Chromium cannot play Opus audio anymore -> YouTube breaks

In chromium-120.0.6099.109-r0.9296e4c0.apk, YouTube videos no longer play in Chromium and fail with the following error screen:

• URL: https://www.youtube.com/watch?v=HwRPZNrYsWo
• Error screen:
  screenshot

  
• Playback log from chrome://media-internals: playback.log.json (interesting message probably is "Cannot select FFmpegAudioDecoder for audio decoding")

This appears to have to do with the Opus audio codec, so I tried to make sample files with this codec here:

• http://rm.cloudns.org/~xonotic/temp/b-aac.mp4: plays fine
• http://rm.cloudns.org/~xonotic/temp/b-opus.mp4: lacks audio

This confirms this issue has to do with Opus. I do not understand though why YouTube does not fall back to AAC when encountering the error - but that's on YouTube's side, not ours. Apparently Chromium claims Opus is supported, tells that to YouTube, then fails when actually receiving Opus.

These issues do not occur in Firefox, and they do not occur in chromium-119.0.6045.159-r0.8155a7af.apk, which seems to be the last known good build I have.