For some reason quit game doesn’t seem to work, maybe it’s the new patch? Tried it multiple times, with different key strokes, just doesn’t close the game.
I tried doing this on Ubuntu with desktop version with latest version 5.6.265 and it worked as expected with a preview window. What platform you are using this on and is it’s the web or desktop version of GDevelop?
Keep in mind, I don’t believe the Quit action works very well with a browser window if you are using this on a html build game or using the web version of GDevelop due to the way browsers handle this stuff.
Edit, I have no idea what happened, I patched it to the newest version and it now works.