Posting to spread awareness because this one is obnoxious.
You basically can't make changes/view any decks affected (seems to be random which decks?) without remaking it entirely from scratch or importing. Several reports on the forums on this already so hopefully it gets resolved soon.
External link →Thanks for the report; we're looking into it. Based on our investigations, it appears to be caused by having the same card in the Bo1 and Bo3 sideboards for the deck, and having those cards in particular positions in those sideboards. So it will likely seem fairly random in which decks it's affecting. Recreating the deck exactly would hit the bug again, but rebuilding it with the Bo1 sideboard in a different order should work. We apologize for the inconvenience here.
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