What is "Screen" in Control Mapping???

[Amandiam]

So recently I had to nuke the entire default control configuration(s) for a new controller I'm using, and while I had re-mapped the basic set-up for in-game interactions I seem to have lost the ability to quit to the homescreen on both my controller and keyboard.

I tried setting up a button or key for the "Home" hotkey, but that did nothing, either because it doesn't do what I think it does, or perhaps I had configured it wrong.

So that led me to experiment, I tried multiple options but nothing allows me to quit to the PPSSP homescreen like before with my escape key, I also tried "Screen" but that didn't do anything either, however my primary concern is whether or not I created an unwanted change by randomly trying out these keybinding's.

Like, what exactly is "Screen" and it's functionality? It doesn't take screenshots or whatever, so what is it?

Edit: Sorry it this is appearing as a copied thread, but it seems my first didn't show up.