Fatal error: Uncaught Error: Class "ApiBase" not found in /var/www/html/extensions/SemanticMediaWiki/src/MediaWiki/Api/BrowseBySubject.php:26 Stack trace: #0 {main} thrown in /var/www/html/extensions/SemanticMediaWiki/src/MediaWiki/Api/BrowseBySubject.php on line 26