[Web] Returned blob url directs to home page

[bloemy7]

5.2.0

Environment

• OS: all
• Browser: all

Describe the bug

In some edge cases, on web, the blob returned by stop recorder basically just redirects to the home page of my flutter app, and thus when I try to retrieve the .opus file from there, it's actually just html code.

To Reproduce

Unfortunately I have no exact reproduction steps. This happens in about ~5% of my users in production, at rather large scale. I have been unable to find any pattern on what users/browser/devices this is happening on. The only common issue is what is described above.

Expected behavior

I would expect the returned blob to point to a valid .opus file

Additional context

Setup is very standard. Wondering if this can be linked to some weird garbage collection edge case? In media_recorder_delegate.dart, in _onStop(), we first call await _reset() before returning the URL through the completer. The reset method empties the chunks, which is what the blob is created from, but nothing is retaining the blob or the URL created from it. This is pure speculation - just wondering if that might play a role here in race conditions in low memory environments?

Thanks for any help!