If "Always on top" is enabled, the &xcenter; will always remain
on top of all windows on the system. This is a "really-always-on-top" setting
and will affect the entire system.
Hint: If you don't like this setting, assign an object hotkey to the
&xcenter; on its
"Icon"
page. If you then press that object hotkey and the
&xcenter; is already open, it will be resurfaced to the top of all windows.