Ticket #55499: 55499.patch

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

@@ -3285 +3285 @@
          * @since 4.9.0
          * @param array $settings Current settings to filter.
          * @return array Heartbeat settings.
+    * @global string $pagenow
          */
         public function add_customize_screen_to_heartbeat_settings( $settings ) {
                 global $pagenow;