The problem with Firefox when reuse mediaSection (maybe help someone)

mediasoup libraries
1

I see this comment in RemoteSdp.ts:
Yes, we can recycle a closed m=audio section with a new m=video.
But this logic not works on Firefox (I using Firefox-esr)
I have join 2 user: chrome and firefox. Chrome have 2 transport (consume and produce), Firefox is same.
Then I sharescreen with audio at chrome, Firefox receive both audio stream and video stream success
Then I stop sharescreen with audio at chrome
Then I sharescreen with audio again, this time Firefox have problem, it cannot consume. The browser show error:
InvalidAccessError: Remote description changes the media type of m-line ….

These SDP which Firefox receive:

{

  "type": "offer",

"sdp": "v=0\r\no=mediasoup-client 10000 1 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=extmap-allow-mixed\r\na=ice-lite\r\na=fingerprint:sha-384 1E:76:66:15:4C:5D:E2:42:90:7B:6F:58:72:1B:6B:09:6F:60:32:DD:84:5A:24:E3:6B:73:D7:EB:B5:13:C7:1D:8B:A1:CA:18:A4:CA:21:DE:A2:5B:0B:23:1B:6E:FE:50\r\na=ice-options:ice2\r\na=msid-semantic: WMS *\r\na=group:BUNDLE 0\r\nm=video 7 UDP/TLS/RTP/SAVPF 101 102\r\nc=IN IP4 127.0.0.1\r\na=rtpmap:101 VP8/90000\r\na=rtpmap:102 rtx/90000\r\na=fmtp:102 apt=101\r\na=rtcp-fb:101 nack \r\na=rtcp-fb:101 nack pli\r\na=rtcp-fb:101 ccm fir\r\na=rtcp-fb:101 transport-cc \r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:actpass\r\na=mid:0\r\na=msid:6c3552e0-8d00-4034-ab28-d4b5ff36e5b5 b4b5c8a4-3b5e-4388-986f-3a2be46fb9b8_XX.XXX.XX.XX_video_screen_8cb0c2df-2d28-490b-af9c-691e8e2c3c80_1775052039358_1775052039692\r\na=sendonly\r\na=ice-ufrag:lrqbwx4wwzx0b5igm8b8pyh5tku5smzt\r\na=ice-pwd:7potafmq6hjyljwigahaf4337m0ny85j\r\na=candidate:udpcandidate 1 udp 1076558079 YY.YYY.YY.YY 16390 typ host\r\na=end-of-candidates\r\na=ice-options:renomination\r\na=ssrc:450340260 cname:cVH326DGbnubVGTA\r\na=ssrc:450340261 cname:cVH326DGbnubVGTA\r\na=ssrc-group:FID 450340260 450340261\r\na=rtcp-mux\r\na=rtcp-rsize\r\n"

}

{

"type": "answer",

"sdp": "v=0\r\no=mozilla...THIS_IS_SDPARTA-99.0 9044022521588815331 0 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=extmap-allow-mixed\r\na=fingerprint:sha-256 C9:1B:18:37:D5:A3:1C:00:93:89:ED:FB:0A:A3:7B:72:C2:AB:09:02:4C:18:6C:67:31:E7:2D:05:EE:6F:48:00\r\na=ice-options:trickle\r\na=msid-semantic: WMS *\r\na=group:BUNDLE 0\r\nm=video 9 UDP/TLS/RTP/SAVPF 101 102\r\nc=IN IP4 0.0.0.0\r\na=rtpmap:101 VP8/90000\r\na=rtpmap:102 rtx/90000\r\na=fmtp:101 max-fs=12288;max-fr=60\r\na=fmtp:102 apt=101\r\na=rtcp-fb:101 nack\r\na=rtcp-fb:101 nack pli\r\na=rtcp-fb:101 ccm fir\r\na=rtcp-fb:101 transport-cc\r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11/recvonly http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:active\r\na=mid:0\r\na=recvonly\r\na=ice-ufrag:92eda315\r\na=ice-pwd:d2c9142d5710ebccecbb81b20545ba3d\r\na=ssrc:578738712 cname:{d2e18ba4-69c4-4bda-a028-9ed5ad76293e}\r\na=rtcp-mux\r\na=rtcp-rsize\r\n"

