diff --git a/dom/power/PowerManagerService.cpp b/dom/power/PowerManagerService.cpp
index 7716c093ba8b..d622c2ad457d 100644
--- a/dom/power/PowerManagerService.cpp
+++ b/dom/power/PowerManagerService.cpp
@@ -139,7 +139,7 @@ PowerManagerService::NewWakeLock(const nsAString& aTopic,
 NS_IMETHODIMP
 PowerManagerService::NewWakeLock(const nsAString &aTopic,
                                  mozIDOMWindow *aWindow,
-                                 nsISupports **aWakeLock)
+                                 nsIWakeLock **aWakeLock)
 {
   mozilla::ErrorResult rv;
   RefPtr<WakeLock> wakelock =
@@ -148,8 +148,7 @@ PowerManagerService::NewWakeLock(const nsAString &aTopic,
     return rv.StealNSResult();
   }
 
-  nsCOMPtr<nsIDOMEventListener> eventListener = wakelock.get();
-  eventListener.forget(aWakeLock);
+  wakelock.forget(aWakeLock);
   return NS_OK;
 }
 
diff --git a/dom/power/WakeLock.cpp b/dom/power/WakeLock.cpp
index 50746b9973e7..3d99edf5726d 100644
--- a/dom/power/WakeLock.cpp
+++ b/dom/power/WakeLock.cpp
@@ -25,6 +25,7 @@ NS_INTERFACE_MAP_BEGIN(WakeLock)
   NS_INTERFACE_MAP_ENTRY(nsIDOMEventListener)
   NS_INTERFACE_MAP_ENTRY(nsIObserver)
   NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
+  NS_INTERFACE_MAP_ENTRY(nsIWakeLock)
 NS_INTERFACE_MAP_END
 
 NS_IMPL_ADDREF(WakeLock)
@@ -258,6 +259,14 @@ WakeLock::HandleEvent(Event *aEvent)
   return NS_OK;
 }
 
+NS_IMETHODIMP
+WakeLock::Unlock()
+{
+  ErrorResult error;
+  Unlock(error);
+  return error.StealNSResult();
+}
+
 nsPIDOMWindowInner*
 WakeLock::GetParentObject() const
 {
diff --git a/dom/power/WakeLock.h b/dom/power/WakeLock.h
index dd31e6c7f14a..5f17c41e7781 100644
--- a/dom/power/WakeLock.h
+++ b/dom/power/WakeLock.h
@@ -10,6 +10,7 @@
 #include "nsCOMPtr.h"
 #include "nsIDOMEventListener.h"
 #include "nsIObserver.h"
+#include "nsIWakeLock.h"
 #include "nsString.h"
 #include "nsWeakReference.h"
 #include "nsWrapperCache.h"
@@ -26,10 +27,12 @@ class WakeLock final
   : public nsIDOMEventListener
   , public nsIObserver
   , public nsSupportsWeakReference
+  , public nsIWakeLock
 {
 public:
   NS_DECL_NSIDOMEVENTLISTENER
   NS_DECL_NSIOBSERVER
+  NS_DECL_NSIWAKELOCK
 
   NS_DECL_ISUPPORTS
 
diff --git a/dom/power/moz.build b/dom/power/moz.build
index 3d391ec56ad3..cc949920fe21 100644
--- a/dom/power/moz.build
+++ b/dom/power/moz.build
@@ -10,6 +10,7 @@ with Files("**"):
 XPIDL_SOURCES += [
     'nsIDOMWakeLockListener.idl',
     'nsIPowerManagerService.idl',
+    'nsIWakeLock.idl',
 ]
 
 XPIDL_MODULE = 'dom_power'
diff --git a/dom/power/nsIPowerManagerService.idl b/dom/power/nsIPowerManagerService.idl
index 4626c8435460..49d8e3f693ad 100644
--- a/dom/power/nsIPowerManagerService.idl
+++ b/dom/power/nsIPowerManagerService.idl
@@ -12,6 +12,7 @@
 
 interface nsIDOMMozWakeLockListener;
 interface mozIDOMWindow;
+interface nsIWakeLock;
 
 /**
  * For use with non-content code.
@@ -28,5 +29,5 @@ interface nsIPowerManagerService : nsISupports
    * A wake lock without associated window, e.g. used in chrome, is
    * always considered invisible.
    */
-  nsISupports newWakeLock(in AString aTopic, [optional] in mozIDOMWindow aWindow);
+  nsIWakeLock newWakeLock(in AString aTopic, [optional] in mozIDOMWindow aWindow);
 };
diff --git a/dom/power/nsIWakeLock.idl b/dom/power/nsIWakeLock.idl
new file mode 100644
index 000000000000..5ebc15810954
--- /dev/null
+++ b/dom/power/nsIWakeLock.idl
@@ -0,0 +1,12 @@
+/* -*- Mode: C++; tab-width: 40; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+[scriptable, builtinclass, uuid(e27e57ce-fa63-4035-b9ef-27c5dc0cc3ae)]
+interface nsIWakeLock : nsISupports
+{
+  void unlock();
+};
diff --git a/dom/tests/browser/browser.ini b/dom/tests/browser/browser.ini
index 32f275b8f750..bf9e5cb8ac2c 100644
--- a/dom/tests/browser/browser.ini
+++ b/dom/tests/browser/browser.ini
@@ -81,3 +81,4 @@ support-files =
 [browser_noopener_null_uri.js]
 [browser_test_performance_metrics_off.js]
 skip-if = verify
+[browser_wakelock.js]
diff --git a/dom/tests/browser/browser_wakelock.js b/dom/tests/browser/browser_wakelock.js
new file mode 100644
index 000000000000..2b1d81230b2a
--- /dev/null
+++ b/dom/tests/browser/browser_wakelock.js
@@ -0,0 +1,27 @@
+/**
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+"use strict";
+
+add_task(async () => {
+  info("creating test window");
+  let win = await BrowserTestUtils.openNewBrowserWindow();
+
+  const pm = Cc["@mozilla.org/power/powermanagerservice;1"]
+             .getService(Ci.nsIPowerManagerService);
+
+  is(pm.getWakeLockState("screen"), "unlocked", "Wakelock should be unlocked state");
+
+  info("aquiring wakelock");
+  const wakelock = pm.newWakeLock("screen", win);
+  isnot(pm.getWakeLockState("screen"), "unlocked", "Wakelock shouldn't be unlocked state");
+
+  info("releasing wakelock");
+  wakelock.unlock();
+  is(pm.getWakeLockState("screen"), "unlocked", "Wakelock should be unlocked state");
+
+  info("closing test window");
+  await BrowserTestUtils.closeWindow(win);
+});