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

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

1 files changed, 2021 insertions, 0 deletions

diff --git a/toolkit/modules/PopupNotifications.sys.mjs b/toolkit/modules/PopupNotifications.sys.mjs
new file mode 100644
index 0000000000..ca51346625
--- /dev/null
+++ b/toolkit/modules/PopupNotifications.sys.mjs
@@ -0,0 +1,2021 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import { PrivateBrowsingUtils } from "resource://gre/modules/PrivateBrowsingUtils.sys.mjs";
+
+import { PromiseUtils } from "resource://gre/modules/PromiseUtils.sys.mjs";
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+
+const NOTIFICATION_EVENT_DISMISSED = "dismissed";
+const NOTIFICATION_EVENT_REMOVED = "removed";
+const NOTIFICATION_EVENT_SHOWING = "showing";
+const NOTIFICATION_EVENT_SHOWN = "shown";
+const NOTIFICATION_EVENT_SWAPPING = "swapping";
+
+const ICON_SELECTOR = ".notification-anchor-icon";
+const ICON_ATTRIBUTE_SHOWING = "showing";
+const ICON_ANCHOR_ATTRIBUTE = "popupnotificationanchor";
+
+const PREF_SECURITY_DELAY = "security.notification_enable_delay";
+const FULLSCREEN_TRANSITION_TIME_SHOWN_OFFSET_MS = 2000;
+
+// Enumerated values for the POPUP_NOTIFICATION_STATS telemetry histogram.
+const TELEMETRY_STAT_OFFERED = 0;
+const TELEMETRY_STAT_ACTION_1 = 1;
+const TELEMETRY_STAT_ACTION_2 = 2;
+// const TELEMETRY_STAT_ACTION_3 = 3;
+const TELEMETRY_STAT_ACTION_LAST = 4;
+// const TELEMETRY_STAT_DISMISSAL_CLICK_ELSEWHERE = 5;
+const TELEMETRY_STAT_REMOVAL_LEAVE_PAGE = 6;
+// const TELEMETRY_STAT_DISMISSAL_CLOSE_BUTTON = 7;
+const TELEMETRY_STAT_OPEN_SUBMENU = 10;
+const TELEMETRY_STAT_LEARN_MORE = 11;
+
+const TELEMETRY_STAT_REOPENED_OFFSET = 20;
+const lazy = {};
+
+XPCOMUtils.defineLazyPreferenceGetter(lazy, "buttonDelay", PREF_SECURITY_DELAY);
+
+var popupNotificationsMap = new WeakMap();
+var gNotificationParents = new WeakMap();
+
+function getAnchorFromBrowser(aBrowser, aAnchorID) {
+  let attrPrefix = aAnchorID ? aAnchorID.replace("notification-icon", "") : "";
+  let anchor =
+    aBrowser.getAttribute(attrPrefix + ICON_ANCHOR_ATTRIBUTE) ||
+    aBrowser[attrPrefix + ICON_ANCHOR_ATTRIBUTE] ||
+    aBrowser.getAttribute(ICON_ANCHOR_ATTRIBUTE) ||
+    aBrowser[ICON_ANCHOR_ATTRIBUTE];
+  if (anchor) {
+    if (ChromeUtils.getClassName(anchor) == "XULElement") {
+      return anchor;
+    }
+    return aBrowser.ownerDocument.getElementById(anchor);
+  }
+  return null;
+}
+
+/**
+ * Given a DOM node inside a <popupnotification>, return the parent <popupnotification>.
+ */
+function getNotificationFromElement(aElement) {
+  return aElement.closest("popupnotification");
+}
+
+/**
+ * Notification object describes a single popup notification.
+ *
+ * @see PopupNotifications.show()
+ */
+function Notification(
+  id,
+  message,
+  anchorID,
+  mainAction,
+  secondaryActions,
+  browser,
+  owner,
+  options
+) {
+  this.id = id;
+  this.message = message;
+  this.anchorID = anchorID;
+  this.mainAction = mainAction;
+  this.secondaryActions = secondaryActions || [];
+  this.browser = browser;
+  this.owner = owner;
+  this.options = options || {};
+
+  this._dismissed = false;
+  // Will become a boolean when manually toggled by the user.
+  this._checkboxChecked = null;
+  this.wasDismissed = false;
+  this.recordedTelemetryStats = new Set();
+  this.isPrivate = PrivateBrowsingUtils.isWindowPrivate(
+    this.browser.ownerGlobal
+  );
+  this.timeCreated = this.owner.window.performance.now();
+}
+
+Notification.prototype = {
+  id: null,
+  message: null,
+  anchorID: null,
+  mainAction: null,
+  secondaryActions: null,
+  browser: null,
+  owner: null,
+  options: null,
+  timeShown: null,
+
+  /**
+   * Indicates whether the notification is currently dismissed.
+   */
+  set dismissed(value) {
+    this._dismissed = value;
+    if (value) {
+      // Keep the dismissal into account when recording telemetry.
+      this.wasDismissed = true;
+    }
+  },
+  get dismissed() {
+    return this._dismissed;
+  },
+
+  /**
+   * Removes the notification and updates the popup accordingly if needed.
+   */
+  remove: function Notification_remove() {
+    this.owner.remove(this);
+  },
+
+  get anchorElement() {
+    let iconBox = this.owner.iconBox;
+
+    let anchorElement = getAnchorFromBrowser(this.browser, this.anchorID);
+    if (!iconBox) {
+      return anchorElement;
+    }
+
+    if (!anchorElement && this.anchorID) {
+      anchorElement = iconBox.querySelector("#" + this.anchorID);
+    }
+
+    // Use a default anchor icon if it's available
+    if (!anchorElement) {
+      anchorElement =
+        iconBox.querySelector("#default-notification-icon") || iconBox;
+    }
+
+    return anchorElement;
+  },
+
+  reshow() {
+    this.owner._reshowNotifications(this.anchorElement, this.browser);
+  },
+
+  /**
+   * Adds a value to the specified histogram, that must be keyed by ID.
+   */
+  _recordTelemetry(histogramId, value) {
+    if (this.isPrivate && !this.options.recordTelemetryInPrivateBrowsing) {
+      // The reason why we don't record telemetry in private windows is because
+      // the available actions can be different from regular mode. The main
+      // difference is that all of the persistent permission options like
+      // "Always remember" aren't there, so they really need to be handled
+      // separately to avoid skewing results. For notifications with the same
+      // choices, there would be no reason not to record in private windows as
+      // well, but it's just simpler to use the same check for everything.
+      return;
+    }
+    let histogram = Services.telemetry.getKeyedHistogramById(histogramId);
+    histogram.add("(all)", value);
+    histogram.add(this.id, value);
+  },
+
+  /**
+   * Adds an enumerated value to the POPUP_NOTIFICATION_STATS histogram,
+   * ensuring that it is recorded at most once for each distinct Notification.
+   *
+   * Statistics for reopened notifications are recorded in separate buckets.
+   *
+   * @param value
+   *        One of the TELEMETRY_STAT_ constants.
+   */
+  _recordTelemetryStat(value) {
+    if (this.wasDismissed) {
+      value += TELEMETRY_STAT_REOPENED_OFFSET;
+    }
+    if (!this.recordedTelemetryStats.has(value)) {
+      this.recordedTelemetryStats.add(value);
+      this._recordTelemetry("POPUP_NOTIFICATION_STATS", value);
+    }
+  },
+};
+
+/**
+ * The PopupNotifications object manages popup notifications for a given browser
+ * window.
+ * @param tabbrowser
+ *        window's TabBrowser. Used to observe tab switching events and
+ *        for determining the active browser element.
+ * @param panel
+ *        The <xul:panel/> element to use for notifications. The panel is
+ *        populated with <popupnotification> children and displayed it as
+ *        needed.
+ * @param iconBox
+ *        Reference to a container element that should be hidden or
+ *        unhidden when notifications are hidden or shown. It should be the
+ *        parent of anchor elements whose IDs are passed to show().
+ *        It is used as a fallback popup anchor if notifications specify
+ *        invalid or non-existent anchor IDs.
+ * @param options
+ *        An optional object with the following optional properties:
+ *        {
+ *          shouldSuppress:
+ *            If this function returns true, then all notifications are
+ *            suppressed for this window. This state is checked on construction
+ *            and when the "anchorVisibilityChange" method is called.
+ *          getVisibleAnchorElement(anchorElement):
+ *            A function which takes an anchor element as input and should return
+ *            either the anchor if it's visible, a fallback anchor element, or if
+ *            no fallback exists, a null element.
