title: admin menus Joomla 3.3.1 disappeared
body: <p>All admin menus in Joomla 3.3.1 suddenly disappeared!
  I worked at the site's user groups and adjusted a little CSS using firebug, when I suddenly lost all admin menubar, buttons / content in the subheader and content in the header
  None change in the core files and no errors are shown</p>
  
  <p>You can see the image....<img src="https://i.stack.imgur.com/250qj.jpg" alt="The backend without any menuitems"></p>