Fatal error: Uncaught Error: Class "BookStack\Activity\Notifications\Handlers\BaseNotificationHandler" not found in C:\WebServer\htdocs\bookshelf\app\Activity\Notifications\Handlers\PageUpdateNotificationHandler.php:15 Stack trace: #0 {main} thrown in C:\WebServer\htdocs\bookshelf\app\Activity\Notifications\Handlers\PageUpdateNotificationHandler.php on line 15