIndex + 1);
+  if (subcategory) {
+    category = category.substring(0, breakIndex);
+  }
+  category = friendlyPrefCategoryNameToInternalName(category);
+  if (category != "paneSearchResults") {
+    gSearchResultsPane.query = null;
+    gSearchResultsPane.searchInput.value = "";
+    gSearchResultsPane.getFindSelection(window).removeAllRanges();
+    gSearchResultsPane.removeAllSearchTooltips();
+    gSearchResultsPane.removeAllSearchMenuitemIndicators();
+  } else if (!gSearchResultsPane.searchInput.value) {
+    // Something tried to send us to the search results pane without
+    // a query string. Default to the General pane instead.
+    category = kDefaultCategoryInternalName;
+    document.location.hash = kDefaultCategory;
+    gSearchResultsPane.query = null;
+  }
+
+  // Updating the hash (below) or changing the selected category
+  // will re-enter gotoPref.
+  if (gLastCategory.category == category && !subcategory) {
+    return;
+  }
+
+  let item;
+  if (category != "paneSearchResults") {
+    // Hide second level headers in normal view
+    for (let element of document.querySelectorAll(".search-header")) {
+      element.hidden = true;
+    }
+
+    item = categories.querySelector(".category[value=" + category + "]");
+    if (!item) {
+      category = kDefaultCategoryInternalName;
+      item = categories.querySelector(".category[value=" + category + "]");
+    }
+  }
+
+  if (
+    gLastCategory.category ||
+    category != kDefaultCategoryInternalName ||
+    subcategory
+  ) {
+    let friendlyName = internalPrefCategoryNameToFriendlyName(category);
+    document.location.hash = friendlyName;
+  }
+  // Need to set the gLastCategory before setting categories.selectedItem since
+  // the categories 'select' event will re-enter the gotoPref codepath.
+  gLastCategory.category = category;
+  gLastCategory.subcategory = subcategory;
+  if (item) {
+    categories.selectedItem = item;
+  } else {
+    categories.clearSelection();
+  }
+  window.history.replaceState(category, document.title);
+
+  try {
+    await init_category_if_required(category);
+  } catch (ex) {
+    console.error(
+      new Error(
+        "Error initializing preference category " + category + ": " + ex
+      )
+    );
+    throw ex;
+  }
+
+  // Bail out of this goToPref if the category
+  // or subcategory changed during async operation.
+  if (
+    gLastCategory.category !== category ||
+    gLastCategory.subcategory !== subcategory
+  ) {
+    return;
+  }
+
+  search(category, "data-category");
+
+  let mainContent = document.querySelector(".main-content");
+  mainContent.scrollTop = 0;
+
+  spotlight(subcategory, category);
+
+  document.dispatchEvent(new CustomEvent("paneSelected", { bubbles: true }));
+  document.getElementById("preferencesContainer").scrollTo(0, 0);
+  document.getElementById("paneDeck").setAttribute("lastSelected", category);
+  Services.xulStore.setValue(
+    "about:preferences",
+    "paneDeck",
+    "lastSelected",
+    category
+  );
+}
+
+function friendlyPrefCategoryNameToInternalName(aName) {
+  if (aName.startsWith("pane")) {
+    return aName;
+  }
+  return "pane" + aName.substring(0, 1).toUpperCase() + aName.substr(1);
+}
+
+// This function is duplicated inside of utilityOverlay.js's openPreferences.
+function internalPrefCategoryNameToFriendlyName(aName) {
+  return (aName || "").replace(/^pane./, function (toReplace) {
+    return toReplace[4].toLowerCase();
+  });
+}
+
+function search(aQuery, aAttribute) {
+  let paneDeck = document.getElementById("paneDeck");
+  let elements = paneDeck.children;
+  for (let element of elements) {
+    // If the "data-hidden-from-search" is "true", the
+    // element will not get considered during search.
+    if (
+      element.getAttribute("data-hidden-from-search") != "true" ||
+      element.getAttribute("data-subpanel") == "true"
+    ) {
+      let attributeValue = element.getAttribute(aAttribute);
+      if (attributeValue == aQuery) {
+        element.hidden = false;
+      } else {
+        element.hidden = true;
+      }
+    } else if (
+      element.getAttribute("data-hidden-from-search") == "true" &&
+      !element.hidden
+    ) {
+      element.hidden = true;
+    }
+    element.classList.remove("visually-hidden");
+  }
+
+  let keysets = paneDeck.getElementsByTagName("keyset");
+  for (let element of keysets) {
+    let attributeValue = element.getAttribute(aAttribute);
+    if (attributeValue == aQuery) {
+      element.removeAttribute("disabled");
+    } else {
+      element.setAttribute("disabled", true);
+    }
+  }
+}
+
+async function spotlight(subcategory, category) {
+  let highlightedElements = document.querySelectorAll(".spotlight");
+  if (highlightedElements.length) {
+    for (let element of highlightedElements) {
+      element.classList.remove("spotlight");
+    }
+  }
+  if (subcategory) {
+    scrollAndHighlight(subcategory, category);
+  }
+}
+
+async function scrollAndHighlight(subcategory, category) {
+  let element = document.querySelector(`[data-subcategory="${subcategory}"]`);
+  if (!element) {
+    return;
+  }
+  let header = getClosestDisplayedHeader(element);
+
+  scrollContentTo(header);
+  element.classList.add("spotlight");
+}
+
+/**
+ * If there is no visible second level header it will return first level header,
+ * otherwise return second level header.
+ *
+ * @returns {Element} The closest displayed header.
+ */
+function getClosestDisplayedHeader(element) {
+  let header = element.closest("groupbox");
+  let searchHeader = header.querySelector(".search-header");
+  if (
+    searchHeader &&
+    searchHeader.hidden &&
+    header.previousElementSibling.classList.contains("subcategory")
+  ) {
+    header = header.previousElementSibling;
+  }
+  return header;
+}
+
+function scrollContentTo(element) {
+  const STICKY_CONTAINER_HEIGHT =
+    document.querySelector(".sticky-container").clientHeight;
+  let mainContent = document.querySelector(".main-content");
+  let top = element.getBoundingClientRect().top - STICKY_CONTAINER_HEIGHT;
+  mainContent.scroll({
+    top,
+    behavior: "smooth",
+  });
+}
+
+/**
+ * Selects the specified preferences pane
+ *
+ * @param paneID              ID of prefpane to select
+ * @param scrollPaneTo        ID of the element to scroll into view
+ * @param otherArgs.subdialog ID of button to activate, opening a subdialog
+ */
+function selectPrefPane(paneID, scrollPaneTo, otherArgs) {
+  if (paneID) {
+    if (gLastCategory.category != paneID) {
+      gotoPref(paneID);
+    }
+    if (scrollPaneTo) {
+      showTab(scrollPaneTo, otherArgs ? otherArgs.subdialog : undefined);
+    }
+  }
+}
+
+/**
+ * Select the specified tab
+ *
+ * @param scrollPaneTo ID of the element to scroll into view
+ * @param subdialogID  ID of button to activate, opening a subdialog
+ */
+function showTab(scrollPaneTo, subdialogID) {
+  setTimeout(function () {
+    let scrollTarget = document.getElementById(scrollPaneTo);
+    if (scrollTarget.closest("groupbox")) {
+      scrollTarget = scrollTarget.closest("groupbox");
+    }
+    scrollTarget.scrollIntoView();
+    if (subdialogID) {
+      document.getElementById(subdialogID).click();
+    }
+  });
+}
+
+/**
+ * Filter the lastFallbackLocale from availableLocales if it doesn't have all
+ * of the needed strings.
+ *
+ * When the lastFallbackLocale isn't the defaultLocale, then by default only
+ * fluent strings are included. To fully use that locale you need the langpack
+ * to be installed, so if it isn't installed remove it from availableLocales.
+ */
+async function getAvailableLocales() {
+  let { availableLocales, defaultLocale, lastFallbackLocale } = Services.locale;
+  // If defaultLocale isn't lastFallbackLocale, then we still need the langpack
+  // for lastFallbackLocale for it to be useful.
+  if (defaultLocale != lastFallbackLocale) {
+    let lastFallbackId = `langpack-${lastFallbackLocale}@thunderbird.mozilla.org`;
+    let lastFallbackInstalled = await AddonManager.getAddonByID(lastFallbackId);
+    if (!lastFallbackInstalled) {
+      return availableLocales.filter(locale => locale != lastFallbackLocale);
+    }
+  }
+  return availableLocales;
+}
diff --git a/comm/mail/components/preferences/preferences.xhtml b/comm/mail/components/preferences/preferences.xhtml
new file mode 100644
index 0000000000..8092f1af97
--- /dev/null
+++ b/comm/mail/components/preferences/preferences.xhtml
@@ -0,0 +1,256 @@
+<?xml version="1.0"?>
+# 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/.
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+<?xml-stylesheet href="chrome://global/skin/popup.css"?>
+<?xml-stylesheet href="chrome://global/skin/autocomplete.css"?>
+<?xml-stylesheet href="chrome://messenger/skin/input-fields.css"?>
+<?xml-stylesheet href="chrome://messenger/skin/preferences/applications.css"?>
+<?xml-stylesheet href="chrome://global/skin/in-content/common.css"?>
+<?xml-stylesheet href="chrome://messenger/skin/preferences/preferences.css"?>
+<?xml-stylesheet href="chrome://calendar/skin/shared/calendar-preferences.css" type="text/css"?>
+<?xml-stylesheet href="chrome://calendar/skin/calendar.css"?>
+
+<!DOCTYPE html [
+<!ENTITY % brandDTD SYSTEM "chrome://branding/locale/brand.dtd">
+%brandDTD;
+<!ENTITY % editorOverlayDTD SYSTEM "chrome://messenger/locale/messengercompose/editorOverlay.dtd">
+%editorOverlayDTD;
+<!ENTITY % lightningDTD SYSTEM "chrome://lightning/locale/lightning.dtd">
+%lightningDTD;
+<!ENTITY % globalDTD SYSTEM "chrome://calendar/locale/global.dtd">
+%globalDTD;
+<!ENTITY % eventDTD SYSTEM "chrome://calendar/locale/calendar-event-dialog.dtd">
+%eventDTD;
+]>
+
+<html id="MailPreferences" xmlns="http://www.w3.org/1999/xhtml"
+      role="document"
+      xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+      xmlns:html="http://www.w3.org/1999/xhtml"
+      scrolling="false">
+<head>
+  <title data-l10n-id="preferences-doc-title2"></title>
+  <meta http-equiv="Content-Security-Policy" content="default-src chrome:; connect-src *; script-src chrome: 'unsafe-inline'; img-src chrome: moz-icon: https: data:; style-src chrome: data: 'unsafe-inline'; object-src 'none'" />
+  <meta name="color-scheme" content="light dark" />
+  <link rel="localization" href="branding/brand.ftl" />
+  <link rel="localization" href="messenger/preferences/preferences.ftl" />
+  <link rel="localization" href="messenger/preferences/fonts.ftl" />
+  <link rel="localization" href="messenger/preferences/languages.ftl" />
+  <link rel="localization" href="messenger/aboutDialog.ftl"/>
+
+  <!-- Links below are only used for search-l10n-ids into subdialogs -->
+  <link rel="localization" href="messenger/preferences/receipts.ftl" />
+  <link rel="localization" href="messenger/preferences/permissions.ftl" />
+  <link rel="localization" href="messenger/preferences/cookies.ftl" />
+  <link rel="localization" href="messenger/preferences/system-integration.ftl" />
+  <link rel="localization" href="messenger/preferences/colors.ftl" />
+  <link rel="localization" href="messenger/preferences/dock-options.ftl" />
+  <link rel="localization" href="messenger/preferences/notifications.ftl" />
+  <link rel="localization" href="messenger/preferences/new-tag.ftl" />
+  <link rel="localization" href="toolkit/updates/history.ftl" />
+  <link rel="localization" href="messenger/preferences/connection.ftl" />
+  <link rel="localization" href="messenger/preferences/offline.ftl" />
+  <link rel="localization" href="toolkit/about/config.ftl" />
+  <link rel="localization" href="messenger/preferences/attachment-reminder.ftl" />
+  <link rel="localization" href="messenger/preferences/passwordManager.ftl" />
+  <link rel="localization" href="security/certificates/certManager.ftl" />
+  <link rel="localization" href="security/certificates/deviceManager.ftl" />
+#ifdef NIGHTLY_BUILD
+  <link rel="localization" href="messenger/preferences/sync-dialog.ftl" />
+  <link rel="localization" href="messenger/firefoxAccounts.ftl" />
+#endif
+
+  <script defer="defer" src="chrome://global/content/preferencesBindings.js"></script>
+#ifdef MOZ_UPDATER
+  <script defer="defer" src="chrome://messenger/content/aboutDialog-appUpdater.js"></script>
+#endif
+  <script defer="defer" src="chrome://messenger/content/globalOverlay.js"></script>
+  <script defer="defer" src="chrome://global/content/editMenuOverlay.js"></script>
+  <script defer="defer" src="chrome://messenger/content/accountUtils.js"></script>
+
+  <script defer="defer" src="chrome://communicator/content/contentAreaClick.js"></script>
+  <script defer="defer" src="chrome://messenger/content/preferences/preferences.js"></script>
+  <script defer="defer" src="chrome://messenger/content/preferences/findInPage.js"></script>
+  <script defer="defer" src="chrome://calendar/content/calendar-ui-utils.js"></script>
+  <script defer="defer" src="chrome://calendar/content/calendar-dialog-utils.js"></script>
+  <script defer="defer" src="chrome://calendar/content/preferences/general.js"></script>
+  <script defer="defer" src="chrome://calendar/content/preferences/alarms.js"></script>
+  <script defer="defer" src="chrome://calendar/content/widgets/calendar-notifications-setting.js"/>
+  <script defer="defer" src="chrome://calendar/content/preferences/notifications.js"/>
+  <script defer="defer" src="chrome://calendar/content/preferences/categories.js"></script>
+  <script defer="defer" src="chrome://calendar/content/preferences/views.js"></script>
+  <script defer="defer" src="chrome://calendar/content/preferences/calendar-preferences.js"></script>
+</head>
+<html:body xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+  <stack id="preferences-stack" flex="1">
+    <hbox id="prefBox" class="main-content" flex="1">
+
+      <vbox id="pref-category-box">
+
+        <!-- category list -->
+        <richlistbox id="categories"
+                     data-l10n-id="category-list"
+                     data-l10n-attrs="aria-label">
+          <richlistitem id="category-general"
+                        class="category"
+                        value="paneGeneral"
+                        data-l10n-id="category-general"
+                        align="center">
+            <html:img class="category-icon"
+                      src="chrome://messenger/skin/icons/new/touch/settings.svg"
+                      alt="" />
+            <label class="category-name" flex="1" data-l10n-id="pane-general-title"/>
+          </richlistitem>
+
+          <richlistitem id="category-compose"
+                        class="category"
+                        value="paneCompose"
+                        data-l10n-id="category-compose"
+                        align="center">
+            <html:img class="category-icon"
+                      src="chrome://messenger/skin/icons/new/touch/pencil.svg"
+                      alt="" />
+            <label class="category-name" flex="1" data-l10n-id="pane-compose-title"/>
+          </richlistitem>
+
+          <richlistitem id="category-privacy"
+                        class="category"
+                        value="panePrivacy"
+                        data-l10n-id="category-privacy"
+                        align="center">
+            <html:img class="category-icon"
+                      src="chrome://messenger/skin/icons/new/touch/lock.svg"
+                      alt="" />
+            <label class="category-name" flex="1" data-l10n-id="pane-privacy-title"/>
+          </richlistitem>
+
+          <richlistitem id="category-chat"
+                        class="category"
+                        value="paneChat"
+                        data-l10n-id="category-chat"
+                        align="center">
+            <html:img class="category-icon"
+                      src="chrome://messenger/skin/icons/new/touch/chat.svg"
+                      alt="" />
+            <label class="category-name" flex="1" data-l10n-id="pane-chat-title"/>
+          </richlistitem>
+
+          <richlistitem id="category-calendar"
+                        class="category"
+                        value="paneCalendar"
+                        data-l10n-id="category-calendar"
+                        align="center">
+            <html:img class="category-icon"
+                      src="chrome://messenger/skin/icons/new/touch/calendar.svg"
+                      alt="" />
+            <label class="category-name" flex="1" data-l10n-id="pane-calendar-title"/>
+          </richlistitem>
+#ifdef NIGHTLY_BUILD
+          <richlistitem id="category-sync"
+                        class="category"
+                        value="paneSync"
+                        data-l10n-id="category-sync"
+                        align="center">
+            <html:img class="category-icon"
+                      src="chrome://messenger/skin/icons/new/touch/sync.svg"
+                      alt="" />
+            <label class="category-name" flex="1" data-l10n-id="pane-sync-title"/>
+          </richlistitem>
+#endif
+        </richlistbox>
+
+        <spacer flex="1"/>
+
+        <vbox class="sidebar-footer-list">
+          <html:a id="accountButton" class="sidebar-footer-link"
+                  onclick="MsgAccountManager(null);">
+            <html:img class="sidebar-footer-icon account-icon"
+                      src="chrome://messenger/skin/icons/new/compact/account-settings.svg"
+                      alt="" />
+            <label data-l10n-id="account-button" class="sidebar-footer-label" flex="1"/>
+          </html:a>
+
+          <html:a id="addonsButton" class="sidebar-footer-link"
+                  onclick="window.browsingContext.topChromeWindow.openAddonsMgr();">
+            <html:img class="sidebar-footer-icon"
+                      src="chrome://messenger/skin/icons/new/compact/extension.svg"
+                      alt="" />
+            <label class="sidebar-footer-label"
+                   data-l10n-id="open-addons-sidebar-button"
+                   flex="1"/>
+          </html:a>
+        </vbox>
+
+      </vbox>
+
+      <vbox id="preferencesContainer" flex="1" align="start">
+        <vbox class="paneDeckContainer">
+          <hbox class="sticky-container" pack="end" align="top" flex="1">
+            <search-textbox id="searchInput"
+                            data-l10n-id="search-preferences-input2"
+                            data-l10n-attrs="placeholder, style"
+                            hidden="true"/>
+          </hbox>
+          <vbox id="paneDeck">
+#include searchResults.inc.xhtml
+#include general.inc.xhtml
+#include compose.inc.xhtml
+#include privacy.inc.xhtml
+#include chat.inc.xhtml
+#include ../../../calendar/base/content/preferences/calendar-preferences.inc.xhtml
+#ifdef NIGHTLY_BUILD
+#include sync.inc.xhtml
+#endif
+          </vbox>
+        </vbox>
+      </vbox>
+    </hbox>
+    <stack id="dialogStack" hidden="true"/>
+    <vbox id="dialogTemplate"
+          class="dialogOverlay"
+          align="center"
+          pack="center"
+          topmost="true"
+          hidden="true">
+      <vbox class="dialogBox"
+            pack="end"
+            role="dialog"
+            aria-labelledby="dialogTitle">
+        <hbox class="dialogTitleBar" align="center">
+          <label class="dialogTitle" flex="1"/>
+          <button class="dialogClose close-icon" data-l10n-id="close-button"/>
+        </hbox>
+        <browser class="dialogFrame"
+                 autoscroll="false"
+                 disablehistory="true"/>
+      </vbox>
+    </vbox>
+  </stack>
+
+  <!-- Helpers for the FileLink options browser select and autocomplete. -->
+  <popupset>
+    <!-- For select dropdowns. The menupopup is what shows the list of options,
+         and the popuponly menulist makes things like the menuactive attributes
+         work correctly on the menupopup. ContentSelectDropdown expects the
+         popuponly menulist to be its immediate parent. -->
+    <menulist popuponly="true" id="ContentSelectDropdown" hidden="true">
+      <menupopup rolluponmousewheel="true"
+                 activateontab="true"
+                 position="after_start"
+                 level="parent"
+#ifdef XP_WIN
+                 consumeoutsideclicks="false"
+                 ignorekeys="shortcuts"
+#endif
+      />
+    </menulist>
+    <panel is="autocomplete-richlistbox-popup" id="PopupAutoComplete"
+           type="autocomplete"
+           role="group"
+           noautofocus="true"/>
+  </popupset>
+</html:body>
+</html>
diff --git a/comm/mail/components/preferences/preferencesTab.js b/comm/mail/components/preferences/preferencesTab.js
new file mode 100644
index 0000000000..0a59fda382
--- /dev/null
+++ b/comm/mail/components/preferences/preferencesTab.js
@@ -0,0 +1,162 @@
+/* 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/. */
+
+// mail/base/content/specialTabs.js
+/* globals contentTabBaseType, DOMLinkHandler */
+
+var { XPCOMUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/XPCOMUtils.sys.mjs"
+);
+var { ExtensionParent } = ChromeUtils.importESModule(
+  "resource://gre/modules/ExtensionParent.sys.mjs"
+);
+
+/**
+ * A tab to show Preferences.
+ */
+var preferencesTabType = {
+  __proto__: contentTabBaseType,
+  name: "preferencesTab",
+  perTabPanel: "vbox",
+  lastBrowserId: 0,
+  bundle: Services.strings.createBundle(
+    "chrome://messenger/locale/messenger.properties"
+  ),
+  protoSvc: Cc["@mozilla.org/uriloader/external-protocol-service;1"].getService(
+    Ci.nsIExternalProtocolService
+  ),
+
+  get loadingTabString() {
+    delete this.loadingTabString;
+    return (this.loadingTabString = document
+      .getElementById("bundle_messenger")
+      .getString("loadingTab"));
+  },
+
+  modes: {
+    preferencesTab: {
+      type: "preferencesTab",
+    },
+  },
+
+  shouldSwitchTo(aArgs) {
+    if (!this.tab) {
+      return -1;
+    }
+    this.tab.browser.contentWindow.selectPrefPane(
+      aArgs.paneID,
+      aArgs.scrollPaneTo,
+      aArgs.otherArgs
+    );
+    return document.getElementById("tabmail").tabInfo.indexOf(this.tab);
+  },
+
+  closeTab(aTab) {
+    this.tab = null;
+  },
+
+  openTab(aTab, aArgs) {
+    aTab.tabNode.setIcon(
+      "chrome://messenger/skin/icons/new/compact/settings.svg"
+    );
+
+    // First clone the page and set up the basics.
+    let clone = document
+      .getElementById("preferencesTab")
+      .firstElementChild.cloneNode(true);
+
+    clone.setAttribute("id", "preferencesTab" + this.lastBrowserId);
+    clone.setAttribute("collapsed", false);
+
+    aTab.panel.setAttribute("id", "preferencesTabWrapper" + this.lastBrowserId);
+    aTab.panel.appendChild(clone);
+
+    // Start setting up the browser.
+    aTab.browser = aTab.panel.querySelector("browser");
+    aTab.browser.setAttribute(
+      "id",
+      "preferencesTabBrowser" + this.lastBrowserId
+    );
+    aTab.browser.setAttribute("autocompletepopup", "PopupAutoComplete");
+    aTab.browser.addEventListener("DOMLinkAdded", DOMLinkHandler);
+
+    aTab.findbar = document.createXULElement("findbar");
+    aTab.findbar.setAttribute(
+      "browserid",
+      "preferencesTabBrowser" + this.lastBrowserId
+    );
+    aTab.panel.appendChild(aTab.findbar);
+
+    // Default to reload being disabled.
+    aTab.reloadEnabled = false;
+
+    aTab.url = "about:preferences";
+    aTab.paneID = aArgs.paneID;
+    aTab.scrollPaneTo = aArgs.scrollPaneTo;
+    aTab.otherArgs = aArgs.otherArgs;
+
+    // Now set up the listeners.
+    this._setUpTitleListener(aTab);
+    this._setUpCloseWindowListener(aTab);
+
+    // Wait for full loading of the tab and the automatic selecting of last tab.
+    // Then run the given onload code.
+    aTab.browser.addEventListener(
+      "paneSelected",
+      function (event) {
+        aTab.pageLoading = false;
+        aTab.pageLoaded = true;
+
+        if ("onLoad" in aArgs) {
+          // Let selection of the initial pane complete before selecting another.
