Ah that makes sense! From what I observed, after attempting to select a level, I couldn't do anything with the menu at all any more (I had to close the game entirely).
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Huh... That definitely would be an unintended side effect and would be a bug if you couldn't interact at all with the menu anymore. Attempting to replicate the bug yielded nothing as I was still able to interact with it, but now I'm paranoid. I added the functioning level select in a post jam update so hopefully something like that won't occur anymore, but unfortunately you never know what these kinds of things.