--- a/browser/actors/ClickHandlerChild.jsm
+++ b/browser/actors/ClickHandlerChild.jsm
@@ -1,18 +1,15 @@
 /* -*- indent-tabs-mode: nil; js-indent-level: 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 EXPORTED_SYMBOLS = ["ClickHandlerChild"];
 
-const { ActorChild } = ChromeUtils.import(
-  "resource://gre/modules/ActorChild.jsm"
-);
 const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
 
 ChromeUtils.defineModuleGetter(
   this,
   "BrowserUtils",
   "resource://gre/modules/BrowserUtils.jsm"
 );
 ChromeUtils.defineModuleGetter(
@@ -26,17 +23,17 @@ ChromeUtils.defineModuleGetter(
   "resource://gre/modules/WebNavigationFrames.jsm"
 );
 ChromeUtils.defineModuleGetter(
   this,
   "E10SUtils",
   "resource://gre/modules/E10SUtils.jsm"
 );
 
-class ClickHandlerChild extends ActorChild {
+class ClickHandlerChild extends JSWindowActorChild {
   handleEvent(event) {
     if (
       !event.isTrusted ||
       event.defaultPrevented ||
       event.button == 2 ||
       (event.type == "click" && event.button == 1)
     ) {
       return;
@@ -117,17 +114,17 @@ class ClickHandlerChild extends ActorChi
         json.title = node.getAttribute("title");
       }
 
       // Check if the link needs to be opened with mixed content allowed.
       // Only when the owner doc has |mixedContentChannel| and the same origin
       // should we allow mixed content.
       json.allowMixedContent = false;
       let docshell = ownerDoc.defaultView.docShell;
-      if (this.mm.docShell.mixedContentChannel) {
+      if (this.docShell.mixedContentChannel) {
         const sm = Services.scriptSecurityManager;
         try {
           let targetURI = Services.io.newURI(href);
           let isPrivateWin =
             ownerDoc.nodePrincipal.originAttributes.privateBrowsingId > 0;
           sm.checkSameOriginURI(
             docshell.mixedContentChannel.URI,
             targetURI,
@@ -146,39 +143,39 @@ class ClickHandlerChild extends ActorChi
       // when it's clicked with middle button, we should prevent multiple
       // actions here to avoid leaking clipboard content unexpectedly.
       // Note that whether the link will work actually or not does not matter
       // because in this case, user does not intent to paste clipboard content.
       if (event.button === 1) {
         event.preventMultipleActions();
       }
 
-      this.mm.sendAsyncMessage("Content:Click", json);
+      this.sendAsyncMessage("Content:Click", json);
       return;
     }
 
     // This might be middle mouse navigation.
     if (event.button == 1) {
-      this.mm.sendAsyncMessage("Content:Click", json);
+      this.sendAsyncMessage("Content:Click", json);
     }
   }
 
   /**
    * Extracts linkNode and href for the current click target.
    *
    * @param event
    *        The click event.
    * @return [href, linkNode, linkPrincipal].
    *
    * @note linkNode will be null if the click wasn't on an anchor
    *       element. This includes SVG links, because callers expect |node|
    *       to behave like an <a> element, which SVG links (XLink) don't.
    */
   _hrefAndLinkNodeForClickEvent(event) {
-    let { content } = this.mm;
+    let content = this.contentWindow;
     function isHTMLLink(aNode) {
       // Be consistent with what nsContextMenu.js does.
       return (
         (aNode instanceof content.HTMLAnchorElement && aNode.href) ||
         (aNode instanceof content.HTMLAreaElement && aNode.href) ||
         aNode instanceof content.HTMLLinkElement
       );
     }

rename from browser/modules/ContentClick.jsm
rename to browser/actors/ClickHandlerParent.jsm
--- a/browser/modules/ContentClick.jsm
+++ b/browser/actors/ClickHandlerParent.jsm
@@ -1,16 +1,16 @@
 /* -*- mode: js; indent-tabs-mode: nil; js-indent-level: 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";
 
