That command would install mangohud.
What I did was installing Goverlay from AUR and make sure that mangold is not enabled systemwide.
Change the shortcut and make sure mangohud is hidden at start.
Then in f.ex steam you just add ‘mangohud %command%’ per game and use the shortut to show mangohud.
Becasue I suspect you actually want mangohud, you just don’t want it to show constantly.
If not, remove with command below in next post.