}


{

"type": "offer",

"sdp": "v=0\r\no=mediasoup-client 10000 2 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=extmap-allow-mixed\r\na=ice-lite\r\na=fingerprint:sha-384 1E:76:66:15:4C:5D:E2:42:90:7B:6F:58:72:1B:6B:09:6F:60:32:DD:84:5A:24:E3:6B:73:D7:EB:B5:13:C7:1D:8B:A1:CA:18:A4:CA:21:DE:A2:5B:0B:23:1B:6E:FE:50\r\na=ice-options:ice2\r\na=msid-semantic: WMS *\r\na=group:BUNDLE 0 probator\r\nm=video 7 UDP/TLS/RTP/SAVPF 101 102\r\nc=IN IP4 127.0.0.1\r\na=rtpmap:101 VP8/90000\r\na=rtpmap:102 rtx/90000\r\na=fmtp:102 apt=101\r\na=rtcp-fb:101 nack \r\na=rtcp-fb:101 nack pli\r\na=rtcp-fb:101 ccm fir\r\na=rtcp-fb:101 transport-cc \r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:actpass\r\na=mid:0\r\na=msid:6c3552e0-8d00-4034-ab28-d4b5ff36e5b5 b4b5c8a4-3b5e-4388-986f-3a2be46fb9b8_XX.XXX.XX.XX_video_screen_8cb0c2df-2d28-490b-af9c-691e8e2c3c80_1775052039358_1775052039692\r\na=sendonly\r\na=ice-ufrag:lrqbwx4wwzx0b5igm8b8pyh5tku5smzt\r\na=ice-pwd:7potafmq6hjyljwigahaf4337m0ny85j\r\na=candidate:udpcandidate 1 udp 1076558079 YY.YYY.YY.YY 16390 typ host\r\na=end-of-candidates\r\na=ice-options:renomination\r\na=ssrc:450340260 cname:cVH326DGbnubVGTA\r\na=ssrc:450340261 cname:cVH326DGbnubVGTA\r\na=ssrc-group:FID 450340260 450340261\r\na=rtcp-mux\r\na=rtcp-rsize\r\nm=video 7 UDP/TLS/RTP/SAVPF 127\r\nc=IN IP4 127.0.0.1\r\na=rtpmap:127 VP8/90000\r\na=rtcp-fb:127 nack \r\na=rtcp-fb:127 nack pli\r\na=rtcp-fb:127 ccm fir\r\na=rtcp-fb:127 transport-cc \r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:actpass\r\na=mid:probator\r\na=msid:probator probator\r\na=sendonly\r\na=ice-ufrag:lrqbwx4wwzx0b5igm8b8pyh5tku5smzt\r\na=ice-pwd:7potafmq6hjyljwigahaf4337m0ny85j\r\na=candidate:udpcandidate 1 udp 1076558079 YY.YYY.YY.YY 16390 typ host\r\na=end-of-candidates\r\na=ice-options:renomination\r\na=ssrc:1234 cname:probator\r\na=rtcp-mux\r\na=rtcp-rsize\r\n"

}

{

"type": "answer",

"sdp": "v=0\r\no=mozilla...THIS_IS_SDPARTA-99.0 9044022521588815331 1 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=extmap-allow-mixed\r\na=fingerprint:sha-256 C9:1B:18:37:D5:A3:1C:00:93:89:ED:FB:0A:A3:7B:72:C2:AB:09:02:4C:18:6C:67:31:E7:2D:05:EE:6F:48:00\r\na=ice-options:trickle\r\na=msid-semantic: WMS *\r\na=group:BUNDLE 0 probator\r\nm=video 49875 UDP/TLS/RTP/SAVPF 101 102\r\nc=IN IP4 192.168.0.155\r\na=rtpmap:101 VP8/90000\r\na=rtpmap:102 rtx/90000\r\na=fmtp:101 max-fs=12288;max-fr=60\r\na=fmtp:102 apt=101\r\na=rtcp-fb:101 nack\r\na=rtcp-fb:101 nack pli\r\na=rtcp-fb:101 ccm fir\r\na=rtcp-fb:101 transport-cc\r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11/recvonly http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:active\r\na=mid:0\r\na=recvonly\r\na=ice-ufrag:92eda315\r\na=ice-pwd:d2c9142d5710ebccecbb81b20545ba3d\r\na=candidate:0 1 UDP 2122252543 2001:3::d83e:f811:eb0c:69b1 57806 typ host\r\na=candidate:2 1 UDP 2122187007 192.168.0.155 49875 typ host\r\na=candidate:4 1 TCP 2105524479 2001:3::d83e:f811:eb0c:69b1 9 typ host tcptype active\r\na=candidate:6 1 TCP 2105458943 192.168.0.155 9 typ host tcptype active\r\na=ssrc:578738712 cname:{d2e18ba4-69c4-4bda-a028-9ed5ad76293e}\r\na=rtcp-mux\r\na=rtcp-rsize\r\nm=video 9 UDP/TLS/RTP/SAVPF 127\r\nc=IN IP4 0.0.0.0\r\na=rtpmap:127 VP8/90000\r\na=fmtp:127 max-fs=12288;max-fr=60\r\na=rtcp-fb:127 nack\r\na=rtcp-fb:127 nack pli\r\na=rtcp-fb:127 ccm fir\r\na=rtcp-fb:127 transport-cc\r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11/recvonly http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:active\r\na=mid:probator\r\na=recvonly\r\na=ice-ufrag:92eda315\r\na=ice-pwd:d2c9142d5710ebccecbb81b20545ba3d\r\na=ssrc:1069434725 cname:{d2e18ba4-69c4-4bda-a028-9ed5ad76293e}\r\na=rtcp-mux\r\na=rtcp-rsize\r\n"

