Sweep Decal Backups

Sweeping Decal Backups will simply unlink decal backups, that where linked to your current scene collection, when projected or sliced decals were appended.
The backups beeing linked is an unfortunate, and undesired side effect of how Blender appends objects.

Selection

No selection is required, only the presence of linked decal backup objects.

Using Sweep Decal Backups