--- a/dom/media/MediaDecoderStateMachine.cpp
+++ b/dom/media/MediaDecoderStateMachine.cpp
@@ -3689,23 +3689,27 @@ uint32_t MediaDecoderStateMachine::GetAm
          ? std::max<uint32_t>(sVideoQueueHWAccelSize, MIN_VIDEO_QUEUE_SIZE)
          : std::max<uint32_t>(sVideoQueueDefaultSize, MIN_VIDEO_QUEUE_SIZE);
 }
 
 nsCString
 MediaDecoderStateMachine::GetDebugInfo()
 {
   MOZ_ASSERT(OnTaskQueue());
+  int64_t duration =
+    mDuration.Ref() ? mDuration.Ref().ref().ToMicroseconds() : -1;
   return nsPrintfCString(
-           "MediaDecoderStateMachine State: GetMediaTime=%" PRId64 " GetClock="
+           "MediaDecoderStateMachine State: duration=%" PRId64
+           " GetMediaTime=%" PRId64 " GetClock="
            "%" PRId64 " mMediaSink=%p state=%s mPlayState=%d "
            "mSentFirstFrameLoadedEvent=%d IsPlaying=%d mAudioStatus=%s "
            "mVideoStatus=%s mDecodedAudioEndTime=%" PRId64
            " mDecodedVideoEndTime=%" PRId64 " mAudioCompleted=%d "
            "mVideoCompleted=%d",
+           duration,
            GetMediaTime().ToMicroseconds(),
            mMediaSink->IsStarted() ? GetClock().ToMicroseconds() : -1,
            mMediaSink.get(),
            ToStateStr(),
            mPlayState.Ref(),
            mSentFirstFrameLoadedEvent,
            IsPlaying(),
            AudioRequestStatus(),