+ *        }
+ */
+export function PopupNotifications(tabbrowser, panel, iconBox, options = {}) {
+  if (!tabbrowser) {
+    throw new Error("Invalid tabbrowser");
+  }
+  if (iconBox && ChromeUtils.getClassName(iconBox) != "XULElement") {
+    throw new Error("Invalid iconBox");
+  }
+  if (ChromeUtils.getClassName(panel) != "XULPopupElement") {
+    throw new Error("Invalid panel");
+  }
+
+  this._shouldSuppress = options.shouldSuppress || (() => false);
+  this._suppress = this._shouldSuppress();
+
+  this._getVisibleAnchorElement = options.getVisibleAnchorElement;
+
+  this.window = tabbrowser.ownerGlobal;
+  this.panel = panel;
+  this.tabbrowser = tabbrowser;
+  this.iconBox = iconBox;
+
+  this.panel.addEventListener("popuphidden", this, true);
+  this.panel.addEventListener("popuppositioned", this);
+  this.panel.classList.add("popup-notification-panel", "panel-no-padding");
+
+  // This listener will be attached to the chrome window whenever a notification
+  // is showing, to allow the user to dismiss notifications using the escape key.
+  this._handleWindowKeyPress = aEvent => {
+    if (aEvent.keyCode != aEvent.DOM_VK_ESCAPE) {
+      return;
+    }
+
+    // Esc key cancels the topmost notification, if there is one.
+    let notification = this.panel.firstElementChild;
+    if (!notification) {
+      return;
+    }
+
+    let doc = this.window.document;
+    let focusedElement = Services.focus.focusedElement;
+
+    // If the chrome window has a focused element, let it handle the ESC key instead.
+    if (
+      !focusedElement ||
+      focusedElement == doc.body ||
+      focusedElement == this.tabbrowser.selectedBrowser ||
+      // Ignore focused elements inside the notification.
+      notification.contains(focusedElement)
+    ) {
+      let escAction = notification.notification.options.escAction;
+      this._onButtonEvent(aEvent, escAction, "esc-press", notification);
+      // Without this preventDefault call, the event will be sent to the content page
+      // and our event listener might be called again after receiving a reply from
+      // the content process, which could accidentally dismiss another notification.
+      aEvent.preventDefault();
+    }
+  };
+
+  let documentElement = this.window.document.documentElement;
+  let locationBarHidden = documentElement
+    .getAttribute("chromehidden")
+    .includes("location");
+  let isFullscreen = !!this.window.document.fullscreenElement;
+
+  this.panel.setAttribute("followanchor", !locationBarHidden && !isFullscreen);
+
+  // There are no anchor icons in DOM fullscreen mode, but we would
+  // still like to show the popup notification. To avoid an infinite
+  // loop of showing and hiding, we have to disable followanchor
+  // (which hides the element without an anchor) in fullscreen.
+  this.window.addEventListener(
+    "MozDOMFullscreen:Entered",
+    () => {
+      this.panel.setAttribute("followanchor", "false");
+    },
+    true
+  );
+  this.window.addEventListener(
+    "MozDOMFullscreen:Exited",
+    () => {
+      this.panel.setAttribute("followanchor", !locationBarHidden);
+    },
+    true
+  );
+
+  Services.obs.addObserver(this, "fullscreen-transition-start");
+
+  this.window.addEventListener("unload", () => {
+    Services.obs.removeObserver(this, "fullscreen-transition-start");
+  });
+
+  this.window.addEventListener("activate", this, true);
+  if (this.tabbrowser.tabContainer) {
+    this.tabbrowser.tabContainer.addEventListener("TabSelect", this, true);
+
+    this.tabbrowser.tabContainer.addEventListener("TabClose", aEvent => {
+      // If the tab was just closed and we have notifications associated with it,
+      // then the notifications were closed because of the tab removal. We need to
+      // record this event in telemetry and fire the removal callback.
+      this.nextRemovalReason = TELEMETRY_STAT_REMOVAL_LEAVE_PAGE;
+      let notifications = this._getNotificationsForBrowser(
+        aEvent.target.linkedBrowser
+      );
+      for (let notification of notifications) {
+        this._fireCallback(
+          notification,
+          NOTIFICATION_EVENT_REMOVED,
+          this.nextRemovalReason
+        );
+        notification._recordTelemetryStat(this.nextRemovalReason);
+      }
+    });
+  }
+}
+
+PopupNotifications.prototype = {
+  window: null,
+  panel: null,
+  tabbrowser: null,
+
+  _iconBox: null,
+  set iconBox(iconBox) {
+    // Remove the listeners on the old iconBox, if needed
+    if (this._iconBox) {
+      this._iconBox.removeEventListener("click", this);
+      this._iconBox.removeEventListener("keypress", this);
+    }
+    this._iconBox = iconBox;
+    if (iconBox) {
+      iconBox.addEventListener("click", this);
+      iconBox.addEventListener("keypress", this);
+    }
+  },
+  get iconBox() {
+    return this._iconBox;
+  },
+
+  observe(subject, topic) {
+    if (topic == "fullscreen-transition-start") {
+      // Extend security delay if the panel is open.
+      if (this.isPanelOpen) {
+        let notification = this.panel.firstChild?.notification;
+        if (notification) {
+          this._extendSecurityDelay([notification]);
+        }
+      }
+    }
+  },
+
+  /**
+   * Retrieve one or many Notification object/s associated with the browser/ID pair.
+   * @param {string|string[]} id
+   *        The Notification ID or an array of IDs to search for.
+   * @param [browser]
+   *        The browser whose notifications should be searched. If null, the
+   *        currently selected browser's notifications will be searched.
+   *
+   * @returns {Notification|Notification[]|null} If passed a single id, returns the corresponding Notification object, or null if no such
+   *          notification exists.
+   *          If passed an id array, returns an array of Notification objects which match the ids.
+   */
+  getNotification: function PopupNotifications_getNotification(id, browser) {
+    let notifications = this._getNotificationsForBrowser(
+      browser || this.tabbrowser.selectedBrowser
+    );
+    if (Array.isArray(id)) {
+      return notifications.filter(x => id.includes(x.id));
+    }
+    return notifications.find(x => x.id == id) || null;
+  },
+
+  /**
+   * Adds a new popup notification.
+   * @param browser
+   *        The <xul:browser> element associated with the notification. Must not
+   *        be null.
+   * @param id
+   *        A unique ID that identifies the type of notification (e.g.
+   *        "geolocation"). Only one notification with a given ID can be visible
+   *        at a time. If a notification already exists with the given ID, it
+   *        will be replaced.
+   * @param message
+   *        A string containing the text to be displayed as the notification
+   *        header.  The string may optionally contain one or two "<>" as a
+   *        placeholder which is later replaced by a host name or an addon name
+   *        that is formatted to look bold, in which case the options.name
+   *        property (as well as options.secondName if passing a "<>" and a "{}"
+   *        placeholder) needs to be specified. "<>" will be considered as the
+   *        first and "{}" as the second placeholder.
+   * @param anchorID
+   *        The ID of the element that should be used as this notification
+   *        popup's anchor. May be null, in which case the notification will be
+   *        anchored to the iconBox.
+   * @param mainAction
+   *        A JavaScript object literal describing the notification button's
+   *        action. If present, it must have the following properties:
+   *          - label (string): the button's label.
+   *          - accessKey (string): the button's accessKey.
+   *          - callback (function): a callback to be invoked when the button is
+   *            pressed, is passed an object that contains the following fields:
+   *              - checkboxChecked: (boolean) If the optional checkbox is checked.
+   *              - source: (string): the source of the action that initiated the
+   *                callback, either:
+   *                - "button" if popup buttons were directly activated, or
+   *                - "esc-press" if the user pressed the escape key, or
+   *                - "menucommand" if a menu was activated.
+   *          - [optional] dismiss (boolean): If this is true, the notification
+   *            will be dismissed instead of removed after running the callback.
+   *          - [optional] disabled (boolean): If this is true, the button
+   *            will be disabled.
+   *        If null, the notification will have a default "OK" action button
+   *        that can be used to dismiss the popup and secondaryActions will be ignored.
+   * @param secondaryActions
+   *        An optional JavaScript array describing the notification's alternate
+   *        actions. The array should contain objects with the same properties
+   *        as mainAction. These are used to populate the notification button's
+   *        dropdown menu.
+   * @param options
+   *        An options JavaScript object holding additional properties for the
+   *        notification. The following properties are currently supported:
+   *        persistence: An integer. The notification will not automatically
+   *                     dismiss for this many page loads.
