Fatal error: Uncaught Error: Interface 'Sabre\Xml\Element' not found in /home/malert/WebDAV/vendor/sabre/xml/tests/Sabre/Xml/Element/Mock.php:7 Stack trace: #0 {main} thrown in /home/malert/WebDAV/vendor/sabre/xml/tests/Sabre/Xml/Element/Mock.php on line 7