-var EXPORTED_SYMBOLS = ["ContentClick"];
+var EXPORTED_SYMBOLS = ["ClickHandlerParent"];
 
 const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
 
 ChromeUtils.defineModuleGetter(
   this,
   "PlacesUIUtils",
   "resource:///modules/PlacesUIUtils.jsm"
 );
@@ -20,44 +20,58 @@ ChromeUtils.defineModuleGetter(
   "resource://gre/modules/PrivateBrowsingUtils.jsm"
 );
 ChromeUtils.defineModuleGetter(
   this,
   "E10SUtils",
   "resource://gre/modules/E10SUtils.jsm"
 );
 
-var ContentClick = {
-  // Listeners are added in BrowserGlue.jsm
+let gContentClickListeners = new Set();
+
+class ClickHandlerParent extends JSWindowActorParent {
+  static addContentClickListener(listener) {
+    gContentClickListeners.add(listener);
+  }
+
+  static removeContentClickListener(listener) {
+    gContentClickListeners.delete(listener);
+  }
+
   receiveMessage(message) {
     switch (message.name) {
       case "Content:Click":
-        this.contentAreaClick(message.json, message.target);
+        this.contentAreaClick(message.data);
+        this.notifyClickListeners(message.data);
         break;
     }
-  },
+  }
 
   /**
    * Handles clicks in the content area.
    *
-   * @param json {Object} JSON object that looks like an Event
+   * @param data {Object} object that looks like an Event
    * @param browser {Element<browser>}
    */
-  contentAreaClick(json, browser) {
+  contentAreaClick(data) {
     // This is heavily based on contentAreaClick from browser.js (Bug 903016)
-    // The json is set up in a way to look like an Event.
+    // The data is set up in a way to look like an Event.
+    let browser = this.manager.browsingContext.top.embedderElement;
+    if (browser.outerBrowser) {
+      browser = browser.outerBrowser; // handle RDM mode
+    }
     let window = browser.ownerGlobal;
 
-    if (!json.href) {
+    if (!data.href) {
       // Might be middle mouse navigation.
       if (
         Services.prefs.getBoolPref("middlemouse.contentLoadURL") &&
         !Services.prefs.getBoolPref("general.autoScroll")
       ) {
-        window.middleMousePaste(json);
+        window.middleMousePaste(data);
       }
       return;
     }
 
     // If the browser is not in a place where we can open links, bail out.
     // This can happen in osx sheets, dialogs, etc. that are not browser
     // windows.  Specifically the payments UI is in an osx sheet.
     if (window.openLinkIn === undefined) {
@@ -65,44 +79,59 @@ var ContentClick = {
     }
 
     // Mark the page as a user followed link.  This is done so that history can
     // distinguish automatic embed visits from user activated ones.  For example
     // pages loaded in frames are embed visits and lost with the session, while
     // visits across frames should be preserved.
     try {
       if (!PrivateBrowsingUtils.isWindowPrivate(window)) {
-        PlacesUIUtils.markPageAsFollowedLink(json.href);
+        PlacesUIUtils.markPageAsFollowedLink(data.href);
       }
     } catch (ex) {
       /* Skip invalid URIs. */
     }
 
     // This part is based on handleLinkClick.
-    var where = window.whereToOpenLink(json);
+    var where = window.whereToOpenLink(data);
     if (where == "current") {
       return;
     }
 
