Firstly, it's great to see MP3Tag still going! I have not tagged MP3 files for about 10 years, and must have had MP3Tag years before that... but it looked very different.
I have just copied all my Flac files to MP3 and many do not have cover art in the ID3 or in the album folder.
Is there a way to globally add cover.jpg to the folder and also to each file, but to have MP3TAG do it in a batch rather than one album at a time? If so, I would love to know how.