When moving positions of cards in the sideboard in the deck editor, cards will sometimes duplicate. The cards themselves are not duplicating into my collection, and seem to be only a UI issue. The deck can still be saved, however when trying to queue into a game (ranked in my case), the deck will be illegal. This can be resolved by going back into the deck and out again, either saving changes or discarding them. This duplication seems to happen when moving cards into or out of the 7 card sideboard, and not within the same section.

Platform: PC