--- a/browser/components/originattributes/test/browser/browser_favicon_firstParty.js
+++ b/browser/components/originattributes/test/browser/browser_favicon_firstParty.js
@@ -1,16 +1,20 @@
 /**
  * Bug 1277803 - A test case for testing favicon loading across different first party domains.
  */
 
 const { classes: Cc, Constructor: CC, interfaces: Ci, utils: Cu } = Components;
 
 Cu.import("resource://gre/modules/PlacesUtils.jsm");
 
+let EventUtils = {};
+Services.scriptloader.loadSubScript(
+  "chrome://mochikit/content/tests/SimpleTest/EventUtils.js", EventUtils);
+
 const FIRST_PARTY_ONE = "example.com";
 const FIRST_PARTY_TWO = "example.org";
 const THIRD_PARTY = "mochi.test:8888";
 
 const TEST_SITE_ONE = "http://" + FIRST_PARTY_ONE;
 const TEST_SITE_TWO = "http://" + FIRST_PARTY_TWO;
 const THIRD_PARTY_SITE = "http://" + THIRD_PARTY;
 const TEST_DIRECTORY = "/browser/browser/components/originattributes/test/browser/";
@@ -47,19 +51,20 @@ function clearAllPlacesFavicons() {
       }
     };
 
     Services.obs.addObserver(observer, "places-favicons-expired");
     faviconService.expireAllFavicons();
   });
 }
 
-function observeFavicon(aFirstPartyDomain, aExpectedCookie, aPageURI) {
+function observeFavicon(aFirstPartyDomain, aExpectedCookie, aPageURI, aOnlyXUL) {
   let faviconReqXUL = false;
-  let faviconReqPlaces = false;
+  // If aOnlyXUL is true, we only care about the favicon request from XUL.
+  let faviconReqPlaces = aOnlyXUL === true;
   let expectedPrincipal = Services.scriptSecurityManager
                                   .createCodebasePrincipal(aPageURI, { firstPartyDomain: aFirstPartyDomain });
 
   return new Promise(resolve => {
     let observer = {
       observe(aSubject, aTopic, aData) {
         // Make sure that the topic is 'http-on-modify-request'.
         if (aTopic === "http-on-modify-request") {
@@ -239,16 +244,95 @@ async function doTest(aTestPage, aExpect
   tabInfo = await openTab(TEST_SITE_TWO + aTestPage);
 
   // Waiting until favicon requests are all made.
   await promiseObserveFavicon;
 
