Fatal error: Uncaught Error: Class "WP_REST_Controller" not found in /var/www/andovercg/staging/wp-includes/rest-api/endpoints/class-wp-rest-widgets-controller.php:17
Stack trace:
#0 {main}
thrown in /var/www/andovercg/staging/wp-includes/rest-api/endpoints/class-wp-rest-widgets-controller.php on line 17