}


{

"type": "offer",

  "sdp": "v=0\r\no=mediasoup-client 10000 3 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=extmap-allow-mixed\r\na=ice-lite\r\na=fingerprint:sha-384 1E:76:66:15:4C:5D:E2:42:90:7B:6F:58:72:1B:6B:09:6F:60:32:DD:84:5A:24:E3:6B:73:D7:EB:B5:13:C7:1D:8B:A1:CA:18:A4:CA:21:DE:A2:5B:0B:23:1B:6E:FE:50\r\na=ice-options:ice2\r\na=msid-semantic: WMS *\r\na=group:BUNDLE 0 probator 1\r\nm=video 7 UDP/TLS/RTP/SAVPF 101 102\r\nc=IN IP4 127.0.0.1\r\na=rtpmap:101 VP8/90000\r\na=rtpmap:102 rtx/90000\r\na=fmtp:102 apt=101\r\na=rtcp-fb:101 nack \r\na=rtcp-fb:101 nack pli\r\na=rtcp-fb:101 ccm fir\r\na=rtcp-fb:101 transport-cc \r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:actpass\r\na=mid:0\r\na=msid:6c3552e0-8d00-4034-ab28-d4b5ff36e5b5 b4b5c8a4-3b5e-4388-986f-3a2be46fb9b8_XX.XXX.XX.XX_video_screen_8cb0c2df-2d28-490b-af9c-691e8e2c3c80_1775052039358_1775052039692\r\na=sendonly\r\na=ice-ufrag:lrqbwx4wwzx0b5igm8b8pyh5tku5smzt\r\na=ice-pwd:7potafmq6hjyljwigahaf4337m0ny85j\r\na=candidate:udpcandidate 1 udp 1076558079 YY.YYY.YY.YY 16390 typ host\r\na=end-of-candidates\r\na=ice-options:renomination\r\na=ssrc:450340260 cname:cVH326DGbnubVGTA\r\na=ssrc:450340261 cname:cVH326DGbnubVGTA\r\na=ssrc-group:FID 450340260 450340261\r\na=rtcp-mux\r\na=rtcp-rsize\r\nm=video 7 UDP/TLS/RTP/SAVPF 127\r\nc=IN IP4 127.0.0.1\r\na=rtpmap:127 VP8/90000\r\na=rtcp-fb:127 nack \r\na=rtcp-fb:127 nack pli\r\na=rtcp-fb:127 ccm fir\r\na=rtcp-fb:127 transport-cc \r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:actpass\r\na=mid:probator\r\na=msid:probator probator\r\na=sendonly\r\na=ice-ufrag:lrqbwx4wwzx0b5igm8b8pyh5tku5smzt\r\na=ice-pwd:7potafmq6hjyljwigahaf4337m0ny85j\r\na=candidate:udpcandidate 1 udp 1076558079 YY.YYY.YY.YY 16390 typ host\r\na=end-of-candidates\r\na=ice-options:renomination\r\na=ssrc:1234 cname:probator\r\na=rtcp-mux\r\na=rtcp-rsize\r\nm=audio 7 UDP/TLS/RTP/SAVPF 100\r\nc=IN IP4 127.0.0.1\r\na=rtpmap:100 opus/48000/2\r\na=fmtp:100 minptime=10;useinbandfec=1;sprop-stereo=1;usedtx=0;ptime=10\r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:6 urn:ietf:params:rtp-hdrext:ssrc-audio-level\r\na=extmap:11 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:actpass\r\na=mid:1\r\na=msid:6c3552e0-8d00-4034-ab28-d4b5ff36e5b5 b4b5c8a4-3b5e-4388-986f-3a2be46fb9b8_XX.XXX.XX.XX_audio_screen_ee980597-0d25-4b96-b5aa-9f3896cda01a_1775052039624_1775052039722\r\na=sendonly\r\na=ice-ufrag:lrqbwx4wwzx0b5igm8b8pyh5tku5smzt\r\na=ice-pwd:7potafmq6hjyljwigahaf4337m0ny85j\r\na=candidate:udpcandidate 1 udp 1076558079 YY.YYY.YY.YY 16390 typ host\r\na=end-of-candidates\r\na=ice-options:renomination\r\na=ssrc:741370432 cname:cVH326DGbnubVGTA\r\na=rtcp-mux\r\na=rtcp-rsize\r\n"

