Show only this box is useful to set some boxes to full-screen if they don't have their own full-screen feature, usually games. The problem is that the box is reloaded and the first time that I didn't know it I waited about 1 minute to let a game load completely and then I clicked Show only this box and the box was reloaded. For me it's better to set that the page closes all other nodes except the selected box, reloading it is annoying.
