I have found a couple of comics that I duplicated but when I click on the little trash can it doesn't go away. I tried to clear all the fields but get the error that I cannot leave required fields blank.
there's a thread for listing duplicates, we admins can then go in and merge them (its an admin only feature for now, so is deleting)
The trash can icon you refer to is only to move an item from a list (like your collection, wantlist or follows). Perhaps the icon/functionality could be made clearer.