Often cover art images marked as "Front" are unsuitable for tagging music files because they are not square (e.g.: box sets, digipak covers, fatbox covers, etc.), and some purist editors insist that these images be listed ahead of proper square tagging images. In that way, the proper images are never selected within Picard. This could be resolved by adding a new cover art type "Tagging" and providing an option in Picard to give preference to images with that type when selecting an image for file tagging.

This has been discussed in https://community.metabrainz.org/t/uploading-squared-images-to-caa/265031