+          // Otherwise we can end up with two panes selected at once.
+          aTab.browser.contentWindow.setTimeout(() => {
+            // By now, the tab could already be closed. Check that it isn't.
+            if (aTab.panel) {
+              aArgs.onLoad(event, aTab.browser);
+            }
+          }, 0);
+        }
+      },
+      { once: true }
+    );
+
+    // Initialize our unit testing variables.
+    aTab.pageLoading = true;
+    aTab.pageLoaded = false;
+
+    // Now start loading the content.
+    aTab.title = this.loadingTabString;
+
+    ExtensionParent.apiManager.emit("extension-browser-inserted", aTab.browser);
+    let params = {
+      triggeringPrincipal: Services.scriptSecurityManager.getSystemPrincipal(),
+      postData: aArgs.postData || null,
+    };
+    aTab.browser.loadURI(Services.io.newURI("about:preferences"), params);
+
+    this.tab = aTab;
+    this.lastBrowserId++;
+  },
+
+  persistTab(aTab) {
+    if (aTab.browser.currentURI.spec == "about:blank") {
+      return null;
+    }
+
+    return {
+      paneID: aTab.paneID,
+      scrollPaneTo: aTab.scrollPaneTo,
+      otherArgs: aTab.otherArgs,
+    };
+  },
+
+  restoreTab(aTabmail, aPersistedState) {
+    aTabmail.openTab("preferencesTab", {
+      paneID: aPersistedState.paneID,
+      scrollPaneTo: aPersistedState.scrollPaneTo,
+      otherArgs: aPersistedState.otherArgs,
+    });
+  },
+};
diff --git a/comm/mail/components/preferences/privacy.inc.xhtml b/comm/mail/components/preferences/privacy.inc.xhtml
new file mode 100644
index 0000000000..6afa5bb840
--- /dev/null
+++ b/comm/mail/components/preferences/privacy.inc.xhtml
@@ -0,0 +1,597 @@
+# 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/.
+  <script src="chrome://messenger/content/preferences/privacy.js"/>
+
+  <stringbundle id="bundlePreferences" src="chrome://messenger/locale/preferences/preferences.properties"/>
+  <html:template id="panePrivacy">
+    <hbox id="privacyCategory"
+          class="subcategory"
+          data-category="panePrivacy">
+      <html:h1 data-l10n-id="privacy-main-header"></html:h1>
+    </hbox>
+
+    <!-- Mail Content -->
+    <html:div data-category="panePrivacy">
+    <html:fieldset id="mailContentGroup" data-category="panePrivacy">
+      <html:legend data-l10n-id="mail-content"></html:legend>
+      <hbox id="remoteContentBox">
+        <checkbox id="acceptRemoteContent"
+                  preference="mailnews.message_display.disable_remote_image"
+                  data-l10n-id="remote-content-label"/>
+        <spacer flex="1"/>
+        <hbox>
+          <button is="highlightable-button" id="remoteContentExceptions"
+                  oncommand="gPrivacyPane.showRemoteContentExceptions();"
+                  data-l10n-id="exceptions-button"
+                  search-l10n-ids="
+                    permissions-reminder-window2.title,
+                    website-address-label.value,
+                    block-button.label,
+                    allow-session-button.label,
+                    allow-button.label,
+                    treehead-sitename-label.label,
+                    treehead-status-label.label,
+                    remove-site-button.label,
+                    remove-all-site-button.label,
+                    cancel-button.label,
+                    save-button.label,
+                    permission-can-label,
+                    permission-can-access-first-party-label,
+                    permission-can-session-label,
+                    permission-cannot-label,
+                    invalid-uri-message,
+                    invalid-uri-title"/>
+        </hbox>
+      </hbox>
+      <hbox>
+        <label is="text-link" id="acceptRemoteContentInfo"
+               href="https://support.mozilla.org/kb/remote-content-in-messages"
+               data-l10n-id="remote-content-info"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <!-- Web Content -->
+    <html:div data-category="panePrivacy">
+    <html:fieldset id="webContentGroup" data-category="panePrivacy">
+      <html:legend data-l10n-id="web-content"></html:legend>
+      <checkbox id="keepHistory"
+                preference="places.history.enabled"
+                data-l10n-id="history-label"/>
+      <hbox id="cookiesBox">
+        <checkbox id="acceptCookies"
+                  preference="network.cookie.cookieBehavior"
+                  data-l10n-id="cookies-label"/>
+        <spacer flex="1"/>
+        <hbox>
+          <button is="highlightable-button" id="cookieExceptions"
+                  oncommand="gPrivacyPane.showCookieExceptions();"
+                  data-l10n-id="exceptions-button"
+                  preference="pref.privacy.disable_button.cookie_exceptions"
+                  search-l10n-ids="
+                    permissions-reminder-window2.title,
+                    website-address-label.value,
+                    block-button.label,
+                    allow-session-button.label,
+                    allow-button.label,
+                    treehead-sitename-label.label,
+                    treehead-status-label.label,
+                    remove-site-button.label,
+                    remove-all-site-button.label,
+                    cancel-button.label,
+                    save-button.label,
+                    permission-can-label,
+                    permission-can-access-first-party-label,
+                    permission-can-session-label,
+                    permission-cannot-label,
+                    invalid-uri-message,
+                    invalid-uri-title"/>
+        </hbox>
+      </hbox>
+      <hbox id="acceptThirdPartyRow" class="indent">
+        <hbox id="acceptThirdPartyBox" align="center">
+          <label id="acceptThirdPartyLabel" control="acceptThirdPartyMenu"
+                 data-l10n-id="third-party-label"/>
+          <hbox>
+            <menulist id="acceptThirdPartyMenu" preference="network.cookie.cookieBehavior">
+              <menupopup>
+                <menuitem data-l10n-id="third-party-always" value="always"/>
+                <menuitem data-l10n-id="third-party-visited" value="visited"/>
+                <menuitem data-l10n-id="third-party-never" value="never"/>
+              </menupopup>
+            </menulist>
+          </hbox>
+        </hbox>
+        <hbox flex="1"/>
+        <hbox>
+          <button is="highlightable-button" id="showCookiesButton"
+                  data-l10n-id="cookies-button"
+                  oncommand="gPrivacyPane.showCookies();"
+                  preference="pref.privacy.disable_button.view_cookies"
+                  search-l10n-ids="
+                    cookies-window-dialog2.title,
+                    filter-search-label.value,
+                    cookies-on-system-label,
+                    treecol-site-header.label,
+                    treecol-name-header.label,
+                    props-name-label.value,
+                    props-value-label.value,
+                    props-domain-label.value,
+                    props-path-label.value,
+                    props-secure-label.value,
+                    props-expires-label.value,
+                    props-container-label.value,
+                    remove-cookie-button.label,
+                    remove-all-cookies-button.label,
+                    cookie-close-button.label"/>
+        </hbox>
+      </hbox>
+
+      <separator class="thin"/>
+
+      <hbox align="center">
+        <checkbox id="privacyDoNotTrackCheckbox"
+                  class="tail-with-learn-more"
+                  data-l10n-id="do-not-track-label"
+                  preference="privacy.donottrackheader.enabled"/>
+        <label is="text-link" id="doNotTrackInfo"
+               href="https://www.mozilla.org/dnt"
+               data-l10n-id="dnt-learn-more-button"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <hbox id="privacyPasswordsCategory"
+          class="subcategory"
+          data-category="panePrivacy">
+      <html:h1 data-l10n-id="privacy-passwords-header"></html:h1>
+    </hbox>
+
+    <separator data-category="panePrivacy"/>
+
+    <html:div data-category="panePrivacy">
+    <html:fieldset data-category="panePrivacy">
+      <hbox align="center">
+        <description data-l10n-id="passwords-description"/>
+        <spacer flex="1"/>
+        <hbox>
+          <button is="highlightable-button" id="showPasswords"
+                  data-l10n-id="passwords-button"
+                  oncommand="gPrivacyPane.showPasswords();"
+                  preference="pref.privacy.disable_button.view_passwords"
+                  search-l10n-ids="
+                    saved-logins.title,
+                    copy-provider-url-cmd.label,
+                    copy-username-cmd.label,
+                    edit-username-cmd.label,
+                    copy-password-cmd.label,
+                    edit-password-cmd.label,
+                    search-filter.placeholder,
+                    column-heading-provider.label,
+                    column-heading-username.label,
+                    column-heading-password.label,
+                    column-heading-time-created.label,
+                    column-heading-time-last-used.label,
+                    column-heading-time-password-changed.label,
+                    column-heading-times-used.label,
+                    remove.label,
+                    import.label,
+                    show-passwords.label,
+                    hide-passwords.label,
+                    logins-description-all,
+                    logins-description-filtered,
+                    remove-all.label,
+                    remove-all-shown.label,
+                    remove-all-passwords-prompt,
+                    remove-all-passwords-title,
+                    no-master-password-prompt,
+                    password-os-auth-dialog-message,
+                    password-os-auth-dialog-message-macosx,
+                    password-os-auth-dialog-caption"/>
+        </hbox>
+      </hbox>
+      <!-- XXX button to do a showExceptions()? -->
+
+      <separator class="thin"/>
+
+      <description data-l10n-id="primary-password-description"/>
+      <hbox>
+        <checkbox id="useMasterPassword"
+                  data-l10n-id="primary-password-label"
+                  oncommand="gPrivacyPane.updateMasterPasswordButton();"/>
+        <spacer flex="1"/>
+        <button is="highlightable-button" id="changeMasterPassword"
+                data-l10n-id="primary-password-button"
+                oncommand="gPrivacyPane.changeMasterPassword();"/>
+      </hbox>
+      <!--
+        Those two strings are meant to be invisible and will be used exclusively to provide
+        localization for an alert window.
+      -->
+      <label id="fips-title" hidden="true" data-l10n-id="forms-primary-pw-fips-title"></label>
+      <label id="fips-desc" hidden="true" data-l10n-id="forms-master-pw-fips-desc"></label>
+    </html:fieldset>
+    </html:div>
+
+    <hbox id="privacyJunkCategory"
+          class="subcategory"
+          data-category="panePrivacy">
+      <html:h1 data-l10n-id="privacy-junk-header"></html:h1>
+    </hbox>
+
+    <separator data-category="panePrivacy"/>
+
+    <html:div data-category="panePrivacy">
+    <html:fieldset data-category="panePrivacy">
+      <description data-l10n-id="junk-description"/>
+      <separator class="thin"/>
+      <hbox>
+        <checkbox id="manualMark"
+                  data-l10n-id="junk-label"
+                  preference="mail.spam.manualMark"
+                  oncommand="gPrivacyPane.updateManualMarkMode(this.checked);"/>
+        <spacer flex="1"/>
+      </hbox>
+      <radiogroup id="manualMarkMode"
+                  class="indent"
+                  preference="mail.spam.manualMarkMode"
+                  aria-labelledby="manualMark">
+        <hbox>
+          <radio id="manualMarkMode0"
+                 value="0"
+                 data-l10n-id="junk-move-label"/>
+          <spacer flex="1"/>
+        </hbox>
+        <hbox>
+          <radio id="manualMarkMode1"
+                 value="1"
+                 data-l10n-id="junk-delete-label"/>
+          <spacer flex="1"/>
+        </hbox>
+      </radiogroup>
+      <hbox>
+        <checkbox id="markAsReadOnSpam"
+                  data-l10n-id="junk-read-label"
+                  preference="mail.spam.markAsReadOnSpam"/>
+        <spacer flex="1"/>
+      </hbox>
+      <hbox align="start">
+        <checkbox id="enableJunkLogging" data-l10n-id="junk-log-label"
+                  oncommand="gPrivacyPane.updateJunkLogButton(this.checked);"
+                  preference="mail.spam.logging.enabled"/>
+        <spacer flex="1"/>
+        <button is="highlightable-button" id="openJunkLogButton"
+                data-l10n-id="junk-log-button"
+                oncommand="gPrivacyPane.openJunkLog();"/>
+      </hbox>
+      <hbox align="start">
+        <spacer flex="1"/>
+        <button is="highlightable-button"
+                data-l10n-id="reset-junk-button"
+                oncommand="gPrivacyPane.resetTrainingData()"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+#ifdef MOZ_DATA_REPORTING
+    <hbox id="privacyDataCollectionCategory"
+          class="subcategory"
+          data-category="panePrivacy">
+      <html:h1 data-l10n-id="collection-header"></html:h1>
+    </hbox>
+
+    <html:div data-category="panePrivacy">
+    <html:fieldset data-category="panePrivacy">
+      <description>
+        <label class="tail-with-learn-more" data-l10n-id="collection-description"/>
+        <label id="dataCollectionPrivacyNotice"
+               class="learnMore" is="text-link"
+               data-l10n-id="collection-privacy-notice"/>
+      </description>
+      <description>
+        <html:div id="telemetry-container" hidden="hidden">
+          <html:img id="telemetryInfoIcon" alt=""
+                    src="chrome://global/skin/icons/info.svg" />
+          <html:span id="telemetryDisabledDescription"
+                     class="tail-with-learn-more"
+                     data-l10n-id="collection-health-report-telemetry-disabled">
+          </html:span>
+          <button id="telemetryDataDeletionLearnMore"
+                  class="learnMore" is="text-link"
+                  data-l10n-id="collection-health-report-telemetry-disabled-link"/>
+        </html:div>
+      </description>
+      <vbox data-subcategory="reports">
+        <hbox align="center">
+          <checkbox id="submitHealthReportBox"
+                    data-l10n-id="collection-health-report"
+                    class="tail-with-learn-more"/>
+          <label id="FHRLearnMore"
+                 class="learnMore" is="text-link"
+                 data-l10n-id="collection-health-report-link"/>
+        </hbox>
+#ifndef MOZ_TELEMETRY_REPORTING
+        <description id="TelemetryDisabledDesc"
+          class="indent tip-caption" control="telemetryGroup"
+          data-l10n-id="collection-health-report-disabled"/>
+#endif
+
+#ifdef MOZ_CRASHREPORTER
+      <hbox align="center">
+        <checkbox id="automaticallySubmitCrashesBox"
+                  class="tail-with-learn-more"
+                  preference="browser.crashReports.unsubmittedCheck.autoSubmit2"
+                  data-l10n-id="collection-backlogged-crash-reports"/>
+        <label id="crashReporterLearnMore"
+               class="learnMore" is="text-link" data-l10n-id="collection-backlogged-crash-reports-link"/>
+      </hbox>
+#endif
+      </vbox>
+    </html:fieldset>
+    </html:div>
+#endif
+
+    <hbox id="privacySecurityCategory"
+          class="subcategory"
+          data-category="panePrivacy">
+      <html:h1 data-l10n-id="privacy-security-header"></html:h1>
+    </hbox>
+
+    <html:div data-category="panePrivacy">
+    <html:fieldset data-category="panePrivacy">
+      <html:legend data-l10n-id="privacy-scam-detection-title"></html:legend>
+      <description data-l10n-id="phishing-description"/>
+      <separator class="thin"/>
+      <hbox>
+        <checkbox id="enablePhishingDetector"
+                  data-l10n-id="phishing-label"
+                  preference="mail.phishing.detection.enabled"/>
+        <spacer flex="1"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <!-- Anti Virus -->
+    <html:div data-category="panePrivacy">
+    <html:fieldset data-category="panePrivacy">
+      <html:legend data-l10n-id="privacy-anti-virus-title"></html:legend>
+      <description data-l10n-id="antivirus-description"/>
+      <separator class="thin"/>
+      <hbox>
+        <checkbox id="enableAntiVirusQuarantine"
+                  data-l10n-id="antivirus-label"
+                  preference="mailnews.downloadToTempFile"/>
+        <spacer flex="1"/>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="panePrivacy">
+    <html:fieldset data-category="panePrivacy">
+      <html:legend data-l10n-id="privacy-certificates-title"></html:legend>
+      <description id="CertSelectionDesc" control="certSelection"
+                   data-l10n-id="certificate-description"/>
+
+      <!--
+        The values on these radio buttons may look like l12y issues, but
+        they're not - this preference uses *those strings* as its values.
+        I KID YOU NOT.
+      -->
+      <radiogroup id="certSelection" class="indent"
+                  orient="horizontal" preftype="string"
+                  preference="security.default_personal_cert"
+                  aria-labelledby="CertGroupCaption CertSelectionDesc">
+        <radio id="certSelectionAuto"
+               data-l10n-id="certificate-auto"
+               value="Select Automatically"/>
+        <radio id="certSelectionAsk"
+               data-l10n-id="certificate-ask"
+               value="Ask Every Time"/>
+      </radiogroup>
+
+      <separator/>
+
+      <hbox align="start">
+        <checkbox id="enableOCSP"
+                  data-l10n-id="ocsp-label"
+                  preference="security.OCSP.enabled"
+                  flex="1"/>
+        <spacer flex="1"/>
+        <vbox>
+          <hbox flex="1">
+            <button is="highlightable-button" id="manageCertificatesButton"
+                    data-l10n-id="certificate-button"
+                    flex="1"
+                    oncommand="gPrivacyPane.showCertificates();"
+                    preference="security.disable_button.openCertManager"
+                    search-l10n-ids="
+                      certmgr-title.title,
+                      certmgr-tab-mine.label,
+                      certmgr-tab-remembered.label,
+                      certmgr-tab-people.label,
+                      certmgr-tab-servers.label,
+                      certmgr-tab-ca.label,
+                      certmgr-mine,
+                      certmgr-remembered,
+                      certmgr-people,
+                      certmgr-ca,
+                      certmgr-server,
+                      certmgr-edit-ca-cert2.title,
+                      certmgr-edit-cert-edit-trust,
+                      certmgr-edit-cert-trust-ssl.label,
+                      certmgr-edit-cert-trust-email.label,
+                      certmgr-delete-cert2.title,
+                      certmgr-cert-host.label,
+                      certmgr-cert-name.label,
+                      certmgr-cert-server.label,
+                      certmgr-token-name.label,
+                      certmgr-begins-label.label,
+                      certmgr-expires-label.label,
+                      certmgr-email.label,
+                      certmgr-serial.label,
+                      certmgr-fingerprint-sha-256.label,
+                      certmgr-view.label,
+                      certmgr-edit.label,
+                      certmgr-export.label,
+                      certmgr-delete.label,
+                      certmgr-delete-builtin.label,
+                      certmgr-backup.label,
+                      certmgr-backup-all.label,
+                      certmgr-restore.label,
+                      certmgr-add-exception.label,
+                      exception-mgr.title,
+                      exception-mgr-extra-button.label,
+                      exception-mgr-supplemental-warning,
+                      exception-mgr-cert-location-url.value,
+                      exception-mgr-cert-location-download.label,
+                      exception-mgr-cert-status-view-cert.label,
+                      exception-mgr-permanent.label,
+                      pk11-bad-password,
+                      pkcs12-decode-err,
+                      pkcs12-unknown-err-restore,
+                      pkcs12-unknown-err-backup,
+                      pkcs12-unknown-err,
+                      pkcs12-info-no-smartcard-backup,
+                      pkcs12-dup-data,
+                      choose-p12-backup-file-dialog,
+                      file-browse-pkcs12-spec,
+                      choose-p12-restore-file-dialog,
+                      file-browse-certificate-spec,
+                      import-ca-certs-prompt,
+                      import-email-cert-prompt,
+                      delete-user-cert-title.title,
+                      delete-user-cert-confirm,
+                      delete-user-cert-impact,
+                      delete-ca-cert-title.title,
+                      delete-ca-cert-confirm,
+                      delete-ca-cert-impact,
+                      delete-ssl-override-title.title,
+                      delete-ssl-override-confirm,
+                      delete-ssl-override-impact,
+                      delete-email-cert-title.title,
+                      delete-email-cert-confirm,
+                      delete-email-cert-impact,
+                      send-no-client-certificate,
+                      no-cert-stored-for-override,
+                      permanent-override,
+                      temporary-override,
+                      add-exception-branded-warning,
+                      add-exception-invalid-header,
+                      add-exception-domain-mismatch-short,
+                      add-exception-domain-mismatch-long,
+                      add-exception-expired-short,
+                      add-exception-expired-long,
+                      add-exception-unverified-or-bad-signature-short,
+                      add-exception-unverified-or-bad-signature-long,
+                      add-exception-valid-short,
+                      add-exception-valid-long,
+                      add-exception-checking-short,
+                      add-exception-checking-long,
+                      add-exception-no-cert-short,
+                      add-exception-no-cert-long,
+                      save-cert-as,
+                      cert-format-base64,
+                      cert-format-base64-chain,
+                      write-file-failure,
+                      cert-format-der,
+                      cert-format-pkcs7,
+                      cert-format-pkcs7-chain"/>
+          </hbox>
+          <hbox flex="1">
+            <button is="highlightable-button" id="viewSecurityDevicesButton"
+                    data-l10n-id="security-devices-button"
+                    flex="1"
+                    oncommand="gPrivacyPane.showSecurityDevices();"
+                    preference="security.disable_button.openDeviceManager"
+                    search-l10n-ids="
+                      devmgr-window.title,
+                      devmgr-devlist.label,
+                      devmgr-header-details.label,
+                      devmgr-header-value.label,
+                      devmgr-button-login.label,
+                      devmgr-button-logout.label,
+                      devmgr-button-changepw.label,
+                      devmgr-button-load.label,
+                      devmgr-button-unload.label,
+                      devmgr-button-enable-fips.label,
+                      devmgr-button-disable-fips.label,
+                      load-device.title,
+                      load-device-info,
+                      load-device-modname.value,
+                      load-device-modname-default.value,
+                      load-device-filename.value,
+                      load-device-browse.label,
+                      devinfo-status.label,
+                      devinfo-status-disabled.label,
+                      devinfo-status-not-present.label,
+                      devinfo-status-uninitialized.label,
+                      devinfo-status-not-logged-in.label,
+                      devinfo-status-logged-in.label,
+                      devinfo-status-ready.label,
+                      devinfo-desc.label,
+                      unable-to-toggle-fips,
+                      load-pk11-module-file-picker-title,
+                      fips-nonempty-primary-password-required,
+                      load-module-help-root-certs-module-name.value,
+                      add-module-failure,
+                      del-module-warning,
+                      del-module-error,
+                      devinfo-man-id.label,
+                      devinfo-hwversion.label,
+                      load-module-help-empty-module-name.value,
+                      devinfo-fwversion.label,
+                      devinfo-modname.label,
+                      devinfo-modpath.label,
+                      login-failed,
+                      devinfo-label.label,
+                      devinfo-serialnum"/>
+          </hbox>
+        </vbox>
+      </hbox>
+    </html:fieldset>
+    </html:div>
+
+    <!-- Email End-To-End Encryption -->
+    <hbox id="privacyCategory"
+          class="subcategory"
+          data-category="panePrivacy">
+      <html:h1 data-l10n-id="email-e2ee-header"></html:h1>
+    </hbox>
+
+    <html:div data-category="panePrivacy">
+    <html:fieldset id="emailE2eeGroupPreparation" data-category="panePrivacy">
+      <description data-l10n-id="email-e2ee-enable-info"/>
+      <html:button id="settingsButton"
+              type="button"
+              data-l10n-id="account-button"
+              class="button button-flat"
+              onclick="window.browsingContext.topChromeWindow.MsgAccountManager(null);">
+      </html:button>
+    </html:fieldset>
+    </html:div>
+
+    <html:div data-category="panePrivacy">
+    <html:fieldset id="emailE2eeGroupAutomatism" data-category="panePrivacy">
+      <html:legend data-l10n-id="email-e2ee-automatism"></html:legend>
+      <description data-l10n-id="email-e2ee-automatism-pre"/>
+      <separator class="thin"/>
+
+      <checkbox id="emailE2eeAutoEnable"
+                preference="mail.e2ee.auto_enable"
+                data-l10n-id="email-e2ee-auto-on"
+                oncommand="gPrivacyPane.updateE2eeCheckboxes();"/>
+      <checkbox id="emailE2eeAutoDisable"
+                preference="mail.e2ee.auto_disable"
+                data-l10n-id="email-e2ee-auto-off"
+                oncommand="gPrivacyPane.updateE2eeCheckboxes();"/>
+      <checkbox id="emailE2eeAutoDisableNotify"
+                preference="mail.e2ee.notify_on_auto_disable"
+                data-l10n-id="email-e2ee-auto-off-notify"
+                oncommand="gPrivacyPane.updateE2eeCheckboxes();"/>
+
+      <separator class="thin"/>
+      <description data-l10n-id="email-e2ee-automatism-post"/>
+    </html:fieldset>
+    </html:div>
+  </html:template>
diff --git a/comm/mail/components/preferences/privacy.js b/comm/mail/components/preferences/privacy.js
new file mode 100644
index 0000000000..2bb8cba6ad
--- /dev/null
+++ b/comm/mail/components/preferences/privacy.js
@@ -0,0 +1,562 @@
+/* -*- Mode: JavaScript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * 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";
+
+/* import-globals-from preferences.js */
+
+var { XPCOMUtils } = ChromeUtils.importESModule(
+  "resource://gre/modules/XPCOMUtils.sys.mjs"
+);
+
+ChromeUtils.defineESModuleGetters(this, {
+  LoginHelper: "resource://gre/modules/LoginHelper.sys.mjs",
+  OSKeyStore: "resource://gre/modules/OSKeyStore.sys.mjs",
+});
+
+const PREF_UPLOAD_ENABLED = "datareporting.healthreport.uploadEnabled";
+
+Preferences.addAll([
+  { id: "mail.spam.manualMark", type: "bool" },
+  { id: "mail.spam.manualMarkMode", type: "int" },
+  { id: "mail.spam.markAsReadOnSpam", type: "bool" },
+  { id: "mail.spam.logging.enabled", type: "bool" },
+  { id: "mail.phishing.detection.enabled", type: "bool" },
+  { id: "browser.safebrowsing.enabled", type: "bool" },
+  { id: "mailnews.downloadToTempFile", type: "bool" },
+  { id: "pref.privacy.disable_button.view_passwords", type: "bool" },
+  { id: "pref.privacy.disable_button.cookie_exceptions", type: "bool" },
+  { id: "pref.privacy.disable_button.view_cookies", type: "bool" },
+  {
+    id: "mailnews.message_display.disable_remote_image",
+    type: "bool",
+    inverted: "true",
+  },
+  { id: "places.history.enabled", type: "bool" },
+  { id: "network.cookie.cookieBehavior", type: "int" },
+  { id: "network.cookie.blockFutureCookies", type: "bool" },
+  { id: "privacy.donottrackheader.enabled", type: "bool" },
+  { id: "security.default_personal_cert", type: "string" },
+  { id: "security.disable_button.openCertManager", type: "bool" },
+  { id: "security.disable_button.openDeviceManager", type: "bool" },
+  { id: "security.OCSP.enabled", type: "int" },
+  { id: "mail.e2ee.auto_enable", type: "bool" },
+  { id: "mail.e2ee.auto_disable", type: "bool" },
+  { id: "mail.e2ee.notify_on_auto_disable", type: "bool" },
+]);
+
+if (AppConstants.MOZ_DATA_REPORTING) {
+  Preferences.addAll([
+    // Preference instances for prefs that we need to monitor while the page is open.
