[BUG]: Video Stream does not show on the client in version 2.4.0-exp.4

Package version

2.4.0-exp.4

Environment

* OS: Windows 10
* Unity version: 2020.3.27f1

Steps To Reproduce

Code (snippets) below works on all the webRTC versions up to 2.4.0.-exp.3. In version 2.4.0-exp.4 the video stream seems to be going to the client (it shows in webRTC internals) but there is no video. I have looked at the changes between exp.3 and exp.4 and I cannot figure out what might be wrong (codec?). Maybe you could reproduce it using below code snippets and see what change/update is needed/

// Initialize WebRTC
public void Awake()
    {

        DontDestroyOnLoad(this.gameObject);
        Instance = this;
        WebRTC.Initialize(EncoderType.Hardware);
        EnhancedTouchSupport.Enable();

    }

   public void Update()
    {
        StartCoroutine(CaptureScreen());
    }

   // Create video stream track if not created. 
  // Get screen pixels
  // Call 'Update' delegate on the VideoStreamTrack
 //
    private IEnumerator CaptureScreen()
    {


        // Are we shutting down?
        if (Instance == null) yield return null;

        if (m_screen == null || (Screen.width != m_screen.width || Screen.height != m_screen.height))
        {
            CreateOrUpdateTrack();
        }
        

        yield return new WaitForEndOfFrame();
        m_screen.ReadPixels(new Rect(0, 0, Screen.width, Screen.height), 0, 0);
        m_screen.Apply();

        foreach (var update in m_listVideoStreamTrackUpdaters.Values)
        {
            try
            {
                update();
            }
            catch (Exception e)
            {
                Debug.LogErrorFormat("Failure during track update {0}", e);
            }
        }

    }

private void CreateOrUpdateTrack()
    {
        if (m_screen == null)
        {
            Screen.SetResolution(m_width, m_height, false, 60);
            m_screen = new Texture2D(Screen.width, Screen.height, TextureFormat.BGRA32, false);
        }
        else
        {
            m_screen.Resize(Screen.width, Screen.height);
        }

        var videoTrack = new VideoStreamTrack("screen", m_screen);
        // WebRTC.Update begins an infinite loop and does not allow us to perform our own capture before calling Update on the individual tracks.
        // Additionally, Track.Update is internal. This should be addressed.
        var trackUpdateMethod = videoTrack.GetType().GetMethod("Update", BindingFlags.NonPublic | BindingFlags.Instance);
        var update = (Action)trackUpdateMethod.CreateDelegate(typeof(Action), videoTrack);
        m_listVideoStreamTrackUpdaters.Add(videoTrack, update);
    }

////////// THE FOLLOWING PART IS TO SHOW WEBRTC NEGOTIATION, CONFIGURATION AND HOW AND WHEN THE VIDEO TRACK IS ADDED TO THE RTCPeerConnection.

    void BeginNegotiation(Signaling signaling, PlatformSessionDescription e)
    {
        RTCSessionDescription offer;
        offer.type = RTCSdpType.Offer;
        offer.sdp = e.sdp;
        var connectionId = e.playerId;
        if (m_mapConnectionIdAndPeer.TryGetValue(connectionId, out RTCPeerConnection target))
        {
            Debug.Log("Removing existing player: " + connectionId);
            target.Close();
            m_mapConnectionIdAndPeer.Remove(connectionId);
        }

        var pc = new RTCPeerConnection();
        if (!m_mapConnectionIdAndPeer.ContainsKey(e.playerId))
        {
            m_mapConnectionIdAndPeer.Add(e.playerId, pc);
        }

        pc.OnDataChannel = new DelegateOnDataChannel(channel => { OnDataChannel(pc, e.playerId, channel); });
        pc.OnIceCandidate = new DelegateOnIceCandidate(candidate =>
        {
            signaling.SendCandidate(e.playerId, candidate);
        });
        pc.OnIceConnectionChange = new DelegateOnIceConnectionChange(state =>
        {
            Debug.Log("PeerConnection ICE Connection State:" + state);
            if (state == RTCIceConnectionState.Disconnected)
            {
                pc.Close();
                m_mapConnectionIdAndPeer.Remove(e.playerId);
                if (e.playerId == 1)
                {
                    signaling.Close();
                }
            }
        });

        var conf = new RTCConfiguration
        {
            iceServers = m_clientConfiguration.peerConnectionOptions.iceServers,
            iceCandidatePoolSize = m_clientConfiguration.peerConnectionOptions.iceCandidatePoolSize == 0 ? 4 : m_clientConfiguration.peerConnectionOptions.iceCandidatePoolSize,
            iceTransportPolicy = m_clientConfiguration.peerConnectionOptions.iceTransportPolicy == "relay" ? RTCIceTransportPolicy.Relay : RTCIceTransportPolicy.All
        };

        Debug.Log("SetConfiguration: " + JsonUtility.ToJson(conf));

        var configError = pc.SetConfiguration(ref conf);
        Debug.Log("Config error: " + configError);
        if (configError != RTCErrorType.None)
        {
            throw new Exception("Unable to set WebRTC configuration");
        }

        // PLAT-1009
        // The WebRTC package supports receiving as well as sending video streams, but with different codecs (H264 for sending, VP8 for receiving).
        // The Hardware Encoder only supports H264 (which is what we want anyways). 
        // Forcing this into receive (from the browser pov)  forces the correct codecs.
        offer.sdp = offer.sdp.Replace("a=sendrecv", "a=recvonly");
        var setRemoteDescriptionOp = pc.SetRemoteDescription(ref offer);
        WaitForAsyncOperation(setRemoteDescriptionOp);

        foreach (var pair in m_listVideoStreamTrackUpdaters)
        {
            var sender = pc.AddTrack(pair.Key);
            m_rtpVideoSenders[pc] = sender;
        }

        if (m_audioStream != null)
        {
            foreach (var track in m_audioStream.GetTracks())
            {
                pc.AddTrack(track);
            }
        }

        RTCAnswerOptions options = default;
        var createAnswserOp = pc.CreateAnswer(ref options);
        WaitForAsyncOperation(createAnswserOp);


        var desc = createAnswserOp.Desc;
        signaling.SendAnswer(connectionId, desc);

        var setLocationDescriptionOp = pc.SetLocalDescription(ref desc);
        WaitForAsyncOperation(setLocationDescriptionOp);
    }

Current Behavior

Stream does not show on the browser client. WebRTC-internals show that the frames are going through fine but nothing on the client shows up.

Expected Behavior

No response

Anything else?

Please let me know what else I can provide to help.

Thank you,

Jacek