Ticket #32496: 32496.diff

src/wp-includes/class-wp-customize-widgets.php

@@ -1380 +1380 @@
 
                 $updated_widget = $this->call_widget_update( $widget_id ); // => {instance,form}
                 if ( is_wp_error( $updated_widget ) ) {
-                        wp_send_json_error( $updated_widget->get_error_message() );
+                        wp_send_json_error( $updated_widget->get_error_code() );
                 }
 
                 $form = $updated_widget['form'];