   await BrowserTestUtils.removeTab(tabInfo.tab);
 }
 
+async function doTestForAllTabsFavicon(aTestPage, aExpectedCookies, aIsThirdParty) {
+  let firstPageURI = makeURI(TEST_SITE_ONE + aTestPage);
+  let secondPageURI = makeURI(TEST_SITE_TWO + aTestPage);
+  let faviconURI = aIsThirdParty ? THIRD_PARTY_SITE + FAVICON_URI :
+                                   TEST_SITE_ONE + FAVICON_URI;
+
+  // Set the 'overflow' attribute to make allTabs button available.
+  let tabBrowser = document.getElementById("tabbrowser-tabs");
+  let allTabsBtn = document.getElementById("alltabs-button");
+  tabBrowser.setAttribute("overflow", true);
+
+  // Start to observe the event of that the favicon has been fully loaded.
+  let promiseFaviconLoaded = waitOnFaviconLoaded(faviconURI);
+
+  // Open the tab for the first site.
+  let tabInfo = await openTab(TEST_SITE_ONE + aTestPage);
+
+  // Waiting until the favicon loaded.
+  await promiseFaviconLoaded;
+
+  // We need to clear the image cache here for making sure the network request will
+  // be made for the favicon of allTabs menuitem.
+  clearAllImageCaches();
+
+  // Start to observe the allTabs favicon requests earlier in case we miss it.
+  let promiseObserveFavicon = observeFavicon(FIRST_PARTY_ONE, aExpectedCookies[0],
+                                             firstPageURI, true);
+
+  // Make the popup of allTabs showing up and trigger the loading of the favicon.
+  let allTabsPopupShownPromise = BrowserTestUtils.waitForEvent(allTabsBtn, "popupshown");
+  EventUtils.synthesizeMouseAtCenter(allTabsBtn, {});
+  await promiseObserveFavicon;
+  await allTabsPopupShownPromise;
+
+  // Close the popup of allTabs and wait until it's done.
+  let allTabsPopupHiddenPromise = BrowserTestUtils.waitForEvent(allTabsBtn, "popuphidden");
+  EventUtils.synthesizeMouseAtCenter(allTabsBtn, {});
+  await allTabsPopupHiddenPromise;
+
+  // Close the tab.
+  await BrowserTestUtils.removeTab(tabInfo.tab);
+
+  faviconURI = aIsThirdParty ? THIRD_PARTY_SITE + FAVICON_URI :
+                               TEST_SITE_TWO + FAVICON_URI;
+
+  // Start to observe the event of that favicon has been fully loaded.
+  promiseFaviconLoaded = waitOnFaviconLoaded(faviconURI);
+
+  // Open the tab for the second site.
+  tabInfo = await openTab(TEST_SITE_TWO + aTestPage);
+
+  // Wait until the favicon is fully loaded.
+  await promiseFaviconLoaded;
+
+  // Clear the image cache for the favicon of the second site.
+  clearAllImageCaches();
+
+  // Start to observe the allTabs favicon requests earlier in case we miss it.
+  promiseObserveFavicon = observeFavicon(FIRST_PARTY_TWO, aExpectedCookies[1],
+                                         secondPageURI, true);
+
+  // Make the popup of allTabs showing up again.
+  allTabsPopupShownPromise = BrowserTestUtils.waitForEvent(allTabsBtn, "popupshown");
+  EventUtils.synthesizeMouseAtCenter(allTabsBtn, {});
+  await promiseObserveFavicon;
+  await allTabsPopupShownPromise;
+
+  // Close the popup of allTabs and wait until it's done.
+  allTabsPopupHiddenPromise = BrowserTestUtils.waitForEvent(allTabsBtn, "popuphidden");
+  EventUtils.synthesizeMouseAtCenter(allTabsBtn, {});
+  await allTabsPopupHiddenPromise;
+
+  // Close the tab.
+  await BrowserTestUtils.removeTab(tabInfo.tab);
+
+  // Reset the 'overflow' attribute to make the allTabs button hidden again.
+  tabBrowser.removeAttribute("overflow");
+}
+
 add_task(async function setup() {
   // Make sure first party isolation is enabled.
   await SpecialPowers.pushPrefEnv({"set": [
       ["privacy.firstparty.isolate", true]
   ]});
 });
 
 // A clean up function to prevent affecting other tests.
@@ -277,16 +361,36 @@ add_task(async function test_favicon_fir
     if (testThirdParty) {
       await doTest(TEST_THIRD_PARTY_PAGE, cookies, THIRD_PARTY_SITE + FAVICON_URI);
     } else {
       await doTest(TEST_PAGE, cookies, TEST_SITE_ONE + FAVICON_URI);
     }
   }
 });
 
+add_task(async function test_allTabs_favicon_firstParty() {
+  for (let testThirdParty of [false, true]) {
+    // Clear all image caches and network caches before running the test.
+    clearAllImageCaches();
+
+    Services.cache2.clear();
+
+    // Clear Places favicon caches.
+    await clearAllPlacesFavicons();
+
+    let cookies = await generateCookies(testThirdParty);
+
+    if (testThirdParty) {
+      await doTestForAllTabsFavicon(TEST_THIRD_PARTY_PAGE, cookies, testThirdParty);
+    } else {
+      await doTestForAllTabsFavicon(TEST_PAGE, cookies, testThirdParty);
+    }
+  }
+});
+
 add_task(async function test_favicon_cache_firstParty() {
   // Clear all image caches and network caches before running the test.
   clearAllImageCaches();
 
   Services.cache2.clear();
 
   // Start to observer the event of that favicon has been fully loaded and cached.
   let promiseForFaviconLoaded = waitOnFaviconLoaded(THIRD_PARTY_SITE + TEST_FAVICON_CACHE_URI);

--- a/browser/components/originattributes/test/browser/browser_favicon_userContextId.js
+++ b/browser/components/originattributes/test/browser/browser_favicon_userContextId.js
@@ -2,16 +2,20 @@
  * Bug 1277803 - A test caes for testing favicon loading across different userContextId.
  */
 
 const { classes: Cc, Constructor: CC, interfaces: Ci, utils: Cu } = Components;
 
 XPCOMUtils.defineLazyModuleGetter(this, "Promise",
   "resource://gre/modules/Promise.jsm");
 
