Cutting multiple embedded album covers at once

[ohrenkino]

See here for the basic check whether each file really has a cover:

How to get any song's cover to be shown when you play it on a car for example?

Each time I play songs in my mom's car I don't see the song's covers, except one album from Justin Bieber that the car shows its cover. Is there possibly something that should be mentionned in the songs tags so the car can detect their covers? Thanks in advance!

See here for possible problems with the picture itself:

Cover Art from Discogs doesn't show in Pioneer car stereo

Before you rate the behaviour that you found as bug, it would be nice that you do all the basic checks of the files like file integrity, check the player requirements, check how other players show the same file, check which tag versions were in the files prior to using the web sources and afterwards check whether this happens to all pictures that you embed or just one release - such things. I doubt that MP3tag embeds picture in different ways.

and finally: for best separation of the files, the following tag fields should be filled:
ALBUMARTIST, ARTIST, ALBUM, TITLE, perhaps even TRACK