}

{

"type": "answer",

  "sdp": "v=0\r\no=mozilla...THIS_IS_SDPARTA-99.0 9044022521588815331 2 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=extmap-allow-mixed\r\na=fingerprint:sha-256 C9:1B:18:37:D5:A3:1C:00:93:89:ED:FB:0A:A3:7B:72:C2:AB:09:02:4C:18:6C:67:31:E7:2D:05:EE:6F:48:00\r\na=ice-options:trickle\r\na=msid-semantic: WMS *\r\na=group:BUNDLE 0 probator 1\r\nm=video 42715 UDP/TLS/RTP/SAVPF 101 102\r\nc=IN IP4 171.243.48.78\r\na=rtpmap:101 VP8/90000\r\na=rtpmap:102 rtx/90000\r\na=fmtp:101 max-fs=12288;max-fr=60\r\na=fmtp:102 apt=101\r\na=rtcp-fb:101 nack\r\na=rtcp-fb:101 nack pli\r\na=rtcp-fb:101 ccm fir\r\na=rtcp-fb:101 transport-cc\r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11/recvonly http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:active\r\na=mid:0\r\na=recvonly\r\na=ice-ufrag:92eda315\r\na=ice-pwd:d2c9142d5710ebccecbb81b20545ba3d\r\na=candidate:0 1 UDP 2122252543 2001:3::d83e:f811:eb0c:69b1 57806 typ host\r\na=candidate:2 1 UDP 2122187007 192.168.0.155 49875 typ host\r\na=candidate:4 1 TCP 2105524479 2001:3::d83e:f811:eb0c:69b1 9 typ host tcptype active\r\na=candidate:6 1 TCP 2105458943 192.168.0.155 9 typ host tcptype active\r\na=candidate:3 1 UDP 1685987327 171.243.48.78 57421 typ srflx raddr 192.168.0.155 rport 49875\r\na=candidate:3 1 UDP 1685986815 171.243.48.78 65172 typ srflx raddr 192.168.0.155 rport 49875\r\na=ssrc:578738712 cname:{d2e18ba4-69c4-4bda-a028-9ed5ad76293e}\r\na=rtcp-mux\r\na=rtcp-rsize\r\nm=video 9 UDP/TLS/RTP/SAVPF 127\r\nc=IN IP4 0.0.0.0\r\na=rtpmap:127 VP8/90000\r\na=fmtp:127 max-fs=12288;max-fr=60\r\na=rtcp-fb:127 nack\r\na=rtcp-fb:127 nack pli\r\na=rtcp-fb:127 ccm fir\r\na=rtcp-fb:127 transport-cc\r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11/recvonly http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:active\r\na=mid:probator\r\na=recvonly\r\na=ice-ufrag:92eda315\r\na=ice-pwd:d2c9142d5710ebccecbb81b20545ba3d\r\na=ssrc:1069434725 cname:{d2e18ba4-69c4-4bda-a028-9ed5ad76293e}\r\na=rtcp-mux\r\na=rtcp-rsize\r\nm=audio 9 UDP/TLS/RTP/SAVPF 100\r\nc=IN IP4 0.0.0.0\r\na=rtpmap:100 opus/48000/2\r\na=fmtp:100 maxplaybackrate=48000;stereo=1;useinbandfec=1\r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:6 urn:ietf:params:rtp-hdrext:ssrc-audio-level\r\na=extmap-allow-mixed\r\na=setup:active\r\na=mid:1\r\na=recvonly\r\na=ice-ufrag:92eda315\r\na=ice-pwd:d2c9142d5710ebccecbb81b20545ba3d\r\na=ssrc:3238002923 cname:{d2e18ba4-69c4-4bda-a028-9ed5ad76293e}\r\na=rtcp-mux\r\n"

