switch {
	case fh.NonUTF8:
		fh.Flags &^= 0x800
	case (utf8Require1 || utf8Require2) && (utf8Valid1 && utf8Valid2):
		fh.Flags |= 0x800
	}

	fh.CreatorVersion = fh.CreatorVersion&0xff00 | zipVersion20 // preserve compatibility byte
	fh.ReaderVersion = zipVersion20

	// If Modified is set, this takes precedence over MS-DOS timestamp fields.
	if !fh.Modified.IsZero() {