--- a/dom/base/nsGkAtomList.h
+++ b/dom/base/nsGkAtomList.h
@@ -817,16 +817,17 @@ GK_ATOM(onmozfullscreenerror, "onmozfull
 GK_ATOM(onmozpointerlockchange, "onmozpointerlockchange")
 GK_ATOM(onmozpointerlockerror, "onmozpointerlockerror")
 GK_ATOM(onmoztimechange, "onmoztimechange")
 GK_ATOM(onMozMousePixelScroll, "onMozMousePixelScroll")
 GK_ATOM(onMozScrolledAreaChanged, "onMozScrolledAreaChanged")
 GK_ATOM(onmoznetworkupload, "onmoznetworkupload")
 GK_ATOM(onmoznetworkdownload, "onmoznetworkdownload")
 GK_ATOM(onnewrdsgroup, "onnewrdsgroup")
+GK_ATOM(onnotificationclick, "onnotificationclick")
 GK_ATOM(onnoupdate, "onnoupdate")
 GK_ATOM(onobsolete, "onobsolete")
 GK_ATOM(ononline, "ononline")
 GK_ATOM(onoffline, "onoffline")
 GK_ATOM(onopen, "onopen")
 GK_ATOM(onotastatuschange, "onotastatuschange")
 GK_ATOM(onoverflow, "onoverflow")
 GK_ATOM(onoverflowchanged, "onoverflowchanged")

--- a/dom/bindings/Bindings.conf
+++ b/dom/bindings/Bindings.conf
@@ -860,16 +860,24 @@ DOMInterfaces = {
 'NodeIterator': {
     'wrapperCache': False,
 },
 
 'NodeList': {
     'nativeType': 'nsINodeList',
 },
 
+'NotificationEvent': {
+    'headerFile': 'mozilla/dom/NotificationEvent.h',
+    'nativeType': 'mozilla::dom::workers::NotificationEvent',
+    'binaryNames': {
+        'notification': 'notification_'
+    }
+},
+
 'OfflineAudioContext': {
     'nativeType': 'mozilla::dom::AudioContext',
 },
 
 'OfflineResourceList': {
     'nativeType': 'nsDOMOfflineResourceList',
 },
 

--- a/dom/notification/Notification.cpp
+++ b/dom/notification/Notification.cpp
@@ -1409,20 +1409,17 @@ Notification::Get(const GlobalObject& aG
   }
 
   nsRefPtr<Promise> promise = Promise::Create(global, aRv);
   if (aRv.Failed()) {
     return nullptr;
   }
   nsCOMPtr<nsINotificationStorageCallback> callback =
     new NotificationStorageCallback(aGlobal, window, promise);
-  nsString tag = aFilter.mTag.WasPassed() ?
-                 aFilter.mTag.Value() :
-                 EmptyString();
-  aRv = notificationStorage->Get(origin, tag, callback);
+  aRv = notificationStorage->Get(origin, aFilter.mTag, callback);
   if (aRv.Failed()) {
     return nullptr;
   }
 
   return promise.forget();
 }
 
 JSObject*

--- a/dom/webidl/Notification.webidl
+++ b/dom/webidl/Notification.webidl
@@ -63,17 +63,17 @@ dictionary NotificationOptions {
   DOMString body = "";
   DOMString tag = "";
   DOMString icon = "";
   any data = null;
   NotificationBehavior mozbehavior = null;
 };
 
 dictionary GetNotificationOptions {
-  DOMString tag;
+  DOMString tag = "";
 };
 
 dictionary NotificationBehavior {
   boolean noscreen = false;
   boolean noclear = false;
   boolean showOnlyOnce = false;
   DOMString soundFile = "";
   sequence<unsigned long> vibrationPattern;
@@ -88,8 +88,12 @@ enum NotificationPermission {
 callback NotificationPermissionCallback = void (NotificationPermission permission);
 
 enum NotificationDirection {
   "auto",
   "ltr",
   "rtl"
 };
 
+partial interface ServiceWorkerRegistration {
+  Promise<void> showNotification(DOMString title, optional NotificationOptions options);
+  Promise<sequence<Notification>> getNotifications(optional GetNotificationOptions filter);
+};

--- a/dom/webidl/ServiceWorker.webidl
+++ b/dom/webidl/ServiceWorker.webidl
@@ -7,17 +7,17 @@
  * http://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html#service-worker-obj
  *
  */
 
 // Still unclear what should be subclassed.
 // https://github.com/slightlyoff/ServiceWorker/issues/189
 [Func="mozilla::dom::workers::ServiceWorkerVisible",
  // FIXME(nsm): Bug 1113522. This is exposed to satisfy webidl constraints, but it won't actually work.
- Exposed=(Worker,Window)]
+ Exposed=(Window,Worker)]
 interface ServiceWorker : EventTarget {
   readonly attribute USVString scriptURL;
   readonly attribute ServiceWorkerState state;
 
   attribute EventHandler onstatechange;
 
   // FIXME(catalinb): Should inherit this from Worker.
   [Throws]

