https to http - ugly hack

// Change menu item links from https to http as checkout is https and it
// puts menu links to https and they don't work.
add_filter('wp_nav_menu', 'bdd_change_menu_https_to_http', 10, 2);
function bdd_change_menu_https_to_http($nav_menu, $args) {
    return str_replace('https', 'http', $nav_menu);
}