diff --git a/app/src/common/shared/org/mozilla/vrbrowser/VRBrowserActivity.java b/app/src/common/shared/org/mozilla/vrbrowser/VRBrowserActivity.java
index 402478c56..270fc8e94 100644
--- a/app/src/common/shared/org/mozilla/vrbrowser/VRBrowserActivity.java
+++ b/app/src/common/shared/org/mozilla/vrbrowser/VRBrowserActivity.java
@@ -93,9 +93,11 @@
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedList;
+import java.util.Objects;
 import java.util.Set;
 import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.function.Consumer;
+import java.util.function.Function;
 
 import static org.mozilla.vrbrowser.ui.widgets.UIWidget.REMOVE_WIDGET;
 
@@ -392,6 +394,20 @@ public void onWindowVideoAvailabilityChanged(@NonNull WindowWidget aWindow) {
             mWhatsNewWidget.getPlacement().parentHandle = mWindows.getFocusedWindow().getHandle();
             mWhatsNewWidget.show(UIWidget.REQUEST_FOCUS);
         }
+
+        EngineProvider.INSTANCE.loadExtensions()
+                .thenAcceptAsync(aVoid -> {
+                    Log.d(LOGTAG, "WebExtensions loaded");
+                    mWindows.restoreSessions();
+                }, getServicesProvider().getExecutors().mainThread())
+                .exceptionally(throwable -> {
+                    String msg = throwable.getLocalizedMessage();
+                    if (msg != null) {
+                        Log.e(LOGTAG, "Extensions load error: " + msg);
+                    }
+                    mWindows.restoreSessions();
+                    return null;
+                });
     }
 
     private void attachToWindow(@NonNull WindowWidget aWindow, @Nullable WindowWidget aPrevWindow) {
diff --git a/app/src/common/shared/org/mozilla/vrbrowser/browser/engine/EngineProvider.kt b/app/src/common/shared/org/mozilla/vrbrowser/browser/engine/EngineProvider.kt
index a646e6c7b..bcf68bf5c 100644
--- a/app/src/common/shared/org/mozilla/vrbrowser/browser/engine/EngineProvider.kt
+++ b/app/src/common/shared/org/mozilla/vrbrowser/browser/engine/EngineProvider.kt
@@ -11,6 +11,7 @@ import org.mozilla.vrbrowser.browser.SettingsStore
 import org.mozilla.vrbrowser.browser.content.TrackingProtectionPolicy
 import org.mozilla.vrbrowser.browser.content.TrackingProtectionStore
 import org.mozilla.vrbrowser.crashreporting.CrashReporterService
+import java.util.concurrent.CompletableFuture
 
 object EngineProvider {
 
@@ -54,15 +55,23 @@ object EngineProvider {
             }
 
             runtime = GeckoRuntime.create(context, builder.build())
-            for (extension in WEB_EXTENSIONS) {
-                val path = "resource://android/assets/web_extensions/$extension/"
-                runtime!!.registerWebExtension(WebExtension(path, runtime!!.webExtensionController))
-            }
         }
 
         return runtime!!
     }
 
+    fun loadExtensions() : CompletableFuture<Void> {
+        val futures : List<CompletableFuture<Void>> = WEB_EXTENSIONS.map {
+            val future = CompletableFuture<Void>()
+            val url = "resource://android/assets/web_extensions/$it/"
+            runtime!!.webExtensionController.installBuiltIn(url).accept {
+                future.complete(null)
+            }
+            future
+        }
+        return CompletableFuture.allOf(*futures.toTypedArray())
+    }
+
     fun createGeckoWebExecutor(context: Context): GeckoWebExecutor {
         return GeckoWebExecutor(getOrCreateRuntime(context))
     }
diff --git a/app/src/common/shared/org/mozilla/vrbrowser/ui/widgets/Windows.java b/app/src/common/shared/org/mozilla/vrbrowser/ui/widgets/Windows.java
index 4a077cd9c..d9625282f 100644
--- a/app/src/common/shared/org/mozilla/vrbrowser/ui/widgets/Windows.java
+++ b/app/src/common/shared/org/mozilla/vrbrowser/ui/widgets/Windows.java
@@ -39,7 +39,6 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
-import java.util.function.Predicate;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -134,6 +133,8 @@ class WindowsState {
     private Services mServices;
     private PromptDialogWidget mNoInternetDialog;
     private boolean mCompositorPaused = false;
+    private WindowsState mWindowsState;
+    private boolean mIsRestoreEnabled;
 
     public enum PanelType {
         NONE,
@@ -182,6 +183,8 @@ public Windows(Context aContext) {
 
         mWidgetManager.addConnectivityListener(mConnectivityDelegate);
 
+        mIsRestoreEnabled = SettingsStore.getInstance(mContext).isRestoreTabsEnabled();
+        mWindowsState = restoreState();
         restoreWindows();
     }
 
