Highlight duplicated items in inventories /xivdupes.
Highlight stackable items in the inventory that are not stacked.
2 images from the plugin's author. Click one to see it full size.
Not right now. XIVDupeFinder was last built for Dalamud API 8, and current Dalamud is API 15, so the installer doesn't list it at all. It will come back if the author updates it. In the meantime, the similar plugins below do work.