Handling of missing ice-ufrag/ice-pwd and DTLS fingerprint

[fippo]

https://www.rfc-editor.org/rfc/rfc8829.html#section-5.8.3
declares that fingerprint, setup and ice-ufrag/ice-pwd must be present.

https://www.rfc-editor.org/rfc/rfc8829.html#section-5.3.1 says that

However, if any mandatory SDP attributes are missing or functionality listed as mandatory-to-use above is not present,
this MUST be treated as an error and MUST cause the affected "m=" sections to be marked as rejected

This is not how browsers behave, they throw an error when attempting to set the remote description along these lines:

const sdp = `v=0
o=- 0 3 IN IP4 127.0.0.1
s=-
t=0 0
m=video 9 UDP/TLS/RTP/SAVPF 100
c=IN IP4 0.0.0.0
a=rtcp-mux
a=sendonly
a=mid:video
a=rtpmap:100 VP8/90000
a=fmtp:100 max-fr=30;max-fs=3600
a=fingerprint:sha-256 A7:24:72:CA:6E:02:55:39:BA:66:DF:6E:CC:4C:D8:B0:1A:BF:1A:56:65:7D:F4:03:AD:7E:77:43:2A:29:EC:93
`;
const pc = new RTCPeerConnection()
pc.setRemoteDescription({type: 'offer', sdp}); // throws

Throwing an error seems fine to me, this is as fatal as it gets (and should be rare)