     // Todo(903022): code for where == save
 
     let params = {
       charset: browser.characterSet,
-      referrerInfo: E10SUtils.deserializeReferrerInfo(json.referrerInfo),
-      allowMixedContent: json.allowMixedContent,
-      isContentWindowPrivate: json.isContentWindowPrivate,
-      originPrincipal: json.originPrincipal,
-      originStoragePrincipal: json.originStoragePrincipal,
-      triggeringPrincipal: json.triggeringPrincipal,
-      csp: json.csp ? E10SUtils.deserializeCSP(json.csp) : null,
-      frameOuterWindowID: json.frameOuterWindowID,
+      referrerInfo: E10SUtils.deserializeReferrerInfo(data.referrerInfo),
+      allowMixedContent: data.allowMixedContent,
+      isContentWindowPrivate: data.isContentWindowPrivate,
+      originPrincipal: data.originPrincipal,
+      originStoragePrincipal: data.originStoragePrincipal,
+      triggeringPrincipal: data.triggeringPrincipal,
+      csp: data.csp ? E10SUtils.deserializeCSP(data.csp) : null,
+      frameOuterWindowID: data.frameOuterWindowID,
     };
 
     // The new tab/window must use the same userContextId.
-    if (json.originAttributes.userContextId) {
-      params.userContextId = json.originAttributes.userContextId;
+    if (data.originAttributes.userContextId) {
+      params.userContextId = data.originAttributes.userContextId;
     }
 
     params.allowInheritPrincipal = true;
 
-    window.openLinkIn(json.href, where, params);
-  },
-};
+    window.openLinkIn(data.href, where, params);
+  }
+
+  notifyClickListeners(data) {
+    for (let listener of gContentClickListeners) {
+      try {
+        let browser = this.browsingContext.top.embedderElement;
+        if (browser.outerBrowser) {
+          browser = browser.outerBrowser; // Special-case responsive design mode
+        }
+
+        listener.onContentClick(browser, data);
+      } catch (ex) {
+        Cu.reportError(ex);
+      }
+    }
+  }
+}

--- a/browser/actors/moz.build
+++ b/browser/actors/moz.build
@@ -23,16 +23,17 @@ with Files("WebRTCChild.jsm"):
     BUG_COMPONENT = ("Firefox", "Site Permissions")
 
 FINAL_TARGET_FILES.actors += [
     'AboutReaderChild.jsm',
     'BlockedSiteChild.jsm',
     'BrowserTabChild.jsm',
     'BrowserTabParent.jsm',
     'ClickHandlerChild.jsm',
+    'ClickHandlerParent.jsm',
     'ContentMetaChild.jsm',
     'ContentMetaParent.jsm',
     'ContentSearchChild.jsm',
     'ContextMenuChild.jsm',
     'ContextMenuParent.jsm',
     'DOMFullscreenChild.jsm',
     'DOMFullscreenParent.jsm',
     'FormValidationChild.jsm',

--- a/browser/base/content/test/general/browser_contentAltClick.js
+++ b/browser/base/content/test/general/browser_contentAltClick.js
@@ -3,17 +3,17 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /**
  * Test for Bug 1109146.
  * The tests opens a new tab and alt + clicks to download files
  * and confirms those files are on the download list.
  *
  * The difference between this and the test "browser_contentAreaClick.js" is that
- * the code path in e10s uses ContentClick.jsm instead of browser.js::contentAreaClick() util.
+ * the code path in e10s uses the ClickHandler actor instead of browser.js::contentAreaClick() util.
  */
 "use strict";
 
 ChromeUtils.defineModuleGetter(
   this,
   "Downloads",
   "resource://gre/modules/Downloads.jsm"
 );
@@ -21,17 +21,18 @@ ChromeUtils.defineModuleGetter(
 function setup() {
   Services.prefs.setBoolPref("browser.altClickSave", true);
 