+    { id: PREF_UPLOAD_ENABLED, type: "bool" },
+  ]);
+}
+
+// Data Choices tab
+if (AppConstants.MOZ_CRASHREPORTER) {
+  Preferences.add({
+    id: "browser.crashReports.unsubmittedCheck.autoSubmit2",
+    type: "bool",
+  });
+}
+
+function setEventListener(aId, aEventType, aCallback) {
+  document
+    .getElementById(aId)
+    .addEventListener(aEventType, aCallback.bind(gPrivacyPane));
+}
+
+var gPrivacyPane = {
+  init() {
+    this.updateManualMarkMode(Preferences.get("mail.spam.manualMark").value);
+    this.updateJunkLogButton(
+      Preferences.get("mail.spam.logging.enabled").value
+    );
+
+    this._initMasterPasswordUI();
+
+    if (AppConstants.MOZ_DATA_REPORTING) {
+      this.initDataCollection();
+      if (AppConstants.MOZ_CRASHREPORTER) {
+        this.initSubmitCrashes();
+      }
+      this.initSubmitHealthReport();
+      setEventListener(
+        "submitHealthReportBox",
+        "command",
+        gPrivacyPane.updateSubmitHealthReport
+      );
+      setEventListener(
+        "telemetryDataDeletionLearnMore",
+        "command",
+        gPrivacyPane.showDataDeletion
+      );
+    }
+
+    this.readAcceptCookies();
+    let element = document.getElementById("acceptCookies");
+    Preferences.addSyncFromPrefListener(element, () =>
+      this.readAcceptCookies()
+    );
+    Preferences.addSyncToPrefListener(element, () => this.writeAcceptCookies());
+
+    element = document.getElementById("acceptThirdPartyMenu");
+    Preferences.addSyncFromPrefListener(element, () =>
+      this.readAcceptThirdPartyCookies()
+    );
+    Preferences.addSyncToPrefListener(element, () =>
+      this.writeAcceptThirdPartyCookies()
+    );
+
+    element = document.getElementById("enableOCSP");
+    Preferences.addSyncFromPrefListener(element, () => this.readEnableOCSP());
+    Preferences.addSyncToPrefListener(element, () => this.writeEnableOCSP());
+
+    this.initE2eeCheckboxes();
+  },
+
+  /**
+   * Reload the current message after a preference affecting the view
+   * has been changed.
+   */
+  reloadMessageInOpener() {
+    if (window.opener && typeof window.opener.ReloadMessage == "function") {
+      window.opener.ReloadMessage();
+    }
+  },
+
+  /**
+   * Reads the network.cookie.cookieBehavior preference value and
+   * enables/disables the rest of the cookie UI accordingly, returning true
+   * if cookies are enabled.
+   */
+  readAcceptCookies() {
+    let pref = Preferences.get("network.cookie.cookieBehavior");
+    let exceptionsButton = document.getElementById("cookieExceptions");
+    let acceptThirdPartyLabel = document.getElementById(
+      "acceptThirdPartyLabel"
+    );
+    let acceptThirdPartyMenu = document.getElementById("acceptThirdPartyMenu");
+    let showCookiesButton = document.getElementById("showCookiesButton");
+
+    // enable the rest of the UI for anything other than "disable all cookies"
+    let acceptCookies = pref.value != 2;
+    let cookieBehaviorLocked = Services.prefs.prefIsLocked(
+      "network.cookie.cookieBehavior"
+    );
+
+    exceptionsButton.disabled = cookieBehaviorLocked;
+    acceptThirdPartyLabel.disabled = acceptThirdPartyMenu.disabled =
+      !acceptCookies || cookieBehaviorLocked;
+    showCookiesButton.disabled = cookieBehaviorLocked;
+
+    return acceptCookies;
+  },
+
+  /**
+   * Enables/disables the "keep until" label and menulist in response to the
+   * "accept cookies" checkbox being checked or unchecked.
+   *
+   * @returns 0 if cookies are accepted, 2 if they are not;
+   *         the value network.cookie.cookieBehavior should get
+   */
+  writeAcceptCookies() {
+    let accept = document.getElementById("acceptCookies");
+    let acceptThirdPartyMenu = document.getElementById("acceptThirdPartyMenu");
+    // if we're enabling cookies, automatically select 'accept third party always'
+    if (accept.checked) {
+      acceptThirdPartyMenu.selectedIndex = 0;
+    }
+
+    return accept.checked ? 0 : 2;
+  },
+
+  /**
+   * Displays fine-grained, per-site preferences for cookies.
+   */
+  showCookieExceptions() {
+    let bundle = document.getElementById("bundlePreferences");
+    let params = {
+      blockVisible: true,
+      sessionVisible: true,
+      allowVisible: true,
+      prefilledHost: "",
+      permissionType: "cookie",
+      windowTitle: bundle.getString("cookiepermissionstitle"),
+      introText: bundle.getString("cookiepermissionstext"),
+    };
+    gSubDialog.open(
+      "chrome://messenger/content/preferences/permissions.xhtml",
+      undefined,
+      params
+    );
+  },
+
+  /**
+   * Displays all the user's cookies in a dialog.
+   */
+  showCookies(aCategory) {
+    gSubDialog.open("chrome://messenger/content/preferences/cookies.xhtml");
+  },
+
+  /**
+   * Converts between network.cookie.cookieBehavior and the third-party cookie UI
+   */
+  readAcceptThirdPartyCookies() {
+    let pref = Preferences.get("network.cookie.cookieBehavior");
+    switch (pref.value) {
+      case 0:
+        return "always";
+      case 1:
+        return "never";
+      case 2:
+        return "never";
+      case 3:
+        return "visited";
+      default:
+        return undefined;
+    }
+  },
+
+  writeAcceptThirdPartyCookies() {
+    let accept = document.getElementById("acceptThirdPartyMenu").selectedItem;
+    switch (accept.value) {
+      case "always":
+        return 0;
+      case "visited":
+        return 3;
+      case "never":
+        return 1;
+      default:
+        return undefined;
+    }
+  },
+
+  /**
+   * Displays fine-grained, per-site preferences for remote content.
+   * We use the "image" type for that, but it can also be stylesheets or
+   * iframes.
+   */
+  showRemoteContentExceptions() {
+    let bundle = document.getElementById("bundlePreferences");
+    let params = {
+      blockVisible: true,
+      sessionVisible: false,
+      allowVisible: true,
+      prefilledHost: "",
+      permissionType: "image",
+      windowTitle: bundle.getString("imagepermissionstitle"),
+      introText: bundle.getString("imagepermissionstext"),
+    };
+    gSubDialog.open(
+      "chrome://messenger/content/preferences/permissions.xhtml",
+      undefined,
+      params
+    );
+  },
+  updateManualMarkMode(aEnableRadioGroup) {
+    document.getElementById("manualMarkMode").disabled = !aEnableRadioGroup;
+  },
+
+  updateJunkLogButton(aEnableButton) {
+    document.getElementById("openJunkLogButton").disabled = !aEnableButton;
+  },
+
+  openJunkLog() {
+    // The junk log dialog can't work as a sub-dialog, because that means
+    // loading it in a browser, and we can't load a chrome: page containing a
+    // file: page in a browser. Open it as a real dialog instead.
+    window.browsingContext.topChromeWindow.openDialog(
+      "chrome://messenger/content/junkLog.xhtml"
+    );
+  },
+
+  resetTrainingData() {
+    // make sure the user really wants to do this
+    var bundle = document.getElementById("bundlePreferences");
+    var title = bundle.getString("confirmResetJunkTrainingTitle");
+    var text = bundle.getString("confirmResetJunkTrainingText");
+
+    // if the user says no, then just fall out
+    if (!Services.prompt.confirm(window, title, text)) {
+      return;
+    }
+
+    // otherwise go ahead and remove the training data
+    MailServices.junk.resetTrainingData();
+  },
+
+  /**
+   * Initializes primary password UI: the "use primary password" checkbox, selects
+   * the primary password button to show, and enables/disables it as necessary.
+   * The primary password is controlled by various bits of NSS functionality,
+   * so the UI for it can't be controlled by the normal preference bindings.
+   */
+  _initMasterPasswordUI() {
+    var noMP = !LoginHelper.isPrimaryPasswordSet();
+
+    var button = document.getElementById("changeMasterPassword");
+    button.disabled = noMP;
+
+    var checkbox = document.getElementById("useMasterPassword");
+    checkbox.checked = !noMP;
+    checkbox.disabled =
+      (noMP && !Services.policies.isAllowed("createMasterPassword")) ||
+      (!noMP && !Services.policies.isAllowed("removeMasterPassword"));
+  },
+
+  /**
+   * Enables/disables the primary password button depending on the state of the
+   * "use primary password" checkbox, and prompts for primary password removal
+   * if one is set.
+   */
+  async updateMasterPasswordButton() {
+    var checkbox = document.getElementById("useMasterPassword");
+    var button = document.getElementById("changeMasterPassword");
+    button.disabled = !checkbox.checked;
+
+    // unchecking the checkbox should try to immediately remove the master
+    // password, because it's impossible to non-destructively remove the master
+    // password used to encrypt all the passwords without providing it (by
+    // design), and it would be extremely odd to pop up that dialog when the
+    // user closes the prefwindow and saves his settings
+    if (!checkbox.checked) {
+      await this._removeMasterPassword();
+    } else {
+      await this.changeMasterPassword();
+    }
+
+    this._initMasterPasswordUI();
+  },
+
+  /**
+   * Displays the "remove primary password" dialog to allow the user to remove
+   * the current primary password.  When the dialog is dismissed, primary password
+   * UI is automatically updated.
+   */
+  async _removeMasterPassword() {
+    var secmodDB = Cc["@mozilla.org/security/pkcs11moduledb;1"].getService(
+      Ci.nsIPKCS11ModuleDB
+    );
+    if (secmodDB.isFIPSEnabled) {
+      let title = document.getElementById("fips-title").textContent;
+      let desc = document.getElementById("fips-desc").textContent;
+      Services.prompt.alert(window, title, desc);
+      this._initMasterPasswordUI();
+    } else {
+      gSubDialog.open("chrome://mozapps/content/preferences/removemp.xhtml", {
+        closingCallback: this._initMasterPasswordUI.bind(this),
+      });
+    }
+    this._initMasterPasswordUI();
+  },
+
+  /**
+   * Displays a dialog in which the primary password may be changed.
+   */
+  async changeMasterPassword() {
+    // OS reauthenticate functionality is not available on Linux yet (bug 1527745)
+    if (
+      !LoginHelper.isPrimaryPasswordSet() &&
+      Services.prefs.getBoolPref("signon.management.page.os-auth.enabled") &&
+      AppConstants.platform != "linux"
+    ) {
+      let messageId =
+        "primary-password-os-auth-dialog-message-" + AppConstants.platform;
+      let [messageText, captionText] = await document.l10n.formatMessages([
+        {
+          id: messageId,
+        },
+        {
+          id: "master-password-os-auth-dialog-caption",
+        },
+      ]);
+      let win = Services.wm.getMostRecentWindow("");
+      let loggedIn = await OSKeyStore.ensureLoggedIn(
+        messageText.value,
+        captionText.value,
+        win,
+        false
+      );
+      if (!loggedIn.authenticated) {
+        return;
+      }
+    }
+
+    gSubDialog.open("chrome://mozapps/content/preferences/changemp.xhtml", {
+      closingCallback: this._initMasterPasswordUI.bind(this),
+    });
+  },
+
+  /**
+   * Shows the sites where the user has saved passwords and the associated
+   * login information.
+   */
+  showPasswords() {
+    gSubDialog.open(
+      "chrome://messenger/content/preferences/passwordManager.xhtml"
+    );
+  },
+
+  updateDownloadedPhishingListState() {
+    document.getElementById("useDownloadedList").disabled =
+      !document.getElementById("enablePhishingDetector").checked;
+  },
+
+  /**
+   * Display the user's certificates and associated options.
+   */
+  showCertificates() {
+    gSubDialog.open("chrome://pippki/content/certManager.xhtml");
+  },
+
+  /**
+   * security.OCSP.enabled is an integer value for legacy reasons.
+   * A value of 1 means OCSP is enabled. Any other value means it is disabled.
+   */
+  readEnableOCSP() {
+    var preference = Preferences.get("security.OCSP.enabled");
+    // This is the case if the preference is the default value.
+    if (preference.value === undefined) {
+      return true;
+    }
+    return preference.value == 1;
+  },
+
+  /**
+   * See documentation for readEnableOCSP.
+   */
+  writeEnableOCSP() {
+    var checkbox = document.getElementById("enableOCSP");
+    return checkbox.checked ? 1 : 0;
+  },
+
+  /**
+   * Display a dialog from which the user can manage his security devices.
+   */
+  showSecurityDevices() {
+    gSubDialog.open("chrome://pippki/content/device_manager.xhtml");
+  },
+
+  /**
+   * Displays the learn more health report page when a user opts out of data collection.
+   */
+  showDataDeletion() {
+    let url =
+      Services.urlFormatter.formatURLPref("app.support.baseURL") +
+      "telemetry-clientid";
+    window.open(url, "_blank");
+  },
+
+  initDataCollection() {
+    this._setupLearnMoreLink(
+      "toolkit.datacollection.infoURL",
+      "dataCollectionPrivacyNotice"
+    );
+  },
+
+  initSubmitCrashes() {
+    this._setupLearnMoreLink(
+      "toolkit.crashreporter.infoURL",
+      "crashReporterLearnMore"
+    );
+  },
+
+  /**
+   * Set up or hide the Learn More links for various data collection options
+   */
+  _setupLearnMoreLink(pref, element) {
+    // set up the Learn More link with the correct URL
+    let url = Services.urlFormatter.formatURLPref(pref);
+    let el = document.getElementById(element);
+
+    if (url) {
+      el.setAttribute("href", url);
+    } else {
+      el.setAttribute("hidden", "true");
+    }
+  },
+
+  /**
+   * Initialize the health report service reference and checkbox.
+   */
+  initSubmitHealthReport() {
+    this._setupLearnMoreLink(
+      "datareporting.healthreport.infoURL",
+      "FHRLearnMore"
+    );
+
+    let checkbox = document.getElementById("submitHealthReportBox");
+
+    // Telemetry is only sending data if MOZ_TELEMETRY_REPORTING is defined.
+    // We still want to display the preferences panel if that's not the case, but
+    // we want it to be disabled and unchecked.
+    if (
+      Services.prefs.prefIsLocked(PREF_UPLOAD_ENABLED) ||
+      !AppConstants.MOZ_TELEMETRY_REPORTING
+    ) {
+      checkbox.setAttribute("disabled", "true");
+      return;
+    }
+
+    checkbox.checked =
+      Services.prefs.getBoolPref(PREF_UPLOAD_ENABLED) &&
+      AppConstants.MOZ_TELEMETRY_REPORTING;
+  },
+
+  /**
+   * Update the health report preference with state from checkbox.
+   */
+  updateSubmitHealthReport() {
+    let checkbox = document.getElementById("submitHealthReportBox");
+
+    Services.prefs.setBoolPref(PREF_UPLOAD_ENABLED, checkbox.checked);
+
+    // If allow telemetry is checked, hide the box saying you're no longer
+    // allowing it.
+    document.getElementById("telemetry-container").hidden = checkbox.checked;
+  },
+
+  initE2eeCheckboxes() {
+    let on = document.getElementById("emailE2eeAutoEnable");
+    let off = document.getElementById("emailE2eeAutoDisable");
+    let notify = document.getElementById("emailE2eeAutoDisableNotify");
+
+    on.checked = Preferences.get("mail.e2ee.auto_enable").value;
+    off.checked = Preferences.get("mail.e2ee.auto_disable").value;
+    notify.checked = Preferences.get("mail.e2ee.notify_on_auto_disable").value;
+
+    if (!on.checked) {
+      off.disabled = true;
+      notify.disabled = true;
+    } else {
+      off.disabled = false;
+      notify.disabled = !off.checked;
+    }
+  },
+
+  updateE2eeCheckboxes() {
+    let on = document.getElementById("emailE2eeAutoEnable");
+    let off = document.getElementById("emailE2eeAutoDisable");
+    let notify = document.getElementById("emailE2eeAutoDisableNotify");
+
+    if (!on.checked) {
+      off.disabled = true;
+      notify.disabled = true;
+    } else {
+      off.disabled = false;
+      notify.disabled = !off.checked;
+    }
+  },
+};
+
+Preferences.get("mailnews.message_display.disable_remote_image").on(
+  "change",
+  gPrivacyPane.reloadMessageInOpener
+);
+Preferences.get("mail.phishing.detection.enabled").on(
+  "change",
+  gPrivacyPane.reloadMessageInOpener
+);
diff --git a/comm/mail/components/preferences/receipts.js b/comm/mail/components/preferences/receipts.js
new file mode 100644
index 0000000000..748a65d127
--- /dev/null
+++ b/comm/mail/components/preferences/receipts.js
@@ -0,0 +1,38 @@
+/* -*- Mode: Javascript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * 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-globals-from ../../../../toolkit/content/preferencesBindings.js */
+
+Preferences.addAll([
+  { id: "mail.receipt.request_return_receipt_on", type: "bool" },
+  { id: "mail.incorporate.return_receipt", type: "int" },
+  { id: "mail.mdn.report.enabled", type: "bool" },
+  { id: "mail.mdn.report.not_in_to_cc", type: "int" },
+  { id: "mail.mdn.report.outside_domain", type: "int" },
+  { id: "mail.mdn.report.other", type: "int" },
+]);
+
+/**
+ * Enables/disables the labels and menulists depending whether
+ * sending of return receipts is enabled.
+ */
+function enableDisableAllowedReceipts() {
+  let enable = document.getElementById("receiptSend").value === "true";
+  enableElement(document.getElementById("notInToCcLabel"), enable);
+  enableElement(document.getElementById("notInToCcPref"), enable);
+  enableElement(document.getElementById("outsideDomainLabel"), enable);
+  enableElement(document.getElementById("outsideDomainPref"), enable);
+  enableElement(document.getElementById("otherCasesLabel"), enable);
+  enableElement(document.getElementById("otherCasesPref"), enable);
+}
+
+/**
+ * Set disabled state of aElement, unless its associated pref is locked.
