I have noticed this for a while, but just was too distracted on other things to report, sorry:
The filter bar has this handy feature where you can filter groups of files depending on their category type, say pictures, music, videos, or documents...
I've only tested this extensively on the music group but as far as I've noticed, it only filters out mp3, wav and wma files. It doesn't include m4a, ogg, mpa, flac, opus, ape etc. I often find myself just clicking on individual music file types instead of relying on the default music group filter. Dunno about the other categories like pictures but they probably could use some updating too -- or at least I suspect, given the shear number of image file types out there.