Browser Support • Audio-only AAC files not playing, works if part of MP4 files

Yes, I understand that, but when I tested it with Firefox (mobile, I don't have Firefox desktop at hand) the sounds played correctly when interacting with the site UI. I was prompted to save the file when visiting the file URL directly.
It is definitely some kind of guessing game in the browser's media handling, but it seems to have reached a point of agreement as people are using AAC without a container freely.

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