Fatal error: Uncaught Error: Interface "Wikibase\Repo\Hooks\WikibaseEditFilterMergedContentHook" not found in /var/www/html/w/extensions/MathSearch/includes/Wikidata/ProtectUpstreamEntitiesHook.php:17 Stack trace: #0 {main} thrown in /var/www/html/w/extensions/MathSearch/includes/Wikidata/ProtectUpstreamEntitiesHook.php on line 17