+ */
+function enableElement(aElement, aEnable) {
+  let pref = aElement.getAttribute("preference");
+  let prefIsLocked = pref ? Preferences.get(pref).locked : false;
+  aElement.disabled = !aEnable || prefIsLocked;
+}
diff --git a/comm/mail/components/preferences/receipts.xhtml b/comm/mail/components/preferences/receipts.xhtml
new file mode 100644
index 0000000000..32f8a7237d
--- /dev/null
+++ b/comm/mail/components/preferences/receipts.xhtml
@@ -0,0 +1,120 @@
+<?xml version="1.0"?>
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+
+<!DOCTYPE window>
+
+<window
+  type="child"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+  xmlns:html="http://www.w3.org/1999/xhtml"
+  data-l10n-id="receipts-dialog-window"
+  onload="enableDisableAllowedReceipts();"
+>
+  <dialog id="ReturnReceiptsDialog" dlgbuttons="accept,cancel">
+    <script src="chrome://global/content/preferencesBindings.js" />
+    <script src="chrome://messenger/content/preferences/receipts.js" />
+
+    <linkset>
+      <html:link rel="localization" href="messenger/preferences/receipts.ftl" />
+    </linkset>
+
+    <vbox id="returnReceiptSettings" align="start">
+      <checkbox
+        id="alwaysRequest"
+        data-l10n-id="return-receipt-checkbox-control"
+        preference="mail.receipt.request_return_receipt_on"
+      />
+    </vbox>
+
+    <separator class="thin" />
+    <separator class="groove" />
+    <separator class="thin" />
+
+    <label control="receiptFolder" data-l10n-id="receipt-arrive-label" />
+    <radiogroup
+      id="receiptFolder"
+      class="indent"
+      preference="mail.incorporate.return_receipt"
+    >
+      <radio value="0" data-l10n-id="receipt-leave-radio-control" />
+      <radio value="1" data-l10n-id="receipt-move-radio-control" />
+    </radiogroup>
+
+    <separator class="thin" />
+    <separator class="groove" />
+    <separator class="thin" />
+
+    <label control="receiptSend" data-l10n-id="receipt-request-label" />
+    <radiogroup
+      id="receiptSend"
+      class="indent"
+      preference="mail.mdn.report.enabled"
+      oncommand="enableDisableAllowedReceipts();"
+    >
+      <radio value="false" data-l10n-id="receipt-return-never-radio-control" />
+      <radio value="true" data-l10n-id="receipt-return-some-radio-control" />
+
+      <vbox class="indent">
+        <hbox align="center">
+          <hbox flex="1">
+            <label
+              id="notInToCcLabel"
+              data-l10n-id="receipt-not-to-cc-label"
+              control="notInToCcPref"
+            />
+          </hbox>
+          <menulist
+            id="notInToCcPref"
+            preference="mail.mdn.report.not_in_to_cc"
+          >
+            <menupopup>
+              <menuitem value="0" data-l10n-id="receipt-send-never-label" />
+              <menuitem value="1" data-l10n-id="receipt-send-always-label" />
+              <menuitem value="2" data-l10n-id="receipt-send-ask-label" />
+            </menupopup>
+          </menulist>
+        </hbox>
+        <hbox align="center">
+          <hbox flex="1">
+            <label
+              id="outsideDomainLabel"
+              data-l10n-id="sender-outside-domain-label"
+              control="outsideDomainPref"
+            />
+          </hbox>
+          <menulist
+            id="outsideDomainPref"
+            preference="mail.mdn.report.outside_domain"
+          >
+            <menupopup>
+              <menuitem value="0" data-l10n-id="receipt-send-never-label" />
+              <menuitem value="1" data-l10n-id="receipt-send-always-label" />
+              <menuitem value="2" data-l10n-id="receipt-send-ask-label" />
+            </menupopup>
+          </menulist>
+        </hbox>
+        <hbox align="center">
+          <hbox flex="1">
+            <label
+              id="otherCasesLabel"
+              data-l10n-id="other-cases-text-label"
+              control="otherCasesPref"
+            />
+          </hbox>
+          <menulist id="otherCasesPref" preference="mail.mdn.report.other">
+            <menupopup>
+              <menuitem value="0" data-l10n-id="receipt-send-never-label" />
+              <menuitem value="1" data-l10n-id="receipt-send-always-label" />
+              <menuitem value="2" data-l10n-id="receipt-send-ask-label" />
+            </menupopup>
+          </menulist>
+        </hbox>
+      </vbox>
+    </radiogroup>
+    <separator />
+  </dialog>
+</window>
diff --git a/comm/mail/components/preferences/searchResults.inc.xhtml b/comm/mail/components/preferences/searchResults.inc.xhtml
new file mode 100644
index 0000000000..9fa66a27c5
--- /dev/null
+++ b/comm/mail/components/preferences/searchResults.inc.xhtml
@@ -0,0 +1,24 @@
+<!-- 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/. -->
+
+  <hbox id="header-searchResults"
+        class="subcategory"
+        hidden="true"
+        data-hidden-from-search="true"
+        data-category="paneSearchResults">
+     <html:h1 data-l10n-id="search-results-header"/>
+   </hbox>
+   <groupbox id="no-results-message"
+             data-hidden-from-search="true"
+             data-category="paneSearchResults"
+             hidden="true">
+     <vbox class="no-results-container">
+       <label id="sorry-message" data-l10n-id="search-results-empty-message2">
+         <html:span data-l10n-name="query" id="sorry-message-query"/>
+       </label>
+       <label id="need-help" data-l10n-id="search-results-help-link">
+         <html:a class="text-link" data-l10n-name="url" target="_blank"></html:a>
+       </label>
+     </vbox>
+  </groupbox>
diff --git a/comm/mail/components/preferences/sync.inc.xhtml b/comm/mail/components/preferences/sync.inc.xhtml
new file mode 100644
index 0000000000..a101d4359b
--- /dev/null
+++ b/comm/mail/components/preferences/sync.inc.xhtml
@@ -0,0 +1,239 @@
+# 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/.
+<script src="chrome://messenger/content/preferences/sync.js"/>
+
+<html:template id="paneSync">
+  <html:div id="syncPaneCategory"
+            class="subcategory"
+            data-category="paneSync"
+            xmlns="http://www.w3.org/1999/xhtml">
+    <h1 data-l10n-id="sync-pane-header"></h1>
+
+    <section id="noFxaAccount" hidden="hidden">
+      <div id="noFxaInfo">
+        <h2 id="noFxaCaption" data-l10n-id="sync-signedout-caption"></h2>
+        <p id="noFxaDescription"
+           data-l10n-id="sync-signedout-description">
+        </p>
+        <button id="noFxaSignIn"
+                class="primary"
+                type="button"
+                data-l10n-id="sync-signedout-account-signin-btn">
+        </button>
+      </div>
+      <img id="noFxaSyncIllustration"
+           src="chrome://messenger/skin/illustrations/sync-devices.svg"
+           alt=""/>
+    </section>
+
+    <section id="hasFxaAccount" hidden="hidden">
+      <!-- Account NOT Verified -->
+      <section id="fxaLoginUnverified"
+               class="sync-account-section"
+               hidden="hidden">
+        <div id="photoDisplay">
+          <img class="contact-photo" src="" alt="" />
+        </div>
+        <div id="fxaLoginUnverifiedInfo">
+          <span id="fxaAccountMailNotVerified"
+                data-l10n-id="sync-pane-email-not-verified"
+                data-l10n-args='{"userEmail": ""}'>
+          </span>
+          <div id="fxaUnverifiedButtonOptions">
+            <button id="fxaResendVerification"
+                    class="place-self-end primary"
+                    data-l10n-id="sync-pane-resend-verification"
+                    type="button">
+            </button>
+            <button id="fxaUnverifiedRemoveAccount"
+                    class="place-self-end"
+                    data-l10n-id="sync-pane-remove-account"
+                    type="button">
+            </button>
+          </div>
+        </div>
+      </section>
+
+      <!-- Server Rejected Credientials -->
+      <section id="fxaLoginRejected"
+               class="sync-account-section"
+               hidden="hidden">
+        <div id="photoDisplay">
+          <img class="contact-photo" src="" alt="" />
+        </div>
+        <div id="fxaLoginRejectedInfo">
+          <span id="fxaAccountLoginRejected"
+                data-l10n-id="sync-signedin-login-failure"
+                data-l10n-args='{"userEmail": ""}'>
+          </span>
+          <div id="fxaRejectedButtonOptions">
+            <button id="fxaRejectedSignIn"
+                    class="place-self-end primary"
+                    data-l10n-id="sync-pane-sign-in"
+                    type="button">
+            </button>
+            <button id="fxaRejectedRemoveAccount"
+                    class="place-self-end"
+                    data-l10n-id="sync-pane-remove-account"
+                    type="button">
+            </button>
+          </div>
+        </div>
+      </section>
+
+      <!-- Account Verified -->
+      <section id="fxaLoginVerified"
+               class="sync-account-section"
+               hidden="hidden">
+        <div id="photoInput">
+          <button type="button" id="photoButton"
+                  class="plain-button"
+                  data-l10n-id="sync-pane-edit-photo">
+            <img id="fxaAvatar" class="contact-photo" src="" alt="" />
+            <div id="photoOverlay"></div>
+          </button>
+        </div>
+        <div id="fxaAccountInfo">
+          <span id="fxaDisplayName"></span>
+          <span id="fxaEmailAddress"></span>
+          <a id="verifiedManage" href="#" data-l10n-id="sync-pane-manage-account"></a>
+        </div>
+        <button id="fxaAccountSignOut"
+                class="place-self-end"
+                data-l10n-id="sync-pane-sign-out"
+                type="button">
+        </button>
+      </section>
+
+      <fieldset id="fxaDeviceInfo" hidden="hidden">
+        <legend data-l10n-id="sync-pane-device-name-title"></legend>
+        <input id="fxaDeviceNameInput" type="text" readonly="readonly"/>
+        <!-- Hidden by default, shown if #fxaDeviceNameChangeDeviceName is pressed -->
+        <button id="fxaDeviceNameCancel"
+                class="place-self-end"
+                data-l10n-id="sync-pane-cancel"
+                type="button"
+                hidden="hidden">
+        </button>
+        <button id="fxaDeviceNameSave"
+                class="place-self-end"
+                data-l10n-id="sync-pane-save"
+                type="button"
+                hidden="hidden">
+        </button>
+        <!-- Disappear once pressed to allow the previous two buttons to take
+           - its place, reappears once cancel or save is pressed -->
+        <button id="fxaDeviceNameChangeDeviceName"
+                class="place-self-end needs-account-ready"
+                data-l10n-id="sync-pane-change-device-name"
+                type="button">
+        </button>
+      </fieldset>
+
+      <div id="syncConnected" class="sync-section" hidden="hidden">
+        <div id="showSyncedHeader">
+          <h2 class="sync-header"
+              data-l10n-id="sync-pane-show-synced-header-on">
+          </h2>
+          <button id="syncShowSyncedSyncNow"
+                  class="place-self-end needs-account-ready"
+                  data-l10n-id="sync-pane-sync-now"
+                  type="button">
+          </button>
+        </div>
+
+        <div class="sync-panel">
+          <div id="showSyncedListHeader">
+            <h3 id="showSyncedListHeading" data-l10n-id="show-synced-list-heading"></h3>
+            <a id="enginesLearnMore" href="#" data-l10n-id="show-synced-learn-more"></a>
+          </div>
+
+          <ul id="showSyncedList" class="synced-list">
+            <!-- For when we get per-account controls: -->
+            <!-- <li id="showSyncAccount">
+              <span id="showSyncAccountLabel"
+                    class="synced-item"
+                    data-l10n-id="show-synced-item-account">
+              </span>
+              <div id="syncedAccounts">
+
+                <div class="synced-account">
+                  <h4 class="synced-account-name">nemo@thunderbird.net</h4>
+                  <ul class="synced-list">
+                    <li class="synced-item synced-account-server-config"
+                        data-l10n-id="synced-acount-item-server-config">
+                    </li>
+                    <li class="synced-item synced-account-filters"
+                        data-l10n-id="synced-acount-item-filters">
+                    </li>
+                    <li class="synced-item synced-account-keys"
+                        data-l10n-id="synced-acount-item-keys">
+                    </li>
+                  </ul>
+                </div>
+
+                <div class="synced-account">
+                  <h4 class="synced-account-name">example@example.com</h4>
+                  <ul class="synced-list">
+                    <li class="synced-item synced-account-server-config"
+                        data-l10n-id="synced-acount-item-server-config">
+                    </li>
+                    <li class="synced-item synced-account-filters"
+                        data-l10n-id="synced-acount-item-filters">
+                    </li>
+                    <li class="synced-item synced-account-keys"
+                        data-l10n-id="synced-acount-item-keys">
+                    </li>
+                  </ul>
+                </div>
+
+              </div>
+            </li> -->
+            <li id="showSyncAccount"
+                class="synced-item"
+                data-l10n-id="show-synced-item-account">
+            </li>
+            <li id="showSyncIdentity"
+                class="synced-item"
+                data-l10n-id="show-synced-item-identity">
+            </li>
+            <li id="showSyncAddress"
+                class="synced-item"
+                data-l10n-id="show-synced-item-address">
+            </li>
+            <li id="showSyncCalendar"
+                class="synced-item"
+                data-l10n-id="show-synced-item-calendar">
+            </li>
+            <li id="showSyncPasswords"
+                class="synced-item"
+                data-l10n-id="show-synced-item-passwords">
+            </li>
+          </ul>
+
+          <button id="syncChangeOptions"
+                  class="place-self-end primary"
+                  data-l10n-id="show-synced-change"
+                  type="button">
+          </button>
+        </div>
+      </div>
+
+      <div id="syncDisconnected" class="sync-section" hidden="hidden">
+        <h2 class="sync-header"
+            data-l10n-id="sync-pane-show-synced-header-off">
+        </h2>
+
+        <div class="sync-panel">
+          <p data-l10n-id="sync-disconnected-text"></p>
+          <button id="syncSetup"
+                  class="place-self-start needs-account-ready"
+                  data-l10n-id="sync-disconnected-turn-on-sync"
+                  type="button">
+          </button>
+        </div>
+      </div>
+    </section>
+  </html:div>
+</html:template>
diff --git a/comm/mail/components/preferences/sync.js b/comm/mail/components/preferences/sync.js
new file mode 100644
index 0000000000..d8336c6e23
--- /dev/null
+++ b/comm/mail/components/preferences/sync.js
@@ -0,0 +1,377 @@
+/* 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-globals-from preferences.js */
+
+ChromeUtils.defineESModuleGetters(this, {
+  UIState: "resource://services-sync/UIState.sys.mjs",
+  Weave: "resource://services-sync/main.sys.mjs",
+});
+
+var { FxAccounts, getFxAccountsSingleton } = ChromeUtils.importESModule(
+  "resource://gre/modules/FxAccounts.sys.mjs"
+);
+var fxAccounts = getFxAccountsSingleton();
+
+var gSyncPane = {
+  init() {
+    this._setupEventListeners();
+    this.setupEnginesUI();
+
+    Weave.Svc.Obs.add(UIState.ON_UPDATE, this.updateWeavePrefs, this);
+
+    window.addEventListener("unload", () => {
+      Weave.Svc.Obs.remove(UIState.ON_UPDATE, this.updateWeavePrefs, this);
+    });
+
+    let cachedComputerName = Services.prefs.getStringPref(
+      "identity.fxaccounts.account.device.name",
+      ""
+    );
+    if (cachedComputerName) {
+      this._populateComputerName(cachedComputerName);
+    }
+
+    this.updateWeavePrefs();
+  },
+
+  /**
+   * Update the UI based on the current state.
+   */
+  updateWeavePrefs() {
+    let state = UIState.get();
+
+    let noFxaAccount = document.getElementById("noFxaAccount");
+    let hasFxaAccount = document.getElementById("hasFxaAccount");
+    if (state.status == UIState.STATUS_NOT_CONFIGURED) {
+      noFxaAccount.hidden = false;
+      hasFxaAccount.hidden = true;
+      return;
+    }
+    noFxaAccount.hidden = true;
+    hasFxaAccount.hidden = false;
+
+    let syncReady = false; // Is sync able to actually sync?
+    let fxaLoginUnverified = document.getElementById("fxaLoginUnverified");
+    let fxaLoginRejected = document.getElementById("fxaLoginRejected");
+    let fxaLoginVerified = document.getElementById("fxaLoginVerified");
+    if (state.status == UIState.STATUS_LOGIN_FAILED) {
+      fxaLoginUnverified.hidden = true;
+      fxaLoginRejected.hidden = false;
+      fxaLoginVerified.hidden = true;
+    } else if (state.status == UIState.STATUS_NOT_VERIFIED) {
+      fxaLoginUnverified.hidden = false;
+      fxaLoginRejected.hidden = true;
+      fxaLoginVerified.hidden = true;
+    } else {
+      fxaLoginUnverified.hidden = true;
+      fxaLoginRejected.hidden = true;
+      fxaLoginVerified.hidden = false;
+      syncReady = true;
+    }
+
+    this._populateComputerName(Weave.Service.clientsEngine.localName);
+    for (let elt of document.querySelectorAll(".needs-account-ready")) {
+      elt.disabled = !syncReady;
+    }
+
+    let syncConnected = document.getElementById("syncConnected");
+    let syncDisconnected = document.getElementById("syncDisconnected");
+    syncConnected.hidden = !syncReady || !state.syncEnabled;
+    syncDisconnected.hidden = !syncReady || state.syncEnabled;
+
+    document.l10n.setAttributes(
+      document.getElementById("fxaAccountMailNotVerified"),
+      "sync-pane-email-not-verified",
+      { userEmail: state.email }
+    );
+    document.l10n.setAttributes(
+      document.getElementById("fxaAccountLoginRejected"),
+      "sync-signedin-login-failure",
+      { userEmail: state.email }
+    );
+
+    document.getElementById("fxaAvatar").src =
+      state.avatarURL && !state.avatarIsDefault ? state.avatarURL : "";
+    document.getElementById("fxaDisplayName").textContent = state.displayName;
+    document.getElementById("fxaEmailAddress").textContent = state.email;
+
+    this._updateSyncNow(state.syncing);
+  },
+
+  _toggleComputerNameControls(editMode) {
+    let textbox = document.getElementById("fxaDeviceNameInput");
+    textbox.readOnly = !editMode;
+    document.getElementById("fxaDeviceNameChangeDeviceName").hidden = editMode;
+    document.getElementById("fxaDeviceNameCancel").hidden = !editMode;
+    document.getElementById("fxaDeviceNameSave").hidden = !editMode;
+  },
+
+  _focusComputerNameTextbox() {
+    let textbox = document.getElementById("fxaDeviceNameInput");
+    let valLength = textbox.value.length;
+    textbox.focus();
+    textbox.setSelectionRange(valLength, valLength);
+  },
+
+  _blurComputerNameTextbox() {
+    document.getElementById("fxaDeviceNameInput").blur();
+  },
+
+  _focusAfterComputerNameTextbox() {
+    // Focus the most appropriate element that's *not* the "computer name" box.
+    Services.focus.moveFocus(
+      window,
+      document.getElementById("fxaDeviceNameInput"),
+      Services.focus.MOVEFOCUS_FORWARD,
+      0
+    );
+  },
+
+  _updateComputerNameValue(save) {
+    if (save) {
+      let textbox = document.getElementById("fxaDeviceNameInput");
+      Weave.Service.clientsEngine.localName = textbox.value;
+    }
+    this._populateComputerName(Weave.Service.clientsEngine.localName);
+  },
+
+  _setupEventListeners() {
+    function setEventListener(id, eventType, callback) {
+      document
+        .getElementById(id)
+        .addEventListener(eventType, callback.bind(gSyncPane));
+    }
+
+    setEventListener("noFxaSignIn", "click", function () {
+      window.browsingContext.topChromeWindow.gSync.initFxA();
+      return false;
+    });
+    setEventListener(
+      "fxaResendVerification",
+      "click",
+      gSyncPane.verifyFirefoxAccount
+    );
+    setEventListener("fxaUnverifiedRemoveAccount", "click", function () {
+      /* No warning as account can't have previously synced. */
+      gSyncPane.unlinkFirefoxAccount(false);
+    });
+    setEventListener("fxaRejectedSignIn", "click", gSyncPane.reSignIn);
+    setEventListener("fxaRejectedRemoveAccount", "click", function () {
+      gSyncPane.unlinkFirefoxAccount(true);
+    });
+    setEventListener("photoButton", "click", function (event) {
+      window.browsingContext.topChromeWindow.gSync.openFxAAvatarPage(
+        "preferences"
+      );
+    });
+    setEventListener("verifiedManage", "click", function (event) {
+      window.browsingContext.topChromeWindow.gSync.openFxAManagePage(
+        "preferences"
+      );
+      event.preventDefault();
+      // Stop attempts to open this link in an external browser.
+      event.stopPropagation();
+    });
+    setEventListener("fxaAccountSignOut", "click", function () {
+      gSyncPane.unlinkFirefoxAccount(true);
+    });
+    setEventListener("fxaDeviceNameCancel", "click", function () {
+      // We explicitly blur the textbox because of bug 75324, then after
+      // changing the state of the buttons, force focus to whatever the focus
+      // manager thinks should be next (which on the mac, depends on an OSX
+      // keyboard access preference)
+      this._blurComputerNameTextbox();
+      this._toggleComputerNameControls(false);
+      this._updateComputerNameValue(false);
+      this._focusAfterComputerNameTextbox();
+    });
+    setEventListener("fxaDeviceNameSave", "click", function () {
+      // Work around bug 75324 - see above.
+      this._blurComputerNameTextbox();
+      this._toggleComputerNameControls(false);
+      this._updateComputerNameValue(true);
+      this._focusAfterComputerNameTextbox();
+    });
+    setEventListener("fxaDeviceNameChangeDeviceName", "click", function () {
+      this._toggleComputerNameControls(true);
+      this._focusComputerNameTextbox();
+    });
+    setEventListener("syncShowSyncedSyncNow", "click", function () {
+      // syncing can take a little time to send the "started" notification, so
+      // pretend we already got it.
+      this._updateSyncNow(true);
+      Weave.Service.sync({ why: "aboutprefs" });
+    });
+    setEventListener("enginesLearnMore", "click", function (event) {
+      // TODO: A real page.
+      window.browsingContext.topChromeWindow.openContentTab(
+        "https://example.org/?page=learnMore"
+      );
+      event.preventDefault();
+      // Stop attempts to open this link in an external browser.
+      event.stopPropagation();
+    });
+    setEventListener("syncChangeOptions", "click", function () {
+      gSyncPane._chooseWhatToSync(true);
+    });
+    setEventListener("syncSetup", "click", function () {
+      gSyncPane._chooseWhatToSync(false);
+    });
+  },
+
+  async _chooseWhatToSync(isAlreadySyncing) {
+    // Assuming another device is syncing and we're not, we update the engines
+    // selection so the correct checkboxes are pre-filled.
+    if (!isAlreadySyncing) {
+      try {
+        await Weave.Service.updateLocalEnginesState();
+      } catch (err) {
+        console.error("Error updating the local engines state", err);
+      }
+    }
+    let params = {};
+    if (isAlreadySyncing) {
+      // If we are already syncing then we also offer to disconnect.
+      params.disconnectFun = () => this.disconnectSync();
+    }
+    gSubDialog.open(
+      "chrome://messenger/content/preferences/syncDialog.xhtml",
+      {
+        features: "resizable=no",
+        closingCallback: event => {
+          if (!isAlreadySyncing && event.detail.button == "accept") {
+            // We weren't syncing but the user has accepted the dialog - so we
+            // want to start!
+            fxAccounts.telemetry
+              .recordConnection(["sync"], "ui")
+              .then(() => {
+                return Weave.Service.configure();
+              })
+              .catch(err => {
+                console.error("Failed to enable sync", err);
+              });
+          }
+        },
+      },
+      params
+    );
+  },
+
+  _updateSyncNow(syncing) {
+    let button = document.getElementById("syncShowSyncedSyncNow");
+    if (syncing) {
+      document.l10n.setAttributes(button, "sync-panel-sync-now-syncing");
+      button.disabled = true;
+    } else {
+      document.l10n.setAttributes(button, "sync-pane-sync-now");
+      button.disabled = false;
+    }
+  },
+
+  /**
+   * If connecting to Firefox Accounts failed, try again.
+   */
+  async reSignIn() {
+    // There's a bit of an edge-case here - we might be forcing reauth when we've
+    // lost the FxA account data - in which case we'll not get a URL as the re-auth
+    // URL embeds account info and the server endpoint complains if we don't
+    // supply it - so we just use the regular "sign in" URL in that case.
+    if (!(await FxAccounts.canConnectAccount())) {
+      return;
+    }
+
+    const url =
+      (await FxAccounts.config.promiseForceSigninURI("preferences")) ||
+      (await FxAccounts.config.promiseConnectAccountURI("preferences"));
+    window.browsingContext.topChromeWindow.openContentTab(url);
+  },
+
+  /**
+   * Send a confirmation email to the account's email address.
+   */
+  verifyFirefoxAccount() {
+    let onError = async () => {
+      let [title, body] = await document.l10n.formatValues([
+        "fxa-verification-not-sent-title",
+        "fxa-verification-not-sent-body",
+      ]);
+      new Notification(title, { body });
+    };
+
+    let onSuccess = async data => {
+      if (data) {
+        let [title, body] = await document.l10n.formatValues([
+          "fxa-verification-sent-title",
+          { id: "fxa-verification-sent-body", args: { userEmail: data.email } },
+        ]);
+        new Notification(title, { body });
+      } else {
+        onError();
+      }
+    };
+
+    fxAccounts
+      .resendVerificationEmail()
+      .then(() => fxAccounts.getSignedInUser(), onError)
+      .then(onSuccess, onError);
+  },
+
+  /**
+   * Disconnect the account, including everything linked.
+   *
+   * @param {boolean} confirm - If true, asks the user if they're sure.
+   */
+  unlinkFirefoxAccount(confirm) {
+    window.browsingContext.topChromeWindow.gSync.disconnect({ confirm });
+  },
+
+  /**
+   * Disconnect sync, leaving the FxA account connected.
+   */
+  disconnectSync() {
+    return window.browsingContext.topChromeWindow.gSync.disconnect({
+      confirm: true,
+      disconnectAccount: false,
+    });
+  },
+
+  _populateComputerName(value) {
+    let textbox = document.getElementById("fxaDeviceNameInput");
+    if (!textbox.hasAttribute("placeholder")) {
+      textbox.setAttribute(
+        "placeholder",
+        fxAccounts.device.getDefaultLocalName()
+      );
+    }
+    textbox.value = value;
+  },
+
+  /**
+   * Arranges to dynamically show or hide sync engine name elements based on
+   * the preferences used for the engines.
