diff --git a/dom/media/MediaStreamGraph.cpp b/dom/media/MediaStreamGraph.cpp
index b0d0de1e5bcc..47034d303d31 100644
--- a/dom/media/MediaStreamGraph.cpp
+++ b/dom/media/MediaStreamGraph.cpp
@@ -23,6 +23,7 @@
 #include "AudioNodeStream.h"
 #include "AudioNodeExternalInputStream.h"
 #include "MediaStreamListener.h"
+#include "MediaStreamVideoSink.h"
 #include "mozilla/dom/AudioContextBinding.h"
 #include "mozilla/media/MediaUtils.h"
 #include <algorithm>
@@ -2287,6 +2288,8 @@ MediaStream::AddVideoOutputImpl(already_AddRefed<MediaStreamVideoSink> aSink,
    TrackBound<MediaStreamVideoSink>* l = mVideoOutputs.AppendElement();
    l->mListener = sink;
    l->mTrackID = aID;
+
+   AddDirectTrackListenerImpl(sink.forget(), aID);
 }
 
 void
@@ -2307,6 +2310,8 @@ MediaStream::RemoveVideoOutputImpl(MediaStreamVideoSink* aSink,
       mVideoOutputs.RemoveElementAt(i);
     }
   }
+
+  RemoveDirectTrackListenerImpl(aSink, aID);
 }
 
 void
@@ -2969,6 +2974,15 @@ SourceMediaStream::AddDirectTrackListenerImpl(already_AddRefed<DirectMediaStream
       isVideo = data->mData->GetType() == MediaSegment::VIDEO;
     }
     if (found && (isAudio || isVideo)) {
+      for (auto entry : mDirectTrackListeners) {
+        if (entry.mListener == listener &&
+            (entry.mTrackID == TRACK_ANY || entry.mTrackID == aTrackID)) {
+          listener->NotifyDirectListenerInstalled(
+            DirectMediaStreamTrackListener::InstallationResult::ALREADY_EXISTS);
+          return;
+        }
+      }
+
       TrackBound<DirectMediaStreamTrackListener>* sourceListener =
         mDirectTrackListeners.AppendElement();
       sourceListener->mListener = listener;
diff --git a/dom/media/MediaStreamListener.h b/dom/media/MediaStreamListener.h
index 2036fa9be3da..9e6f9c6094f5 100644
--- a/dom/media/MediaStreamListener.h
+++ b/dom/media/MediaStreamListener.h
@@ -14,6 +14,7 @@ namespace mozilla {
 class AudioSegment;
 class MediaStream;
 class MediaStreamGraph;
+class MediaStreamVideoSink;
 class VideoSegment;
 
 enum MediaStreamGraphEvent : uint32_t {
@@ -245,6 +246,9 @@ public:
    * STREAM_NOT_SUPPORTED
    *    While looking for the data source of this track, we found a MediaStream
    *    that is not a SourceMediaStream or a TrackUnionStream.
+   * ALREADY_EXIST
+   *    This DirectMediaStreamTrackListener already exists in the
+   *    SourceMediaStream.
    * SUCCESS
    *    Installation was successful and this listener will start receiving
    *    NotifyRealtimeData on the next AppendToTrack().
@@ -253,11 +257,14 @@ public:
     TRACK_NOT_FOUND_AT_SOURCE,
     TRACK_TYPE_NOT_SUPPORTED,
     STREAM_NOT_SUPPORTED,
+    ALREADY_EXISTS,
     SUCCESS
   };
   virtual void NotifyDirectListenerInstalled(InstallationResult aResult) {}
   virtual void NotifyDirectListenerUninstalled() {}
 
+  virtual MediaStreamVideoSink* AsMediaStreamVideoSink() { return nullptr; }
+
 protected:
   virtual ~DirectMediaStreamTrackListener() {}
 
diff --git a/dom/media/MediaStreamVideoSink.h b/dom/media/MediaStreamVideoSink.h
index 344f99de7b13..0a4fd9b534c8 100644
--- a/dom/media/MediaStreamVideoSink.h
+++ b/dom/media/MediaStreamVideoSink.h
@@ -33,6 +33,8 @@ public:
   virtual VideoFrameContainer* AsVideoFrameContainer() { return nullptr; }
   virtual void Invalidate() {}
 
+  virtual MediaStreamVideoSink* AsMediaStreamVideoSink() override { return this; }
+
 protected:
   virtual ~MediaStreamVideoSink() {};
 };