   let testPage =
     "data:text/html," +
     '<p><a id="commonlink" href="http://mochi.test/moz/">Common link</a></p>' +
     '<p><math id="mathlink" xmlns="http://www.w3.org/1998/Math/MathML" href="http://mochi.test/moz/"><mtext>MathML XLink</mtext></math></p>' +
     '<p><svg id="svgxlink" xmlns="http://www.w3.org/2000/svg" width="100px" height="50px" version="1.1"><a xlink:type="simple" xlink:href="http://mochi.test/moz/"><text transform="translate(10, 25)">SVG XLink</text></a></svg></p><br>' +
-    '<span id="host"></span><script>document.getElementById("host").attachShadow({mode: "closed"}).appendChild(document.getElementById("commonlink").cloneNode(true));</script>';
+    '<span id="host"></span><script>document.getElementById("host").attachShadow({mode: "closed"}).appendChild(document.getElementById("commonlink").cloneNode(true));</script>' +
+    '<iframe id="frame" src="https://test2.example.com:443/browser/browser/base/content/test/general/file_with_link_to_http.html"></iframe>';
 
   return BrowserTestUtils.openNewForegroundTab(gBrowser, testPage);
 }
 
 async function clean_up() {
   // Remove downloads.
   let downloadList = await Downloads.getList(Downloads.ALL);
   let downloads = await downloadList.getAll();
@@ -160,8 +161,46 @@ add_task(async function test_alt_click_o
   is(
     downloads[1].source.url,
     "http://mochi.test/moz/",
     "Downloaded #svgxlink element"
   );
 
   await clean_up();
 });
+
+// Alt+Click a link in a frame from another domain as the outer document.
+add_task(async function test_alt_click_in_frame() {
+  await setup();
+
+  let downloadList = await Downloads.getList(Downloads.ALL);
+  let downloads = [];
+  let downloadView;
+  // When the download has been attempted, resolve the promise.
+  let finishedAllDownloads = new Promise(resolve => {
+    downloadView = {
+      onDownloadAdded(aDownload) {
+        downloads.push(aDownload);
+        resolve();
+      },
+    };
+  });
+
+  await downloadList.addView(downloadView);
+  await BrowserTestUtils.synthesizeMouseAtCenter(
+    "#linkToExample",
+    { altKey: true },
+    gBrowser.selectedBrowser.browsingContext.getChildren()[0]
+  );
+
+  // Wait for all downloads to be added to the download list.
+  await finishedAllDownloads;
+  await downloadList.removeView(downloadView);
+
+  is(downloads.length, 1, "1 downloads");
+  is(
+    downloads[0].source.url,
+    "http://example.org/",
+    "Downloaded link in iframe."
+  );
+
+  await clean_up();
+});

--- a/browser/components/BrowserGlue.jsm
+++ b/browser/components/BrowserGlue.jsm
@@ -52,16 +52,31 @@ let ACTORS = {
         DOMWindowCreated: {},
         MozAfterPaint: {},
         "MozDOMPointerLock:Entered": {},
         "MozDOMPointerLock:Exited": {},
       },
     },
   },
 
+  ClickHandler: {
+    parent: {
+      moduleURI: "resource:///actors/ClickHandlerParent.jsm",
+    },
+    child: {
+      moduleURI: "resource:///actors/ClickHandlerChild.jsm",
+      events: {
+        click: { capture: true, mozSystemGroup: true },
+        auxclick: { capture: true, mozSystemGroup: true },
+      },
+    },
+
+    allFrames: true,
+  },
+
   // Collects description and icon information from meta tags.
   ContentMeta: {
     parent: {
       moduleURI: "resource:///actors/ContentMetaParent.jsm",
     },
 
     child: {
       moduleURI: "resource:///actors/ContentMetaChild.jsm",
@@ -308,26 +323,16 @@ let LEGACY_ACTORS = {
         click: {},
       },
       matches: ["about:blocked?*"],
       allFrames: true,
       messages: ["DeceptiveBlockedDetails"],
     },
   },
 
