avc1 is the name for H.264 (also called AVC) which is admittedly pretty confusing
avc1 is the name for H.264 (also called AVC) which is admittedly pretty confusing
MP4box has a great local web tool to test the mime type including the codecs parameter:
https://gpac.github.io/mp4box.js/test/filereader.html
Jake Archibald wrote a good article about this topic: https://jakearchibald.com/2022/html-codecs-parameter-for-av1/
Makes me wonder what the VRCTL8SC is doing