WordPress menu: How to make www.link.com/#name never contain current_page_item class?

a bit hacky, but it works:

add_filter('nav_menu_css_class', 'remove_some_menu_classes', 420 ,3);
function remove_some_menu_classes($classes, $item, $args){
  if(strpos($item->url, '#order') !== false)
    // in the 2nd array put the classes you want removed
    return array_diff($classes, array('current_page_item', 'current-menu-item'));

  return $classes;
}