Topic is a bit of a mothfull, let me explain.

On Linux Mint cinamon - and presumably other distros, there is a function in window settings to help you if a window has move completely or partially offscreen called "special key to move and resize windows".

It defaults to ALT if you hold alt and press left mouse you can drag the window even if it's borderless or the window bars are outside of the visible area.

ALT + middle lets you access the window menu.

Both great features - until you encounter programs/games that wants you to use that key + the mouse for something else.

Most recently this is an issue in Baldurs gate 3 - alt key highlights loot, so you hold it often. Middle mouse lets you rotate the camera - but also brings up the window menu and if you are not fast enough to move away the mouse you will hit 'minimize window' and doing that crashes the game. Also it prevents you from clicking the loot label shown while holding ALT because the window manage assumes you are trying to move the window and so eats the mouse event.

TLDR;
I've change the key to super - but I am 100% going to forget this when next I actually need this feature, is there an (easy) way to automatically map the key to "disabled" while running a game ( or blender ) ?