One (1) MediaStreamTrack from Firefox to multiple Chromium tabs: <audio> does not play

[guest271314]

Streaming audio from one (1) MediaStreamTrack from Firefox to one Chromium tab plays back the audio when set at HTMLMediaElement.srcObject.

The goal is to load at least 20 tabs or <iframes>, separate browsing contexts, on Chromium using the same one (1) MediaStreamTrack sourced from Firefox.

When tab (2) on Chromium 97 connects to the same MediaStreamTrack from Firefox the the remote MediaStreamTrack fires unmute event, HTMLMediaElement fires loadedmetadata, play, and playing events, the timeline does not progress beyong 0:00.

Why does the nth tab not play back the MediaStream?

[guest271314]

I have not found a way to stream using one WebRTC PeerConnection to multiple WebRTC PeerConnection's. 

I created 20 PeerConnection instances using the same MediaStreamTrack and MediaStream on both Firefox and streamed to 20 PeerConnection instances on Chromium. 

about:webrtc on Firefox prints

  sdpSemantics: Not Provided

although I provide the value to the constructor

  const webrtc = new RTCPeerConnection({

      sdpSemantics: 'unified-plan',

    });

and 

  Unrecognized attribute: 0xc057

multiple times. Nonetheless I was able to verify the content is streamed to the nth PeerConnection using MediaRecorder.