+   */
+  setupEnginesUI() {
+    let observe = (element, prefName) => {
+      element.hidden = !Services.prefs.getBoolPref(prefName, false);
+    };
+
+    let engineItems = {
+      showSyncAccount: "services.sync.engine.accounts",
+      showSyncIdentity: "services.sync.engine.identities",
+      showSyncAddress: "services.sync.engine.addressbooks",
+      showSyncCalendar: "services.sync.engine.calendars",
+      showSyncPasswords: "services.sync.engine.passwords",
+    };
+
+    for (let [id, prefName] of Object.entries(engineItems)) {
+      let obs = observe.bind(null, document.getElementById(id), prefName);
+      obs();
+      Services.prefs.addObserver(prefName, obs);
+      window.addEventListener("unload", () => {
+        Services.prefs.removeObserver(prefName, obs);
+      });
+    }
+  },
+};
diff --git a/comm/mail/components/preferences/syncDialog.js b/comm/mail/components/preferences/syncDialog.js
new file mode 100644
index 0000000000..6920a8aa59
--- /dev/null
+++ b/comm/mail/components/preferences/syncDialog.js
@@ -0,0 +1,38 @@
+/* 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 engineItems = {
+  configSyncAccount: "services.sync.engine.accounts",
+  configSyncAddress: "services.sync.engine.addressbooks",
+  configSyncCalendar: "services.sync.engine.calendars",
+  configSyncIdentity: "services.sync.engine.identities",
+  configSyncPasswords: "services.sync.engine.passwords",
+};
+
+window.addEventListener("load", function () {
+  for (let [id, prefName] of Object.entries(engineItems)) {
+    let element = document.getElementById(id);
+    element.checked = Services.prefs.getBoolPref(prefName, false);
+  }
+
+  let options = window.arguments[0];
+  if (options.disconnectFun) {
+    window.addEventListener("dialogextra2", function () {
+      options.disconnectFun().then(disconnected => {
+        if (disconnected) {
+          window.close();
+        }
+      });
+    });
+  } else {
+    document.querySelector("dialog").getButton("extra2").hidden = true;
+  }
+});
+
+window.addEventListener("dialogaccept", function () {
+  for (let [id, prefName] of Object.entries(engineItems)) {
+    let element = document.getElementById(id);
+    Services.prefs.setBoolPref(prefName, element.checked);
+  }
+});
diff --git a/comm/mail/components/preferences/syncDialog.xhtml b/comm/mail/components/preferences/syncDialog.xhtml
new file mode 100644
index 0000000000..ce035245ea
--- /dev/null
+++ b/comm/mail/components/preferences/syncDialog.xhtml
@@ -0,0 +1,210 @@
+<?xml version="1.0"?>
+<!-- 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/. -->
+
+<!DOCTYPE html>
+<html
+  xmlns="http://www.w3.org/1999/xhtml"
+  xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+>
+  <head>
+    <title data-l10n-id="config-sync-dailog-title"></title>
+
+    <link rel="stylesheet" href="chrome://global/skin/global.css" />
+    <link
+      rel="stylesheet"
+      href="chrome://messenger/skin/preferences/preferences.css"
+    />
+
+    <link rel="localization" href="messenger/preferences/preferences.ftl" />
+    <link rel="localization" href="messenger/preferences/sync-dialog.ftl" />
+
+    <script src="chrome://messenger/content/preferences/syncDialog.js"></script>
+  </head>
+  <body>
+    <xul:dialog
+      id="configSyncDialog"
+      buttons="accept,cancel,extra2"
+      style="min-width: 49em"
+      data-l10n-attrs="buttonlabelaccept, buttonaccesskeyaccept, buttonlabelextra2, buttonaccesskeyextra2"
+      data-l10n-id="sync-dialog"
+    >
+      <div id="configSyncDialogContent">
+        <ul id="configSyncList" class="config-list">
+          <li id="configAccountsContainer">
+            <div class="config-item">
+              <input
+                type="checkbox"
+                id="configSyncAccount"
+                name="configSynced"
+              />
+              <label
+                for="configSyncAccount"
+                id="configSyncAccountLabel"
+                data-l10n-id="show-synced-item-account"
+              >
+              </label>
+            </div>
+            <!-- For when we get per-account controls: -->
+            <!-- <div id="configAccounts">
+
+              <div class="synced-account">
+                <div class="config-item synced-account-name">
+                  <input type="checkbox"
+                         id="configSyncAccount_1"
+                         name="configSyncedAccounts"/>
+                  <label for="configSyncAccount_1">
+                    nemo@thunderbird.net
+                  </label>
+                </div>
+                <ul class="config-list">
+                  <li>
+                    <div class="config-item">
+                      <input type="checkbox"
+                             id="configSyncServer_1"
+                             name="configSyncedAccount_1"/>
+                      <label for="configSyncServer_1"
+                             class="synced-account-server-config"
+                             data-l10n-id="synced-acount-item-server-config">
+                      </label>
+                    </div>
+                  </li>
+                  <li>
+                    <div class="config-item">
+                      <input type="checkbox"
+                             id="configSyncFilters_1"
+                             name="configSyncedAccount_1"/>
+                      <label for="configSyncFilters_1"
+                             class="synced-account-filters"
+                             data-l10n-id="synced-acount-item-filters">
+                      </label>
+                    </div>
+                  </li>
+                  <li>
+                    <div class="config-item">
+                      <input type="checkbox"
+                             id="configSyncKeys_1"
+                             name="configSyncedAccount_1"/>
+                      <label for="configSyncKeys_1"
+                             class="synced-account-keys"
+                             data-l10n-id="synced-acount-item-keys">
+                      </label>
+                    </div>
+                  </li>
+                </ul>
+              </div>
+
+              <div class="synced-account">
+                <div class="config-item synced-account-name">
+                  <input type="checkbox"
+                         id="configSyncAccount_2"
+                         name="configSyncedAccounts"/>
+                  <label for="configSyncAccount_2">
+                    example@example.com
+                  </label>
+                </div>
+                <ul class="config-list">
+                  <li>
+                    <div class="config-item">
+                      <input type="checkbox"
+                             id="configSyncServer_2"
+                             name="configSyncedAccount_2"/>
+                      <label for="configSyncServer_2"
+                             class="synced-account-server-config"
+                             data-l10n-id="synced-acount-item-server-config">
+                      </label>
+                    </div>
+                  </li>
+                  <li>
+                    <div class="config-item">
+                      <input type="checkbox"
+                             id="configSyncFilters_2"
+                             name="configSyncedAccount_2"/>
+                      <label for="configSyncFilters_2"
+                             class="synced-account-filters"
+                             data-l10n-id="synced-acount-item-filters">
+                      </label>
+                    </div>
+                  </li>
+                  <li>
+                    <div class="config-item">
+                      <input type="checkbox"
+                             id="configSyncKeys_2"
+                             name="configSyncedAccount_2"/>
+                      <label for="configSyncKeys_2"
+                             class="synced-account-keys"
+                             data-l10n-id="synced-acount-item-keys">
+                      </label>
+                    </div>
+                  </li>
+                </ul>
+              </div>
+
+            </div> -->
+          </li>
+          <li>
+            <div class="config-item">
+              <input
+                type="checkbox"
+                id="configSyncIdentity"
+                name="configSynced"
+              />
+              <label
+                id="configSyncIdentityLabel"
+                for="configSyncIdentity"
+                data-l10n-id="show-synced-item-identity"
+              >
+              </label>
+            </div>
+          </li>
+          <li>
+            <div class="config-item">
+              <input
+                type="checkbox"
+                id="configSyncAddress"
+                name="configSynced"
+              />
+              <label
+                id="configSyncAddressLabel"
+                for="configSyncAddress"
+                data-l10n-id="show-synced-item-address"
+              >
+              </label>
+            </div>
+          </li>
+          <li>
+            <div class="config-item">
+              <input
+                type="checkbox"
+                id="configSyncCalendar"
+                name="configSynced"
+              />
+              <label
+                id="configSyncCalendarLabel"
+                for="configSyncCalendar"
+                data-l10n-id="show-synced-item-calendar"
+              >
+              </label>
+            </div>
+          </li>
+          <li>
+            <div class="config-item">
+              <input
+                type="checkbox"
+                id="configSyncPasswords"
+                name="configSynced"
+              />
+              <label
+                id="configSyncPasswordsLabel"
+                for="configSyncPasswords"
+                data-l10n-id="show-synced-item-passwords"
+              >
+              </label>
+            </div>
+          </li>
+        </ul>
+      </div>
+    </xul:dialog>
+  </body>
+</html>
diff --git a/comm/mail/components/preferences/tagDialog.xhtml b/comm/mail/components/preferences/tagDialog.xhtml
new file mode 100644
index 0000000000..32dd72268d
--- /dev/null
+++ b/comm/mail/components/preferences/tagDialog.xhtml
@@ -0,0 +1,26 @@
+<?xml version="1.0"?>
+
+<!-- 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/. -->
+
+<?xml-stylesheet href="chrome://global/skin/global.css"?>
+<?xml-stylesheet href="chrome://messenger/skin/input-fields.css" type="text/css"?>
+
+<!DOCTYPE window>
+
+<window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        xmlns:html="http://www.w3.org/1999/xhtml"
+        data-l10n-id="tag-dialog-window"
+        style="min-width: 25em;"
+        onload="onLoad();">
+<dialog>
+
+  <stringbundle id="bundle_messenger" src="chrome://messenger/locale/messenger.properties"/>
+
+  <script src="chrome://messenger/content/globalOverlay.js"/>
+  <script src="chrome://global/content/editMenuOverlay.js"/>
+  <script src="chrome://messenger/content/newTagDialog.js"/>
+#include ../../base/content/tagDialog.inc.xhtml
+</dialog>
+</window>
diff --git a/comm/mail/components/preferences/test/browser/browser.ini b/comm/mail/components/preferences/test/browser/browser.ini
new file mode 100644
index 0000000000..44b7d97a31
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/browser.ini
@@ -0,0 +1,20 @@
+[DEFAULT]
+head = head.js
+prefs =
+  mail.provider.suppress_dialog_on_startup=true
+  mail.spotlight.firstRunDone=true
+  mail.winsearch.firstRunDone=true
+  mailnews.start_page.override_url=about:blank
+  mailnews.start_page.url=about:blank
+subsuite = thunderbird
+
+[browser_chat.js]
+[browser_cloudfile.js]
+support-files = files/icon.svg files/management.html
+[browser_compose.js]
+[browser_general.js]
+[browser_openPreferences.js]
+[browser_privacy.js]
+[browser_sync.js]
+skip-if = !nightly_build
+support-files = files/avatar.png
diff --git a/comm/mail/components/preferences/test/browser/browser_chat.js b/comm/mail/components/preferences/test/browser/browser_chat.js
new file mode 100644
index 0000000000..009f2a9211
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/browser_chat.js
@@ -0,0 +1,74 @@
+/* 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/. */
+
+add_task(async () => {
+  await testCheckboxes(
+    "paneChat",
+    "chatPaneCategory",
+    {
+      checkboxID: "reportIdle",
+      pref: "messenger.status.reportIdle",
+      enabledElements: ["#autoAway", "#timeBeforeAway"],
+    },
+    {
+      checkboxID: "sendTyping",
+      pref: "purple.conversations.im.send_typing",
+    },
+    {
+      checkboxID: "desktopChatNotifications",
+      pref: "mail.chat.show_desktop_notifications",
+    },
+    {
+      checkboxID: "getAttention",
+      pref: "messenger.options.getAttentionOnNewMessages",
+    },
+    {
+      checkboxID: "chatNotification",
+      pref: "mail.chat.play_sound",
+      enabledElements: ["#chatSoundType radio"],
+    }
+  );
+
+  Services.prefs.setBoolPref("messenger.status.reportIdle", true);
+  await testCheckboxes("paneChat", "chatPaneCategory", {
+    checkboxID: "autoAway",
+    pref: "messenger.status.awayWhenIdle",
+    enabledElements: ["#defaultIdleAwayMessage"],
+  });
+
+  Services.prefs.setBoolPref("mail.chat.play_sound", true);
+  await testRadioButtons("paneChat", "chatPaneCategory", {
+    pref: "mail.chat.play_sound.type",
+    states: [
+      {
+        id: "chatSoundSystemSound",
+        prefValue: 0,
+      },
+      {
+        id: "chatSoundCustom",
+        prefValue: 1,
+        enabledElements: ["#chatSoundUrlLocation", "#browseForChatSound"],
+      },
+    ],
+  });
+});
+
+add_task(async function testMessageStylePreview() {
+  await openNewPrefsTab("paneChat", "chatPaneCategory");
+  const conversationLoad = TestUtils.topicObserved("conversation-loaded");
+  const [subject] = await conversationLoad;
+  do {
+    await BrowserTestUtils.waitForEvent(subject, "MessagesDisplayed");
+  } while (subject.getPendingMessagesCount() > 0);
+  const messageParent = subject.contentChatNode;
+  let message = messageParent.firstElementChild;
+  const messages = new Set();
+  while (message) {
+    ok(message._originalMsg);
+    messages.add(message._originalMsg);
+    message = message.nextElementSibling;
+  }
+  is(messages.size, 3, "All 3 messages displayed");
+  await closePrefsTab();
+});
diff --git a/comm/mail/components/preferences/test/browser/browser_cloudfile.js b/comm/mail/components/preferences/test/browser/browser_cloudfile.js
new file mode 100644
index 0000000000..9f395f9ab8
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/browser_cloudfile.js
@@ -0,0 +1,796 @@
+/* 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/. */
+
+/* eslint-env webextensions */
+
+let { cloudFileAccounts } = ChromeUtils.import(
+  "resource:///modules/cloudFileAccounts.jsm"
+);
+let { MockRegistrar } = ChromeUtils.importESModule(
+  "resource://testing-common/MockRegistrar.sys.mjs"
+);
+
+function ManagementScript() {
+  browser.test.onMessage.addListener((message, assertMessage, browserStyle) => {
+    if (message !== "check-style") {
+      return;
+    }
+    function verifyButton(buttonElement, expected) {
+      let buttonStyle = window.getComputedStyle(buttonElement);
+      let buttonBackgroundColor = buttonStyle.backgroundColor;
+      if (browserStyle && expected.hasBrowserStyleClass) {
+        browser.test.assertEq(
+          "rgb(9, 150, 248)",
+          buttonBackgroundColor,
+          assertMessage
+        );
+      } else {
+        browser.test.assertTrue(
+          buttonBackgroundColor !== "rgb(9, 150, 248)",
+          assertMessage
+        );
+      }
+    }
+
+    function verifyCheckboxOrRadio(element, expected) {
+      let style = window.getComputedStyle(element);
+      let styledBackground = element.checked
+        ? "rgb(9, 150, 248)"
+        : "rgb(255, 255, 255)";
+      if (browserStyle && expected.hasBrowserStyleClass) {
+        browser.test.assertEq(
+          styledBackground,
+          style.backgroundColor,
+          assertMessage
+        );
+      } else {
+        browser.test.assertTrue(
+          style.backgroundColor != styledBackground,
+          assertMessage
+        );
+      }
+    }
+
+    let normalButton = document.getElementById("normalButton");
+    let browserStyleButton = document.getElementById("browserStyleButton");
+    verifyButton(normalButton, { hasBrowserStyleClass: false });
+    verifyButton(browserStyleButton, { hasBrowserStyleClass: true });
+
+    let normalCheckbox1 = document.getElementById("normalCheckbox1");
+    let normalCheckbox2 = document.getElementById("normalCheckbox2");
+    let browserStyleCheckbox = document.getElementById("browserStyleCheckbox");
+    verifyCheckboxOrRadio(normalCheckbox1, { hasBrowserStyleClass: false });
+    verifyCheckboxOrRadio(normalCheckbox2, { hasBrowserStyleClass: false });
+    verifyCheckboxOrRadio(browserStyleCheckbox, {
+      hasBrowserStyleClass: true,
+    });
+
+    let normalRadio1 = document.getElementById("normalRadio1");
+    let normalRadio2 = document.getElementById("normalRadio2");
+    let browserStyleRadio = document.getElementById("browserStyleRadio");
+    verifyCheckboxOrRadio(normalRadio1, { hasBrowserStyleClass: false });
+    verifyCheckboxOrRadio(normalRadio2, { hasBrowserStyleClass: false });
+    verifyCheckboxOrRadio(browserStyleRadio, { hasBrowserStyleClass: true });
+
+    browser.test.notifyPass("management-ui-browser_style");
+  });
+  browser.test.sendMessage("management-ui-ready");
+}
+
+let extension;
+async function startExtension(browser_style) {
+  let cloud_file = {
+    name: "Mochitest",
+    management_url: "management.html",
+  };
+
+  switch (browser_style) {
+    case "true":
+      cloud_file.browser_style = true;
+      break;
+    case "false":
+      cloud_file.browser_style = false;
+      break;
+  }
+
+  extension = ExtensionTestUtils.loadExtension({
+    async background() {
+      browser.test.onMessage.addListener(async message => {
+        if (message != "set-configured") {
+          return;
+        }
+        let accounts = await browser.cloudFile.getAllAccounts();
+        for (let account of accounts) {
+          await browser.cloudFile.updateAccount(account.id, {
+            configured: true,
+          });
+        }
+        browser.test.sendMessage("ready");
+      });
+    },
+    files: {
+      "management.html": `<html>
+        <body>
+          <a id="a" href="https://www.example.com/">Click me!</a>
+          <button id="normalButton" name="button" class="default">Default</button>
+          <button id="browserStyleButton" name="button" class="browser-style default">Default</button>
+
+          <input id="normalCheckbox1" type="checkbox"/>
+          <input id="normalCheckbox2" type="checkbox"/><label>Checkbox</label>
+          <div class="browser-style">
+            <input id="browserStyleCheckbox" type="checkbox"><label for="browserStyleCheckbox">Checkbox</label>
+          </div>
+
+          <input id="normalRadio1" type="radio"/>
+          <input id="normalRadio2" type="radio"/><label>Radio</label>
+          <div class="browser-style">
+            <input id="browserStyleRadio" checked="" type="radio"><label for="browserStyleRadio">Radio</label>
+          </div>
+        </body>
+        <script src="management.js" type="text/javascript"></script>
+      </html>`,
+      "management.js": ManagementScript,
+    },
+    manifest: {
+      cloud_file,
+      applications: { gecko: { id: "cloudfile@mochitest" } },
+    },
+  });
+
+  info("Starting extension");
+  await extension.startup();
+
+  if (accountIsConfigured) {
+    extension.sendMessage("set-configured");
+    await extension.awaitMessage("ready");
+  }
+}
+
+add_task(async () => {
+  // Register a fake provider representing a built-in provider. We don't
+  // currently ship any built-in providers, but if we did, we should check
+  // if they are present before doing this. Built-in providers can be
+  // problematic for artifact builds.
+  cloudFileAccounts.registerProvider("Fake-Test", {
+    displayName: "XYZ Fake",
+    type: "ext-fake@extensions.thunderbird.net",
+  });
+  registerCleanupFunction(() => {
+    cloudFileAccounts.unregisterProvider("Fake-Test");
+  });
+});
+
+let accountIsConfigured = false;
+
+// Mock the prompt service. We're going to be asked if we're sure
+// we want to remove an account, so let's say yes.
+
+/** @implements {nsIPromptService} */
+let mockPromptService = {
+  confirmCount: 0,
+  confirm() {
+    this.confirmCount++;
+    return true;
+  },
+  QueryInterface: ChromeUtils.generateQI(["nsIPromptService"]),
+};
+/** @implements {nsIExternalProtocolService} */
+let mockExternalProtocolService = {
+  _loadedURLs: [],
+  externalProtocolHandlerExists(aProtocolScheme) {},
+  getApplicationDescription(aScheme) {},
+  getProtocolHandlerInfo(aProtocolScheme) {},
+  getProtocolHandlerInfoFromOS(aProtocolScheme, aFound) {},
+  isExposedProtocol(aProtocolScheme) {},
+  loadURI(aURI, aWindowContext) {
+    this._loadedURLs.push(aURI.spec);
+  },
+  setProtocolHandlerDefaults(aHandlerInfo, aOSHandlerExists) {},
+  urlLoaded(aURL) {
+    return this._loadedURLs.includes(aURL);
+  },
+  QueryInterface: ChromeUtils.generateQI(["nsIExternalProtocolService"]),
+};
+
+let originalPromptService = Services.prompt;
+Services.prompt = mockPromptService;
+
+let mockExternalProtocolServiceCID = MockRegistrar.register(
+  "@mozilla.org/uriloader/external-protocol-service;1",
+  mockExternalProtocolService
+);
+
+registerCleanupFunction(() => {
+  Services.prompt = originalPromptService;
+  MockRegistrar.unregister(mockExternalProtocolServiceCID);
+});
+
+add_task(async function addRemoveAccounts() {
+  is(cloudFileAccounts.providers.length, 1);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  // Load the preferences tab.
+
+  let { prefsDocument, prefsWindow } = await openNewPrefsTab(
+    "paneCompose",
+    "compositionAttachmentsCategory"
+  );
+
+  // Check everything is as it should be.
+
+  let accountList = prefsDocument.getElementById("cloudFileView");
+  is(accountList.itemCount, 0);
+
+  let buttonList = prefsDocument.getElementById("addCloudFileAccountButtons");
+  ok(!buttonList.hidden);
+  is(buttonList.childElementCount, 1);
+  is(
+    buttonList.children[0].getAttribute("value"),
+    "ext-fake@extensions.thunderbird.net"
+  );
+
+  let menuButton = prefsDocument.getElementById("addCloudFileAccount");
+  ok(menuButton.hidden);
+  is(menuButton.itemCount, 1);
+  is(
+    menuButton.getItemAtIndex(0).getAttribute("value"),
+    "ext-fake@extensions.thunderbird.net"
+  );
+
+  let removeButton = prefsDocument.getElementById("removeCloudFileAccount");
+  ok(removeButton.disabled);
+
+  let cloudFileDefaultPanel = prefsDocument.getElementById(
+    "cloudFileDefaultPanel"
+  );
+  ok(!cloudFileDefaultPanel.hidden);
+
+  let browserWrapper = prefsDocument.getElementById("cloudFileSettingsWrapper");
+  is(browserWrapper.childElementCount, 0);
+
+  // Register our test provider.
+
+  await startExtension();
+  is(cloudFileAccounts.providers.length, 2);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  await new Promise(resolve => prefsWindow.requestAnimationFrame(resolve));
+
+  is(buttonList.childElementCount, 2);
+  is(
+    buttonList.children[0].getAttribute("value"),
+    "ext-fake@extensions.thunderbird.net"
+  );
+  is(buttonList.children[1].getAttribute("value"), "ext-cloudfile@mochitest");
+  is(
+    buttonList.children[1].style.listStyleImage,
+    `url("chrome://messenger/content/extension.svg")`
+  );
+
+  is(menuButton.itemCount, 2);
+  is(
+    menuButton.getItemAtIndex(0).getAttribute("value"),
+    "ext-fake@extensions.thunderbird.net"
+  );
+  is(
+    menuButton.getItemAtIndex(1).getAttribute("value"),
+    "ext-cloudfile@mochitest"
+  );
+  is(
+    menuButton.getItemAtIndex(1).getAttribute("image"),
+    "chrome://messenger/content/extension.svg"
+  );
+
+  // Create a new account.
+
+  EventUtils.synthesizeMouseAtCenter(
+    buttonList.children[1],
+    { clickCount: 1 },
+    prefsWindow
+  );
+  is(cloudFileAccounts.accounts.length, 1);
+  is(cloudFileAccounts.configuredAccounts.length, 0);
+
+  let account = cloudFileAccounts.accounts[0];
+  let accountKey = account.accountKey;
+  is(cloudFileAccounts.accounts[0].type, "ext-cloudfile@mochitest");
+
+  // Check prefs were updated.
+
+  is(
+    Services.prefs.getCharPref(
+      `mail.cloud_files.accounts.${accountKey}.displayName`
+    ),
+    "Mochitest"
+  );
+  is(
+    Services.prefs.getCharPref(`mail.cloud_files.accounts.${accountKey}.type`),
+    "ext-cloudfile@mochitest"
+  );
+
+  // Check UI was updated.
