diff --git a/dom/workers/ServiceWorkerClients.cpp b/dom/workers/ServiceWorkerClients.cpp
index a30f15235676..fe9c17937b24 100644
--- a/dom/workers/ServiceWorkerClients.cpp
+++ b/dom/workers/ServiceWorkerClients.cpp
@@ -33,6 +33,10 @@
 #include "nsWindowWatcher.h"
 #include "nsWeakReference.h"
 
+#ifdef MOZ_WIDGET_ANDROID
+#include "AndroidBridge.h"
+#endif
+
 using namespace mozilla;
 using namespace mozilla::dom;
 using namespace mozilla::dom::workers;
@@ -498,6 +502,12 @@ public:
       return NS_OK;
     }
 
+#ifdef MOZ_WIDGET_ANDROID
+    // This fires an intent that will start launching Fennec and foreground it,
+    // if necessary.
+    java::GeckoAppShell::OpenWindowForNotification();
+#endif
+
     nsCOMPtr<nsPIDOMWindowOuter> window;
     nsresult rv = OpenWindow(getter_AddRefs(window));
     if (NS_SUCCEEDED(rv)) {
@@ -550,6 +560,41 @@ public:
       MOZ_ASSERT(NS_SUCCEEDED(rv));
       return NS_OK;
     }
+#ifdef MOZ_WIDGET_ANDROID
+    else if (rv == NS_ERROR_NOT_AVAILABLE) {
+      // We couldn't get a browser window, so Fennec must not be running.
+      // Send an Intent to launch Fennec and wait for "BrowserChrome:Ready"
+      // to try opening a window again.
+      nsCOMPtr<nsIObserverService> os = services::GetObserverService();
+      NS_ENSURE_STATE(os);
+
+      WorkerPrivate* workerPrivate = mPromiseProxy->GetWorkerPrivate();
+      MOZ_ASSERT(workerPrivate);
+
+      RefPtr<ServiceWorkerManager> swm = ServiceWorkerManager::GetInstance();
+      MOZ_ASSERT(swm);
+
+      nsCOMPtr<nsIPrincipal> principal = workerPrivate->GetPrincipal();
+      MOZ_ASSERT(principal);
+
+      RefPtr<ServiceWorkerRegistrationInfo> registration =
+        swm->GetRegistration(principal, NS_ConvertUTF16toUTF8(mScope));
+      if (NS_WARN_IF(!registration)) {
+        return NS_ERROR_FAILURE;
+      }
+
+      RefPtr<ServiceWorkerInfo> serviceWorkerInfo =
+        registration->GetServiceWorkerInfoById(workerPrivate->ServiceWorkerID());
+      if (NS_WARN_IF(!serviceWorkerInfo)) {
+        return NS_ERROR_FAILURE;
+      }
+
+      os->AddObserver(static_cast<nsIObserver*>(serviceWorkerInfo->WorkerPrivate()),
+                      "BrowserChrome:Ready", true);
+      serviceWorkerInfo->WorkerPrivate()->AddPendingWindow(this);
+      return NS_OK;
+    }
+#endif
 
     RefPtr<ResolveOpenWindowRunnable> resolveRunnable =
       new ResolveOpenWindowRunnable(mPromiseProxy, nullptr, rv);
@@ -627,7 +672,7 @@ private:
       // It is possible to be running without a browser window on Mac OS, so
       // we need to open a new chrome window.
       // TODO(catalinb): open new chrome window. Bug 1218080
-      return NS_ERROR_FAILURE;
+      return NS_ERROR_NOT_AVAILABLE;
     }
 
     nsCOMPtr<nsIDOMChromeWindow> chromeWin = do_QueryInterface(browserWindow);
@@ -758,7 +803,7 @@ ServiceWorkerClients::OpenWindow(const nsAString& aUrl,
   mWorkerScope->GetScope(scope);
 
