--- a/dom/html/HTMLMediaElement.cpp
+++ b/dom/html/HTMLMediaElement.cpp
@@ -4992,16 +4992,18 @@ void HTMLMediaElement::CheckAutoplayData
       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"));
 }
 
 bool HTMLMediaElement::IsActive() const
 {
   nsIDocument* ownerDoc = OwnerDoc();
   return ownerDoc && ownerDoc->IsActive() && ownerDoc->IsVisible();
 }