Chrome 136+ SDP validation "Failed to execute 'setLocalDescription'"

[cdwhitman]

Started getting this error on Chrome versions 136+: "Failed to execute 'setLocalDescription' on 'RTCPeerConnection': Failed to set local offer sdp: Failed to set local video description recv parameters for m-section with mid='0'." After doing some research I found that Chrome 136 tightened SDP validation and no longer likes the H.264 recv parameters in the offer at setLocalDescription(offer).

I was able to get around the error and fix it (hackly) by adding a SDP sanitizer and to the publish function right before setLocalDescription. the sanitizer forces the video m= section to sendonly, removes H.264 packetization-mode=0 payloads and their RTX, rebuilds the m=video PT list so it matches what remains, and forces VP8 only.

I would really appreciate a non-hacky fix for this as I am sure Edge will be following suit with their SDP validation in a coming release.