Fatal error: Uncaught Error: Class "Sabre\Xml\Element\XmlFragment" not found in /var/www/illumine/vendor/sabre/dav/lib/DAV/Xml/Property/Complex.php:18 Stack trace: #0 {main} thrown in /var/www/illumine/vendor/sabre/dav/lib/DAV/Xml/Property/Complex.php on line 18