--- a/dom/html/HTMLMediaElement.cpp
+++ b/dom/html/HTMLMediaElement.cpp
@@ -2996,29 +2996,29 @@ void
 HTMLMediaElement::NotifyXPCOMShutdown()
 {
   ShutdownDecoder();
 }
 
 void
 HTMLMediaElement::Play(ErrorResult& aRv)
 {
+  if (!IsAllowedToPlay()) {
+    return;
+  }
+
   nsresult rv = PlayInternal();
   if (NS_FAILED(rv)) {
     aRv.Throw(rv);
   }
 }
 
 nsresult
 HTMLMediaElement::PlayInternal()
 {
-  if (!IsAllowedToPlay()) {
-    return NS_OK;
-  }
-
   // Play was not blocked so assume user interacted with the element.
   mHasUserInteraction = true;
 
   StopSuspendingAfterFirstFrame();
   SetPlayedOrSeeked(true);
 
   if (mNetworkState == nsIDOMHTMLMediaElement::NETWORK_EMPTY) {
     DoLoad();
@@ -3085,16 +3085,20 @@ HTMLMediaElement::PlayInternal()
     }
   }
 
   return NS_OK;
 }
 
 NS_IMETHODIMP HTMLMediaElement::Play()
 {
+  if (!IsAllowedToPlay()) {
+    return NS_OK;
+  }
+
   return PlayInternal();
 }
 
 HTMLMediaElement::WakeLockBoolWrapper&
 HTMLMediaElement::WakeLockBoolWrapper::operator=(bool val)
 {
   if (mValue == val) {
     return *this;
@@ -4941,16 +4945,20 @@ bool HTMLMediaElement::CanActivateAutopl
   if (!mPaused) {
     return false;
   }
 
   if (mPausedForInactiveDocumentOrChannel) {
     return false;
   }
 
+  if (!IsAllowedToPlay()) {
+    return false;
+  }
+
   bool hasData =
     (mDecoder && mReadyState >= nsIDOMHTMLMediaElement::HAVE_ENOUGH_DATA) ||
     mSrcStream || mMediaSource;
 
   return hasData;
 }
 
 void HTMLMediaElement::CheckAutoplayDataReady()
@@ -4965,19 +4973,17 @@ void HTMLMediaElement::CheckAutoplayData
   UpdateSrcMediaStreamPlaying();
   UpdateAudioChannelPlayingState();
 
   if (mDecoder) {
     SetPlayedOrSeeked(true);
     if (mCurrentPlayRangeStart == -1.0) {
       mCurrentPlayRangeStart = CurrentTime();
     }
-    if (!ShouldElementBePaused()) {
-      mDecoder->Play();
-    }
+    mDecoder->Play();
   } else if (mSrcStream) {
     SetPlayedOrSeeked(true);
   }
 
   // For blocked media, the event would be pending until it is resumed.
   DispatchAsyncEvent(NS_LITERAL_STRING("play"));
 
   DispatchAsyncEvent(NS_LITERAL_STRING("playing"));
@@ -5769,19 +5775,20 @@ HTMLMediaElement::IsPlayingThroughTheAud
   if (mSrcAttrStream) {
     return true;
   }
 
   return false;
 }
 
 void
-HTMLMediaElement::UpdateAudioChannelPlayingState()
-{
-  bool playingThroughTheAudioChannel = IsPlayingThroughTheAudioChannel();
+HTMLMediaElement::UpdateAudioChannelPlayingState(bool aForcePlaying)
+{
+  bool playingThroughTheAudioChannel =
+    aForcePlaying || IsPlayingThroughTheAudioChannel();
 
   if (playingThroughTheAudioChannel != mPlayingThroughTheAudioChannel) {
     mPlayingThroughTheAudioChannel = playingThroughTheAudioChannel;
     NotifyAudioChannelAgent(mPlayingThroughTheAudioChannel);
   }
 }
 
 void
@@ -5889,31 +5896,33 @@ HTMLMediaElement::ResumeFromAudioChannel
 
 void
 HTMLMediaElement::ResumeFromAudioChannelPaused(SuspendTypes aSuspend)
 {
   MOZ_ASSERT(mAudioChannelSuspended == nsISuspendedTypes::SUSPENDED_PAUSE ||
              mAudioChannelSuspended == nsISuspendedTypes::SUSPENDED_PAUSE_DISPOSABLE);
 
   SetAudioChannelSuspended(nsISuspendedTypes::NONE_SUSPENDED);
-  nsresult rv = PlayInternal();
+  nsresult rv = Play();
   if (NS_WARN_IF(NS_FAILED(rv))) {
     return;
   }
   DispatchAsyncEvent(NS_LITERAL_STRING("mozinterruptend"));
 }
 
 void
 HTMLMediaElement::ResumeFromAudioChannelBlocked()
 {
   MOZ_ASSERT(mAudioChannelSuspended == nsISuspendedTypes::SUSPENDED_BLOCK);
 
