Catchable fatal error: Argument 2 passed to CategoryViewer::__construct() must implement interface IContextSource, null given, called in /srv/www/vhosts/komedia-due.de/subdomains/wiki/httpdocs/extensions/CategoryTree/CategoryPageSubclass.php on line 10 and defined in /srv/www/vhosts/komedia-due.de/subdomains/wiki/httpdocs/includes/CategoryViewer.php on line 61