On my side, PA will download new artwork after steam track name updated, and show correctly on interface, lock screen background etc. Except the media notification .
Update: if a artwork already in PA cache, media notification seems update correctly
when playing stream, enabled prefer track cover for streams option, media notification artwork not updated after track name updated.
crDroid 9 / Android 13
Poweramp 945 play
stream server deploy using icecast2