--- mutter-3.26.1.orig/src/x11/window-x11.c	2017-11-02 15:54:20.308689000 +0100
+++ mutter-3.26.1/src/x11/window-x11.c	2017-11-24 14:34:21.508961615 +0100
 
@@ -2457,7 +2459,11 @@
 
           make_fullscreen = (action == _NET_WM_STATE_ADD ||
                              (action == _NET_WM_STATE_TOGGLE && !window->fullscreen));
-          if (make_fullscreen && window->has_fullscreen_func)
+          if (make_fullscreen)
             meta_window_make_fullscreen (window);
           else
             meta_window_unmake_fullscreen (window);