--- a/dom/media/MediaFormatReader.cpp
+++ b/dom/media/MediaFormatReader.cpp
@@ -282,24 +282,30 @@ MediaFormatReader::OnDemuxerInitDone(nsr
 
   if (videoActive) {
     // We currently only handle the first video track.
     mVideo.mTrackDemuxer = mDemuxer->GetTrackDemuxer(TrackInfo::kVideoTrack, 0);
     if (!mVideo.mTrackDemuxer) {
       mMetadataPromise.Reject(ReadMetadataFailureReason::METADATA_ERROR, __func__);
       return;
     }
-    mInfo.mVideo = *mVideo.mTrackDemuxer->GetInfo()->GetAsVideoInfo();
-    UniquePtr<TrackInfo> info(mVideo.mTrackDemuxer->GetInfo());
-    for (const MetadataTag& tag : info->mTags) {
-      tags->Put(tag.mKey, tag.mValue);
+    UniquePtr<TrackInfo> videoInfo = mVideo.mTrackDemuxer->GetInfo();
+    videoActive = videoInfo && videoInfo->IsValid();
+    if (videoActive) {
+      mInfo.mVideo = *videoInfo->GetAsVideoInfo();
+      for (const MetadataTag& tag : videoInfo->mTags) {
+        tags->Put(tag.mKey, tag.mValue);
+      }
+      mVideo.mCallback = new DecoderCallback(this, TrackInfo::kVideoTrack);
+      mVideo.mTimeRanges = mVideo.mTrackDemuxer->GetBuffered();
+      mTrackDemuxersMayBlock |= mVideo.mTrackDemuxer->GetSamplesMayBlock();
+    } else {
+      mVideo.mTrackDemuxer->BreakCycles();
+      mVideo.mTrackDemuxer = nullptr;
     }
-    mVideo.mCallback = new DecoderCallback(this, TrackInfo::kVideoTrack);
-    mVideo.mTimeRanges = mVideo.mTrackDemuxer->GetBuffered();
-    mTrackDemuxersMayBlock |= mVideo.mTrackDemuxer->GetSamplesMayBlock();
   }
 
   bool audioActive = !!mDemuxer->GetNumberTracks(TrackInfo::kAudioTrack);
   if (audioActive) {
     mAudio.mTrackDemuxer = mDemuxer->GetTrackDemuxer(TrackInfo::kAudioTrack, 0);
     if (!mAudio.mTrackDemuxer) {
       mMetadataPromise.Reject(ReadMetadataFailureReason::METADATA_ERROR, __func__);
       return;