-  ClickHandler: {
-    child: {
-      module: "resource:///actors/ClickHandlerChild.jsm",
-      events: {
-        click: { capture: true, mozSystemGroup: true },
-        auxclick: { capture: true, mozSystemGroup: true },
-      },
-    },
-  },
-
   ContentSearch: {
     child: {
       module: "resource:///actors/ContentSearchChild.jsm",
       group: "browsers",
       matches: [
         "about:home",
         "about:newtab",
         "about:welcome",
@@ -562,17 +567,16 @@ XPCOMUtils.defineLazyModuleGetters(this,
   WebChannel: "resource://gre/modules/WebChannel.jsm",
   WindowsRegistry: "resource://gre/modules/WindowsRegistry.jsm",
 });
 
 // eslint-disable-next-line no-unused-vars
 XPCOMUtils.defineLazyModuleGetters(this, {
   AboutLoginsParent: "resource:///modules/AboutLoginsParent.jsm",
   AsyncPrefs: "resource://gre/modules/AsyncPrefs.jsm",
-  ContentClick: "resource:///modules/ContentClick.jsm",
   PluginManager: "resource:///actors/PluginParent.jsm",
   ReaderParent: "resource:///modules/ReaderParent.jsm",
 });
 
 /**
  * IF YOU ADD OR REMOVE FROM THIS LIST, PLEASE UPDATE THE LIST ABOVE AS WELL.
  * XXX Bug 1325373 is for making eslint detect these automatically.
  */
@@ -661,17 +665,16 @@ const listeners = {
     "AboutLogins:OpenMobileAndroid": ["AboutLoginsParent"],
     "AboutLogins:OpenMobileIos": ["AboutLoginsParent"],
     "AboutLogins:OpenSite": ["AboutLoginsParent"],
     "AboutLogins:SortChanged": ["AboutLoginsParent"],
     "AboutLogins:Subscribe": ["AboutLoginsParent"],
     "AboutLogins:SyncEnable": ["AboutLoginsParent"],
     "AboutLogins:SyncOptions": ["AboutLoginsParent"],
     "AboutLogins:UpdateLogin": ["AboutLoginsParent"],
-    "Content:Click": ["ContentClick"],
     ContentSearch: ["ContentSearch"],
     "Reader:FaviconRequest": ["ReaderParent"],
     "Reader:UpdateReaderButton": ["ReaderParent"],
     "rtcpeer:CancelRequest": ["webrtcUI"],
     "rtcpeer:Request": ["webrtcUI"],
     "webrtc:CancelRequest": ["webrtcUI"],
     "webrtc:Request": ["webrtcUI"],
     "webrtc:StopRecording": ["webrtcUI"],

--- a/browser/modules/moz.build
+++ b/browser/modules/moz.build
@@ -131,17 +131,16 @@ BROWSER_CHROME_MANIFESTS += [
 ]
 XPCSHELL_TESTS_MANIFESTS += ['test/unit/xpcshell.ini']
 
 EXTRA_JS_MODULES += [
     'AboutNewTab.jsm',
     'AsyncTabSwitcher.jsm',
     'BrowserUsageTelemetry.jsm',
     'BrowserWindowTracker.jsm',
-    'ContentClick.jsm',
     'ContentCrashHandlers.jsm',
     'ContentObservers.js',
     'ContentSearch.jsm',
     'Discovery.jsm',
     'EveryWindow.jsm',
     'ExtensionsUI.jsm',
     'FaviconLoader.jsm',
     'HomePage.jsm',

--- a/devtools/client/responsive/browser/tunnel.js
+++ b/devtools/client/responsive/browser/tunnel.js
@@ -42,20 +42,16 @@ const SWAPPED_BROWSER_STATE = [
  * When RDM is enabled, these bits of code instead reach the RDM tool's window instead of
  * the browser window, which won't have the properties they are looking for. At the
  * moment, we address this by exposing them from the browser window on RDM's window as
  * needed.
  */
 const PROPERTIES_FROM_BROWSER_WINDOW = [
   // This is used by PermissionUI.jsm for permission doorhangers.
   "PopupNotifications",
-  // These are used by ContentClick.jsm when opening links in ways other than just
-  // navigating the viewport, such as a new tab by pressing Cmd-Click.
-  "whereToOpenLink",
-  "openLinkIn",
   // This is used by various event handlers, typically to call `getTabForBrowser` to map
   // a browser back to a tab.
   "gBrowser",
 ];
 
