public function slugSafeString($handle, $maxlength = 128)
    {
        $handle = preg_replace('/[^\\p{L}\\p{Nd}\-_]+/u', ' ', $handle); // remove unneeded chars
        $handle = preg_replace('/[-\s]+/', '-', $handle); // convert spaces to hyphens
        return trim(Utf8::substr($handle, 0, $maxlength), '-'); // trim to first $max_length chars
    }