This hook is invoked whenever a PropertyNotify event is received\n\ on the root window. This indicates that an X window\n\ property has changed. Watching for window property changes can be used\n\ to construct your own custom window manager protocols, or interface\n\ to other desktop environments such as KDE or GNOME. The hook\n\ procedures are invoked with two arguments: the atom for the changed\n\ property and a boolean telling whether the property was deleted. \n\ These arguments are different from those passed to\n\ X-PropertyNotify-hook's procedures.