}


{

"type": "offer",

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{

"type": "offer",

  "sdp": "v=0\r\no=mediasoup-client 10000 6 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=extmap-allow-mixed\r\na=ice-lite\r\na=fingerprint:sha-384 1E:76:66:15:4C:5D:E2:42:90:7B:6F:58:72:1B:6B:09:6F:60:32:DD:84:5A:24:E3:6B:73:D7:EB:B5:13:C7:1D:8B:A1:CA:18:A4:CA:21:DE:A2:5B:0B:23:1B:6E:FE:50\r\na=ice-options:ice2\r\na=msid-semantic: WMS *\r\na=group:BUNDLE 0 probator 2\r\nm=video 7 UDP/TLS/RTP/SAVPF 101 102\r\nc=IN IP4 127.0.0.1\r\na=rtpmap:101 VP8/90000\r\na=rtpmap:102 rtx/90000\r\na=fmtp:102 apt=101\r\na=rtcp-fb:101 nack \r\na=rtcp-fb:101 nack pli\r\na=rtcp-fb:101 ccm fir\r\na=rtcp-fb:101 transport-cc \r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:actpass\r\na=mid:0\r\na=msid:6c3552e0-8d00-4034-ab28-d4b5ff36e5b5 b4b5c8a4-3b5e-4388-986f-3a2be46fb9b8_XX.XXX.XX.XX_video_screen_8cb0c2df-2d28-490b-af9c-691e8e2c3c80_1775052039358_1775052039692\r\na=inactive\r\na=ice-ufrag:lrqbwx4wwzx0b5igm8b8pyh5tku5smzt\r\na=ice-pwd:7potafmq6hjyljwigahaf4337m0ny85j\r\na=candidate:udpcandidate 1 udp 1076558079 YY.YYY.YY.YY 16390 typ host\r\na=end-of-candidates\r\na=ice-options:renomination\r\na=ssrc:450340260 cname:cVH326DGbnubVGTA\r\na=ssrc:450340261 cname:cVH326DGbnubVGTA\r\na=ssrc-group:FID 450340260 450340261\r\na=rtcp-mux\r\na=rtcp-rsize\r\nm=video 7 UDP/TLS/RTP/SAVPF 127\r\nc=IN IP4 127.0.0.1\r\na=rtpmap:127 VP8/90000\r\na=rtcp-fb:127 nack \r\na=rtcp-fb:127 nack pli\r\na=rtcp-fb:127 ccm fir\r\na=rtcp-fb:127 transport-cc \r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:actpass\r\na=mid:probator\r\na=msid:probator probator\r\na=sendonly\r\na=ice-ufrag:lrqbwx4wwzx0b5igm8b8pyh5tku5smzt\r\na=ice-pwd:7potafmq6hjyljwigahaf4337m0ny85j\r\na=candidate:udpcandidate 1 udp 1076558079 YY.YYY.YY.YY 16390 typ host\r\na=end-of-candidates\r\na=ice-options:renomination\r\na=ssrc:1234 cname:probator\r\na=rtcp-mux\r\na=rtcp-rsize\r\nm=video 7 UDP/TLS/RTP/SAVPF 101 102\r\nc=IN IP4 127.0.0.1\r\na=rtpmap:101 VP8/90000\r\na=rtpmap:102 rtx/90000\r\na=fmtp:102 apt=101\r\na=rtcp-fb:101 nack \r\na=rtcp-fb:101 nack pli\r\na=rtcp-fb:101 ccm fir\r\na=rtcp-fb:101 transport-cc \r\na=extmap:1 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:4 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:9 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:11 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap-allow-mixed\r\na=setup:actpass\r\na=mid:2\r\na=msid:6c3552e0-8d00-4034-ab28-d4b5ff36e5b5 b4b5c8a4-3b5e-4388-986f-3a2be46fb9b8_XX.XXX.XX.XX_video_screen_28ab66c1-e876-46d1-b225-94821968a4c0_1775052053096_1775052053365\r\na=sendonly\r\na=ice-ufrag:lrqbwx4wwzx0b5igm8b8pyh5tku5smzt\r\na=ice-pwd:7potafmq6hjyljwigahaf4337m0ny85j\r\na=candidate:udpcandidate 1 udp 1076558079 YY.YYY.YY.YY 16390 typ host\r\na=end-of-candidates\r\na=ice-options:renomination\r\na=ssrc:868389655 cname:cVH326DGbnubVGTA\r\na=ssrc:868389656 cname:cVH326DGbnubVGTA\r\na=ssrc-group:FID 868389655 868389656\r\na=rtcp-mux\r\na=rtcp-rsize\r\n"

} 

then crash ………………

So i modified this line in RemoteSdp.ts:
const oldMediaSection = this._mediaSections.find(m => m.closed && m.getObject().type === kind);
And it works all both Firefox, Chrome, Safari.

Can you tell me if what I did is correct?