+   *        timeout:     A time in milliseconds. The notification will not
+   *                     automatically dismiss before this time.
+   *        persistWhileVisible:
+   *                     A boolean. If true, a visible notification will always
+   *                     persist across location changes.
+   *        persistent:  A boolean. If true, the notification will always
+   *                     persist even across tab and app changes (but not across
+   *                     location changes), until the user accepts or rejects
+   *                     the request. The notification will never be implicitly
+   *                     dismissed.
+   *        dismissed:   Whether the notification should be added as a dismissed
+   *                     notification. Dismissed notifications can be activated
+   *                     by clicking on their anchorElement.
+   *        autofocus:   Whether the notification should be autofocused on
+   *                     showing, stealing focus from any other focused element.
+   *        eventCallback:
+   *                     Callback to be invoked when the notification changes
+   *                     state. The callback's first argument is a string
+   *                     identifying the state change:
+   *                     "dismissed": notification has been dismissed by the
+   *                                  user (e.g. by clicking away or switching
+   *                                  tabs)
+   *                     "removed": notification has been removed (due to
+   *                                location change or user action)
+   *                     "showing": notification is about to be shown
+   *                                (this can be fired multiple times as
+   *                                 notifications are dismissed and re-shown)
+   *                                If the callback returns true, the notification
+   *                                will be dismissed.
+   *                     "shown": notification has been shown (this can be fired
+   *                              multiple times as notifications are dismissed
+   *                              and re-shown)
+   *                     "swapping": the docshell of the browser that created
+   *                                 the notification is about to be swapped to
+   *                                 another browser. A second parameter contains
+   *                                 the browser that is receiving the docshell,
+   *                                 so that the event callback can transfer stuff
+   *                                 specific to this notification.
+   *                                 If the callback returns true, the notification
+   *                                 will be moved to the new browser.
+   *                                 If the callback isn't implemented, returns false,
+   *                                 or doesn't return any value, the notification
+   *                                 will be removed.
+   *        neverShow:   Indicate that no popup should be shown for this
+   *                     notification. Useful for just showing the anchor icon.
+   *        removeOnDismissal:
+   *                     Notifications with this parameter set to true will be
+   *                     removed when they would have otherwise been dismissed
+   *                     (i.e. any time the popup is closed due to user
+   *                     interaction).
+   *        hideClose:   Indicate that the little close button in the corner of
+   *                     the panel should be hidden.
+   *        checkbox:    An object that allows you to add a checkbox and
+   *                     control its behavior with these fields:
+   *                       label:
+   *                         (required) Label to be shown next to the checkbox.
+   *                       checked:
+   *                         (optional) Whether the checkbox should be checked
+   *                         by default. Defaults to false.
+   *                       checkedState:
+   *                         (optional) An object that allows you to customize
+   *                         the notification state when the checkbox is checked.
+   *                           disableMainAction:
+   *                             (optional) Whether the mainAction is disabled.
+   *                             Defaults to false.
+   *                           warningLabel:
+   *                             (optional) A (warning) text that is shown below the
+   *                             checkbox. Pass null to hide.
+   *                       uncheckedState:
+   *                         (optional) An object that allows you to customize
+   *                         the notification state when the checkbox is not checked.
+   *                         Has the same attributes as checkedState.
+   *        popupIconClass:
+   *                     A string. A class (or space separated list of classes)
+   *                     that will be applied to the icon in the popup so that
+   *                     several notifications using the same panel can use
+   *                     different icons.
+   *        popupIconURL:
+   *                     A string. URL of the image to be displayed in the popup.
+   *        learnMoreURL:
+   *                     A string URL. Setting this property will make the
+   *                     prompt display a "Learn More" link that, when clicked,
+   *                     opens the URL in a new tab.
+   *        displayURI:
+   *                     The nsIURI of the page the notification came
+   *                     from. If present, this will be displayed above the message.
+   *                     If the nsIURI represents a file, the path will be displayed,
+   *                     otherwise the hostPort will be displayed.
+   *        name:
+   *                     An optional string formatted to look bold and used in the
+   *                     notifiation description header text. Usually a host name or
+   *                     addon name.
+   *        secondName:
+   *                     An optional string formatted to look bold and used in the
+   *                     notification description header text. Usually a host name or
+   *                     addon name. This is similar to name, and only used in case
+   *                     where message contains a "<>" and a "{}" placeholder. "<>"
+   *                     is considered the first and "{}" is considered the second
+   *                     placeholder.
+   *        escAction:
+   *                     An optional string indicating the action to take when the
+   *                     Esc key is pressed. This should be set to the name of the
+   *                     command to run. If not provided, "secondarybuttoncommand"
+   *                     will be used.
+   *        extraAttr:
+   *                     An optional string value which will be given to the
+   *                     extraAttr attribute on the notification's anchorElement
+   *        popupOptions:
+   *                     An optional object containing popup options passed to
+   *                     `openPopup()` when defined.
+   *        recordTelemetryInPrivateBrowsing:
+   *                     An optional boolean indicating whether popup telemetry
+   *                     should be recorded in private browsing windows. By default,
+   *                     telemetry is NOT recorded in PBM, because the available
+   *                     options for persistent permission notifications are
+   *                     different between normal and PBM windows, potentially
+   *                     skewing the data. But for notifications that do not differ
+   *                     in PBM, this option can be used to ensure that popups in
+   *                     both PBM and normal windows record the same interactions.
+   * @returns the Notification object corresponding to the added notification.
+   */
+  show: function PopupNotifications_show(
+    browser,
+    id,
+    message,
+    anchorID,
+    mainAction,
+    secondaryActions,
+    options
+  ) {
+    function isInvalidAction(a) {
+      return (
+        !a || !(typeof a.callback == "function") || !a.label || !a.accessKey
+      );
+    }
+
+    if (!browser) {
+      throw new Error("PopupNotifications_show: invalid browser");
+    }
+    if (!id) {
+      throw new Error("PopupNotifications_show: invalid ID");
+    }
+    if (mainAction && isInvalidAction(mainAction)) {
+      throw new Error("PopupNotifications_show: invalid mainAction");
+    }
+    if (secondaryActions && secondaryActions.some(isInvalidAction)) {
+      throw new Error("PopupNotifications_show: invalid secondaryActions");
+    }
+
+    let notification = new Notification(
+      id,
+      message,
+      anchorID,
+      mainAction,
+      secondaryActions,
+      browser,
+      this,
+      options
+    );
+
+    if (options) {
+      let escAction = options.escAction;
+      if (
+        escAction != "buttoncommand" &&
+        escAction != "secondarybuttoncommand"
+      ) {
+        escAction = "secondarybuttoncommand";
+      }
+      notification.options.escAction = escAction;
+    }
+
+    if (options && options.dismissed) {
+      notification.dismissed = true;
+    }
+
+    let existingNotification = this.getNotification(id, browser);
+    if (existingNotification) {
+      this._remove(existingNotification);
+    }
+
+    let notifications = this._getNotificationsForBrowser(browser);
+    notifications.push(notification);
+
+    let isActiveBrowser = this._isActiveBrowser(browser);
+    let isActiveWindow = Services.focus.activeWindow == this.window;
+
+    if (isActiveBrowser) {
+      if (isActiveWindow) {
+        // Autofocus if the notification requests focus.
+        if (options && !options.dismissed && options.autofocus) {
+          this.panel.removeAttribute("noautofocus");
+        } else {
+          this.panel.setAttribute("noautofocus", "true");
+        }
+
+        // show panel now
+        this._update(
+          notifications,
+          new Set([notification.anchorElement]),
+          true
+        );
+      } else {
+        // indicate attention and update the icon if necessary
+        if (!notification.dismissed) {
+          this.window.getAttention();
+        }
+        this._updateAnchorIcons(
+          notifications,
+          this._getAnchorsForNotifications(
+            notifications,
+            notification.anchorElement
+          )
+        );
+        this._notify("backgroundShow");
+      }
+    } else {
+      // Notify observers that we're not showing the popup (useful for testing)
+      this._notify("backgroundShow");
+    }
+
+    return notification;
+  },
+
+  /**
+   * Returns true if the notification popup is currently being displayed.
+   */
+  get isPanelOpen() {
+    let panelState = this.panel.state;
+
+    return panelState == "showing" || panelState == "open";
+  },
+
+  /**
+   * Called by the consumer to indicate that the open panel should
+   * temporarily be hidden while the given panel is showing.
