Ticket #33552: 33552.diff

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

@@ -110 +110 @@
                 require_once( ABSPATH . WPINC . '/class-wp-customize-panel.php' );
                 require_once( ABSPATH . WPINC . '/class-wp-customize-section.php' );
                 require_once( ABSPATH . WPINC . '/class-wp-customize-control.php' );
-                require_once( ABSPATH . WPINC . '/class-wp-customize-widgets.php' );
-                require_once( ABSPATH . WPINC . '/class-wp-customize-nav-menus.php' );
 
-                $this->widgets = new WP_Customize_Widgets( $this );
-                $this->nav_menus = new WP_Customize_Nav_Menus( $this );
+                /**
+                 * Fires at the beginning of WP_Customize_Manager's constructor.
+                 *
+                 * Allows plugins to add/override Customizer features.
+                 *
+                 * @see WP_Customize_Manager::__construct().
+                 * @since 4.4.0
+                 *
+                 * @param WP_Customize_Manager $this WP_Customize_Manager instance.
+                 */
+                do_action( 'customize_manager_construct', $this );
+
+                if ( ! isset( $this->widgets ) ) {
+                        require_once( ABSPATH . WPINC . '/class-wp-customize-widgets.php' );
+                        $this->widgets = new WP_Customize_Widgets( $this );
+                }
+
+                if ( ! isset( $this->nav_menus ) ) {
+                        require_once( ABSPATH . WPINC . '/class-wp-customize-nav-menus.php' );
+                        $this->nav_menus = new WP_Customize_Nav_Menus( $this );
+                }
 
                 add_filter( 'wp_die_handler', array( $this, 'wp_die_handler' ) );