+let EventUtils = {};
+Services.scriptloader.loadSubScript(
+  "chrome://mochikit/content/tests/SimpleTest/EventUtils.js", EventUtils);
+
 const TEST_SITE = "http://example.net";
 const TEST_THIRD_PARTY_SITE = "http://mochi.test:8888";
 
 const TEST_PAGE = TEST_SITE + "/browser/browser/components/originattributes/" +
                   "test/browser/file_favicon.html";
 const FAVICON_URI = TEST_SITE + "/browser/browser/components/originattributes/" +
                     "test/browser/file_favicon.png";
 const TEST_THIRD_PARTY_PAGE = "http://example.com/browser/browser/components/" +
@@ -47,18 +51,18 @@ function clearAllPlacesFavicons() {
       }
     };
 
     Services.obs.addObserver(observer, "places-favicons-expired");
     faviconService.expireAllFavicons();
   });
 }
 
-function FaviconObserver(aUserContextId, aExpectedCookie, aPageURI, aFaviconURL) {
-  this.reset(aUserContextId, aExpectedCookie, aPageURI, aFaviconURL);
+function FaviconObserver(aUserContextId, aExpectedCookie, aPageURI, aFaviconURL, aOnlyXUL) {
+  this.reset(aUserContextId, aExpectedCookie, aPageURI, aFaviconURL, aOnlyXUL);
 }
 
 FaviconObserver.prototype = {
   observe(aSubject, aTopic, aData) {
     // Make sure that the topic is 'http-on-modify-request'.
     if (aTopic === "http-on-modify-request") {
       // We check the userContextId for the originAttributes of the loading
       // channel. All requests for the favicon should contain the correct
@@ -103,23 +107,24 @@ FaviconObserver.prototype = {
       ok(false, "Received unexpected topic: ", aTopic);
     }
 
     if (this._faviconReqXUL && this._faviconReqPlaces) {
       this._faviconLoaded.resolve();
     }
   },
 
-  reset(aUserContextId, aExpectedCookie, aPageURI, aFaviconURL) {
+  reset(aUserContextId, aExpectedCookie, aPageURI, aFaviconURL, aOnlyXUL) {
     this._curUserContextId = aUserContextId;
     this._expectedCookie = aExpectedCookie;
     this._expectedPrincipal = Services.scriptSecurityManager
                                       .createCodebasePrincipal(aPageURI, { userContextId: aUserContextId });
     this._faviconReqXUL = false;
-    this._faviconReqPlaces = false;
+    // If aOnlyXUL is true, we only care about the favicon request from XUL.
+    this._faviconReqPlaces = aOnlyXUL === true;
     this._faviconURL = aFaviconURL;
     this._faviconLoaded = new Promise.defer();
   },
 
   get promise() {
     return this._faviconLoaded.promise;
   }
 };
@@ -196,16 +201,97 @@ async function doTest(aTestPage, aFavico
   // Waiting for favicon requests are all made.
   await observer.promise;
 
   Services.obs.removeObserver(observer, "http-on-modify-request");
 
