Force TURN relay sets iceTransportPolicy: 'relay', discarding every direct candidate so only the TURN server on 5349 remains. If the call holds with it ticked, a guest behind a UDP-blocking firewall can join.
iceTransportPolicy: 'relay'
Recording is independent of the call. The browser captures its own camera and mic at 1080p / 6 Mbps with audio processing disabled, buffers every chunk to IndexedDB, and deletes each one only once the server acknowledges it. Kill your network mid-recording — chunks queue locally and upload when it returns.