Fatal error: Uncaught Error: Class "SMW\MediaWiki\Specials\Admin\TaskHandler" not found in /var/www/html/extensions/SemanticMediaWiki/src/MediaWiki/Specials/Admin/AlertsTaskHandler.php:16 Stack trace: #0 {main} thrown in /var/www/html/extensions/SemanticMediaWiki/src/MediaWiki/Specials/Admin/AlertsTaskHandler.php on line 16