On drag and drop from 5e compendium using OGL (though it may be with other sheets aswell) sometimes the search resets results in the compendium panel and results in a floating asset of the spell/item name on the screen, this is always on top of sheets etc and although it can be resolved by a refresh of the game it can be an annoyance if you are creating a group of NPC's etc. If you need screenshots let me know and I will upload once I recreate the issue.