I just updated X on my site, but when trying to instal and validate cornerstone I get this error message
Fatal error: Call to undefined method WP_Error::has_errors() in /websites/123reg/LinuxPackage21/ki/at/ph/kiatphontipgym.com/public_html/wp-content/themes/x/framework/functions/updates/class-x-tgmpa-integration.php on line 276