If in windowed mode, while selecting a level's difficulty (in this case Claire's level) you can still click around in the level select screen accessing the unreleased and not implemented level cards. When you go to play a difficulty of whichever level you selected, it instead tries to load the unreleased level where you'll be stuck until you quit out.

(I also have a video if it would be helpful)

Version: 2026-08-14.beatbanger_0-037-public-19882808