@@ -698,35 +701,12 @@ private WindowWidget getRightWindow() {
     }
 
     private void restoreWindows() {
-        boolean restoreEnabled = SettingsStore.getInstance(mContext).isRestoreTabsEnabled();
-        WindowsState windowsState = restoreState();
-        if (restoreEnabled && windowsState != null) {
-            ArrayList<Session> restoredSessions = new ArrayList<>();
-            if (windowsState.tabs != null) {
-                windowsState.tabs.forEach(state -> {
-                    restoredSessions.add(SessionStore.get().createSuspendedSession(state));
-                    GleanMetricsService.Tabs.openedCounter(GleanMetricsService.Tabs.TabSource.PRE_EXISTING);
-                });
-            }
-            mPrivateMode = false;
-            for (WindowState windowState : windowsState.regularWindowsState) {
-                if (windowState.tabIndex >= 0 && windowState.tabIndex < restoredSessions.size()) {
-                    addRestoredWindow(windowState, restoredSessions.get(windowState.tabIndex));
-                } else if (windowState.tabIndex < 0) {
-                    WindowWidget widget = addRestoredWindow(windowState, null);
-                    if ((widget != null) && (widget.getSession() != null)) {
-                        widget.getSession().loadHomePage();
-                    }
-                }
-            }
-            mPrivateMode = !windowsState.privateMode;
-            if (windowsState.privateMode) {
-                enterPrivateMode();
-            } else {
-                exitPrivateMode();
+        if (mIsRestoreEnabled && mWindowsState != null) {
+            for (WindowState windowState : mWindowsState.regularWindowsState) {
+                addRestoredWindow(windowState, null);
             }
 
-            WindowWidget windowToFocus = getWindowWithPlacement(windowsState.focusedWindowPlacement);
+            WindowWidget windowToFocus = getWindowWithPlacement(mWindowsState.focusedWindowPlacement);
             if (windowToFocus == null) {
                 windowToFocus = getFrontWindow();
                 if (windowToFocus == null && getCurrentWindows().size() > 0) {
@@ -746,6 +726,43 @@ private void restoreWindows() {
         updateViews();
     }
 
+    public void restoreSessions() {
+        if (mIsRestoreEnabled && mWindowsState != null) {
+            ArrayList<Session> restoredSessions = new ArrayList<>();
+            if (mWindowsState.tabs != null) {
+                mWindowsState.tabs.forEach(state -> {
+                    restoredSessions.add(SessionStore.get().createSuspendedSession(state));
+                    GleanMetricsService.Tabs.openedCounter(GleanMetricsService.Tabs.TabSource.PRE_EXISTING);
+                });
+            }
+
+            for (WindowState windowState : mWindowsState.regularWindowsState) {
+                WindowWidget targetWindow = getWindowWithPlacement(windowState.placement);
+                if (targetWindow != null) {
+                    if (windowState.tabIndex >= 0 && windowState.tabIndex < restoredSessions.size()) {
+                        Session defaultSession = targetWindow.getSession();
+                        Session session = restoredSessions.get(windowState.tabIndex);
+                        targetWindow.setupListeners(session);
+                        session.setActive(true);
+                        targetWindow.setSession(session);
+                        SessionStore.get().setActiveSession(session);
+                        // Destroy the default blank session
+                        SessionStore.get().destroySession(defaultSession);
+
+                    } else {
+                        targetWindow.loadHome();
+                    }
+                }
+            }
+
+            if (mWindowsState.privateMode) {
+                enterPrivateMode();
+            } else {
+                exitPrivateMode();
+            }
+        }
+    }
+
     private void removeWindow(@NonNull WindowWidget aWindow) {
         BitmapCache.getInstance(mContext).removeBitmap(aWindow.getSession().getId());
         mWidgetManager.removeWidget(aWindow);
diff --git a/app/src/main/assets/web_extensions/webcompat_vimeo/manifest.json b/app/src/main/assets/web_extensions/webcompat_vimeo/manifest.json
index 8713592a9..ce3262d41 100644
--- a/app/src/main/assets/web_extensions/webcompat_vimeo/manifest.json
+++ b/app/src/main/assets/web_extensions/webcompat_vimeo/manifest.json
@@ -3,6 +3,11 @@
   "name": "Firefox Reality Vimeo.com WebCompat Enhancements",
   "version": "1.0",
   "description": "Fixes web-site compatibility quirks for Vimeo.com when using Firefox Reality.",
+  "browser_specific_settings": {
+    "gecko": {
+      "id": "fxr-webcompat_vimeo@mozilla.org"
+    }
+  },
   "content_scripts": [
     {
       "matches": [
diff --git a/app/src/main/assets/web_extensions/webcompat_youtube/manifest.json b/app/src/main/assets/web_extensions/webcompat_youtube/manifest.json
index 34d24e240..a2e7527da 100644
--- a/app/src/main/assets/web_extensions/webcompat_youtube/manifest.json
+++ b/app/src/main/assets/web_extensions/webcompat_youtube/manifest.json
@@ -3,6 +3,11 @@
   "name": "Firefox Reality YouTube.com WebCompat Enhancements",
   "version": "1.0",
   "description": "Fixes web-site compatibility quirks for YouTube.com when using Firefox Reality.",
+  "browser_specific_settings": {
+    "gecko": {
+      "id": "fxr-webcompat_youtube@mozilla.org"
+    }
+  },
   "content_scripts": [
     {
       "matches": [