+
+  is(accountList.itemCount, 1);
+  is(accountList.selectedIndex, 0);
+  ok(!removeButton.disabled);
+
+  let accountListItem = accountList.selectedItem;
+  is(accountListItem.getAttribute("value"), accountKey);
+  is(
+    accountListItem.querySelector(".typeIcon:not(.configuredWarning)").src,
+    "chrome://messenger/content/extension.svg"
+  );
+  is(accountListItem.querySelector("label").value, "Mochitest");
+  is(accountListItem.querySelector(".configuredWarning").hidden, false);
+
+  ok(cloudFileDefaultPanel.hidden);
+  is(browserWrapper.childElementCount, 1);
+
+  let browser = browserWrapper.firstElementChild;
+  if (
+    browser.webProgress?.isLoadingDocument ||
+    browser.currentURI?.spec == "about:blank"
+  ) {
+    await BrowserTestUtils.browserLoaded(browser);
+  }
+  is(
+    browser.currentURI.pathQueryRef,
+    `/management.html?accountId=${accountKey}`
+  );
+  await extension.awaitMessage("management-ui-ready");
+
+  let tabmail = document.getElementById("tabmail");
+  let tabCount = tabmail.tabInfo.length;
+  BrowserTestUtils.synthesizeMouseAtCenter("a", {}, browser);
+  // It might take a moment to get to the external protocol service.
+  // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+  await new Promise(resolve => setTimeout(resolve, 500));
+  ok(
+    mockExternalProtocolService.urlLoaded("https://www.example.com/"),
+    "Link click sent to external protocol service."
+  );
+  is(tabmail.tabInfo.length, tabCount, "No new tab opened");
+
+  // Rename the account.
+
+  EventUtils.synthesizeMouseAtCenter(
+    accountListItem,
+    { clickCount: 1 },
+    prefsWindow
+  );
+
+  await new Promise(resolve => prefsWindow.requestAnimationFrame(resolve));
+
+  is(
+    prefsDocument.activeElement.closest("input"),
+    accountListItem.querySelector("input")
+  );
+  ok(accountListItem.querySelector("label").hidden);
+  ok(!accountListItem.querySelector("input").hidden);
+  is(accountListItem.querySelector("input").value, "Mochitest");
+  EventUtils.synthesizeKey("VK_RIGHT", undefined, prefsWindow);
+  EventUtils.synthesizeKey("!", undefined, prefsWindow);
+  EventUtils.synthesizeKey("VK_RETURN", undefined, prefsWindow);
+
+  await new Promise(resolve => prefsWindow.requestAnimationFrame(resolve));
+
+  is(prefsDocument.activeElement, accountList);
+  ok(!accountListItem.querySelector("label").hidden);
+  is(accountListItem.querySelector("label").value, "Mochitest!");
+  ok(accountListItem.querySelector("input").hidden);
+  is(
+    Services.prefs.getCharPref(
+      `mail.cloud_files.accounts.${accountKey}.displayName`
+    ),
+    "Mochitest!"
+  );
+
+  // Start to rename the account, but bail out.
+
+  EventUtils.synthesizeMouseAtCenter(
+    accountListItem,
+    { clickCount: 1 },
+    prefsWindow
+  );
+
+  await new Promise(resolve => prefsWindow.requestAnimationFrame(resolve));
+
+  is(
+    prefsDocument.activeElement.closest("input"),
+    accountListItem.querySelector("input")
+  );
+  EventUtils.synthesizeKey("O", undefined, prefsWindow);
+  EventUtils.synthesizeKey("o", undefined, prefsWindow);
+  EventUtils.synthesizeKey("p", undefined, prefsWindow);
+  EventUtils.synthesizeKey("s", undefined, prefsWindow);
+  EventUtils.synthesizeKey("VK_ESCAPE", undefined, prefsWindow);
+
+  await new Promise(resolve => prefsWindow.requestAnimationFrame(resolve));
+
+  is(prefsDocument.activeElement, accountList);
+  ok(!accountListItem.querySelector("label").hidden);
+  is(accountListItem.querySelector("label").value, "Mochitest!");
+  ok(accountListItem.querySelector("input").hidden);
+  is(
+    Services.prefs.getCharPref(
+      `mail.cloud_files.accounts.${accountKey}.displayName`
+    ),
+    "Mochitest!"
+  );
+
+  // Configure the account.
+
+  account.configured = true;
+  accountIsConfigured = true;
+  cloudFileAccounts.emit("accountConfigured", account);
+
+  await new Promise(resolve => prefsWindow.requestAnimationFrame(resolve));
+
+  is(accountListItem.querySelector(".configuredWarning").hidden, true);
+  is(cloudFileAccounts.accounts.length, 1);
+  is(cloudFileAccounts.configuredAccounts.length, 1);
+
+  // Remove the test provider. The list item, button, and browser should disappear.
+
+  info("Stopping extension");
+  await extension.unload();
+  is(cloudFileAccounts.providers.length, 1);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  await new Promise(resolve => prefsWindow.requestAnimationFrame(resolve));
+
+  is(buttonList.childElementCount, 1);
+  is(
+    buttonList.children[0].getAttribute("value"),
+    "ext-fake@extensions.thunderbird.net"
+  );
+  is(menuButton.itemCount, 1);
+  is(
+    menuButton.getItemAtIndex(0).getAttribute("value"),
+    "ext-fake@extensions.thunderbird.net"
+  );
+  is(accountList.itemCount, 0);
+  ok(!cloudFileDefaultPanel.hidden);
+  is(browserWrapper.childElementCount, 0);
+
+  // Re-add the test provider.
+
+  await startExtension();
+
+  is(cloudFileAccounts.providers.length, 2);
+  is(cloudFileAccounts.accounts.length, 1);
+  is(cloudFileAccounts.configuredAccounts.length, 1);
+
+  await new Promise(resolve => prefsWindow.requestAnimationFrame(resolve));
+
+  is(buttonList.childElementCount, 2);
+  is(
+    buttonList.children[0].getAttribute("value"),
+    "ext-fake@extensions.thunderbird.net"
+  );
+  is(buttonList.children[1].getAttribute("value"), "ext-cloudfile@mochitest");
+
+  is(menuButton.itemCount, 2);
+  is(
+    menuButton.getItemAtIndex(0).getAttribute("value"),
+    "ext-fake@extensions.thunderbird.net"
+  );
+  is(
+    menuButton.getItemAtIndex(1).getAttribute("value"),
+    "ext-cloudfile@mochitest"
+  );
+
+  is(accountList.itemCount, 1);
+  is(accountList.selectedIndex, -1);
+  ok(removeButton.disabled);
+
+  accountListItem = accountList.getItemAtIndex(0);
+  is(
+    Services.prefs.getCharPref(
+      `mail.cloud_files.accounts.${accountKey}.displayName`
+    ),
+    "Mochitest!"
+  );
+
+  EventUtils.synthesizeMouseAtCenter(
+    accountList.getItemAtIndex(0),
+    { clickCount: 1 },
+    prefsWindow
+  );
+  ok(!removeButton.disabled);
+  EventUtils.synthesizeMouseAtCenter(
+    removeButton,
+    { clickCount: 1 },
+    prefsWindow
+  );
+  is(mockPromptService.confirmCount, 1);
+
+  ok(
+    !Services.prefs.prefHasUserValue(
+      `mail.cloud_files.accounts.${accountKey}.displayName`
+    )
+  );
+  ok(
+    !Services.prefs.prefHasUserValue(
+      `mail.cloud_files.accounts.${accountKey}.type`
+    )
+  );
+
+  is(cloudFileAccounts.providers.length, 2);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  info("Stopping extension");
+  await extension.unload();
+  is(cloudFileAccounts.providers.length, 1);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  // Close the preferences tab.
+
+  await closePrefsTab();
+});
+
+async function subtestBrowserStyle(assertMessage, expected) {
+  is(cloudFileAccounts.providers.length, 1);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  // Load the preferences tab.
+
+  let { prefsDocument, prefsWindow } = await openNewPrefsTab(
+    "paneCompose",
+    "compositionAttachmentsCategory"
+  );
+
+  // Minimal check everything is as it should be.
+
+  let accountList = prefsDocument.getElementById("cloudFileView");
+  is(accountList.itemCount, 0);
+
+  let buttonList = prefsDocument.getElementById("addCloudFileAccountButtons");
+  ok(!buttonList.hidden);
+
+  let browserWrapper = prefsDocument.getElementById("cloudFileSettingsWrapper");
+  is(browserWrapper.childElementCount, 0);
+
+  // Register our test provider.
+
+  await startExtension(expected.browser_style);
+  is(cloudFileAccounts.providers.length, 2);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  await new Promise(resolve => prefsWindow.requestAnimationFrame(resolve));
+
+  is(buttonList.childElementCount, 2);
+  is(buttonList.children[1].getAttribute("value"), "ext-cloudfile@mochitest");
+
+  // Create a new account.
+
+  EventUtils.synthesizeMouseAtCenter(
+    buttonList.children[1],
+    { clickCount: 1 },
+    prefsWindow
+  );
+  is(cloudFileAccounts.accounts.length, 1);
+  is(cloudFileAccounts.configuredAccounts.length, 0);
+
+  let account = cloudFileAccounts.accounts[0];
+  let accountKey = account.accountKey;
+  is(cloudFileAccounts.accounts[0].type, "ext-cloudfile@mochitest");
+
+  // Minimal check UI was updated.
+
+  is(accountList.itemCount, 1);
+  is(accountList.selectedIndex, 0);
+
+  let accountListItem = accountList.selectedItem;
+  is(accountListItem.getAttribute("value"), accountKey);
+
+  is(browserWrapper.childElementCount, 1);
+  let browser = browserWrapper.firstElementChild;
+  if (
+    browser.webProgress?.isLoadingDocument ||
+    browser.currentURI?.spec == "about:blank"
+  ) {
+    await BrowserTestUtils.browserLoaded(browser);
+  }
+  is(
+    browser.currentURI.pathQueryRef,
+    `/management.html?accountId=${accountKey}`
+  );
+  await extension.awaitMessage("management-ui-ready");
+
+  // Test browser_style
+
+  extension.sendMessage(
+    "check-style",
+    assertMessage,
+    expected.browser_style == "true"
+  );
+  await extension.awaitFinish("management-ui-browser_style");
+
+  // Remove the account
+
+  accountListItem = accountList.getItemAtIndex(0);
+  EventUtils.synthesizeMouseAtCenter(
+    accountList.getItemAtIndex(0),
+    { clickCount: 1 },
+    prefsWindow
+  );
+
+  let removeButton = prefsDocument.getElementById("removeCloudFileAccount");
+  ok(!removeButton.disabled);
+  EventUtils.synthesizeMouseAtCenter(
+    removeButton,
+    { clickCount: 1 },
+    prefsWindow
+  );
+  is(mockPromptService.confirmCount, expected.confirmCount);
+
+  is(cloudFileAccounts.providers.length, 2);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  info("Stopping extension");
+  await extension.unload();
+  is(cloudFileAccounts.providers.length, 1);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  // Close the preferences tab.
+
+  await closePrefsTab();
+}
+
+add_task(async function test_without_setting_browser_style() {
+  await subtestBrowserStyle(
+    "Expected correct style when browser_style is excluded",
+    {
+      confirmCount: 2,
+      browser_style: "default",
+    }
+  );
+});
+
+add_task(async function test_with_browser_style_set_to_true() {
+  await subtestBrowserStyle(
+    "Expected correct style when browser_style is set to `true`",
+    {
+      confirmCount: 3,
+      browser_style: "true",
+    }
+  );
+});
+
+add_task(async function test_with_browser_style_set_to_false() {
+  await subtestBrowserStyle(
+    "Expected no style when browser_style is set to `false`",
+    {
+      confirmCount: 4,
+      browser_style: "false",
+    }
+  );
+});
+
+add_task(async function accountListOverflow() {
+  is(cloudFileAccounts.providers.length, 1);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  // Register our test provider.
+
+  await startExtension();
+
+  is(cloudFileAccounts.providers.length, 2);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  // Load the preferences tab.
+
+  let { prefsDocument, prefsWindow } = await openNewPrefsTab(
+    "paneCompose",
+    "compositionAttachmentsCategory"
+  );
+
+  let accountList = prefsDocument.getElementById("cloudFileView");
+  is(accountList.itemCount, 0);
+
+  let buttonList = prefsDocument.getElementById("addCloudFileAccountButtons");
+  ok(!buttonList.hidden);
+  is(buttonList.childElementCount, 2);
+  is(buttonList.children[0].getAttribute("value"), "ext-cloudfile@mochitest");
+
+  let menuButton = prefsDocument.getElementById("addCloudFileAccount");
+  ok(menuButton.hidden);
+
+  // Add new accounts until the list overflows. The list of buttons should be hidden
+  // and the button with the drop-down should appear.
+
+  let count = 0;
+  do {
+    let readyPromise = extension.awaitMessage("management-ui-ready");
+    EventUtils.synthesizeMouseAtCenter(
+      buttonList.children[0],
+      { clickCount: 1 },
+      prefsWindow
+    );
+    await readyPromise;
+    // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+    await new Promise(r => setTimeout(r, 500));
+    if (buttonList.hidden) {
+      break;
+    }
+  } while (++count < 25);
+
+  ok(count < 24); // If count reaches 25, we have a problem.
+  ok(!menuButton.hidden);
+
+  // Remove the added accounts. The list of buttons should not reappear and the
+  // button with the drop-down should remain.
+
+  let removeButton = prefsDocument.getElementById("removeCloudFileAccount");
+  do {
+    EventUtils.synthesizeMouseAtCenter(
+      accountList.getItemAtIndex(0),
+      { clickCount: 1 },
+      prefsWindow
+    );
+    EventUtils.synthesizeMouseAtCenter(
+      removeButton,
+      { clickCount: 1 },
+      prefsWindow
+    );
+    await new Promise(resolve => setTimeout(resolve));
+  } while (--count > 0);
+
+  ok(buttonList.hidden);
+  ok(!menuButton.hidden);
+
+  // Close the preferences tab.
+
+  await closePrefsTab();
+  info("Stopping extension");
+  await extension.unload();
+  Services.prefs.deleteBranch("mail.cloud_files.accounts");
+});
+
+add_task(async function accountListOrder() {
+  is(cloudFileAccounts.providers.length, 1);
+  is(cloudFileAccounts.accounts.length, 0);
+
+  for (let [key, displayName] of [
+    ["someKey1", "carl's Account"],
+    ["someKey2", "Amber's Account"],
+    ["someKey3", "alice's Account"],
+    ["someKey4", "Bob's Account"],
+  ]) {
+    Services.prefs.setCharPref(
+      `mail.cloud_files.accounts.${key}.type`,
+      "ext-cloudfile@mochitest"
+    );
+    Services.prefs.setCharPref(
+      `mail.cloud_files.accounts.${key}.displayName`,
+      displayName
+    );
+  }
+
+  // Register our test provider.
+
+  await startExtension();
+
+  is(cloudFileAccounts.providers.length, 2);
+  is(cloudFileAccounts.accounts.length, 4);
+
+  let { prefsDocument } = await openNewPrefsTab(
+    "paneCompose",
+    "compositionAttachmentsCategory"
+  );
+
+  let accountList = prefsDocument.getElementById("cloudFileView");
+  is(accountList.itemCount, 4);
+
+  is(accountList.getItemAtIndex(0).value, "someKey3");
+  is(accountList.getItemAtIndex(1).value, "someKey2");
+  is(accountList.getItemAtIndex(2).value, "someKey4");
+  is(accountList.getItemAtIndex(3).value, "someKey1");
+
+  await closePrefsTab();
+  info("Stopping extension");
+  await extension.unload();
+  Services.prefs.deleteBranch("mail.cloud_files.accounts");
+});
diff --git a/comm/mail/components/preferences/test/browser/browser_compose.js b/comm/mail/components/preferences/test/browser/browser_compose.js
new file mode 100644
index 0000000000..ea253cb555
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/browser_compose.js
@@ -0,0 +1,87 @@
+/* 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/. */
+
+add_task(async () => {
+  await testCheckboxes(
+    "paneCompose",
+    "compositionMainCategory",
+    {
+      checkboxID: "addExtension",
+      pref: "mail.forward_add_extension",
+    },
+    {
+      checkboxID: "autoSave",
+      pref: "mail.compose.autosave",
+      enabledElements: ["#autoSaveInterval"],
+    },
+    {
+      checkboxID: "mailWarnOnSendAccelKey",
+      pref: "mail.warn_on_send_accel_key",
+    },
+    {
+      checkboxID: "spellCheckBeforeSend",
+      pref: "mail.SpellCheckBeforeSend",
+    },
+    {
+      checkboxID: "inlineSpellCheck",
+      pref: "mail.spellcheck.inline",
+    }
+  );
+
+  await testCheckboxes(
+    "paneCompose",
+    "FontSelect",
+    {
+      checkboxID: "useReaderDefaults",
+      pref: "msgcompose.default_colors",
+      enabledInverted: true,
+      enabledElements: [
+        "#textColorLabel",
+        "#textColorButton",
+        "#backgroundColorLabel",
+        "#backgroundColorButton",
+      ],
+    },
+    {
+      checkboxID: "defaultToParagraph",
+      pref: "mail.compose.default_to_paragraph",
+    }
+  );
+
+  await testCheckboxes(
+    "paneCompose",
+    "compositionAddressingCategory",
+    {
+      checkboxID: "addressingAutocomplete",
+      pref: "mail.enable_autocomplete",
+    },
+    {
+      checkboxID: "autocompleteLDAP",
+      pref: "ldap_2.autoComplete.useDirectory",
+      enabledElements: ["#directoriesList", "#editButton"],
+    },
+    {
+      checkboxID: "emailCollectionOutgoing",
+      pref: "mail.collect_email_address_outgoing",
+      enabledElements: ["#localDirectoriesList"],
+    }
+  );
+});
+
+add_task(async () => {
+  await testCheckboxes(
+    "paneCompose",
+    "compositionAttachmentsCategory",
+    {
+      checkboxID: "attachment_reminder_label",
+      pref: "mail.compose.attachment_reminder",
+      enabledElements: ["#attachment_reminder_button"],
+    },
+    {
+      checkboxID: "enableThreshold",
+      pref: "mail.compose.big_attachments.notify",
+      enabledElements: ["#cloudFileThreshold"],
+    }
+  );
+});
diff --git a/comm/mail/components/preferences/test/browser/browser_general.js b/comm/mail/components/preferences/test/browser/browser_general.js
new file mode 100644
index 0000000000..f011be1e38
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/browser_general.js
@@ -0,0 +1,380 @@
+/* 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/. */
+
+var { MailServices } = ChromeUtils.import(
+  "resource:///modules/MailServices.jsm"
+);
+
+add_task(async () => {
+  requestLongerTimeout(2);
+
+  // Temporarily disable `Once` StaticPrefs check for this test so that we
+  // can change layers.acceleration.disabled without debug builds failing.
+  await SpecialPowers.pushPrefEnv({
+    set: [["preferences.force-disable.check.once.policy", true]],
+  });
+});
+
+add_task(async () => {
+  await testCheckboxes(
+    "paneGeneral",
+    "generalCategory",
+    {
+      checkboxID: "mailnewsStartPageEnabled",
+      pref: "mailnews.start_page.enabled",
+      enabledElements: [
+        "#mailnewsStartPageUrl",
+        "#mailnewsStartPageUrl + button",
+      ],
+    },
+    {
+      checkboxID: "alwaysCheckDefault",
+      pref: "mail.shell.checkDefaultClient",
+    }
+  );
+});
+
+add_task(async () => {
+  await testCheckboxes(
+    "paneGeneral",
+    "scrollingGroup",
+    {
+      checkboxID: "useAutoScroll",
+      pref: "general.autoScroll",
+    },
+    {
+      checkboxID: "useSmoothScrolling",
+      pref: "general.smoothScroll",
+    }
+  );
+});
+
+add_task(async () => {
+  await testCheckboxes(
+    "paneGeneral",
+    "enableGloda",
+    {
+      checkboxID: "enableGloda",
+      pref: "mailnews.database.global.indexer.enabled",
+    },
+    {
+      checkboxID: "allowHWAccel",
+      pref: "layers.acceleration.disabled",
+      prefValues: [true, false],
+    }
+  );
+});
+
+add_task(async () => {
+  if (AppConstants.platform != "macosx") {
+    await testCheckboxes(
+      "paneGeneral",
+      "incomingMailCategory",
+      {
+        checkboxID: "newMailNotification",
+        pref: "mail.biff.play_sound",
+        enabledElements: ["#soundType radio"],
+      },
+      {
+        checkboxID: "newMailNotificationAlert",
+        pref: "mail.biff.show_alert",
+        enabledElements: ["#customizeMailAlert"],
+      }
+    );
+  }
+});
+
+add_task(async () => {
+  if (AppConstants.platform == "macosx") {
+    return;
+  }
+
+  Services.prefs.setBoolPref("mail.biff.play_sound", true);
+
+  await testRadioButtons("paneGeneral", "incomingMailCategory", {
+    pref: "mail.biff.play_sound.type",
+    states: [
+      {
+        id: "system",
+        prefValue: 0,
+      },
+      {
+        id: "custom",
+        prefValue: 1,
+        enabledElements: ["#soundUrlLocation", "#browseForSound"],
+      },
+    ],
+  });
+});
+
+add_task(async () => {
+  await testCheckboxes("paneGeneral", "fontsGroup", {
+    checkboxID: "displayGlyph",
+    pref: "mail.display_glyph",
+  });
+
+  await testCheckboxes(
+    "paneGeneral",
+    "readingAndDisplayCategory",
+    {
+      checkboxID: "automaticallyMarkAsRead",
+      pref: "mailnews.mark_message_read.auto",
+      enabledElements: ["#markAsReadAutoPreferences radio"],
+    },
+    {
+      checkboxID: "closeMsgOnMoveOrDelete",
+      pref: "mail.close_message_window.on_delete",
+    },
+    {
+      checkboxID: "showCondensedAddresses",
+      pref: "mail.showCondensedAddresses",
+    }
+  );
+});
+
+add_task(async () => {
+  Services.prefs.setBoolPref("mailnews.mark_message_read.auto", true);
+
+  await testRadioButtons(
+    "paneGeneral",
+    "mark_read_immediately",
+    {
+      pref: "mailnews.mark_message_read.delay",
+      states: [
+        {
+          id: "mark_read_immediately",
+          prefValue: false,
+        },
+        {
+          id: "markAsReadAfterDelay",
+          prefValue: true,
+          enabledElements: ["#markAsReadDelay"],
+        },
+      ],
+    },
+    {
+      pref: "mail.openMessageBehavior",
+      states: [
+        {
+          id: "newTab",
+          prefValue: 2,
+        },
+        {
+          id: "newWindow",
+          prefValue: 0,
+        },
+        {
+          id: "existingWindow",
+          prefValue: 1,
+        },
+      ],
+    }
+  );
+});
+
+add_task(async () => {
+  // We don't want to wake up the platform search for this test.
