Double click switch to window mode ???

[LunaMoo]

@JumpingY start by making sure ppsspp isn't running, open "ppsspp.ini" which should be memstick\PSP\SYSTEM or directly in ppsspp folder whenever you keep it(.ini can be hidden on some systems, but it's a text file so you should easily recognize it) and anywhere under [General] add FullscreenOnDoubleclick = False, can be directly under like this:

Code:

[General]
FullscreenOnDoubleclick = False

This will as you can guess disable this feature. You don't need to care about doing the same for per-game config files as this is global setting, not used per-game.