   SetAudioChannelSuspended(nsISuspendedTypes::NONE_SUSPENDED);
-  mPaused = false;
-  SuspendOrResumeElement(false /* resume */, false);
+  nsresult rv = Play();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
 }
 
 void
 HTMLMediaElement::PauseByAudioChannel(SuspendTypes aSuspend)
 {
   if (IsSuspendedByAudioChannel()) {
     return;
   }
@@ -5926,18 +5935,16 @@ HTMLMediaElement::PauseByAudioChannel(Su
 void
 HTMLMediaElement::BlockByAudioChannel()
 {
   if (IsSuspendedByAudioChannel()) {
     return;
   }
 
   SetAudioChannelSuspended(nsISuspendedTypes::SUSPENDED_BLOCK);
-  mPaused = true;
-  SuspendOrResumeElement(true /* suspend */, true /* pending event */);
 }
 
 void
 HTMLMediaElement::SetAudioChannelSuspended(SuspendTypes aSuspend)
 {
   if (mAudioChannelSuspended == aSuspend) {
     return;
   }
@@ -5974,25 +5981,42 @@ HTMLMediaElement::IsAllowedToPlay()
                                          static_cast<nsIContent*>(this),
                                          NS_LITERAL_STRING("MozAutoplayMediaBlocked"),
                                          false,
                                          false);
 #endif
     return false;
   }
 
-  // The MediaElement can't start playback until it's resumed by audio channel.
+  // The media element has already been paused or blocked, so it can't start
+  // playback again by script or user's intend until resuming by audio channel.
   if (mAudioChannelSuspended == nsISuspendedTypes::SUSPENDED_PAUSE ||
       mAudioChannelSuspended == nsISuspendedTypes::SUSPENDED_BLOCK) {
     return false;
   }
 
+  // If the tab hasn't been activated yet, the media element in that tab can't
+  // be playback now until the tab goes to foreground first time or user clicks
+  // the unblocking tab icon.
+  if (!IsTabActivated()) {
+    // Even we haven't start playing yet, we still need to notify the audio
+    // channe system because we need to receive the resume notification later.
+    UpdateAudioChannelPlayingState(true /* force to start */);
+    return false;
+  }
+
   return true;
 }
 
+bool
+HTMLMediaElement::IsTabActivated() const
+{
+  return !mAudioChannelAgent->ShouldBlockMedia();
+}
+
 static const char* VisibilityString(Visibility aVisibility) {
   switch(aVisibility) {
     case Visibility::UNTRACKED: {
       return "UNTRACKED";
     }
     case Visibility::APPROXIMATELY_NONVISIBLE: {
       return "APPROXIMATELY_NONVISIBLE";
     }
@@ -6494,21 +6518,16 @@ HTMLMediaElement::OpenUnsupportedMediaWi
                                        NS_LITERAL_STRING("OpenMediaWithExternalApp"),
                                        true,
                                        true);
 }
 
 bool
 HTMLMediaElement::ShouldElementBePaused()
 {
-  // The media in the non-visited page would be blocked.
-  if (mAudioChannelSuspended == nsISuspendedTypes::SUSPENDED_BLOCK) {
-    return true;
-  }
-
   // Bfcached page or inactive document.
   if (!IsActive()) {
     return true;
   }
 
   return false;
 }
 

--- a/dom/html/HTMLMediaElement.h
+++ b/dom/html/HTMLMediaElement.h
@@ -1200,17 +1200,17 @@ protected:
   // desired, and we'll seek to the sync point (keyframe and/or start of the
   // next block of audio samples) preceeding seek target.
   already_AddRefed<Promise> Seek(double aTime, SeekTarget::Type aSeekType, ErrorResult& aRv);
 
   // A method to check if we are playing through the AudioChannel.
   bool IsPlayingThroughTheAudioChannel() const;
 
   // Update the audio channel playing state
-  void UpdateAudioChannelPlayingState();
+  void UpdateAudioChannelPlayingState(bool aForcePlaying = false);
 
   // Adds to the element's list of pending text tracks each text track
   // in the element's list of text tracks whose text track mode is not disabled
   // and whose text track readiness state is loading.
   void PopulatePendingTextTrackList();
 
   // Gets a reference to the MediaElement's TextTrackManager. If the
   // MediaElement doesn't yet have one then it will create it.
@@ -1257,18 +1257,23 @@ protected:
 
   void ResumeFromAudioChannel();
   void ResumeFromAudioChannelPaused(SuspendTypes aSuspend);
   void ResumeFromAudioChannelBlocked();
 
   bool IsSuspendedByAudioChannel() const;
   void SetAudioChannelSuspended(SuspendTypes aSuspend);
 
+  // A method to check whether the media element is allowed to start playback.
   bool IsAllowedToPlay();
 
+  // True if the tab which media element belongs to has been to foreground at
+  // least once or activated by manually clicking the unblocking tab icon.
+  bool IsTabActivated() const;
+
   bool IsAudible() const;
   bool HaveFailedWithSourceNotSupportedError() const;
 
   void OpenUnsupportedMediaWithExtenalAppIfNeeded();
 
   // It's used for fennec only, send the notification when the user resumes the
   // media which was paused by media control.
   void MaybeNotifyMediaResumed(SuspendTypes aSuspend);