--- a/dom/workers/ServiceWorkerRegistration.cpp
+++ b/dom/workers/ServiceWorkerRegistration.cpp
@@ -583,16 +583,33 @@ ServiceWorkerRegistrationMainThread::Unr
   aRv = swm->Unregister(documentPrincipal, cb, scope);
   if (aRv.Failed()) {
     return nullptr;
   }
 
   return promise.forget();
 }
 
+// Notification API extension.
+already_AddRefed<Promise>
+ServiceWorkerRegistrationMainThread::ShowNotification(JSContext* aCx,
+                                                      const nsAString& aTitle,
+                                                      const NotificationOptions& aOptions)
+{
+  MOZ_ASSERT(false);
+  return nullptr;
+}
+
+already_AddRefed<Promise>
+ServiceWorkerRegistrationMainThread::GetNotifications(const GetNotificationOptions& aOptions)
+{
+  MOZ_ASSERT(false);
+  return nullptr;
+}
+
 already_AddRefed<PushManager>
 ServiceWorkerRegistrationMainThread::GetPushManager(ErrorResult& aRv)
 {
   AssertIsOnMainThread();
 
 #ifdef MOZ_SIMPLEPUSH
   return nullptr;
 #else
@@ -986,10 +1003,28 @@ WorkerListener::UpdateFound()
     nsRefPtr<FireUpdateFoundRunnable> r =
       new FireUpdateFoundRunnable(mWorkerPrivate, this);
     AutoJSAPI jsapi;
     jsapi.Init();
     if (NS_WARN_IF(!r->Dispatch(jsapi.cx()))) {
     }
   }
 }
+
+// Notification API extension.
+already_AddRefed<Promise>
+ServiceWorkerRegistrationWorkerThread::ShowNotification(JSContext* aCx,
+                                                        const nsAString& aTitle,
+                                                        const NotificationOptions& aOptions)
+{
+  MOZ_ASSERT(false);
+  return nullptr;
+}
+
+already_AddRefed<Promise>
+ServiceWorkerRegistrationWorkerThread::GetNotifications(const GetNotificationOptions& aOptions)
+{
+  MOZ_ASSERT(false);
+  return nullptr;
+}
+
 } // dom namespace
 } // mozilla namespace

--- a/dom/workers/ServiceWorkerRegistration.h
+++ b/dom/workers/ServiceWorkerRegistration.h
@@ -7,16 +7,19 @@
 #ifndef mozilla_dom_ServiceWorkerRegistration_h
 #define mozilla_dom_ServiceWorkerRegistration_h
 
 #include "mozilla/DOMEventTargetHelper.h"
 #include "mozilla/dom/ServiceWorkerBinding.h"
 #include "mozilla/dom/ServiceWorkerCommon.h"
 #include "mozilla/dom/workers/bindings/WorkerFeature.h"
 
+// Support for Notification API extension.
+#include "mozilla/dom/NotificationBinding.h"
+
 class nsPIDOMWindow;
 
 namespace mozilla {
 namespace dom {
 
 class Promise;
 class PushManager;
 class WorkerListener;
@@ -106,16 +109,25 @@ public:
   Update();
 
   already_AddRefed<Promise>
   Unregister(ErrorResult& aRv);
 
   JSObject*
   WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override;
 
+  // Partial interface from Notification API.
+  already_AddRefed<Promise>
+  ShowNotification(JSContext* aCx,
+                   const nsAString& aTitle,
+                   const NotificationOptions& aOptions);
+
+  already_AddRefed<Promise>
+  GetNotifications(const GetNotificationOptions& aOptions);
+
   already_AddRefed<workers::ServiceWorker>
   GetInstalling() override;
 
   already_AddRefed<workers::ServiceWorker>
   GetWaiting() override;
 
   already_AddRefed<workers::ServiceWorker>
   GetActive() override;
@@ -185,16 +197,25 @@ public:
   Update();
 
   already_AddRefed<Promise>
   Unregister(ErrorResult& aRv);
 
   JSObject*
   WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override;
 
+  // Partial interface from Notification API.
+  already_AddRefed<Promise>
+  ShowNotification(JSContext* aCx,
+                   const nsAString& aTitle,
+                   const NotificationOptions& aOptions);
+
+  already_AddRefed<Promise>
+  GetNotifications(const GetNotificationOptions& aOptions);
+
   already_AddRefed<workers::ServiceWorker>
   GetInstalling() override;
 
   already_AddRefed<workers::ServiceWorker>
   GetWaiting() override;
 
   already_AddRefed<workers::ServiceWorker>
   GetActive() override;

--- a/dom/workers/WorkerScope.h
+++ b/dom/workers/WorkerScope.h
@@ -203,16 +203,17 @@ class ServiceWorkerGlobalScope final : p
   nsRefPtr<ServiceWorkerRegistrationWorkerThread> mRegistration;
 
   ~ServiceWorkerGlobalScope();
 
 public:
   NS_DECL_ISUPPORTS_INHERITED
   NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(ServiceWorkerGlobalScope,
                                            WorkerGlobalScope)
+  IMPL_EVENT_HANDLER(notificationclick)
 
   ServiceWorkerGlobalScope(WorkerPrivate* aWorkerPrivate, const nsACString& aScope);
 
   virtual bool
   WrapGlobalObject(JSContext* aCx,
                    JS::MutableHandle<JSObject*> aReflector) override;
 
   static bool