Fatal error: Uncaught Error: Class "MediaWiki\SpecialPage\SpecialPage" not found in /var/www/html/w/extensions/Wikibase/repo/includes/Specials/SpecialWikibasePage.php:20 Stack trace: #0 {main} thrown in /var/www/html/w/extensions/Wikibase/repo/includes/Specials/SpecialWikibasePage.php on line 20