 /**
  * This module takes an "outer" <xul:browser> from a browser tab as described by
  * Firefox's tabbrowser.xml and wires it up to an "inner" <iframe mozbrowser>

--- a/toolkit/components/extensions/WebNavigation.jsm
+++ b/toolkit/components/extensions/WebNavigation.jsm
@@ -18,16 +18,21 @@ ChromeUtils.defineModuleGetter(
   "PrivateBrowsingUtils",
   "resource://gre/modules/PrivateBrowsingUtils.jsm"
 );
 ChromeUtils.defineModuleGetter(
   this,
   "UrlbarUtils",
   "resource:///modules/UrlbarUtils.jsm"
 );
+ChromeUtils.defineModuleGetter(
+  this,
+  "ClickHandlerParent",
+  "resource:///actors/ClickHandlerParent.jsm"
+);
 
 // Maximum amount of time that can be passed and still consider
 // the data recent (similar to how is done in nsNavHistory,
 // e.g. nsNavHistory::CheckIsRecentEvent, but with a lower threshold value).
 const RECENT_DATA_THRESHOLD = 5 * 1000000;
 
 var Manager = {
   // Map[string -> Map[listener -> URLFilter]]
@@ -42,17 +47,18 @@ var Manager = {
     // pair the message received from the source tab to the one received from
     // the new tab.
     this.createdNavigationTargetByOuterWindowId = new Map();
 
     Services.obs.addObserver(this, "urlbar-user-start-navigation", true);
 
     Services.obs.addObserver(this, "webNavigation-createdNavigationTarget");
 
-    Services.mm.addMessageListener("Content:Click", this);
+    ClickHandlerParent.addContentClickListener(this);
+
     Services.mm.addMessageListener("Extension:DOMContentLoaded", this);
     Services.mm.addMessageListener("Extension:StateChange", this);
     Services.mm.addMessageListener("Extension:DocumentChange", this);
     Services.mm.addMessageListener("Extension:HistoryChange", this);
     Services.mm.addMessageListener("Extension:CreatedNavigationTarget", this);
 
     Services.mm.loadFrameScript(
       "resource://gre/modules/WebNavigationContent.js",
@@ -60,17 +66,18 @@ var Manager = {
     );
   },
 
   uninit() {
     // Stop collecting recent tab transition data and reset the WeakMap.
     Services.obs.removeObserver(this, "urlbar-user-start-navigation");
     Services.obs.removeObserver(this, "webNavigation-createdNavigationTarget");
 
-    Services.mm.removeMessageListener("Content:Click", this);
+    ClickHandlerParent.removeContentClickListener(this);
+
     Services.mm.removeMessageListener("Extension:StateChange", this);
     Services.mm.removeMessageListener("Extension:DocumentChange", this);
     Services.mm.removeMessageListener("Extension:HistoryChange", this);
     Services.mm.removeMessageListener("Extension:DOMContentLoaded", this);
     Services.mm.removeMessageListener(
       "Extension:CreatedNavigationTarget",
       this
     );
@@ -300,20 +307,16 @@ var Manager = {
       case "Extension:HistoryChange":
         this.onHistoryChange(target, data);
         break;
 
       case "Extension:DOMContentLoaded":
         this.onLoad(target, data);
         break;
 
-      case "Content:Click":
-        this.onContentClick(target, data);
-        break;
-
       case "Extension:CreatedNavigationTarget":
         this.onCreatedNavigationTarget(target, data);
         break;
     }
   },
 
   onContentClick(target, data) {
     // We are interested only on clicks to links which are not "add to bookmark" commands