275829 2024-06-24 16:38:18 -0700 setCodecPreferences should accept or video codecs regardless of mimeType case 2026-03-11 06:28:12 -0700 1 1 1 Unclassified WebKit WebRTC WebKit Nightly Build Unspecified Unspecified RESOLVED DUPLICATE 307157 InRadar P2 Normal --- 1 ahmad.saleem792 webkit-unassigned webkit-bug-importer youennf oldest_to_newest 2042839 0 ahmad.saleem792 2024-06-24 16:38:18 -0700 Hi Team, While investigating WPT failures, I noticed that Safari / WebKit (including Chrome due to relying on libwebrtc) fails following: Test Case: https://wpt.fyi/results/webrtc/RTCRtpTransceiver-setCodecPreferences.html?label=master&label=experimental&aligned&q=Safari%3Afail This assert following error: "InvalidModificationError: RTCRtpCodecCapability bad mimeType" Which stems from: https://searchfox.org/wubkat/rev/38fb2ecadd89df8d6d7114cc2b030188d744aeb0/Source/WebCore/Modules/mediastream/libwebrtc/LibWebRTCRtpTransceiverBackend.cpp#92 webrtc::RtpCodecCapability rtcCodec; if (codec.mimeType.startsWith("video/"_s)) rtcCodec.kind = cricket::MEDIA_TYPE_VIDEO; else if (codec.mimeType.startsWith("audio/"_s)) rtcCodec.kind = cricket::MEDIA_TYPE_AUDIO; else return Exception { ExceptionCode::InvalidModificationError, "RTCRtpCodecCapability bad mimeType"_s }; So this might need tweaking. Web-Spec: https://w3c.github.io/webrtc-pc/#dom-rtcrtptransceiver-setcodecpreferences While spec says in Step 7: For each codec in codecs, If codec does not match any codec in codecCapabilities, throw InvalidModificationError. _____ So if I am not mistaken Chrome and Safari are doing right thing while Firefox / Gecko is wrong here. Just wanted to get input before suggesting that we should update WPT or not. Thanks! 2044090 1 webkit-bug-importer 2024-07-01 16:39:11 -0700 <rdar://problem/130928226> 2045519 2 ahmad.saleem792 2024-07-10 04:19:56 -0700 Gecko is right here - https://github.com/w3c/webrtc-pc/pull/2975 Thanks Youenn for input. :-) 2189094 3 ahmad.saleem792 2026-03-11 06:27:29 -0700 I fixed it will find relevant commit and link, never realized, I filed this. 2189095 4 ahmad.saleem792 2026-03-11 06:28:12 -0700 *** This bug has been marked as a duplicate of bug 307157 ***