I don't know if this is part of this bug but if you Shift left click an item that is already in a full chest it just deletes it, which ties into the game not registering that your inventory is full.
It is there I used a wooden sword and, if not all, most of the wither skeletons dropped their heads.
Andrew hunter
I don't know if this is part of this bug but if you Shift left click an item that is already in a full chest it just deletes it, which ties into the game not registering that your inventory is full.