GdkX11.x11_grab_server
function x11_grab_server(): void {
    // Gjs wrapper for gdk_x11_grab_server()
}
  Call GdkX11.X11Display.prototype.grab on the default display. To ungrab the server again, use GdkX11.x11_ungrab_server.
GdkX11.x11_grab_server/GdkX11.x11_ungrab_server calls can be nested.