I noticed that ALT-Click has a reserved function in Mint. It seems to interact with the active window. I looked this up and it seems that it can't be disabled.
The next best thing for me would be to disable the ALT key altogether. The problem is that once the ALT-Click combination is pressed, the reserved function remains active until the ALT key is pressed again (or presumably until the reserved function is fulfilled – whatever that is).
This is causing me problems. Am I correct that ALT-Click cannot be disabled and, if so, can the ALT key itself be disabled – ie leaving the mouse unaffected by whether ALT is pressed or not?