Fatal error: Uncaught Error: Class 'Contao\CoreBundle\Picker\AbstractPickerProvider' not found in /home/eberhardschwarze/public_html/vendor/contao/calendar-bundle/src/Picker/EventPickerProvider.php:26 Stack trace: #0 {main} thrown in /home/eberhardschwarze/public_html/vendor/contao/calendar-bundle/src/Picker/EventPickerProvider.php on line 26