   RefPtr<OpenWindowRunnable> r = new OpenWindowRunnable(promiseProxy,
-                                                          aUrl, scope);
+                                                        aUrl, scope);
   MOZ_ALWAYS_SUCCEEDS(workerPrivate->DispatchToMainThread(r.forget()));
 
   return promise.forget();
diff --git a/dom/workers/ServiceWorkerPrivate.cpp b/dom/workers/ServiceWorkerPrivate.cpp
index 15d9d09d8903..baac47985eb0 100644
--- a/dom/workers/ServiceWorkerPrivate.cpp
+++ b/dom/workers/ServiceWorkerPrivate.cpp
@@ -42,6 +42,7 @@ NS_IMPL_CYCLE_COLLECTION(ServiceWorkerPrivate, mSupportsArray)
 
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ServiceWorkerPrivate)
   NS_INTERFACE_MAP_ENTRY(nsISupports)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIObserver)
 NS_INTERFACE_MAP_END
 
 // Tracks the "dom.disable_open_click_delay" preference.  Modified on main
@@ -2012,4 +2013,36 @@ ServiceWorkerPrivate::CreateEventKeepAliveToken()
   return ref.forget();
 }
 
+void
+ServiceWorkerPrivate::AddPendingWindow(Runnable* aPendingWindow)
+{
+  AssertIsOnMainThread();
+  pendingWindows.AppendElement(aPendingWindow);
+}
+
+nsresult
+ServiceWorkerPrivate::Observe(nsISupports* aSubject, const char* aTopic, const char16_t* aData)
+{
+  AssertIsOnMainThread();
+
+  nsCString topic(aTopic);
+  if (!topic.Equals(NS_LITERAL_CSTRING("BrowserChrome:Ready"))) {
+    MOZ_ASSERT(false, "Unexpected topic.");
+    return NS_ERROR_FAILURE;
+  }
+
+  nsCOMPtr<nsIObserverService> os = services::GetObserverService();
+  NS_ENSURE_STATE(os);
+  os->RemoveObserver(static_cast<nsIObserver*>(this), "BrowserChrome:Ready");
+
+  size_t len = pendingWindows.Length();
+  for (int i = len-1; i >= 0; i--) {
+    RefPtr<Runnable> runnable = pendingWindows[i];
+    MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(runnable));
+    pendingWindows.RemoveElementAt(i);
+  }
+
+  return NS_OK;
+}
+
 END_WORKERS_NAMESPACE
diff --git a/dom/workers/ServiceWorkerPrivate.h b/dom/workers/ServiceWorkerPrivate.h
index 127c2ee2e63d..16b1c436941b 100644
--- a/dom/workers/ServiceWorkerPrivate.h
+++ b/dom/workers/ServiceWorkerPrivate.h
@@ -62,13 +62,14 @@ public:
 // with an appropriate reason before any runnable is dispatched to the worker.
 // If the event is extendable then the runnable should inherit
 // ExtendableEventWorkerRunnable.
-class ServiceWorkerPrivate final : public nsISupports
+class ServiceWorkerPrivate final : public nsIObserver
 {
   friend class KeepAliveToken;
 
 public:
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
   NS_DECL_CYCLE_COLLECTION_CLASS(ServiceWorkerPrivate)
+  NS_DECL_NSIOBSERVER
 
   explicit ServiceWorkerPrivate(ServiceWorkerInfo* aInfo);
 
@@ -149,6 +150,9 @@ public:
   bool
   IsIdle() const;
 
+  void
+  AddPendingWindow(Runnable* aPendingWindow);
+
 private:
   enum WakeUpReason {
     FetchEvent = 0,
@@ -221,6 +225,8 @@ private:
   // Array of function event worker runnables that are pending due to
   // the worker activating.  Main thread only.
   nsTArray<RefPtr<WorkerRunnable>> mPendingFunctionalEvents;
+
+  nsTArray<Runnable*> pendingWindows;
 };
 
