protected function get_fields($item, $depth, $args = array(), $id = 0)
    {
        ob_start();

        /**
         * Get menu item custom fields from plugins/themes
         *
         * @since 0.1.0
         * @since 1.0.0 Pass correct parameters.
         *
         * @param int $item_id Menu item ID.
         * @param object $item Menu item data object.
         * @param int $depth Depth of menu item. Used for padding.
         * @param array $args Menu item args.
         * @param int $id Nav menu ID.
         *
         * @return string Custom fields HTML.
         */
        do_action('wp_nav_menu_item_custom_fields', $item->ID, $item, $depth, $args, $id);

        return ob_get_clean();
    }