Firefox browser can't handle baseline H264 profile

Hello, maybe someone else seen the same issue.
When trying to establish a webrtc connection with the Firefox browser, my server sends a following message (video H264):

0:00:01.701967159    90 0x7fc2a0002030 LOG      webrtcsrc-signaller net/webrtc/src/signaller/imp.rs:172:gstrswebrtc::signaller::imp::Signaller::connect::{{closure}}::{{closure}}: Sending websocket message Peer(PeerMessage { session_id: "56a17f8d-2585-4d4b-9f2e-3009450a19e9", peer_message: Sdp(Offer { sdp: "v=0\r\no=- 9144757257615355393 0 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=ice-options:trickle\r\na=group:BUNDLE video0 audio1 application2\r\nm=video 9 UDP/TLS/RTP/SAVPF 96 98 99 100 101\r\nc=IN IP4 0.0.0.0\r\na=setup:actpass\r\na=ice-ufrag:uOJFtPAyRCKX4NDQcU3VExzLsFcfCWYc\r\na=ice-pwd:jRots1p0FnmxmwLoVqAq7lK84rAwBk/4\r\na=rtcp-mux\r\na=rtcp-rsize\r\na=sendonly\r\na=rtpmap:96 H264/90000\r\na=rtcp-fb:96 nack\r\na=rtcp-fb:96 nack pli\r\na=rtcp-fb:96 ccm fir\r\na=rtcp-fb:96 transport-cc\r\na=fmtp:96 packetization-mode=1;profile-level-id=42001f;level-asymmetry-allowed=1\r\na=rtpmap:98 red/90000\r\na=rtpmap:99 ulpfec/90000\r\na=rtpmap:100 rtx/90000\r\na=fmtp:100 apt=96\r\na=rtpmap:101 rtx/90000\r\na=fmtp:101 apt=98\r\na=ssrc-group:FID 2834502081 1415006916\r\na=ssrc:2834502081 msid:user1488703113@host-437c139 webrtctransceiver0\r\na=ssrc:2834502081 cname:user1488703113@host-437c139\r\na=ssrc:1415006916 msid:user1488703113@host-437c139 webrtctransceiver0\r\na=ssrc:1415006916 cname:user1488703113@host-437c139\r\na=mid:video0\r\na=fingerprint:sha-256 9E:33:DF:EB:63:72:42:77:49:8D:0C:0E:FC:61:51:C1:56:53:AF:05:D9:F7:61:8F:95:DD:7D:FF:99:1A:64:E8\r\na=rtcp-mux-only\r\nm=audio 0 UDP/TLS/RTP/SAVPF 97\r\nc=IN IP4 0.0.0.0\r\na=setup:actpass\r\na=ice-ufrag:uOJFtPAyRCKX4NDQcU3VExzLsFcfCWYc\r\na=ice-pwd:jRots1p0FnmxmwLoVqAq7lK84rAwBk/4\r\na=bundle-only\r\na=rtcp-mux\r\na=rtcp-rsize\r\na=sendonly\r\na=rtpmap:97 OPUS/48000/2\r\na=rtcp-fb:97 transport-cc\r\na=fmtp:97 sprop-stereo=1;sprop-maxcapturerate=48000\r\na=ssrc:1127273264 msid:user1488703113@host-437c139 webrtctransceiver1\r\na=ssrc:1127273264 cname:user1488703113@host-437c139\r\na=mid:audio1\r\na=fingerprint:sha-256 9E:33:DF:EB:63:72:42:77:49:8D:0C:0E:FC:61:51:C1:56:53:AF:05:D9:F7:61:8F:95:DD:7D:FF:99:1A:64:E8\r\na=rtcp-mux-only\r\nm=application 0 UDP/DTLS/SCTP webrtc-datachannel\r\nc=IN IP4 0.0.0.0\r\na=setup:actpass\r\na=ice-ufrag:uOJFtPAyRCKX4NDQcU3VExzLsFcfCWYc\r\na=ice-pwd:jRots1p0FnmxmwLoVqAq7lK84rAwBk/4\r\na=bundle-only\r\na=mid:application2\r\na=sctp-port:5000\r\na=fingerprint:sha-256 9E:33:DF:EB:63:72:42:77:49:8D:0C:0E:FC:61:51:C1:56:53:AF:05:D9:F7:61:8F:95:DD:7D:FF:99:1A:64:E8\r\n" }) })

and Firefox responds with VP8 inactive message:

0:00:02.007638187    90 0x7fc2a0002030 TRACE    webrtcsrc-signaller net/webrtc/src/signaller/imp.rs:324:gstrswebrtc::signaller::imp::Signaller::handle_message:<GstWebRTCSignaller@0x563ce91ed190> Received message {"type": "peer", "sessionId": "56a17f8d-2585-4d4b-9f2e-3009450a19e9", "sdp": {"type": "answer", "sdp": "v=0\r\no=mozilla...THIS_IS_SDPARTA-99.0 2114996636650547664 0 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=sendrecv\r\na=fingerprint:sha-256 16:EC:66:ED:36:A1:D4:E0:CB:95:24:4A:E2:40:CA:53:E5:AB:D5:FF:F5:9C:5C:81:EB:83:F8:E4:BD:89:9F:03\r\na=ice-options:trickle\r\na=msid-semantic:WMS *\r\nm=video 0 UDP/TLS/RTP/SAVPF 120\r\nc=IN IP4 0.0.0.0\r\na=inactive\r\na=mid:video0\r\na=rtpmap:120 VP8/90000\r\nm=audio 9 UDP/TLS/RTP/SAVPF 97\r\nc=IN IP4 0.0.0.0\r\na=recvonly\r\na=fmtp:97 maxplaybackrate=48000;stereo=1;useinbandfec=1\r\na=ice-pwd:d5a493a07b92e452116a851e083e1c78\r\na=ice-ufrag:721f69a3\r\na=mid:audio1\r\na=rtcp-mux\r\na=rtpmap:97 opus/48000/2\r\na=setup:active\r\na=ssrc:3561002322 cname:{bb14ec44-0966-49c0-bccb-5e6242dd83d7}\r\nm=application 9 UDP/DTLS/SCTP webrtc-datachannel\r\nc=IN IP4 0.0.0.0\r\na=sendrecv\r\na=ice-pwd:d5a493a07b92e452116a851e083e1c78\r\na=ice-ufrag:721f69a3\r\na=mid:application2\r\na=setup:active\r\na=sctp-port:5000\r\na=max-message-size:1073741823\r\n"}}

which leads to:

0:00:02.007849785    90 0x7fc2a0002030 WARN              webrtcsink net/webrtc/src/webrtcsink/imp.rs:3238:gstrswebrtc::webrtcsink::imp::BaseWebRTCSink::handle_sdp_answer: consumer from session 56a17f8d-2585-4d4b-9f2e-3009450a19e9 refused media 0: Some("m=video 0 UDP/TLS/RTP/SAVPF 120\r\nc=IN IP4 0.0.0.0\r\na=inactive\r\na=mid:video0\r\na=rtpmap:120 VP8/90000\r\n")

and a connection close.

Why Firefox could respond with VP8 to the H264 request?

Same issue is described here: Cannot establish WebRTC connection (different codecs and payload type in SDP) - Stack Overflow, changing H264 profile from baseline to main resolved the issue, created a bug for Firefox: 1900194 - establishing webrtc session: firefox can't handle H264 baseline profile properly

Somehow profile=main fixes the issue only when using cpu encoding, on gpu encoder it still fails. profile=constrained-baseline fixed issue for both cpu and gpu. Firefox is very picky about profile-level-id value…