+   */
+  suppressWhileOpen(panel) {
+    this._hidePanel().catch(console.error);
+    panel.addEventListener("popuphidden", aEvent => {
+      this._update();
+    });
+  },
+
+  /**
+   * Called by the consumer to indicate that a browser's location has changed,
+   * so that we can update the active notifications accordingly.
+   */
+  locationChange: function PopupNotifications_locationChange(aBrowser) {
+    if (!aBrowser) {
+      throw new Error("PopupNotifications_locationChange: invalid browser");
+    }
+
+    let notifications = this._getNotificationsForBrowser(aBrowser);
+
+    this.nextRemovalReason = TELEMETRY_STAT_REMOVAL_LEAVE_PAGE;
+
+    notifications = notifications.filter(function (notification) {
+      // The persistWhileVisible option allows an open notification to persist
+      // across location changes
+      if (notification.options.persistWhileVisible && this.isPanelOpen) {
+        if (
+          "persistence" in notification.options &&
+          notification.options.persistence
+        ) {
+          notification.options.persistence--;
+        }
+        return true;
+      }
+
+      // The persistence option allows a notification to persist across multiple
+      // page loads
+      if (
+        "persistence" in notification.options &&
+        notification.options.persistence
+      ) {
+        notification.options.persistence--;
+        return true;
+      }
+
+      // The timeout option allows a notification to persist until a certain time
+      if (
+        "timeout" in notification.options &&
+        Date.now() <= notification.options.timeout
+      ) {
+        return true;
+      }
+
+      notification._recordTelemetryStat(this.nextRemovalReason);
+      this._fireCallback(
+        notification,
+        NOTIFICATION_EVENT_REMOVED,
+        this.nextRemovalReason
+      );
+      return false;
+    }, this);
+
+    this._setNotificationsForBrowser(aBrowser, notifications);
+
+    if (this._isActiveBrowser(aBrowser)) {
+      this.anchorVisibilityChange();
+    }
+  },
+
+  /**
+   * Called by the consumer to indicate that the visibility of the notification
+   * anchors may have changed, but the location has not changed. This also
+   * checks whether all notifications are suppressed for this window.
+   *
+   * Calling this method may result in the "showing" and "shown" events for
+   * visible notifications to be invoked even if the anchor has not changed.
+   */
+  anchorVisibilityChange() {
+    let suppress = this._shouldSuppress();
+    if (!suppress) {
+      // If notifications are not suppressed, always update the visibility.
+      this._suppress = false;
+      let notifications = this._getNotificationsForBrowser(
+        this.tabbrowser.selectedBrowser
+      );
+      this._update(
+        notifications,
+        this._getAnchorsForNotifications(
+          notifications,
+          getAnchorFromBrowser(this.tabbrowser.selectedBrowser)
+        )
+      );
+      return;
+    }
+
+    // Notifications are suppressed, ensure that the panel is hidden.
+    if (!this._suppress) {
+      this._suppress = true;
+      this._hidePanel().catch(console.error);
+    }
+  },
+
+  /**
+   * Removes one or many Notifications.
+   * @param {Notification|Notification[]} notification - The Notification object/s to remove.
+   * @param {Boolean} [isCancel] - Whether to signal,  in the notification event, that removal
+   *  should be treated as cancel. This is currently used to cancel permission requests
+   *  when their Notifications are removed.
+   */
+  remove: function PopupNotifications_remove(notification, isCancel = false) {
+    let notificationArray = Array.isArray(notification)
+      ? notification
+      : [notification];
+    let activeBrowser;
+
+    notificationArray.forEach(n => {
+      this._remove(n, isCancel);
+      if (!activeBrowser && this._isActiveBrowser(n.browser)) {
+        activeBrowser = n.browser;
+      }
+    });
+
+    if (activeBrowser) {
+      let browserNotifications =
+        this._getNotificationsForBrowser(activeBrowser);
+      this._update(browserNotifications);
+    }
+  },
+
+  handleEvent(aEvent) {
+    switch (aEvent.type) {
+      case "popuphidden":
+        this._onPopupHidden(aEvent);
+        break;
+      case "activate":
+      case "popuppositioned":
+        if (this.isPanelOpen) {
+          for (let elt of this.panel.children) {
+            elt.notification.timeShown = Math.max(
+              this.window.performance.now(),
+              elt.notification.timeShown ?? 0
+            );
+          }
+          break;
+        }
+      // fall through
+      case "TabSelect":
+        // setTimeout(..., 0) needed, otherwise openPopup from "activate" event
+        // handler results in the popup being hidden again for some reason...
+        this.window.setTimeout(() => {
+          this._suppress = this._shouldSuppress();
+          this._update();
+        }, 0);
+        break;
+      case "click":
+      case "keypress":
+        this._onIconBoxCommand(aEvent);
+        break;
+    }
+  },
+
+  // Utility methods
+
+  _ignoreDismissal: null,
+  _currentAnchorElement: null,
+
+  /**
+   * Gets notifications for the currently selected browser.
+   */
+  get _currentNotifications() {
+    return this.tabbrowser.selectedBrowser
+      ? this._getNotificationsForBrowser(this.tabbrowser.selectedBrowser)
+      : [];
+  },
+
+  _remove: function PopupNotifications_removeHelper(
+    notification,
+    isCancel = false
+  ) {
+    // This notification may already be removed, in which case let's just fail
+    // silently.
+    let notifications = this._getNotificationsForBrowser(notification.browser);
+    if (!notifications) {
+      return;
+    }
+
+    var index = notifications.indexOf(notification);
+    if (index == -1) {
+      return;
+    }
+
+    if (this._isActiveBrowser(notification.browser)) {
+      notification.anchorElement.removeAttribute(ICON_ATTRIBUTE_SHOWING);
+    }
+
+    // remove the notification
+    notifications.splice(index, 1);
+    this._fireCallback(
+      notification,
+      NOTIFICATION_EVENT_REMOVED,
+      this.nextRemovalReason,
+      isCancel
+    );
+  },
+
+  /**
+   * Dismisses the notification without removing it.
+   *
+   * @param {Event} the event associated with the user interaction that
+   *                caused the dismissal
+   * @param {boolean} whether to disable persistent status. Normally,
+   *                  persistent prompts can not be dismissed. You can
+   *                  use this argument to force dismissal.
+   */
+  _dismiss: function PopupNotifications_dismiss(
+    event,
+    disablePersistent = false
+  ) {
+    if (disablePersistent) {
+      let notificationEl = getNotificationFromElement(event.target);
+      if (notificationEl) {
+        notificationEl.notification.options.persistent = false;
+      }
+    }
+
+    let browser =
+      this.panel.firstElementChild &&
+      this.panel.firstElementChild.notification.browser;
+    this.panel.hidePopup();
+    if (browser) {
+      browser.focus();
+    }
+  },
+
+  /**
+   * Hides the notification popup.
+   */
+  _hidePanel: function PopupNotifications_hide() {
+    if (this.panel.state == "closed") {
+      return Promise.resolve();
+    }
+    if (this._ignoreDismissal) {
+      return this._ignoreDismissal.promise;
+    }
+    let deferred = PromiseUtils.defer();
+    this._ignoreDismissal = deferred;
+    this.panel.hidePopup();
+    return deferred.promise;
+  },
+
+  /**
+   * Removes all notifications from the notification popup.
+   */
+  _clearPanel() {
+    let popupnotification;
+    while ((popupnotification = this.panel.lastElementChild)) {
+      this.panel.removeChild(popupnotification);
+
+      // If this notification was provided by the chrome document rather than
+      // created ad hoc, move it back to where we got it from.
+      let originalParent = gNotificationParents.get(popupnotification);
+      if (originalParent) {
+        popupnotification.notification = null;
+
+        // Re-hide the notification such that it isn't rendered in the chrome
+        // document. _refreshPanel will unhide it again when needed.
+        popupnotification.hidden = true;
+
+        originalParent.appendChild(popupnotification);
+      }
+    }
+  },
+
+  /**
+   * Formats the notification description message before we display it
+   * and splits it into three parts if the message contains "<>" as
+   * placeholder.
+   *
+   * param notification
+   *       The Notification object which contains the message to format.
+   *
+   * @returns a Javascript object that has the following properties:
+   * start: A start label string containing the first part of the message.
+   *        It may contain the whole string if the description message
+   *        does not have "<>" as a placeholder. For example, local
+   *        file URIs with description messages that don't display hostnames.
+   * name:  A string that is formatted to look bold. It replaces the
+   *        placeholder with the options.name property from the notification
+   *        object which is usually an addon name or a host name.
+   * end:   The last part of the description message.
