Hello there.

I am running all my games with "mangohud prime-run" prefix to have a HUD on the screen and switch to the dedicated video on my laptop. I usually add bash -c "mangohud prime-run ..." to the Exec= string of the .desktop file, but this somehow doesn't work with the gog's start.sh - the game won't start without throwing any error.

The question is, how do I do this, whether within start.sh script or whatever?

The shell script is only an installer and what you want is to have the Mango HUD show up in your games. You will have to modify whatever file is used to start the game. Not quite sure how this works with games played using Wine as I never did try that.

EDIT: Those below me know more than me and I learn new things.

You can edit the start.sh file with a text editor and add the mangohud prime-run option there. Then it will always use it.

* Open the start.sh file with a text editor
* Usually on line 20 you will find the name of the executable (for example ./"ChildrenOfMorta.x86_64")
* Add "mangohud prime-run " at the beginning of this line => mangohud prime-run ./"ChildrenOfMorta.x86_64"

I hope that works for you

Why bother with that rigamarole when goverlay exists?