--- a/dom/media/mediasource/TrackBuffersManager.cpp
+++ b/dom/media/mediasource/TrackBuffersManager.cpp
@@ -1069,17 +1069,16 @@ TrackBuffersManager::OnDemuxerInitDone(n
         new DispatchKeyNeededEvent(mParentDecoder, crypto->mInitDatas[i].mInitData,
                                    crypto->mInitDatas[i].mType));
     }
 #endif // MOZ_EME
     info.mCrypto = *crypto;
     // We clear our crypto init data array, so the MediaFormatReader will
     // not emit an encrypted event for the same init data again.
     info.mCrypto.mInitDatas.Clear();
-    mEncrypted = true;
   }
 
   {
     MonitorAutoLock mon(mMonitor);
     mInfo = info;
   }
 
   // We now have a valid init data ; we can store it for later use.

--- a/dom/media/mediasource/TrackBuffersManager.h
+++ b/dom/media/mediasource/TrackBuffersManager.h
@@ -234,17 +234,16 @@ private:
   // Length already processed in current media segment.
   uint32_t mProcessedInput;
   Maybe<media::TimeUnit> mLastParsedEndTime;
 
   void OnDemuxerInitDone(nsresult);
   void OnDemuxerInitFailed(const MediaResult& aFailure);
   void OnDemuxerResetDone(nsresult);
   MozPromiseRequestHolder<MediaDataDemuxer::InitPromise> mDemuxerInitRequest;
-  bool mEncrypted;
 
   void OnDemuxFailed(TrackType aTrack, const MediaResult& aError);
   void DoDemuxVideo();
   void OnVideoDemuxCompleted(RefPtr<MediaTrackDemuxer::SamplesHolder> aSamples);
   void OnVideoDemuxFailed(const MediaResult& aError)
   {
     mVideoTracks.mDemuxRequest.Complete();
     OnDemuxFailed(TrackType::kVideoTrack, aError);