static function startup()
 {
     global $wgScriptPath;
     foreach (array('wgUseAjax') as $globalVar) {
         global ${$globalVar};
         if (!${$globalVar}) {
             die("This extension requires \${$globalVar} = true; in LocalSettings.php. Either disable the extension or change LocalSettings.php, accordingly.\n");
         }
     }
     // static properties initialization (various paths)
     self::$ExtDir = str_replace("\\", "/", dirname(__FILE__));
     // filesys path with windows path fix
     $dir_parts = explode('/', self::$ExtDir);
     $top_dir = array_pop($dir_parts);
     # currently two separate editings of the same page by the same user are considered a single edit
     self::$ScriptPath = $wgScriptPath . '/extensions' . ($top_dir == 'extensions' ? '' : '/' . $top_dir);
     // apache virtual path
     self::$alwaysEditClickEvent = false;
     self::$onLoadScript = '';
     self::$groupWeights = array('*' => 1, 'user' => 2, 'bureaucrat' => 3, 'sysop' => 4);
 }