/**
  * Execute a callback function at the end of initialisation
  */
 public function loadSpecialVars()
 {
     parent::loadSpecialVars();
     if (Maintenance::$indent === null) {
         // First script gets no indentation
         Maintenance::$indent = '';
     } else {
         // Others get one tab beyond the last
         Maintenance::$indent = Maintenance::$indent . "\t";
     }
 }