+   */
+  _formatDescriptionMessage(n) {
+    let text = {};
+    let array = n.message.split(/<>|{}/);
+    text.start = array[0] || "";
+    text.name = n.options.name || "";
+    text.end = array[1] || "";
+    if (array.length == 3) {
+      text.secondName = n.options.secondName || "";
+      text.secondEnd = array[2] || "";
+
+      // name and secondName should be in logical positions.  Swap them in case
+      // the second placeholder came before the first one in the original string.
+      if (n.message.indexOf("{}") < n.message.indexOf("<>")) {
+        let tmp = text.name;
+        text.name = text.secondName;
+        text.secondName = tmp;
+      }
+    } else if (array.length > 3) {
+      console.error(
+        "Unexpected array length encountered in " +
+          "_formatDescriptionMessage: ",
+        array.length
+      );
+    }
+    return text;
+  },
+
+  _refreshPanel: function PopupNotifications_refreshPanel(notificationsToShow) {
+    this._clearPanel();
+
+    notificationsToShow.forEach(function (n) {
+      let doc = this.window.document;
+
+      // Append "-notification" to the ID to try to avoid ID conflicts with other stuff
+      // in the document.
+      let popupnotificationID = n.id + "-notification";
+
+      // If the chrome document provides a popupnotification with this id, use
+      // that. Otherwise create it ad-hoc.
+      let popupnotification = doc.getElementById(popupnotificationID);
+      if (popupnotification) {
+        gNotificationParents.set(
+          popupnotification,
+          popupnotification.parentNode
+        );
+      } else {
+        popupnotification = doc.createXULElement("popupnotification");
+      }
+
+      // Create the notification description element.
+      let desc = this._formatDescriptionMessage(n);
+      popupnotification.setAttribute("label", desc.start);
+      popupnotification.setAttribute("name", desc.name);
+      popupnotification.setAttribute("endlabel", desc.end);
+      if ("secondName" in desc && "secondEnd" in desc) {
+        popupnotification.setAttribute("secondname", desc.secondName);
+        popupnotification.setAttribute("secondendlabel", desc.secondEnd);
+      } else {
+        popupnotification.removeAttribute("secondname");
+        popupnotification.removeAttribute("secondendlabel");
+      }
+
+      if (n.options.hintText) {
+        popupnotification.setAttribute("hinttext", n.options.hintText);
+      } else {
+        popupnotification.removeAttribute("hinttext");
+      }
+
+      popupnotification.setAttribute("id", popupnotificationID);
+      popupnotification.setAttribute("popupid", n.id);
+      popupnotification.setAttribute(
+        "oncommand",
+        "PopupNotifications._onCommand(event);"
+      );
+      popupnotification.setAttribute(
+        "closebuttoncommand",
+        `PopupNotifications._dismiss(event, true);`
+      );
+
+      popupnotification.toggleAttribute(
+        "hasicon",
+        !!(n.options.popupIconURL || n.options.popupIconClass)
+      );
+
+      if (n.mainAction) {
+        popupnotification.setAttribute("buttonlabel", n.mainAction.label);
+        popupnotification.setAttribute(
+          "buttonaccesskey",
+          n.mainAction.accessKey
+        );
+        popupnotification.setAttribute(
+          "buttoncommand",
+          "PopupNotifications._onButtonEvent(event, 'buttoncommand');"
+        );
+        popupnotification.setAttribute(
+          "dropmarkerpopupshown",
+          "PopupNotifications._onButtonEvent(event, 'dropmarkerpopupshown');"
+        );
+        popupnotification.setAttribute(
+          "learnmoreclick",
+          "PopupNotifications._onButtonEvent(event, 'learnmoreclick');"
+        );
+        popupnotification.setAttribute(
+          "menucommand",
+          "PopupNotifications._onMenuCommand(event);"
+        );
+      } else {
+        // Enable the default button to let the user close the popup if the close button is hidden
+        popupnotification.setAttribute(
+          "buttoncommand",
+          "PopupNotifications._onButtonEvent(event, 'buttoncommand');"
+        );
+        popupnotification.toggleAttribute("buttonhighlight", true);
+        popupnotification.removeAttribute("buttonlabel");
+        popupnotification.removeAttribute("buttonaccesskey");
+        popupnotification.removeAttribute("dropmarkerpopupshown");
+        popupnotification.removeAttribute("learnmoreclick");
+        popupnotification.removeAttribute("menucommand");
+      }
+
+      let classes = "popup-notification-icon";
+      if (n.options.popupIconClass) {
+        classes += " " + n.options.popupIconClass;
+      }
+      popupnotification.setAttribute("iconclass", classes);
+
+      if (n.options.popupIconURL) {
+        popupnotification.setAttribute("icon", n.options.popupIconURL);
+      } else {
+        popupnotification.removeAttribute("icon");
+      }
+
+      if (n.options.learnMoreURL) {
+        popupnotification.setAttribute("learnmoreurl", n.options.learnMoreURL);
+      } else {
+        popupnotification.removeAttribute("learnmoreurl");
+      }
+
+      if (n.options.displayURI) {
+        let uri;
+        try {
+          if (n.options.displayURI instanceof Ci.nsIFileURL) {
+            uri = n.options.displayURI.pathQueryRef;
+          } else {
+            try {
+              uri = n.options.displayURI.hostPort;
+            } catch (e) {
+              uri = n.options.displayURI.spec;
+            }
+          }
+          popupnotification.setAttribute("origin", uri);
+        } catch (e) {
+          console.error(e);
+          popupnotification.removeAttribute("origin");
+        }
+      } else {
+        popupnotification.removeAttribute("origin");
+      }
+
+      if (n.options.hideClose) {
+        popupnotification.setAttribute("closebuttonhidden", "true");
+      }
+
+      popupnotification.notification = n;
+      let menuitems = [];
+
+      if (n.mainAction && n.secondaryActions && n.secondaryActions.length) {
+        let telemetryStatId = TELEMETRY_STAT_ACTION_2;
+
+        let secondaryAction = n.secondaryActions[0];
+        popupnotification.setAttribute(
+          "secondarybuttonlabel",
+          secondaryAction.label
+        );
+        popupnotification.setAttribute(
+          "secondarybuttonaccesskey",
+          secondaryAction.accessKey
+        );
+        popupnotification.setAttribute(
+          "secondarybuttoncommand",
+          "PopupNotifications._onButtonEvent(event, 'secondarybuttoncommand');"
+        );
+
+        for (let i = 1; i < n.secondaryActions.length; i++) {
+          let action = n.secondaryActions[i];
+          let item = doc.createXULElement("menuitem");
+          item.setAttribute("label", action.label);
+          item.setAttribute("accesskey", action.accessKey);
+          item.notification = n;
+          item.action = action;
+
+          menuitems.push(item);
+
+          // We can only record a limited number of actions in telemetry. If
+          // there are more, the latest are all recorded in the last bucket.
+          item.action.telemetryStatId = telemetryStatId;
+          if (telemetryStatId < TELEMETRY_STAT_ACTION_LAST) {
+            telemetryStatId++;
+          }
+        }
+        popupnotification.setAttribute("secondarybuttonhidden", "false");
+      } else {
+        popupnotification.setAttribute("secondarybuttonhidden", "true");
+      }
+      popupnotification.setAttribute(
+        "dropmarkerhidden",
+        n.secondaryActions.length < 2 ? "true" : "false"
+      );
+
+      let checkbox = n.options.checkbox;
+      if (checkbox && checkbox.label) {
+        let checked =
+          n._checkboxChecked != null ? n._checkboxChecked : !!checkbox.checked;
+        popupnotification.checkboxState = {
+          checked,
+          label: checkbox.label,
+        };
+
+        if (checked) {
+          this._setNotificationUIState(
+            popupnotification,
+            checkbox.checkedState
+          );
+        } else {
+          this._setNotificationUIState(
+            popupnotification,
+            checkbox.uncheckedState
+          );
+        }
+      } else {
+        popupnotification.checkboxState = null;
+        // Reset the UI state to avoid previous state bleeding into this prompt.
+        this._setNotificationUIState(popupnotification);
+      }
+
+      this.panel.appendChild(popupnotification);
+
+      // The popupnotification may be hidden if we got it from the chrome
+      // document rather than creating it ad hoc.
