在新的wordpress中，我们需要添加一些魔力：

remove_filter(\'nav_menu_description\', \'strip_tags\');
add_filter( \'wp_setup_nav_menu_item\', \'cus_wp_setup_nav_menu_item\' );
function cus_wp_setup_nav_menu_item($menu_item) {
                $menu_item->description = apply_filters(\'nav_menu_description\',  $menu_item->post_content );
                return $menu_item;
}