Time synchronisation between live stream and bullet chatting

[xfq]

From https://lists.w3.org/Archives/Public/public-web-and-tv/2020Jan/0007.html :

In a typical bullet chatting implementation for live streams, are comments distributed to clients in real time, e.g., over a WebSocket connection, and displayed immediately when received, without being synchronized to the media timeline?

As each client may be at a different playback position on the media timeline, is any timing information used to ensure the comments are relevant to each viewer? For example, what happens if I'm watching the live stream but 5 minutes behind the most recent playback position?