I noticed that flac 1.4.0 was released this weekend.
Out of curiosity I checked it out, and noticed they also have released a 'testbench', which consists of 64 tracks that each has its own challenges that could make a player/decoder trip. (freeze, crash etc.)https://xiph.org/flac/2022/09/08/decoder-testbench.html
I checked them all, and almost all of them played without any problem.
The only exceptions were:
#55 (which combines a lot of 'you shouldn't do this' in one track)
MusicBee won't load it and hangs at 'scanning'.
#59 (which has artwork embedded as AV1)
It plays, but no artwork is displayed.
So with all but one problematic files MusicBee passed with flying colours.
Perhaps something could be improved so that #55 would also play (but I don't think anyone will ever encounter a track having all these issues at the same time), and perhaps it would be good to look at embedded AV1 images being recognised and displayed.
But I think both are pretty much academical and hypothetical issues.