+  // if (AppConstants.platform == "macosx") {
+  //   tests.push({
+  //     checkboxID: "searchIntegration",
+  //     pref: "mail.spotlight.enable",
+  //   });
+  // } else if (AppConstants.platform == "win") {
+  //   tests.push({
+  //     checkboxID: "searchIntegration",
+  //     pref: "mail.winsearch.enable",
+  //   });
+  // }
+
+  await testCheckboxes(
+    "paneGeneral",
+    "allowSmartSize",
+    {
+      checkboxID: "allowSmartSize",
+      pref: "browser.cache.disk.smart_size.enabled",
+      prefValues: [true, false],
+      enabledElements: ["#cacheSize"],
+    },
+    {
+      checkboxID: "offlineCompactFolder",
+      pref: "mail.prompt_purge_threshhold",
+      enabledElements: [
+        "#offlineCompactFolderMin",
+        "#offlineCompactFolderAutomatically",
+      ],
+    }
+  );
+});
+
+add_task(async () => {
+  await testRadioButtons("paneGeneral", "formatLocale", {
+    pref: "intl.regional_prefs.use_os_locales",
+    states: [
+      {
+        id: "appLocale",
+        prefValue: false,
+      },
+      {
+        id: "rsLocale",
+        prefValue: true,
+      },
+    ],
+  });
+});
+
+add_task(async () => {
+  await testRadioButtons("paneGeneral", "filesAttachmentCategory", {
+    pref: "browser.download.useDownloadDir",
+    states: [
+      {
+        id: "saveTo",
+        prefValue: true,
+        enabledElements: ["#downloadFolder", "#chooseFolder"],
+      },
+      {
+        id: "alwaysAsk",
+        prefValue: false,
+      },
+    ],
+  });
+});
+
+add_task(async function testTagDialog() {
+  const { prefsDocument, prefsWindow } = await openNewPrefsTab(
+    "paneGeneral",
+    "tagsCategory"
+  );
+
+  let newTagDialogPromise = BrowserTestUtils.promiseAlertDialogOpen(
+    undefined,
+    "chrome://messenger/content/preferences/tagDialog.xhtml",
+    {
+      isSubDialog: true,
+      async callback(dialogWindow) {
+        await TestUtils.waitForCondition(
+          () => Services.focus.focusedWindow == dialogWindow,
+          "waiting for subdialog to be focused"
+        );
+
+        const dialogDocument = dialogWindow.document;
+
+        EventUtils.sendString("tbird", dialogWindow);
+        // "#000080" == rgb(0, 0, 128);
+        dialogDocument.getElementById("tagColorPicker").value = "#000080";
+
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.querySelector("dialog").getButton("accept"),
+          {},
+          dialogWindow
+        );
+        await new Promise(r => setTimeout(r));
+      },
+    }
+  );
+
+  let newTagButton = prefsDocument.getElementById("newTagButton");
+  EventUtils.synthesizeMouseAtCenter(newTagButton, {}, prefsWindow);
+  await newTagDialogPromise;
+
+  let tagList = prefsDocument.getElementById("tagList");
+
+  Assert.ok(
+    tagList.querySelector('richlistitem[value="tbird"]'),
+    "new tbird tag should be in the list"
+  );
+  Assert.equal(
+    tagList.querySelector('richlistitem[value="tbird"]').style.color,
+    "rgb(0, 0, 128)",
+    "tbird tag color should be correct"
+  );
+  Assert.equal(
+    tagList.querySelectorAll('richlistitem[value="tbird"]').length,
+    1,
+    "new tbird tag should be in the list exactly once"
+  );
+
+  Assert.equal(
+    tagList.querySelector('richlistitem[value="tbird"]'),
+    tagList.selectedItem,
+    "tbird tag should be selected"
+  );
+
+  // Now edit the tag. The key should stay the same, name and color will change.
+
+  let editTagDialogPromise = BrowserTestUtils.promiseAlertDialogOpen(
+    undefined,
+    "chrome://messenger/content/preferences/tagDialog.xhtml",
+    {
+      isSubDialog: true,
+      async callback(dialogWindow) {
+        await TestUtils.waitForCondition(
+          () => Services.focus.focusedWindow == dialogWindow,
+          "waiting for subdialog to be focused"
+        );
+
+        const dialogDocument = dialogWindow.document;
+
+        Assert.equal(
+          dialogDocument.getElementById("name").value,
+          "tbird",
+          "should have existing tbird tag name prefilled"
+        );
+        Assert.equal(
+          dialogDocument.getElementById("tagColorPicker").value,
+          "#000080",
+          "should have existing tbird tag color prefilled"
+        );
+
+        EventUtils.sendString("-xx", dialogWindow); // => tbird-xx
+        // "#FFD700" == rgb(255, 215, 0);
+        dialogDocument.getElementById("tagColorPicker").value = "#FFD700";
+
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.querySelector("dialog").getButton("accept"),
+          {},
+          dialogWindow
+        );
+        await new Promise(r => setTimeout(r));
+      },
+    }
+  );
+
+  let editTagButton = prefsDocument.getElementById("editTagButton");
+  EventUtils.synthesizeMouseAtCenter(editTagButton, {}, prefsWindow);
+  await editTagDialogPromise;
+
+  Assert.ok(
+    tagList.querySelector(
+      'richlistitem[value="tbird"] > label[value="tbird-xx"]'
+    ),
+    "tbird-xx tag should be in the list"
+  );
+  Assert.equal(
+    tagList.querySelector('richlistitem[value="tbird"]').style.color,
+    "rgb(255, 215, 0)",
+    "tbird-xx tag color should be correct"
+  );
+  Assert.equal(
+    tagList.querySelectorAll('richlistitem[value="tbird"]').length,
+    1,
+    "tbird-xx tag should be in the list exactly once"
+  );
+
+  // And remove it.
+
+  EventUtils.synthesizeMouseAtCenter(
+    prefsDocument.getElementById("removeTagButton"),
+    {},
+    prefsWindow
+  );
+  await new Promise(r => setTimeout(r));
+
+  Assert.equal(
+    tagList.querySelector('richlistitem[value="tbird"]'),
+    null,
+    "tbird-xx (with key tbird) tag should have been removed from the list"
+  );
+
+  await closePrefsTab();
+});
diff --git a/comm/mail/components/preferences/test/browser/browser_openPreferences.js b/comm/mail/components/preferences/test/browser/browser_openPreferences.js
new file mode 100644
index 0000000000..01aceb085a
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/browser_openPreferences.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/. */
+
+function getStoredLastSelected() {
+  return Services.xulStore.getValue(
+    "about:preferences",
+    "paneDeck",
+    "lastSelected"
+  );
+}
+
+add_task(async () => {
+  // Check that openPreferencesTab with no arguments and no stored value opens the first pane.
+  Services.xulStore.removeDocument("about:preferences");
+
+  let { prefsWindow } = await openNewPrefsTab();
+  is(prefsWindow.gLastCategory.category, "paneGeneral");
+
+  await closePrefsTab();
+});
+
+add_task(async () => {
+  // Check that openPreferencesTab with one argument opens the right pane…
+  Services.xulStore.removeDocument("about:preferences");
+
+  await openNewPrefsTab("panePrivacy");
+  is(getStoredLastSelected(), "panePrivacy");
+
+  await closePrefsTab();
+
+  // … even with a value in the XULStore.
+  await openNewPrefsTab("paneCompose");
+  is(getStoredLastSelected(), "paneCompose");
+
+  await closePrefsTab();
+});
diff --git a/comm/mail/components/preferences/test/browser/browser_privacy.js b/comm/mail/components/preferences/test/browser/browser_privacy.js
new file mode 100644
index 0000000000..1b91ec35e8
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/browser_privacy.js
@@ -0,0 +1,454 @@
+/* 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/. */
+
+add_task(async () => {
+  await testCheckboxes(
+    "panePrivacy",
+    "privacyCategory",
+    {
+      checkboxID: "acceptRemoteContent",
+      pref: "mailnews.message_display.disable_remote_image",
+      prefValues: [true, false],
+    },
+    {
+      checkboxID: "keepHistory",
+      pref: "places.history.enabled",
+    },
+    {
+      checkboxID: "acceptCookies",
+      pref: "network.cookie.cookieBehavior",
+      prefValues: [2, 0],
+      enabledElements: ["#acceptThirdPartyMenu"],
+      unaffectedElements: ["#cookieExceptions"],
+    },
+    {
+      checkboxID: "privacyDoNotTrackCheckbox",
+      pref: "privacy.donottrackheader.enabled",
+    }
+  );
+});
+
+add_task(async () => {
+  await testCheckboxes(
+    "panePrivacy",
+    "privacyJunkCategory",
+    {
+      checkboxID: "manualMark",
+      pref: "mail.spam.manualMark",
+      enabledElements: ["#manualMarkMode radio"],
+    },
+    {
+      checkboxID: "markAsReadOnSpam",
+      pref: "mail.spam.markAsReadOnSpam",
+    },
+    {
+      checkboxID: "enableJunkLogging",
+      pref: "mail.spam.logging.enabled",
+      enabledElements: ["#openJunkLogButton"],
+    }
+  );
+
+  await testCheckboxes("panePrivacy", "privacySecurityCategory", {
+    checkboxID: "enablePhishingDetector",
+    pref: "mail.phishing.detection.enabled",
+  });
+
+  await testCheckboxes("panePrivacy", "enableAntiVirusQuarantine", {
+    checkboxID: "enableAntiVirusQuarantine",
+    pref: "mailnews.downloadToTempFile",
+  });
+});
+
+add_task(async () => {
+  Services.prefs.setBoolPref("mail.spam.manualMark", true);
+
+  await testRadioButtons("panePrivacy", "privacyJunkCategory", {
+    pref: "mail.spam.manualMarkMode",
+    states: [
+      {
+        id: "manualMarkMode0",
+        prefValue: 0,
+      },
+      {
+        id: "manualMarkMode1",
+        prefValue: 1,
+      },
+    ],
+  });
+});
+
+add_task(async () => {
+  // Telemetry pref is locked.
+  // await testCheckboxes("paneAdvanced", undefined, {
+  //   checkboxID: "submitTelemetryBox",
+  //   pref: "toolkit.telemetry.enabled",
+  // });
+
+  await testCheckboxes("panePrivacy", "enableOCSP", {
+    checkboxID: "enableOCSP",
+    pref: "security.OCSP.enabled",
+    prefValues: [0, 1],
+  });
+});
+
+// Here we'd test the update choices, but I don't want to go near that.
+add_task(async () => {
+  await testRadioButtons("panePrivacy", "enableOCSP", {
+    pref: "security.default_personal_cert",
+    states: [
+      {
+        id: "certSelectionAuto",
+        prefValue: "Select Automatically",
+      },
+      {
+        id: "certSelectionAsk",
+        prefValue: "Ask Every Time",
+      },
+    ],
+  });
+});
+
+add_task(async function testRemoteContentDialog() {
+  const { prefsDocument, prefsWindow } = await openNewPrefsTab("panePrivacy");
+
+  let dialogPromise = BrowserTestUtils.promiseAlertDialogOpen(
+    undefined,
+    "chrome://messenger/content/preferences/permissions.xhtml",
+    {
+      isSubDialog: true,
+      async callback(dialogWindow) {
+        await TestUtils.waitForCondition(
+          () => Services.focus.focusedWindow == dialogWindow,
+          "waiting for subdialog to be focused"
+        );
+
+        const dialogDocument = dialogWindow.document;
+        const url = dialogDocument.getElementById("url");
+        const permissionsTree =
+          dialogDocument.getElementById("permissionsTree");
+
+        EventUtils.sendString("accept.invalid", dialogWindow);
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("btnAllow"),
+          {},
+          dialogWindow
+        );
+        await new Promise(f => setTimeout(f));
+        Assert.equal(url.value, "", "url input should be cleared");
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          1,
+          "new entry should be added to list"
+        );
+
+        Assert.ok(
+          BrowserTestUtils.is_hidden(
+            dialogDocument.getElementById("btnSession")
+          ),
+          "session button should be hidden"
+        );
+
+        EventUtils.sendString("block.invalid", dialogWindow);
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("btnBlock"),
+          {},
+          dialogWindow
+        );
+        await new Promise(f => setTimeout(f));
+        Assert.equal(url.value, "", "url input should be cleared");
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          2,
+          "new entry should be added to list"
+        );
+
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("btnApplyChanges"),
+          {},
+          dialogWindow
+        );
+      },
+    }
+  );
+  let remoteContentExceptions = prefsDocument.getElementById(
+    "remoteContentExceptions"
+  );
+  EventUtils.synthesizeMouseAtCenter(remoteContentExceptions, {}, prefsWindow);
+  await dialogPromise;
+
+  // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+  let acceptURI = Services.io.newURI("http://accept.invalid/");
+  let acceptPrincipal = Services.scriptSecurityManager.createContentPrincipal(
+    acceptURI,
+    {}
+  );
+  Assert.equal(
+    Services.perms.testPermissionFromPrincipal(acceptPrincipal, "image"),
+    Ci.nsIPermissionManager.ALLOW_ACTION,
+    "accept permission should exist for accept.invalid"
+  );
+
+  // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+  let blockURI = Services.io.newURI("http://block.invalid/");
+  let blockPrincipal = Services.scriptSecurityManager.createContentPrincipal(
+    blockURI,
+    {}
+  );
+  Assert.equal(
+    Services.perms.testPermissionFromPrincipal(blockPrincipal, "image"),
+    Ci.nsIPermissionManager.DENY_ACTION,
+    "block permission should exist for block.invalid"
+  );
+
+  dialogPromise = BrowserTestUtils.promiseAlertDialogOpen(
+    undefined,
+    "chrome://messenger/content/preferences/permissions.xhtml",
+    {
+      isSubDialog: true,
+      async callback(dialogWindow) {
+        await TestUtils.waitForCondition(
+          () => Services.focus.focusedWindow == dialogWindow,
+          "waiting for subdialog to be focused"
+        );
+
+        const dialogDocument = dialogWindow.document;
+        const permissionsTree =
+          dialogDocument.getElementById("permissionsTree");
+
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          2,
+          "list should be populated"
+        );
+
+        permissionsTree.view.selection.select(0);
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("removePermission"),
+          {},
+          dialogWindow
+        );
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          1,
+          "row should be removed from list"
+        );
+
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("removeAllPermissions"),
+          {},
+          dialogWindow
+        );
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          0,
+          "row should be removed from list"
+        );
+
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("btnApplyChanges"),
+          {},
+          dialogWindow
+        );
+      },
+    }
+  );
+  EventUtils.synthesizeMouseAtCenter(remoteContentExceptions, {}, prefsWindow);
+  await dialogPromise;
+
+  Assert.equal(
+    Services.perms.testPermissionFromPrincipal(acceptPrincipal, "image"),
+    Ci.nsIPermissionManager.UNKNOWN_ACTION,
+    "permission should be removed for accept.invalid"
+  );
+  Assert.equal(
+    Services.perms.testPermissionFromPrincipal(blockPrincipal, "image"),
+    Ci.nsIPermissionManager.UNKNOWN_ACTION,
+    "permission should be removed for block.invalid"
+  );
+
+  await closePrefsTab();
+});
+
+add_task(async function testCookiesDialog() {
+  const { prefsDocument, prefsWindow } = await openNewPrefsTab("panePrivacy");
+
+  let dialogPromise = BrowserTestUtils.promiseAlertDialogOpen(
+    undefined,
+    "chrome://messenger/content/preferences/permissions.xhtml",
+    {
+      isSubDialog: true,
+      async callback(dialogWindow) {
+        await TestUtils.waitForCondition(
+          () => Services.focus.focusedWindow == dialogWindow,
+          "waiting for subdialog to be focused"
+        );
+
+        const dialogDocument = dialogWindow.document;
+        const url = dialogDocument.getElementById("url");
+        const permissionsTree =
+          dialogDocument.getElementById("permissionsTree");
+
+        EventUtils.sendString("accept.invalid", dialogWindow);
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("btnAllow"),
+          {},
+          dialogWindow
+        );
+        await new Promise(f => setTimeout(f));
+        Assert.equal(url.value, "", "url input should be cleared");
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          1,
+          "new entry should be added to list"
+        );
+
+        EventUtils.sendString("session.invalid", dialogWindow);
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("btnSession"),
+          {},
+          dialogWindow
+        );
+        await new Promise(f => setTimeout(f));
+        Assert.equal(url.value, "", "url input should be cleared");
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          2,
+          "new entry should be added to list"
+        );
+
+        EventUtils.sendString("block.invalid", dialogWindow);
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("btnBlock"),
+          {},
+          dialogWindow
+        );
+        await new Promise(f => setTimeout(f));
+        Assert.equal(url.value, "", "url input should be cleared");
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          3,
+          "new entry should be added to list"
+        );
+
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("btnApplyChanges"),
+          {},
+          dialogWindow
+        );
+      },
+    }
+  );
+  let cookieExceptions = prefsDocument.getElementById("cookieExceptions");
+  EventUtils.synthesizeMouseAtCenter(cookieExceptions, {}, prefsWindow);
+  await dialogPromise;
+
+  // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+  let acceptURI = Services.io.newURI("http://accept.invalid/");
+  let acceptPrincipal = Services.scriptSecurityManager.createContentPrincipal(
+    acceptURI,
+    {}
+  );
+  Assert.equal(
+    Services.perms.testPermissionFromPrincipal(acceptPrincipal, "cookie"),
+    Ci.nsIPermissionManager.ALLOW_ACTION,
+    "accept permission should exist for accept.invalid"
+  );
+
+  // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+  let sessionURI = Services.io.newURI("http://session.invalid/");
+  let sessionPrincipal = Services.scriptSecurityManager.createContentPrincipal(
+    sessionURI,
+    {}
+  );
+  Assert.equal(
+    Services.perms.testPermissionFromPrincipal(sessionPrincipal, "cookie"),
+    Ci.nsICookiePermission.ACCESS_SESSION,
+    "session permission should exist for session.invalid"
+  );
+
+  // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+  let blockURI = Services.io.newURI("http://block.invalid/");
+  let blockPrincipal = Services.scriptSecurityManager.createContentPrincipal(
+    blockURI,
+    {}
+  );
+  Assert.equal(
+    Services.perms.testPermissionFromPrincipal(blockPrincipal, "cookie"),
+    Ci.nsIPermissionManager.DENY_ACTION,
+    "block permission should exist for block.invalid"
+  );
+
+  dialogPromise = BrowserTestUtils.promiseAlertDialogOpen(
+    undefined,
+    "chrome://messenger/content/preferences/permissions.xhtml",
+    {
+      isSubDialog: true,
+      async callback(dialogWindow) {
+        await TestUtils.waitForCondition(
+          () => Services.focus.focusedWindow == dialogWindow,
+          "waiting for subdialog to be focused"
+        );
+
+        const dialogDocument = dialogWindow.document;
+        const permissionsTree =
+          dialogDocument.getElementById("permissionsTree");
+
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          3,
+          "list should be populated"
+        );
+
+        permissionsTree.view.selection.select(0);
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("removePermission"),
+          {},
+          dialogWindow
+        );
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          2,
+          "row should be removed from list"
+        );
+
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("removeAllPermissions"),
+          {},
+          dialogWindow
+        );
+        Assert.equal(
+          permissionsTree.view.rowCount,
+          0,
+          "row should be removed from list"
+        );
+
+        EventUtils.synthesizeMouseAtCenter(
+          dialogDocument.getElementById("btnApplyChanges"),
+          {},
+          dialogWindow
+        );
+      },
+    }
+  );
+  EventUtils.synthesizeMouseAtCenter(cookieExceptions, {}, prefsWindow);
+  await dialogPromise;
+
+  Assert.equal(
+    Services.perms.testPermissionFromPrincipal(acceptPrincipal, "cookie"),
+    Ci.nsIPermissionManager.UNKNOWN_ACTION,
+    "permission should be removed for accept.invalid"
+  );
+  Assert.equal(
+    Services.perms.testPermissionFromPrincipal(sessionPrincipal, "cookie"),
+    Ci.nsIPermissionManager.UNKNOWN_ACTION,
+    "permission should be removed for session.invalid"
+  );
+  Assert.equal(
+    Services.perms.testPermissionFromPrincipal(blockPrincipal, "cookie"),
+    Ci.nsIPermissionManager.UNKNOWN_ACTION,
+    "permission should be removed for block.invalid"
+  );
+
+  await closePrefsTab();
+});
diff --git a/comm/mail/components/preferences/test/browser/browser_sync.js b/comm/mail/components/preferences/test/browser/browser_sync.js
new file mode 100644
index 0000000000..108695ebb5
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/browser_sync.js
@@ -0,0 +1,419 @@
+/* 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 { MockRegistrar } = ChromeUtils.importESModule(
+  "resource://testing-common/MockRegistrar.sys.mjs"
+);
+
+const { FxAccounts } = ChromeUtils.importESModule(
+  "resource://gre/modules/FxAccounts.sys.mjs"
+);
+FxAccounts.config.promiseConnectAccountURI = entryPoint =>
+  `https://example.org/?page=connect&entryPoint=${entryPoint}`;
+FxAccounts.config.promiseManageURI = entryPoint =>
+  `https://example.org/?page=manage&entryPoint=${entryPoint}`;
+FxAccounts.config.promiseChangeAvatarURI = entryPoint =>
+  `https://example.org/?page=avatar&entryPoint=${entryPoint}`;
+
+const ALL_ENGINES = [
+  "accounts",
+  "identities",
+  "addressbooks",
+  "calendars",
+  "passwords",
+];
+const PREF_PREFIX = "services.sync.engine";
+
+let prefsWindow, prefsDocument, tabmail;
+
+add_setup(async function () {
+  for (let engine of ALL_ENGINES) {
+    Services.prefs.setBoolPref(`${PREF_PREFIX}.${engine}`, true);
+  }
+
+  ({ prefsWindow, prefsDocument } = await openNewPrefsTab("paneSync"));
+  tabmail = document.getElementById("tabmail");
+
+  /** @implements {nsIExternalProtocolService} */
+  let mockExternalProtocolService = {
+    QueryInterface: ChromeUtils.generateQI(["nsIExternalProtocolService"]),
+    externalProtocolHandlerExists(protocolScheme) {},
+    isExposedProtocol(protocolScheme) {},
+    loadURI(uri, windowContext) {
+      Assert.report(
+        true,
+        undefined,
+        undefined,
+        `should not be opening ${uri.spec} in an external browser`
+      );
+    },
+  };
+
+  let mockExternalProtocolServiceCID = MockRegistrar.register(
+    "@mozilla.org/uriloader/external-protocol-service;1",
+    mockExternalProtocolService
+  );
+  registerCleanupFunction(() => {
+    MockRegistrar.unregister(mockExternalProtocolServiceCID);
+  });
+});
+
+add_task(async function testSectionStates() {
+  let noFxaAccount = prefsDocument.getElementById("noFxaAccount");
+  let hasFxaAccount = prefsDocument.getElementById("hasFxaAccount");
+  let accountStates = [noFxaAccount, hasFxaAccount];
+
+  let fxaLoginUnverified = prefsDocument.getElementById("fxaLoginUnverified");
+  let fxaLoginRejected = prefsDocument.getElementById("fxaLoginRejected");
+  let fxaLoginVerified = prefsDocument.getElementById("fxaLoginVerified");
+  let loginStates = [fxaLoginUnverified, fxaLoginRejected, fxaLoginVerified];
+
+  let fxaDeviceInfo = prefsDocument.getElementById("fxaDeviceInfo");
+  let syncConnected = prefsDocument.getElementById("syncConnected");
+  let syncDisconnected = prefsDocument.getElementById("syncDisconnected");
+  let syncStates = [syncConnected, syncDisconnected];
+
+  function assertStateVisible(states, visibleState) {
+    for (let state of states) {
+      let visible = BrowserTestUtils.is_visible(state);
+      Assert.equal(
+        visible,
+        state == visibleState,
+        `${state.id} should be ${state == visibleState ? "visible" : "hidden"}`
+      );
+    }
+  }
+
+  function checkStates({
+    accountState,
+    loginState = null,
+    deviceInfoVisible = false,
+    syncState = null,
+  }) {
+    prefsWindow.gSyncPane.updateWeavePrefs();
+    assertStateVisible(accountStates, accountState);
+    assertStateVisible(loginStates, loginState);
+    Assert.equal(
+      BrowserTestUtils.is_visible(fxaDeviceInfo),
+      deviceInfoVisible,
+      `fxaDeviceInfo should be ${deviceInfoVisible ? "visible" : "hidden"}`
+    );
+    assertStateVisible(syncStates, syncState);
+  }
+
+  async function assertTabOpens(target, expectedURL) {
+    if (typeof target == "string") {
+      target = prefsDocument.getElementById(target);
+    }
+
+    let tabPromise = BrowserTestUtils.waitForEvent(window, "TabOpen");
+    EventUtils.synthesizeMouseAtCenter(target, {}, prefsWindow);
+    await tabPromise;
+    let tab = tabmail.currentTabInfo;
+    await BrowserTestUtils.browserLoaded(tab.browser);
+    Assert.equal(
+      tab.browser.currentURI.spec,
+      `https://example.org/${expectedURL}`,
+      "a tab opened to the correct URL"
+    );
+    tabmail.closeTab(tab);
+  }
+
+  info("No account");
+  Assert.equal(prefsWindow.UIState.get().status, "not_configured");
+  checkStates({ accountState: noFxaAccount });
+
+  // Check clicking the Sign In button opens the connect page in a tab.