+      popupnotification.show();
+
+      popupnotification.menupopup.textContent = "";
+      popupnotification.menupopup.append(...menuitems);
+    }, this);
+  },
+
+  _setNotificationUIState(notification, state = {}) {
+    let mainAction = notification.notification.mainAction;
+    if (
+      (mainAction && mainAction.disabled) ||
+      state.disableMainAction ||
+      notification.hasAttribute("invalidselection")
+    ) {
+      notification.setAttribute("mainactiondisabled", "true");
+    } else {
+      notification.removeAttribute("mainactiondisabled");
+    }
+    if (state.warningLabel) {
+      notification.setAttribute("warninglabel", state.warningLabel);
+      notification.removeAttribute("warninghidden");
+    } else {
+      notification.setAttribute("warninghidden", "true");
+    }
+  },
+
+  _extendSecurityDelay(notifications) {
+    let now = this.window.performance.now();
+    notifications.forEach(n => {
+      n.timeShown = now + FULLSCREEN_TRANSITION_TIME_SHOWN_OFFSET_MS;
+    });
+  },
+
+  _showPanel: function PopupNotifications_showPanel(
+    notificationsToShow,
+    anchorElement
+  ) {
+    this.panel.hidden = false;
+
+    notificationsToShow = notificationsToShow.filter(n => {
+      if (anchorElement != n.anchorElement) {
+        return false;
+      }
+
+      let dismiss = this._fireCallback(n, NOTIFICATION_EVENT_SHOWING);
+      if (dismiss) {
+        n.dismissed = true;
+      }
+      return !dismiss;
+    });
+    if (!notificationsToShow.length) {
+      return;
+    }
+
+    let notificationIds = notificationsToShow.map(n => n.id);
+
+    this._refreshPanel(notificationsToShow);
+
+    // The element the PopupNotification should anchor to might not be visible.
+    // Check its visibility using a callback that returns the same anchor
+    // element if its visible, or a fallback option that is visible.
+    // If no fallbacks are visible, it should return null.
+    if (this._getVisibleAnchorElement) {
+      anchorElement = this._getVisibleAnchorElement(anchorElement);
+    }
+    // In case _getVisibleAnchorElement provided a non-visible element.
+    if (!anchorElement?.checkVisibility()) {
+      // We only ever show notifications for the current browser,
+      // so we can just use the current tab.
+      anchorElement = this.tabbrowser.selectedTab;
+      if (!anchorElement?.checkVisibility()) {
+        // If we're in an entirely chromeless environment, set the anchorElement
+        // to null and let openPopup show the notification at (0,0) later.
+        anchorElement = null;
+      }
+    }
+
+    // Remember the time the notification was shown for the security delay.
+    notificationsToShow.forEach(
+      n =>
+        (n.timeShown = Math.max(
+          this.window.performance.now(),
+          n.timeShown ?? 0
+        ))
+    );
+
+    if (this.isPanelOpen && this._currentAnchorElement == anchorElement) {
+      notificationsToShow.forEach(function (n) {
+        this._fireCallback(n, NOTIFICATION_EVENT_SHOWN);
+      }, this);
+
+      // Make sure we update the noautohide attribute on the panel, in case it changed.
+      if (notificationsToShow.some(n => n.options.persistent)) {
+        this.panel.setAttribute("noautohide", "true");
+      } else {
+        this.panel.removeAttribute("noautohide");
+      }
+
+      // Let tests know that the panel was updated and what notifications it was
+      // updated with so that tests can wait for the correct notifications to be
+      // added.
+      let event = new this.window.CustomEvent("PanelUpdated", {
+        detail: notificationIds,
+      });
+      this.panel.dispatchEvent(event);
+      return;
+    }
+
+    // If the panel is already open but we're changing anchors, we need to hide
+    // it first.  Otherwise it can appear in the wrong spot.  (_hidePanel is
+    // safe to call even if the panel is already hidden.)
+    this._hidePanel().then(() => {
+      this._currentAnchorElement = anchorElement;
+
+      if (notificationsToShow.some(n => n.options.persistent)) {
+        this.panel.setAttribute("noautohide", "true");
+      } else {
+        this.panel.removeAttribute("noautohide");
+      }
+
+      notificationsToShow.forEach(function (n) {
+        // Record that the notification was actually displayed on screen.
+        // Notifications that were opened a second time or that were originally
+        // shown with "options.dismissed" will be recorded in a separate bucket.
+        n._recordTelemetryStat(TELEMETRY_STAT_OFFERED);
+      }, this);
+
+      // We're about to open the panel while in a full screen transition. Extend
+      // the security delay.
+      if (this.window.isInFullScreenTransition) {
+        this._extendSecurityDelay(notificationsToShow);
+      }
+
+      let target = this.panel;
+      if (target.parentNode) {
+        // NOTIFICATION_EVENT_SHOWN should be fired for the panel before
+        // anyone listening for popupshown on the panel gets run. Otherwise,
+        // the panel will not be initialized when the popupshown event
+        // listeners run.
+        // By targeting the panel's parent and using a capturing listener, we
+        // can have our listener called before others waiting for the panel to
+        // be shown (which probably expect the panel to be fully initialized)
+        target = target.parentNode;
+      }
+      if (this._popupshownListener) {
+        target.removeEventListener(
+          "popupshown",
+          this._popupshownListener,
+          true
+        );
+      }
+      this._popupshownListener = function (e) {
+        target.removeEventListener(
+          "popupshown",
+          this._popupshownListener,
+          true
+        );
+        this._popupshownListener = null;
+
+        notificationsToShow.forEach(function (n) {
+          this._fireCallback(n, NOTIFICATION_EVENT_SHOWN);
+        }, this);
+        // These notifications are used by tests to know when all the processing
+        // required to display the panel has happened.
+        this.panel.dispatchEvent(new this.window.CustomEvent("Shown"));
+        let event = new this.window.CustomEvent("PanelUpdated", {
+          detail: notificationIds,
+        });
+        this.panel.dispatchEvent(event);
+      };
+      this._popupshownListener = this._popupshownListener.bind(this);
+      target.addEventListener("popupshown", this._popupshownListener, true);
+
+      let popupOptions = notificationsToShow.findLast(
+        n => n.options?.popupOptions
+      )?.options?.popupOptions;
+      if (popupOptions) {
+        this.panel.openPopup(anchorElement, popupOptions);
+      } else {
+        this.panel.openPopup(anchorElement, "bottomleft topleft", 0, 0);
+      }
+    });
+  },
+
+  /**
+   * Updates the notification state in response to window activation or tab
+   * selection changes.
+   *
+   * @param notifications an array of Notification instances. if null,
+   *                      notifications will be retrieved off the current
+   *                      browser tab
+   * @param anchors       is a XUL element or a Set of XUL elements that the
+   *                      notifications panel(s) will be anchored to.
+   * @param dismissShowing if true, dismiss any currently visible notifications
+   *                       if there are no notifications to show. Otherwise,
+   *                       currently displayed notifications will be left alone.
+   */
+  _update: function PopupNotifications_update(
+    notifications,
+    anchors = new Set(),
+    dismissShowing = false
+  ) {
+    if (ChromeUtils.getClassName(anchors) == "XULElement") {
+      anchors = new Set([anchors]);
+    }
+
+    if (!notifications) {
+      notifications = this._currentNotifications;
+    }
+
+    let haveNotifications = !!notifications.length;
+    if (!anchors.size && haveNotifications) {
+      anchors = this._getAnchorsForNotifications(notifications);
+    }
+
+    let useIconBox = !!this.iconBox;
+    if (useIconBox && anchors.size) {
+      for (let anchor of anchors) {
+        if (anchor.parentNode == this.iconBox) {
+          continue;
+        }
+        useIconBox = false;
+        break;
+      }
+    }
+
+    // Filter out notifications that have been dismissed, unless they are
+    // persistent. Also check if we should not show any notification.
+    let notificationsToShow = [];
+    if (!this._suppress) {
+      notificationsToShow = notifications.filter(
+        n => (!n.dismissed || n.options.persistent) && !n.options.neverShow
+      );
+    }
+
+    if (useIconBox) {
+      // Hide icons of the previous tab.
+      this._hideIcons();
+    }
+
+    if (haveNotifications) {
+      // Also filter out notifications that are for a different anchor.
+      notificationsToShow = notificationsToShow.filter(function (n) {
+        return anchors.has(n.anchorElement);
+      });
+
+      if (useIconBox) {
+        this._showIcons(notifications);
+        this.iconBox.hidden = false;
+        // Make sure that panels can only be attached to anchors of shown
+        // notifications inside an iconBox.
+        anchors = this._getAnchorsForNotifications(notificationsToShow);
+      } else if (anchors.size) {
+        this._updateAnchorIcons(notifications, anchors);
+      }
+    }
+
+    if (notificationsToShow.length) {
+      let anchorElement = anchors.values().next().value;
+      if (anchorElement) {
+        this._showPanel(notificationsToShow, anchorElement);
+      }
+
+      // Setup a capturing event listener on the whole window to catch the
+      // escape key while persistent notifications are visible.
