WebRTC protocol is actively used in screen sharing. If you are under a restricted networking environment, please consult your networking department to have the below allowed/trusted for access.

WebRTC firewall setting requirements

TLS on port 443 or TCP(encrypted relay) over port 80 bidirectional.

the  UDP and TCP listening port requires a 3478 bidirectional

the  TLS and DTLS listening port requires a 5349 bidirectional

the  STUN servers, a 19302 is optional but strongly recommend

For UDP, a 49152 - 65535 (RTP/sRTP/RTCP) bidirectional is recommended for p2p transmission

Out-bound MQTT TCP port 8883