Some unusual keycodes can have controls bound to them in-game, but do not have their names accurately translated in the controls menu. In the image, I have bound Cut, Paste, Undo, F13, and F25. I attempted to also bind F100 and even F246, the highest F-keycode in existence, but upon restarting the game, they are not saved. Additionally, as seen in the second image, when using one of these keys, an error is printed to the log, despite them working as expected in-game, as far as I can tell.
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A potentially-outdated list of scancodes can be found here
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Thank you for your report!
We're actually already tracking this issue in MC-170376, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote or any additional information to the main ticket it would be appreciated.
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