The bug

If an in-game control is bound to the APPS key (numeric ID 221 in options.txt) in 1.12.2 or a prior version, and then a newer version is loaded, that control will be set to "Not Bound".

It is still possible to bind controls to this key in modern versions, in which it displays as "Menu" (alphanumeric ID key.keyboard.menu), leading me to believe that the control becoming unbound is not intended.

How to reproduce

1. Have a keyboard with the "apps"/"menu" key - most modern Windows keyboards should have one
2. Load up version 1.12.2 or earlier
3. Bind a control to this key
4. Quit out of the game
5. Load up the latest supported version in that same profile
6. Check your key binds menu

Expected results

The control that was bound to "APPS" would automatically be converted over to "Menu".

Actual results

That control now says "Not Bound".

How to fix

Have old options.txt files which bind a key to 221 convert this to key.keyboard.menu instead of key.keyboard.unknown.