Villager with a profession's trading screen becomes bugged when another villager takes on the roll of the bugged villager's profession despite there being only one workstation available for that profession.
(e.g One Librarian villager's trading screen becomes bugged after another villager became a librarian despite there being only one Lectern in the village).

Trading screen immediately closes once opened, bug only seems to go away when the original Profession Villager is near its workstation after said workstation is broken and placed back.