xfce4-menueditor saves blank menu.xml file. Choosing File -> Save results in a blank menu.xml file in ~.config/xfce4/desktop/ after editing a custom ~.config/xfce4/desktop/menu.xml. Choosing File -> Save results in a blank menu.xml file in /etc/xdg/xfce4/desktop/ after editing /etc/xdg/xfce4/desktop/menu.xml. This happens every time. Help -> About xfce4-menueditor says: xfce4-menueditor 4.3.90.1
Thankfully, this is fixed in xfce4 4.4.0
closing the report then