Fatal error: Uncaught Error: Class "SilverStripe\Core\Extension" not found in /home/sjnew/public_html/vendor/silverstripe/asset-admin/code/Extensions/RemoteFileModalExtension.php:24 Stack trace: #0 {main} thrown in /home/sjnew/public_html/vendor/silverstripe/asset-admin/code/Extensions/RemoteFileModalExtension.php on line 24