 } // namespace workers
diff --git a/mobile/android/chrome/content/browser.js b/mobile/android/chrome/content/browser.js
index 7e2b9f131392..a2d2d17b41be 100644
--- a/mobile/android/chrome/content/browser.js
+++ b/mobile/android/chrome/content/browser.js
@@ -353,6 +353,7 @@ var BrowserApp = {
   startup: function startup() {
     window.QueryInterface(Ci.nsIDOMChromeWindow).browserDOMWindow = new nsBrowserAccess();
     dump("zerdatime " + Date.now() + " - browser chrome startup finished.");
+    Services.obs.notifyObservers(this.browser, "BrowserChrome:Ready", null);
 
     this.deck = document.getElementById("browsers");
 
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java
index de70089a4263..0a98f34e279e 100644
--- a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java
@@ -319,6 +319,15 @@ public class GeckoAppShell
         CRASH_HANDLER.uncaughtException(null, e);
     }
 
+    @WrapForJNI
+    public static void openWindowForNotification() {
+        Intent intent = new Intent(Intent.ACTION_MAIN);
+        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
+        intent.setClassName(AppConstants.ANDROID_PACKAGE_NAME, AppConstants.MOZ_ANDROID_BROWSER_INTENT_CLASS);
+
+        getApplicationContext().startActivity(intent);
+    }
+
     private static float getLocationAccuracy(Location location) {
         float radius = location.getAccuracy();
         return (location.hasAccuracy() && radius > 0) ? radius : 1001;
diff --git a/widget/android/GeneratedJNIWrappers.cpp b/widget/android/GeneratedJNIWrappers.cpp
index 1982a51b021c..5970ec683f85 100644
--- a/widget/android/GeneratedJNIWrappers.cpp
+++ b/widget/android/GeneratedJNIWrappers.cpp
@@ -537,6 +537,14 @@ auto GeckoAppShell::OpenUriExternal(mozilla::jni::String::Param a0, mozilla::jni
     return mozilla::jni::Method<OpenUriExternal_t>::Call(GeckoAppShell::Context(), nullptr, a0, a1, a2, a3, a4, a5);
 }
 
+constexpr char GeckoAppShell::OpenWindowForNotification_t::name[];
+constexpr char GeckoAppShell::OpenWindowForNotification_t::signature[];
+
+auto GeckoAppShell::OpenWindowForNotification() -> void
+{
+    return mozilla::jni::Method<OpenWindowForNotification_t>::Call(GeckoAppShell::Context(), nullptr);
+}
+
 constexpr char GeckoAppShell::PerformHapticFeedback_t::name[];
 constexpr char GeckoAppShell::PerformHapticFeedback_t::signature[];
 
diff --git a/widget/android/GeneratedJNIWrappers.h b/widget/android/GeneratedJNIWrappers.h
index 6662b7927450..a098e604f40e 100644
--- a/widget/android/GeneratedJNIWrappers.h
+++ b/widget/android/GeneratedJNIWrappers.h
@@ -1452,6 +1452,25 @@ public:
 
     static auto OpenUriExternal(mozilla::jni::String::Param, mozilla::jni::String::Param, mozilla::jni::String::Param, mozilla::jni::String::Param, mozilla::jni::String::Param, mozilla::jni::String::Param) -> bool;
 
+    struct OpenWindowForNotification_t {
+        typedef GeckoAppShell Owner;
+        typedef void ReturnType;
+        typedef void SetterType;
+        typedef mozilla::jni::Args<> Args;
+        static constexpr char name[] = "openWindowForNotification";
+        static constexpr char signature[] =
+                "()V";
+        static const bool isStatic = true;
+        static const mozilla::jni::ExceptionMode exceptionMode =
+                mozilla::jni::ExceptionMode::ABORT;
+        static const mozilla::jni::CallingThread callingThread =
+                mozilla::jni::CallingThread::ANY;
+        static const mozilla::jni::DispatchTarget dispatchTarget =
+                mozilla::jni::DispatchTarget::CURRENT;
+    };
+
+    static auto OpenWindowForNotification() -> void;
+
     struct PerformHapticFeedback_t {
         typedef GeckoAppShell Owner;
         typedef void ReturnType;