I've got an interesting issue that's more of a frustration than an actual problem. Basically, I had to merge some catalogs and as a result I have ended up with a great number of duplicate entries in stacks.
It seems that most of the methods to remove duplicate images generally are designed for physical duplicates, or duplicated filenames, but in this case each of the images in a stack (there is always only two per stack) is actually the same image and thus linked to the same file in Explorer.
Is there a fast way to remove, or at least see only duplicate stacked images?