+      this.window.addEventListener(
+        "keypress",
+        this._handleWindowKeyPress,
+        true
+      );
+    } else {
+      // Notify observers that we're not showing the popup (useful for testing)
+      this._notify("updateNotShowing");
+
+      // Close the panel if there are no notifications to show.
+      // When called from PopupNotifications.show() we should never close the
+      // panel, however. It may just be adding a dismissed notification, in
+      // which case we want to continue showing any existing notifications.
+      if (!dismissShowing) {
+        this._dismiss();
+      }
+
+      // Only hide the iconBox if we actually have no notifications (as opposed
+      // to not having any showable notifications)
+      if (!haveNotifications) {
+        if (useIconBox) {
+          this.iconBox.hidden = true;
+        } else if (anchors.size) {
+          for (let anchorElement of anchors) {
+            anchorElement.removeAttribute(ICON_ATTRIBUTE_SHOWING);
+          }
+        }
+      }
+
+      // Stop listening to keyboard events for notifications.
+      this.window.removeEventListener(
+        "keypress",
+        this._handleWindowKeyPress,
+        true
+      );
+    }
+  },
+
+  _updateAnchorIcons: function PopupNotifications_updateAnchorIcons(
+    notifications,
+    anchorElements
+  ) {
+    for (let anchorElement of anchorElements) {
+      anchorElement.setAttribute(ICON_ATTRIBUTE_SHOWING, "true");
+    }
+  },
+
+  _showIcons: function PopupNotifications_showIcons(aCurrentNotifications) {
+    for (let notification of aCurrentNotifications) {
+      let anchorElm = notification.anchorElement;
+      if (anchorElm) {
+        anchorElm.setAttribute(ICON_ATTRIBUTE_SHOWING, "true");
+
+        if (notification.options.extraAttr) {
+          anchorElm.setAttribute("extraAttr", notification.options.extraAttr);
+        } else {
+          anchorElm.removeAttribute("extraAttr");
+        }
+      }
+    }
+  },
+
+  _hideIcons: function PopupNotifications_hideIcons() {
+    let icons = this.iconBox.querySelectorAll(ICON_SELECTOR);
+    for (let icon of icons) {
+      icon.removeAttribute(ICON_ATTRIBUTE_SHOWING);
+    }
+  },
+
+  /**
+   * Gets and sets notifications for the browser.
+   */
+  _getNotificationsForBrowser: function PopupNotifications_getNotifications(
+    browser
+  ) {
+    let notifications = popupNotificationsMap.get(browser);
+    if (!notifications) {
+      // Initialize the WeakMap for the browser so callers can reference/manipulate the array.
+      notifications = [];
+      popupNotificationsMap.set(browser, notifications);
+    }
+    return notifications;
+  },
+  _setNotificationsForBrowser: function PopupNotifications_setNotifications(
+    browser,
+    notifications
+  ) {
+    popupNotificationsMap.set(browser, notifications);
+    return notifications;
+  },
+
+  _getAnchorsForNotifications:
+    function PopupNotifications_getAnchorsForNotifications(
+      notifications,
+      defaultAnchor
+    ) {
+      let anchors = new Set();
+      for (let notification of notifications) {
+        if (notification.anchorElement) {
+          anchors.add(notification.anchorElement);
+        }
+      }
+      if (defaultAnchor && !anchors.size) {
+        anchors.add(defaultAnchor);
+      }
+      return anchors;
+    },
+
+  _isActiveBrowser(browser) {
+    // We compare on frameLoader instead of just comparing the
+    // selectedBrowser and browser directly because browser tabs in
+    // Responsive Design Mode put the actual web content into a
+    // mozbrowser iframe and proxy property read/write and method
+    // calls from the tab to that iframe. This is so that attempts
+    // to reload the tab end up reloading the content in
+    // Responsive Design Mode, and not the Responsive Design Mode
+    // viewer itself.
+    //
+    // This means that PopupNotifications can come up from a browser
+    // in Responsive Design Mode, but the selectedBrowser will not match
+    // the browser being passed into this function, despite the browser
+    // actually being within the selected tab. We workaround this by
+    // comparing frameLoader instead, which is proxied from the outer
+    // <xul:browser> to the inner mozbrowser <iframe>.
+    return this.tabbrowser.selectedBrowser.frameLoader == browser.frameLoader;
+  },
+
+  _onIconBoxCommand: function PopupNotifications_onIconBoxCommand(event) {
+    // Left click, space or enter only
+    let type = event.type;
+    if (type == "click" && event.button != 0) {
+      return;
+    }
+
+    if (
+      type == "keypress" &&
+      !(
+        event.charCode == event.DOM_VK_SPACE ||
+        event.keyCode == event.DOM_VK_RETURN
+      )
+    ) {
+      return;
+    }
+
+    if (!this._currentNotifications.length) {
+      return;
+    }
+
+    event.stopPropagation();
+
+    // Get the anchor that is the immediate child of the icon box
+    let anchor = event.target;
+    while (anchor && anchor.parentNode != this.iconBox) {
+      anchor = anchor.parentNode;
+    }
+
+    if (!anchor) {
+      return;
+    }
+
+    // If the panel is not closed, and the anchor is different, immediately mark all
+    // active notifications for the previous anchor as dismissed
+    if (this.panel.state != "closed" && anchor != this._currentAnchorElement) {
+      this._dismissOrRemoveCurrentNotifications();
+    }
+
+    // Avoid reshowing notifications that are already shown and have not been dismissed.
+    if (this.panel.state == "closed" || anchor != this._currentAnchorElement) {
+      // As soon as the panel is shown, focus the first element in the selected notification.
+      this.panel.addEventListener(
+        "popupshown",
+        () =>
+          this.window.document.commandDispatcher.advanceFocusIntoSubtree(
+            this.panel
+          ),
+        { once: true }
+      );
+
+      this._reshowNotifications(anchor);
+    } else {
+      // Focus the first element in the selected notification.
+      this.window.document.commandDispatcher.advanceFocusIntoSubtree(
+        this.panel
+      );
+    }
+  },
+
+  _reshowNotifications: function PopupNotifications_reshowNotifications(
+    anchor,
+    browser
+  ) {
+    // Mark notifications anchored to this anchor as un-dismissed
+    browser = browser || this.tabbrowser.selectedBrowser;
+    let notifications = this._getNotificationsForBrowser(browser);
+    notifications.forEach(function (n) {
+      if (n.anchorElement == anchor) {
+        n.dismissed = false;
+      }
+    });
+
+    if (this._isActiveBrowser(browser)) {
+      // ...and then show them.
+      this._update(notifications, anchor);
+    }
+  },
+
+  _swapBrowserNotifications:
+    function PopupNotifications_swapBrowserNoficications(
+      ourBrowser,
+      otherBrowser
+    ) {
+      // When swaping browser docshells (e.g. dragging tab to new window) we need
+      // to update our notification map.
+
+      let ourNotifications = this._getNotificationsForBrowser(ourBrowser);
+      let other = otherBrowser.ownerGlobal.PopupNotifications;
+      if (!other) {
+        if (ourNotifications.length) {
+          console.error(
+            "unable to swap notifications: otherBrowser doesn't support notifications"
+          );
+        }
+        return;
+      }
+      let otherNotifications = other._getNotificationsForBrowser(otherBrowser);
+      if (ourNotifications.length < 1 && otherNotifications.length < 1) {
+        // No notification to swap.
+        return;
+      }
+
+      otherNotifications = otherNotifications.filter(n => {
+        if (this._fireCallback(n, NOTIFICATION_EVENT_SWAPPING, ourBrowser)) {
+          n.browser = ourBrowser;
+          n.owner = this;
+          return true;
+        }
+        other._fireCallback(
+          n,
+          NOTIFICATION_EVENT_REMOVED,
+          this.nextRemovalReason
+        );
+        return false;
+      });
+
+      ourNotifications = ourNotifications.filter(n => {
+        if (this._fireCallback(n, NOTIFICATION_EVENT_SWAPPING, otherBrowser)) {
+          n.browser = otherBrowser;
+          n.owner = other;
+          return true;
+        }
+        this._fireCallback(
+          n,
+          NOTIFICATION_EVENT_REMOVED,
+          this.nextRemovalReason
+        );
+        return false;
+      });
+
+      this._setNotificationsForBrowser(otherBrowser, ourNotifications);
+      other._setNotificationsForBrowser(ourBrowser, otherNotifications);
+
+      if (otherNotifications.length) {
+        this._update(otherNotifications);
+      }
+      if (ourNotifications.length) {
+        other._update(ourNotifications);
+      }
+    },
+
+  _fireCallback: function PopupNotifications_fireCallback(n, event, ...args) {
+    try {
+      if (n.options.eventCallback) {
+        return n.options.eventCallback.call(n, event, ...args);
+      }
+    } catch (error) {
+      console.error(error);
+    }
+    return undefined;
+  },
+
+  _onPopupHidden: function PopupNotifications_onPopupHidden(event) {
+    if (event.target != this.panel) {
+      return;
+    }
+
+    // It's possible that a popupnotification set `aria-describedby` on the
+    // panel element in its eventCallback function. If so, we'll clear that out
+    // before showing the next notification.
