When Minecraft launched it was in full screen, even though I had full screen off. I turned off Full Screen, closed out Minecraft, and then relaunched Minecraft. Full Screen was on again even though I had turned it off.
Edit: Just booted up the game again and it didn't boot into full screen. I don't know why it did it before, however, I think it may be something that happens randomly.
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We're tracking this issue in MCL-14797, so this ticket is being resolved and linked as a duplicate.
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