--- a/dom/html/HTMLMediaElement.cpp
+++ b/dom/html/HTMLMediaElement.cpp
@@ -2877,17 +2877,16 @@ HTMLMediaElement::HTMLMediaElement(alrea
     mAllowCasting(false),
     mIsCasting(false),
     mAudioCaptured(false),
     mAudioCapturedByWindow(false),
     mPlayingBeforeSeek(false),
     mPlayingThroughTheAudioChannelBeforeSeek(false),
     mPausedForInactiveDocumentOrChannel(false),
     mEventDeliveryPaused(false),
-    mWaitingFired(false),
     mIsRunningLoadMethod(false),
     mIsDoingExplicitLoad(false),
     mIsLoadingFromSourceChildren(false),
     mDelayingLoadEvent(false),
     mIsRunningSelectResource(false),
     mHaveQueuedSelectResource(false),
     mSuspendedAfterFirstFrame(false),
     mAllowSuspendAfterFirstFrame(true),
@@ -4770,21 +4769,16 @@ HTMLMediaElement::UpdateReadyStateIntern
   }
 
   if (nextFrameStatus != MediaDecoderOwner::NEXT_FRAME_AVAILABLE) {
     LOG(LogLevel::Debug, ("MediaElement %p UpdateReadyStateInternal() "
                           "Next frame not available", this));
     if (mFirstFrameLoaded) {
       ChangeReadyState(nsIDOMHTMLMediaElement::HAVE_CURRENT_DATA);
     }
-    if (!mWaitingFired && nextFrameStatus == MediaDecoderOwner::NEXT_FRAME_UNAVAILABLE_BUFFERING) {
-      FireTimeUpdate(false);
-      DispatchAsyncEvent(NS_LITERAL_STRING("waiting"));
-      mWaitingFired = true;
-    }
     return;
   }
 
   if (!mFirstFrameLoaded) {
     // We haven't yet loaded the first frame, making us unable to determine
     // if we have enough valid data at the present stage.
     return;
   }
@@ -4833,32 +4827,43 @@ void HTMLMediaElement::ChangeReadyState(
     return;
   }
 
   LOG(LogLevel::Debug, ("%p Ready state changed to %s", this, gReadyStateToString[aState]));
 
   UpdateAudioChannelPlayingState();
 
   // Handle raising of "waiting" event during seek (see 4.8.10.9)
+  // or
+  // 4.8.12.7 Ready states:
+  // "If the previous ready state was HAVE_FUTURE_DATA or more, and the new
+  // ready state is HAVE_CURRENT_DATA or less
+  // If the media element was potentially playing before its readyState
+  // attribute changed to a value lower than HAVE_FUTURE_DATA, and the element
+  // has not ended playback, and playback has not stopped due to errors,
+  // paused for user interaction, or paused for in-band content, the user agent
+  // must queue a task to fire a simple event named timeupdate at the element,
+  // and queue a task to fire a simple event named waiting at the element."
   if (mPlayingBeforeSeek &&
       mReadyState < nsIDOMHTMLMediaElement::HAVE_FUTURE_DATA) {
     DispatchAsyncEvent(NS_LITERAL_STRING("waiting"));
+  } else if (oldState >= nsIDOMHTMLMediaElement::HAVE_FUTURE_DATA &&
+             mReadyState < nsIDOMHTMLMediaElement::HAVE_FUTURE_DATA &&
+             !Paused() && !Ended() && !mError) {
+    FireTimeUpdate(false);
+    DispatchAsyncEvent(NS_LITERAL_STRING("waiting"));
   }
 
   if (oldState < nsIDOMHTMLMediaElement::HAVE_CURRENT_DATA &&
       mReadyState >= nsIDOMHTMLMediaElement::HAVE_CURRENT_DATA &&
       !mLoadedDataFired) {
     DispatchAsyncEvent(NS_LITERAL_STRING("loadeddata"));
     mLoadedDataFired = true;
   }
 
-  if (mReadyState == nsIDOMHTMLMediaElement::HAVE_CURRENT_DATA) {
-    mWaitingFired = false;
-  }
-
   if (oldState < nsIDOMHTMLMediaElement::HAVE_FUTURE_DATA &&
       mReadyState >= nsIDOMHTMLMediaElement::HAVE_FUTURE_DATA) {
     DispatchAsyncEvent(NS_LITERAL_STRING("canplay"));
   }
 
   CheckAutoplayDataReady();
 
   if (oldState < nsIDOMHTMLMediaElement::HAVE_FUTURE_DATA &&

--- a/dom/html/HTMLMediaElement.h
+++ b/dom/html/HTMLMediaElement.h
@@ -1511,20 +1511,16 @@ protected:
 
   // True iff this element is paused because the document is inactive or has
   // been suspended by the audio channel service.
   bool mPausedForInactiveDocumentOrChannel;
 
   // True iff event delivery is suspended (mPausedForInactiveDocumentOrChannel must also be true).
   bool mEventDeliveryPaused;
 
-  // True if we've reported a "waiting" event since the last
-  // readyState change to HAVE_CURRENT_DATA.
-  bool mWaitingFired;
-
   // True if we're running the "load()" method.
   bool mIsRunningLoadMethod;
 
   // True if we're running or waiting to run queued tasks due to an explicit
   // call to "load()".
   bool mIsDoingExplicitLoad;
 
   // True if we're loading the resource from the child source elements.