+    this.panel.removeAttribute("aria-describedby");
+
+    // We may have removed the "noautofocus" attribute before showing the panel
+    // if the notification specified it wants to autofocus on first show.
+    // When the panel is closed, we have to restore the attribute to its default
+    // value, so we don't autofocus it if it's subsequently opened from a different code path.
+    this.panel.setAttribute("noautofocus", "true");
+
+    // Handle the case where the panel was closed programmatically.
+    if (this._ignoreDismissal) {
+      this._ignoreDismissal.resolve();
+      this._ignoreDismissal = null;
+      return;
+    }
+
+    this._dismissOrRemoveCurrentNotifications();
+
+    this._clearPanel();
+
+    this._update();
+  },
+
+  _dismissOrRemoveCurrentNotifications() {
+    let browser =
+      this.panel.firstElementChild &&
+      this.panel.firstElementChild.notification.browser;
+    if (!browser) {
+      return;
+    }
+
+    let notifications = this._getNotificationsForBrowser(browser);
+    // Mark notifications as dismissed and call dismissal callbacks
+    for (let nEl of this.panel.children) {
+      let notificationObj = nEl.notification;
+      // Never call a dismissal handler on a notification that's been removed.
+      if (!notifications.includes(notificationObj)) {
+        return;
+      }
+
+      // Record the time of the first notification dismissal if the main action
+      // was not triggered in the meantime.
+      let timeSinceShown =
+        this.window.performance.now() - notificationObj.timeShown;
+      if (
+        !notificationObj.wasDismissed &&
+        !notificationObj.recordedTelemetryMainAction
+      ) {
+        notificationObj._recordTelemetry(
+          "POPUP_NOTIFICATION_DISMISSAL_MS",
+          timeSinceShown
+        );
+      }
+
+      // Do not mark the notification as dismissed or fire NOTIFICATION_EVENT_DISMISSED
+      // if the notification is removed.
+      if (notificationObj.options.removeOnDismissal) {
+        notificationObj._recordTelemetryStat(this.nextRemovalReason);
+        this._remove(notificationObj);
+      } else {
+        notificationObj.dismissed = true;
+        this._fireCallback(notificationObj, NOTIFICATION_EVENT_DISMISSED);
+      }
+    }
+  },
+
+  _onCheckboxCommand(event) {
+    let notificationEl = getNotificationFromElement(event.originalTarget);
+    let checked = notificationEl.checkbox.checked;
+    let notification = notificationEl.notification;
+
+    // Save checkbox state to be able to persist it when re-opening the doorhanger.
+    notification._checkboxChecked = checked;
+
+    if (checked) {
+      this._setNotificationUIState(
+        notificationEl,
+        notification.options.checkbox.checkedState
+      );
+    } else {
+      this._setNotificationUIState(
+        notificationEl,
+        notification.options.checkbox.uncheckedState
+      );
+    }
+    event.stopPropagation();
+  },
+
+  _onCommand(event) {
+    // Ignore events from buttons as they are submitting and so don't need checks
+    if (event.originalTarget.localName == "button") {
+      return;
+    }
+    let notificationEl = getNotificationFromElement(event.target);
+
+    let notification = notificationEl.notification;
+    if (!notification.options.checkbox) {
+      this._setNotificationUIState(notificationEl);
+      return;
+    }
+
+    if (notificationEl.checkbox.checked) {
+      this._setNotificationUIState(
+        notificationEl,
+        notification.options.checkbox.checkedState
+      );
+    } else {
+      this._setNotificationUIState(
+        notificationEl,
+        notification.options.checkbox.uncheckedState
+      );
+    }
+  },
+
+  _onButtonEvent(event, type, source = "button", notificationEl = null) {
+    if (!notificationEl) {
+      notificationEl = getNotificationFromElement(event.originalTarget);
+    }
+
+    if (!notificationEl) {
+      throw new Error(
+        "PopupNotifications._onButtonEvent: couldn't find notification element"
+      );
+    }
+
+    if (!notificationEl.notification) {
+      throw new Error(
+        "PopupNotifications._onButtonEvent: couldn't find notification"
+      );
+    }
+
+    let notification = notificationEl.notification;
+
+    // Receiving a button event means the notification should have been shown.
+    // Make sure that timeShown is always set to ensure we don't break the
+    // security delay calculation below.
+    if (!notification.timeShown) {
+      console.warn(
+        "_onButtonEvent: notification.timeShown is unset. Setting to now.",
+        notification
+      );
+      notification.timeShown = this.window.performance.now();
+    }
+
+    if (type == "dropmarkerpopupshown") {
+      notification._recordTelemetryStat(TELEMETRY_STAT_OPEN_SUBMENU);
+      return;
+    }
+
+    if (type == "learnmoreclick") {
+      notification._recordTelemetryStat(TELEMETRY_STAT_LEARN_MORE);
+      return;
+    }
+
+    if (type == "buttoncommand") {
+      // Record the total timing of the main action since the notification was
+      // created, even if the notification was dismissed in the meantime.
+      let timeSinceCreated =
+        this.window.performance.now() - notification.timeCreated;
+      if (!notification.recordedTelemetryMainAction) {
+        notification.recordedTelemetryMainAction = true;
+        notification._recordTelemetry(
+          "POPUP_NOTIFICATION_MAIN_ACTION_MS",
+          timeSinceCreated
+        );
+      }
+    }
+
+    if (type == "buttoncommand" || type == "secondarybuttoncommand") {
+      if (Services.focus.activeWindow != this.window) {
+        Services.console.logStringMessage(
+          "PopupNotifications._onButtonEvent: " +
+            "Button click happened before the window was focused"
+        );
+        this.window.focus();
+        return;
+      }
+
+      let now = this.window.performance.now();
+      let timeSinceShown = now - notification.timeShown;
+      if (timeSinceShown < lazy.buttonDelay) {
+        Services.console.logStringMessage(
+          "PopupNotifications._onButtonEvent: " +
+            "Button click happened before the security delay: " +
+            timeSinceShown +
+            "ms"
+        );
+        notification.timeShown = Math.max(now, notification.timeShown);
+        return;
+      }
+    }
+
+    let action = notification.mainAction;
+    let telemetryStatId = TELEMETRY_STAT_ACTION_1;
+
+    if (type == "secondarybuttoncommand") {
+      action = notification.secondaryActions[0];
+      telemetryStatId = TELEMETRY_STAT_ACTION_2;
+    }
+
+    notification._recordTelemetryStat(telemetryStatId);
+
+    if (action) {
+      try {
+        action.callback.call(undefined, {
+          checkboxChecked: notificationEl.checkbox.checked,
+          source,
+          event,
+        });
+      } catch (error) {
+        console.error(error);
+      }
+
+      if (action.dismiss) {
+        this._dismiss();
+        return;
+      }
+    }
+
+    this._remove(notification);
+    this._update();
+  },
+
+  _onMenuCommand: function PopupNotifications_onMenuCommand(event) {
+    let target = event.originalTarget;
+    if (!target.action || !target.notification) {
+      throw new Error(
+        "menucommand target has no associated action/notification"
+      );
+    }
+
+    let notificationEl = getNotificationFromElement(target);
+    event.stopPropagation();
+
+    target.notification._recordTelemetryStat(target.action.telemetryStatId);
+
+    try {
+      target.action.callback.call(undefined, {
+        checkboxChecked: notificationEl.checkbox.checked,
+        source: "menucommand",
+      });
+    } catch (error) {
+      console.error(error);
+    }
+
+    if (target.action.dismiss) {
+      this._dismiss();
+      return;
+    }
+
+    this._remove(target.notification);
+    this._update();
+  },
+
+  _notify: function PopupNotifications_notify(topic) {
+    Services.obs.notifyObservers(null, "PopupNotifications-" + topic);
+  },
+};