If I want to set my hotkeys in Minecraft and then come to the mouse buttons, the extra buttons and the mouse pad are all "key 3". How can I fix that?
Restarting and changing clients doesn't bring anything! It's not the version either!
Click Reset Keys in the lower left.
Did nothing
Go to the Minecraft folder and delete the options.txt file. If that doesn't change anything, let the https://de.malwarebytes.com/...dwcleaner/ run (if you have Windows).
Look in your mouse driver