diff --git a/Extension/browser/chrome/lib/api/background-page.js b/Extension/browser/chrome/lib/api/background-page.js
index a84dff430a..6b340c5a4e 100644
--- a/Extension/browser/chrome/lib/api/background-page.js
+++ b/Extension/browser/chrome/lib/api/background-page.js
@@ -301,6 +301,9 @@
         },
         setPopup: function () {
             // Do nothing. Popup is already installed in manifest file
+        },
+        close: function () {
+            // Do nothing
         }
     };
 
diff --git a/Extension/browser/firefox/lib/mobileMenu.js b/Extension/browser/firefox/lib/mobileMenu.js
index 1b79b782d9..d6870915db 100644
--- a/Extension/browser/firefox/lib/mobileMenu.js
+++ b/Extension/browser/firefox/lib/mobileMenu.js
@@ -24,9 +24,7 @@ var MobileMenu = {
 
     nativeMenuIds: Object.create(null),
 
-    init: function (UI) {
-
-        this.UI = UI;
+    init: function () {
 
         adguard.windowsImpl.onUpdated.addListener(function (adgWin, domWin, event) {
             if (event === 'ChromeWindowLoad') {
@@ -190,15 +188,15 @@ var MobileMenu = {
             name: "Adguard",
             icon: null
         });
-        MobileMenu.createSubMenus(window, menuID);
+        this.createSubMenus(window, menuID);
     },
 
     /**
      * @param window
      */
     removeFromWindow: function (window) {
-        if (window in MobileMenu.nativeMenuIds) {
-            var menuId = MobileMenu.nativeMenuIds[window].main;
+        if (window in this.nativeMenuIds) {
+            var menuId = this.nativeMenuIds[window].main;
             window.NativeWindow.menu.remove(menuId);
         }
     }
diff --git a/Extension/browser/firefox/lib/prefs.js b/Extension/browser/firefox/lib/prefs.js
index 0ffecbef25..4d31b8f8f3 100644
--- a/Extension/browser/firefox/lib/prefs.js
+++ b/Extension/browser/firefox/lib/prefs.js
@@ -51,7 +51,6 @@ var Prefs = {
     speedupStartup: function () {
         return SimplePrefs.get('speedup_startup');
     },
-    collapseByContentScript: true, // SimplePrefs.get('collapse_by_content_script'),
     useGlobalStyleSheet: SimplePrefs.get('use_global_style_sheet'),
 
     ICONS: {
@@ -71,13 +70,10 @@ var Prefs = {
 };
 
 var onPreferenceChanged = function (prefName) {
-    Prefs.collapseByContentScript = SimplePrefs.get('collapse_by_content_script');
     Prefs.useGlobalStyleSheet = SimplePrefs.get('use_global_style_sheet');
     EventNotifier.notifyListeners(EventNotifierTypes.CHANGE_PREFS, prefName);
 };
-SimplePrefs.addListener('collapse_by_content_script', onPreferenceChanged);
 SimplePrefs.addListener('use_global_style_sheet', onPreferenceChanged);
 unload.when(function () {
-    SimplePrefs.removeListener('collapse_by_content_script', onPreferenceChanged);
     SimplePrefs.removeListener('use_global_style_sheet', onPreferenceChanged);
 });
\ No newline at end of file
diff --git a/Extension/browser/firefox/package.json b/Extension/browser/firefox/package.json
index d9f52961b1..0698aaad25 100644
--- a/Extension/browser/firefox/package.json
+++ b/Extension/browser/firefox/package.json
@@ -18,13 +18,6 @@
 			"title": "Speedup startup",
             "description": "Enables asynchronous filters initialization"
 		},
-        {
-            "type": "bool",
-            "name": "collapse_by_content_script",
-            "value": true,
-            "title": "Collapse by content script",
-            "description": "Enables asynchronous elements blocking by the content script"
-        },
         {
             "type": "bool",
             "name": "use_global_style_sheet",
diff --git a/Extension/lib/content-message-handler.js b/Extension/lib/content-message-handler.js
index ea077188c6..4e54de85bc 100644
--- a/Extension/lib/content-message-handler.js
+++ b/Extension/lib/content-message-handler.js
@@ -144,12 +144,6 @@ ContentMessageHandler.prototype = {
                 var block = webRequestService.checkWebSocketRequest(sender.tab, message.elementUrl, message.documentUrl);
                 return {block: block, requestId: message.requestId};
             case 'processShouldCollapse':
-
-                if (!Prefs.collapseByContentScript) {
-                    // In case of FF we may collapse nodes with nsiContentPolicy
-                    return {collapse: false, requestId: message.requestId};
-                }
-
                 var collapse = webRequestService.processShouldCollapse(sender.tab, message.elementUrl, message.documentUrl, message.requestType);
                 return {collapse: collapse, requestId: message.requestId};
             case 'processShouldCollapseMany':
diff --git a/Extension/lib/pages/popup.js b/Extension/lib/pages/popup.js
index 2c7e90b446..b1718fdcb2 100644
--- a/Extension/lib/pages/popup.js
+++ b/Extension/lib/pages/popup.js
@@ -18,7 +18,6 @@
 /* global $, PopupController */
 var backgroundPage = adguard.backgroundPage.getWindow();
 var antiBannerService = backgroundPage.antiBannerService;
-var UI = backgroundPage.UI;
 var uiService = backgroundPage.uiService;
 var framesMap = backgroundPage.framesMap;
 var filteringLog = backgroundPage.filteringLog;
@@ -96,7 +95,7 @@ $(document).ready(function () {
             adguard.closePopup();
         };
         controller.openLink = function (url) {
-            UI.openTab(url);
+            uiService.openTab(url);
             adguard.closePopup();
         };
         controller.openFilteringLog = function (tabId) {