An answer on How to disable HUD in Unity 2D? points to https://bugs.launchpad.net/unity-2d/+bug/947613 where the ALT key will be made reconfigurable.

Apart from emacs usage, I'm reasonably happy with using the ALT key to bring up the HUD. While using emacs though, the ALT key is tapped frequently to invoke commands. Should emacs be special cased with respect to the ALT key?

I'm wondering what the situation is with games; surely lots of games repurpose the ALT key for their own use, e.g. to fire a weapon?

If so, could the same be applied to Emacs, i.e. prevent the ALT key in emacs from triggering the HUD.

Edit: just realized how extensively I use the ALT key in the terminal: a quick tap of ALT+B to move back a word loses focus of the terminal and brings up the HUD. Aghch