   await BrowserTestUtils.removeTab(tabInfo.tab);
 }
 
+async function doTestForAllTabsFavicon(aTestPage, aFaviconHost, aFaviconURL) {
+  let cookies = await generateCookies(aFaviconHost);
+  let pageURI = makeURI(aTestPage);
+
+  // Set the 'overflow' attribute to make allTabs button available.
+  let tabBrowser = document.getElementById("tabbrowser-tabs");
+  let allTabsBtn = document.getElementById("alltabs-button");
+  tabBrowser.setAttribute("overflow", true);
+
+  // Create the observer object for observing request channels of the personal
+  // container.
+  let observer = new FaviconObserver(USER_CONTEXT_ID_PERSONAL, cookies[0], pageURI, aFaviconURL, true);
+
+  // Add the observer earlier in case we miss it.
+  let promiseWaitOnFaviconLoaded = waitOnFaviconLoaded(aFaviconURL);
+
+  // Open the tab with the personal container.
+  let tabInfo = await openTabInUserContext(aTestPage, USER_CONTEXT_ID_PERSONAL);
+
+  // Waiting for favicon loaded.
+  await promiseWaitOnFaviconLoaded;
+
+  // We need to clear the image cache here for making sure the network request will
+  // be made for the favicon of allTabs menuitem.
+  clearAllImageCaches();
+
+  // Add the observer for listening favicon requests.
+  Services.obs.addObserver(observer, "http-on-modify-request");
+
+  // Make the popup of allTabs showing up and trigger the loading of the favicon.
+  let allTabsPopupShownPromise = BrowserTestUtils.waitForEvent(allTabsBtn, "popupshown");
+  EventUtils.synthesizeMouseAtCenter(allTabsBtn, {});
+  await observer.promise;
+  await allTabsPopupShownPromise;
+
+  // Close the popup of allTabs and wait until it's done.
+  let allTabsPopupHiddenPromise = BrowserTestUtils.waitForEvent(allTabsBtn, "popuphidden");
+  EventUtils.synthesizeMouseAtCenter(allTabsBtn, {});
+  await allTabsPopupHiddenPromise;
+
+  // Remove the observer for not receiving the favicon requests for opening a tab
+  // since we want to focus on the favicon of allTabs menu here.
+  Services.obs.removeObserver(observer, "http-on-modify-request");
+
+  // Close the tab.
+  await BrowserTestUtils.removeTab(tabInfo.tab);
+
+  // Open the tab under the work container and wait until the favicon is loaded.
+  promiseWaitOnFaviconLoaded = waitOnFaviconLoaded(aFaviconURL);
+  tabInfo = await openTabInUserContext(aTestPage, USER_CONTEXT_ID_WORK);
+  await promiseWaitOnFaviconLoaded;
+
+  // Clear the image cache again.
+  clearAllImageCaches();
+
+  // Reset the observer for observing requests for the work container.
+  observer.reset(USER_CONTEXT_ID_WORK, cookies[1], pageURI, aFaviconURL, true);
+
+  // Add the observer back for listening the favicon requests for allTabs menuitem.
+  Services.obs.addObserver(observer, "http-on-modify-request");
+
+  // Make the popup of allTabs showing up again.
+  allTabsPopupShownPromise = BrowserTestUtils.waitForEvent(allTabsBtn, "popupshown");
+  EventUtils.synthesizeMouseAtCenter(allTabsBtn, {});
+  await observer.promise;
+  await allTabsPopupShownPromise;
+
+  // Close the popup of allTabs and wait until it's done.
+  allTabsPopupHiddenPromise = BrowserTestUtils.waitForEvent(allTabsBtn, "popuphidden");
+  EventUtils.synthesizeMouseAtCenter(allTabsBtn, {});
+  await allTabsPopupHiddenPromise;
+
+  Services.obs.removeObserver(observer, "http-on-modify-request");
+
+  // Close the tab.
+  await BrowserTestUtils.removeTab(tabInfo.tab);
+
+  // Reset the 'overflow' attribute to make the allTabs button hidden again.
+  tabBrowser.removeAttribute("overflow");
+}
+
 add_task(async function setup() {
   // Make sure userContext is enabled.
   await SpecialPowers.pushPrefEnv({"set": [
       ["privacy.userContext.enabled", true]
   ]});
 });
 
 // A clean up function to prevent affecting other tests.
@@ -242,8 +328,34 @@ add_task(async function test_thirdPartyF
   // Clear all network caches.
   Services.cache2.clear();
 
   // Clear Places favicon caches.
   await clearAllPlacesFavicons();
 
   await doTest(TEST_THIRD_PARTY_PAGE, TEST_THIRD_PARTY_SITE, THIRD_PARTY_FAVICON_URI);
 });
+
+add_task(async function test_allTabs_favicon_userContextId() {
+  // Clear all image caches before running the test.
+  clearAllImageCaches();
+
+  // Clear all network caches.
+  Services.cache2.clear();
+
+  // Clear Places favicon caches.
+  await clearAllPlacesFavicons();
+
+  await doTestForAllTabsFavicon(TEST_PAGE, TEST_SITE, FAVICON_URI);
+});
+
+add_task(async function test_allTabs_thirdPartyFavicon_userContextId() {
+  // Clear all image caches before running the test.
+  clearAllImageCaches();
+
+  // Clear all network caches.
+  Services.cache2.clear();
+
+  // Clear Places favicon caches.
+  await clearAllPlacesFavicons();
+
+  await doTestForAllTabsFavicon(TEST_THIRD_PARTY_PAGE, TEST_THIRD_PARTY_SITE, THIRD_PARTY_FAVICON_URI);
+});