+  await assertTabOpens("noFxaSignIn", "?page=connect&entryPoint=");
+
+  // Override the window's UIState object with mock values.
+  let baseState = {
+    email: "test@invalid",
+    displayName: "Testy McTest",
+    avatarURL:
+      "https://example.org/browser/comm/mail/components/preferences/test/browser/files/avatar.png",
+    avatarIsDefault: false,
+  };
+  let mockState;
+  prefsWindow.UIState = {
+    ON_UPDATE: "sync-ui-state:update",
+    STATUS_LOGIN_FAILED: "login_failed",
+    STATUS_NOT_CONFIGURED: "not_configured",
+    STATUS_NOT_VERIFIED: "not_verified",
+    STATUS_SIGNED_IN: "signed_in",
+    get() {
+      return mockState;
+    },
+  };
+
+  info("Login not verified");
+  mockState = { ...baseState, status: "not_verified" };
+  checkStates({
+    accountState: hasFxaAccount,
+    loginState: fxaLoginUnverified,
+    deviceInfoVisible: true,
+  });
+  Assert.deepEqual(
+    await prefsDocument.l10n.getAttributes(
+      prefsDocument.getElementById("fxaAccountMailNotVerified")
+    ),
+    {
+      id: "sync-pane-email-not-verified",
+      args: { userEmail: "test@invalid" },
+    },
+    "email address set correctly"
+  );
+
+  // Untested: Resend and remove account buttons.
+
+  info("Login rejected");
+  mockState = { ...baseState, status: "login_failed" };
+  checkStates({
+    accountState: hasFxaAccount,
+    loginState: fxaLoginRejected,
+    deviceInfoVisible: true,
+  });
+  Assert.deepEqual(
+    await prefsDocument.l10n.getAttributes(
+      prefsDocument.getElementById("fxaAccountLoginRejected")
+    ),
+    {
+      id: "sync-signedin-login-failure",
+      args: { userEmail: "test@invalid" },
+    },
+    "email address set correctly"
+  );
+
+  // Untested: Sign in and remove account buttons.
+
+  info("Logged in, sync disabled");
+  mockState = { ...baseState, status: "verified", syncEnabled: false };
+  checkStates({
+    accountState: hasFxaAccount,
+    loginState: fxaLoginVerified,
+    deviceInfoVisible: true,
+    syncState: syncDisconnected,
+  });
+  let photo = fxaLoginVerified.querySelector(".contact-photo");
+  Assert.equal(
+    photo.src,
+    "https://example.org/browser/comm/mail/components/preferences/test/browser/files/avatar.png",
+    "avatar image set correctly"
+  );
+
+  // Check clicking the avatar image opens the avatar page in a tab.
+  await assertTabOpens(photo, "?page=avatar&entryPoint=preferences");
+
+  Assert.equal(
+    prefsDocument.getElementById("fxaDisplayName").textContent,
+    "Testy McTest",
+    "display name set correctly"
+  );
+  Assert.equal(
+    prefsDocument.getElementById("fxaEmailAddress").textContent,
+    "test@invalid",
+    "email address set correctly"
+  );
+
+  // Check clicking the management link opens the management page in a tab.
+  await assertTabOpens("verifiedManage", "?page=manage&entryPoint=preferences");
+
+  // Untested: Sign out button.
+
+  info("Device name section");
+  let deviceNameInput = prefsDocument.getElementById("fxaDeviceNameInput");
+  let deviceNameCancel = prefsDocument.getElementById("fxaDeviceNameCancel");
+  let deviceNameSave = prefsDocument.getElementById("fxaDeviceNameSave");
+  let deviceNameChange = prefsDocument.getElementById(
+    "fxaDeviceNameChangeDeviceName"
+  );
+  Assert.ok(deviceNameInput.readOnly, "input is read-only");
+  Assert.ok(
+    BrowserTestUtils.is_hidden(deviceNameCancel),
+    "cancel button is hidden"
+  );
+  Assert.ok(
+    BrowserTestUtils.is_hidden(deviceNameSave),
+    "save button is hidden"
+  );
+  Assert.ok(
+    BrowserTestUtils.is_visible(deviceNameChange),
+    "change button is visible"
+  );
+
+  EventUtils.synthesizeMouseAtCenter(deviceNameChange, {}, prefsWindow);
+  Assert.ok(!deviceNameInput.readOnly, "input is writeable");
+  Assert.equal(prefsDocument.activeElement, deviceNameInput, "input is active");
+  Assert.ok(
+    BrowserTestUtils.is_visible(deviceNameCancel),
+    "cancel button is visible"
+  );
+  Assert.ok(
+    BrowserTestUtils.is_visible(deviceNameSave),
+    "save button is visible"
+  );
+  Assert.ok(
+    BrowserTestUtils.is_hidden(deviceNameChange),
+    "change button is hidden"
+  );
+
+  EventUtils.synthesizeMouseAtCenter(deviceNameCancel, {}, prefsWindow);
+  Assert.ok(deviceNameInput.readOnly, "input is read-only");
+  Assert.ok(
+    BrowserTestUtils.is_hidden(deviceNameCancel),
+    "cancel button is hidden"
+  );
+  Assert.ok(
+    BrowserTestUtils.is_hidden(deviceNameSave),
+    "save button is hidden"
+  );
+  Assert.ok(
+    BrowserTestUtils.is_visible(deviceNameChange),
+    "change button is visible"
+  );
+
+  // Check the turn on sync button works.
+  await openEngineDialog({ expectEngines: ALL_ENGINES, button: "syncSetup" });
+
+  info("Logged in, sync enabled");
+  mockState = { ...baseState, status: "verified", syncEnabled: true };
+  checkStates({
+    accountState: hasFxaAccount,
+    loginState: fxaLoginVerified,
+    deviceInfoVisible: true,
+    syncState: syncConnected,
+  });
+
+  // Untested: Sync now button.
+
+  // Check the learn more link opens a tab.
+  await assertTabOpens("enginesLearnMore", "?page=learnMore");
+
+  // Untested: Disconnect button.
+});
+
+add_task(async function testEngines() {
+  function assertEnginesEnabled(...expectedEnabled) {
+    for (let engine of ALL_ENGINES) {
+      let enabled = Services.prefs.getBoolPref(`${PREF_PREFIX}.${engine}`);
+      Assert.equal(
+        enabled,
+        expectedEnabled.includes(engine),
+        `${engine} should be ${
+          expectedEnabled.includes(engine) ? "enabled" : "disabled"
+        }`
+      );
+    }
+  }
+
+  function assertEnginesShown(...expectEngines) {
+    let ENGINES_TO_ITEMS = {
+      accounts: "showSyncAccount",
+      identities: "showSyncIdentity",
+      addressbooks: "showSyncAddress",
+      calendars: "showSyncCalendar",
+      passwords: "showSyncPasswords",
+    };
+    let expectItems = expectEngines.map(engine => ENGINES_TO_ITEMS[engine]);
+    let items = Array.from(
+      prefsDocument.querySelectorAll("#showSyncedList > li:not([hidden])"),
+      li => li.id
+    );
+    Assert.deepEqual(items, expectItems, "enabled engines shown correctly");
+  }
+
+  assertEnginesShown(...ALL_ENGINES);
+  Services.prefs.setBoolPref(`${PREF_PREFIX}.accounts`, false);
+  assertEnginesShown("identities", "addressbooks", "calendars", "passwords");
+  Services.prefs.setBoolPref(`${PREF_PREFIX}.identities`, false);
+  Services.prefs.setBoolPref(`${PREF_PREFIX}.addressbooks`, false);
+  Services.prefs.setBoolPref(`${PREF_PREFIX}.calendars`, false);
+  assertEnginesShown("passwords");
+  Services.prefs.setBoolPref(`${PREF_PREFIX}.passwords`, false);
+  assertEnginesShown();
+
+  info("Checking the engine selection dialog");
+  await openEngineDialog({
+    toggleEngines: ["accounts", "identities", "passwords"],
+  });
+
+  assertEnginesEnabled("accounts", "identities", "passwords");
+  assertEnginesShown("accounts", "identities", "passwords");
+
+  await openEngineDialog({
+    expectEngines: ["accounts", "identities", "passwords"],
+    toggleEngines: ["calendars", "passwords"],
+    action: "cancel",
+  });
+
+  assertEnginesEnabled("accounts", "identities", "passwords");
+  assertEnginesShown("accounts", "identities", "passwords");
+
+  await openEngineDialog({
+    expectEngines: ["accounts", "identities", "passwords"],
+    toggleEngines: ["calendars", "passwords"],
+    action: "accept",
+  });
+
+  assertEnginesEnabled("accounts", "identities", "calendars");
+  assertEnginesShown("accounts", "identities", "calendars");
+
+  Services.prefs.setBoolPref(`${PREF_PREFIX}.addressbooks`, true);
+  Services.prefs.setBoolPref(`${PREF_PREFIX}.passwords`, true);
+  assertEnginesShown(...ALL_ENGINES);
+});
+
+async function openEngineDialog({
+  expectEngines = [],
+  toggleEngines = [],
+  action = "accept",
+  button = "syncChangeOptions",
+}) {
+  const ENGINES_TO_CHECKBOXES = {
+    accounts: "configSyncAccount",
+    identities: "configSyncIdentity",
+    addressbooks: "configSyncAddress",
+    calendars: "configSyncCalendar",
+    passwords: "configSyncPasswords",
+  };
+  let dialogPromise = BrowserTestUtils.promiseAlertDialogOpen(
+    undefined,
+    "chrome://messenger/content/preferences/syncDialog.xhtml",
+    { isSubDialog: true }
+  );
+  EventUtils.synthesizeMouseAtCenter(
+    prefsDocument.getElementById(button),
+    {},
+    prefsWindow
+  );
+  let dialogWindow = await dialogPromise;
+  let dialogDocument = dialogWindow.document;
+  await new Promise(resolve => dialogWindow.setTimeout(resolve));
+
+  let expectItems = expectEngines.map(engine => ENGINES_TO_CHECKBOXES[engine]);
+
+  let checkedItems = Array.from(
+    dialogDocument.querySelectorAll(`input[type="checkbox"]`)
+  )
+    .filter(cb => cb.checked)
+    .map(cb => cb.id);
+  Assert.deepEqual(
+    checkedItems,
+    expectItems,
+    "enabled engines checked correctly"
+  );
+
+  for (let toggleItem of toggleEngines) {
+    let checkbox = dialogDocument.getElementById(
+      ENGINES_TO_CHECKBOXES[toggleItem]
+    );
+    checkbox.checked = !checkbox.checked;
+  }
+
+  EventUtils.synthesizeMouseAtCenter(
+    dialogDocument.querySelector("dialog").getButton(action),
+    {},
+    dialogWindow
+  );
+}
diff --git a/comm/mail/components/preferences/test/browser/files/avatar.png b/comm/mail/components/preferences/test/browser/files/avatar.png
new file mode 100644
index 0000000000..ca0894316a
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/files/avatar.png
diff --git a/comm/mail/components/preferences/test/browser/files/icon.svg b/comm/mail/components/preferences/test/browser/files/icon.svg
new file mode 100644
index 0000000000..6c1a552445
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/files/icon.svg
@@ -0,0 +1,7 @@
+<?xml version="1.0"?>
+<svg xmlns="http://www.w3.org/2000/svg" width="16" height="16">
+  <circle cx="8" cy="8" r="7.5" fill="#ffffff" stroke="#00aa00" stroke-width="1.5"/>
+  <circle cx="5" cy="6" r="1.5" fill="#00aa00"/>
+  <circle cx="11" cy="6" r="1.5" fill="#00aa00"/>
+  <path d="M 12.83,9.30 C 12.24,11.48 10.26,13 8,13 5.75,13 3.74,11.48 3.17,9.29" fill="none" stroke="#00aa00" stroke-width="1.5"/>
+</svg>
diff --git a/comm/mail/components/preferences/test/browser/files/management.html b/comm/mail/components/preferences/test/browser/files/management.html
new file mode 100644
index 0000000000..7e3561d823
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/files/management.html
@@ -0,0 +1,10 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8"/>
+  <title></title>
+</head>
+<body>
+  <a id="a" href="https://www.example.com/">Click me!</a>
+</body>
+</html>
diff --git a/comm/mail/components/preferences/test/browser/head.js b/comm/mail/components/preferences/test/browser/head.js
new file mode 100644
index 0000000000..12cbdb17f1
--- /dev/null
+++ b/comm/mail/components/preferences/test/browser/head.js
@@ -0,0 +1,314 @@
+/* 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-globals-from ../../../../base/content/utilityOverlay.js */
+
+async function openNewPrefsTab(paneID, scrollPaneTo, otherArgs) {
+  let tabmail = document.getElementById("tabmail");
+  let prefsTabMode = tabmail.tabModes.preferencesTab;
+
+  is(prefsTabMode.tabs.length, 0, "Prefs tab is not open");
+
+  let prefsDocument = await new Promise(resolve => {
+    Services.obs.addObserver(function documentLoaded(subject) {
+      if (subject.URL.startsWith("about:preferences")) {
+        Services.obs.removeObserver(documentLoaded, "chrome-document-loaded");
+        subject.ownerGlobal.setTimeout(() => resolve(subject));
+      }
+    }, "chrome-document-loaded");
+    openPreferencesTab(paneID, scrollPaneTo, otherArgs);
+  });
+  ok(prefsDocument.URL.startsWith("about:preferences"), "Prefs tab is open");
+
+  prefsDocument = prefsTabMode.tabs[0].browser.contentDocument;
+  let prefsWindow = prefsDocument.ownerGlobal;
+  prefsWindow.resizeTo(screen.availWidth, screen.availHeight);
+
+  if (paneID) {
+    await new Promise(resolve => prefsWindow.setTimeout(resolve));
+    is(
+      prefsWindow.gLastCategory.category,
+      paneID,
+      `Selected pane is ${paneID}`
+    );
+  } else {
+    // If we don't wait here for other scripts to run, they
+    // could be in a bad state if our test closes the tab.
+    await new Promise(resolve => prefsWindow.setTimeout(resolve));
+  }
+
+  registerCleanupOnce();
+
+  await new Promise(resolve => prefsWindow.setTimeout(resolve));
+  let container = prefsDocument.getElementById("preferencesContainer");
+  if (scrollPaneTo && container.scrollHeight > container.clientHeight) {
+    Assert.greater(
+      container.scrollTop,
+      0,
+      "Prefs page did scroll when it was supposed to"
+    );
+  }
+  return { prefsDocument, prefsWindow };
+}
+
+async function openExistingPrefsTab(paneID, scrollPaneTo, otherArgs) {
+  let tabmail = document.getElementById("tabmail");
+  let prefsTabMode = tabmail.tabModes.preferencesTab;
+
+  is(prefsTabMode.tabs.length, 1, "Prefs tab is open");
+
+  let prefsDocument = prefsTabMode.tabs[0].browser.contentDocument;
+  let prefsWindow = prefsDocument.ownerGlobal;
+  prefsWindow.resizeTo(screen.availWidth, screen.availHeight);
+
+  if (paneID && prefsWindow.gLastCategory.category != paneID) {
+    openPreferencesTab(paneID, scrollPaneTo, otherArgs);
+  }
+
+  await new Promise(resolve => prefsWindow.setTimeout(resolve));
+  is(prefsWindow.gLastCategory.category, paneID, `Selected pane is ${paneID}`);
+
+  if (scrollPaneTo) {
+    Assert.greater(
+      prefsDocument.getElementById("preferencesContainer").scrollTop,
+      0,
+      "Prefs page did scroll when it was supposed to"
+    );
+  }
+
+  registerCleanupOnce();
+  return { prefsDocument, prefsWindow };
+}
+
+function registerCleanupOnce() {
+  if (registerCleanupOnce.alreadyRegistered) {
+    return;
+  }
+  registerCleanupFunction(closePrefsTab);
+  registerCleanupOnce.alreadyRegistered = true;
+}
+
+async function closePrefsTab() {
+  info("Closing prefs tab");
+  let tabmail = document.getElementById("tabmail");
+  let prefsTab = tabmail.tabModes.preferencesTab.tabs[0];
+  if (prefsTab) {
+    tabmail.closeTab(prefsTab);
+  }
+}
+
+/**
+ * Tests a checkbox sets the preference is set in the right state when the preferences tab opens,
+ * that the preference it relates to is set properly, and any UI elements that should be disabled
+ * by it are disabled.
+ *
+ * Each of the tests arguments is an object describing a test, containing:
+ *   checkboxID - the ID of the checkbox to test
+ *   pref - the name of a preference,
+ *   prefValues - an array of two values: pref value when not checked, pref value when checked
+ *                (optional, defaults to [false, true])
+ *   enabledElements - an array of CSS selectors (optional)
+ *   enabledInverted - if the elements should be disabled when the checkbox is checked (optional)
+ *   unaffectedElements - array of CSS selectors that should not be affected by
+ *                        the toggling of the checkbox.
+ */
+async function testCheckboxes(paneID, scrollPaneTo, ...tests) {
+  for (let initiallyChecked of [true, false]) {
+    info(`Opening ${paneID} with prefs set to ${initiallyChecked}`);
+
+    for (let test of tests) {
+      let wantedValue = initiallyChecked;
+      if (test.prefValues) {
+        wantedValue = wantedValue ? test.prefValues[1] : test.prefValues[0];
+      }
+      if (typeof wantedValue == "number") {
+        Services.prefs.setIntPref(test.pref, wantedValue);
+      } else {
+        Services.prefs.setBoolPref(test.pref, wantedValue);
+      }
+    }
+
+    let { prefsDocument, prefsWindow } = await openNewPrefsTab(
+      paneID,
+      scrollPaneTo
+    );
+
+    let testUIState = function (test, checked) {
+      let wantedValue = checked;
+      if (test.prefValues) {
+        wantedValue = wantedValue ? test.prefValues[1] : test.prefValues[0];
+      }
+      let checkbox = prefsDocument.getElementById(test.checkboxID);
+      is(
+        checkbox.checked,
+        checked,
+        wantedValue,
+        "Checkbox " + (checked ? "is" : "isn't") + " checked"
+      );
+      if (typeof wantedValue == "number") {
+        is(
+          Services.prefs.getIntPref(test.pref, -999),
+          wantedValue,
+          `Pref is ${wantedValue}`
+        );
+      } else {
+        is(
+          Services.prefs.getBoolPref(test.pref),
+          wantedValue,
+          `Pref is ${wantedValue}`
+        );
+      }
+
+      if (test.enabledElements) {
+        let disabled = checked;
+        if (test.enabledInverted) {
+          disabled = !disabled;
+        }
+        for (let selector of test.enabledElements) {
+          let elements = prefsDocument.querySelectorAll(selector);
+          ok(
+            elements.length >= 1,
+            `At least one element matched '${selector}'`
+          );
+          for (let element of elements) {
+            is(
+              element.disabled,
+              !disabled,
+              "Element " + (disabled ? "isn't" : "is") + " disabled"
+            );
+          }
+        }
+      }
+    };
+
+    let testUnaffected = function (ids, states) {
+      ids.forEach((sel, index) => {
+        let isOk = prefsDocument.querySelector(sel).disabled === states[index];
+        is(isOk, true, `Element "${sel}" is unaffected`);
+      });
+    };
+
+    for (let test of tests) {
+      info(`Checking ${test.checkboxID}`);
+
+      let unaffectedSelectors = test.unaffectedElements || [];
+      let unaffectedStates = unaffectedSelectors.map(
+        sel => prefsDocument.querySelector(sel).disabled
+      );
+
+      let checkbox = prefsDocument.getElementById(test.checkboxID);
+      checkbox.scrollIntoView(false);
+      testUIState(test, initiallyChecked);
+
+      EventUtils.synthesizeMouseAtCenter(checkbox, {}, prefsWindow);
+      testUIState(test, !initiallyChecked);
+      testUnaffected(unaffectedSelectors, unaffectedStates);
+
+      EventUtils.synthesizeMouseAtCenter(checkbox, {}, prefsWindow);
+      testUIState(test, initiallyChecked);
+      testUnaffected(unaffectedSelectors, unaffectedStates);
+    }
+
+    await closePrefsTab();
+  }
+}
+
+/**
+ * Tests a set of radio buttons is in the right state when the preferences tab opens, and when
+ * the selected button changes that the preference it relates to is set properly, and any related
+ * UI elements that should be disabled are disabled.
+ *
+ * Each of the tests arguments is an object describing a test, containing:
+ *   pref - the name of an integer preference,
+ *   states - an array with each element describing a radio button:
+ *     id - the ID of the button to test,
+ *     prefValue - the value the pref should be set to
+ *     enabledElements - an array of CSS selectors to elements that should be enabled when this
+ *                       radio button is selected (optional)
+ */
+async function testRadioButtons(paneID, scrollPaneTo, ...tests) {
+  for (let { pref, states } of tests) {
+    for (let initialState of states) {
+      info(`Opening ${paneID} with ${pref} set to ${initialState.prefValue}`);
+
+      if (typeof initialState.prefValue == "number") {
+        Services.prefs.setIntPref(pref, initialState.prefValue);
+      } else if (typeof initialState.prefValue == "boolean") {
+        Services.prefs.setBoolPref(pref, initialState.prefValue);
+      } else {
+        Services.prefs.setCharPref(pref, initialState.prefValue);
+      }
+
+      let { prefsDocument, prefsWindow } = await openNewPrefsTab(
+        paneID,
+        scrollPaneTo
+      );
+
+      let testUIState = function (currentState) {
+        info(`Testing with ${pref} set to ${currentState.prefValue}`);
+        for (let state of states) {
+          let isCurrentState = state == currentState;
+          let radio = prefsDocument.getElementById(state.id);
+          is(radio.selected, isCurrentState, `${state.id}.selected`);
+
+          if (state.enabledElements) {
+            for (let selector of state.enabledElements) {
+              let elements = prefsDocument.querySelectorAll(selector);
+              ok(
+                elements.length >= 1,
+                `At least one element matched '${selector}'`
+              );
+              for (let element of elements) {
+                is(
+                  element.disabled,
+                  !isCurrentState,
+                  "Element " + (isCurrentState ? "isn't" : "is") + " disabled"
+                );
+              }
+            }
+          }
+        }
+        if (typeof initialState.prefValue == "number") {
+          is(
+            Services.prefs.getIntPref(pref, -999),
+            currentState.prefValue,
+            `Pref is ${currentState.prefValue}`
+          );
+        } else if (typeof initialState.prefValue == "boolean") {
+          is(
+            Services.prefs.getBoolPref(pref),
+            currentState.prefValue,
+            `Pref is ${currentState.prefValue}`
+          );
+        } else {
+          is(
+            Services.prefs.getCharPref(pref, "FAKE VALUE"),
+            currentState.prefValue,
+            `Pref is ${currentState.prefValue}`
+          );
+        }
+      };
+
+      // Check the initial setup is correct.
+      testUIState(initialState);
+      // Cycle through possible values, checking each one.
+      for (let state of states) {
+        if (state == initialState) {
+          continue;
+        }
+        let radio = prefsDocument.getElementById(state.id);
+        radio.scrollIntoView(false);
+        EventUtils.synthesizeMouseAtCenter(radio, {}, prefsWindow);
+        testUIState(state);
+      }
+      // Go back to the initial value.
+      let initialRadio = prefsDocument.getElementById(initialState.id);
+      initialRadio.scrollIntoView(false);
+      EventUtils.synthesizeMouseAtCenter(initialRadio, {}, prefsWindow);
+      testUIState(initialState);
+
+      await closePrefsTab();
+    }
+  }
+}