No close button on dialogs in gnome-shell.
Original title: "no way to close preference window in debian stable"
see attached image.
i have no idea why there is no close icon in the window title bar.
ideally, the buttons should be changed from 'save' to 'apply' and 'close'.
(from redmine: created on 2014-07-09, closed on 2014-09-29, relates #7242 (closed))