Thanks for your efforts guys, I have deleted both FXO and metashaders2, to no avail, the gpu driver is constantly being updated as well as SteamVR, the problem only occurs when I start a mission, i.e. as soon as the "FLY" button appears, before that and after the flight there is nothing wrong, by the way my mask is still black, even if I play with its size or remove it completely, the black triangle persists ... don't know what to do anymore