I have the same missing album art issue that squishy notes at the start of the thread. It is happening with MP3 and FLAC files with correctly embedded album art and a folder.jpg file in the directory.
Plex is also renaming albums and tracks. I have several examples of this, here is one:
I have 2 versions of Stick Figure’s album “Set In Stone”; an instrumental version and one with lyrics. Both are tagged correctly, have correct artist, album and file names that follow the Plex guidelines, both have folder.jpg files matching the album.
Plex shows both of them as the version with lyrics. To fix it I have to unmatched and fix match the album.
MusicBrainz has both albums named the same way as I do.
I am on Version 1.43.0.10231.
Scanner - Plex Music Scanner
Agent - Personal Media Artists
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