Ordinarily I'd agree, but a starting hyphen isn't valid in a domain name anyway, so it's harmless. RFC 1035: "The labels [a grammar production rule for domain names] must follow the rules for ARPANET host names. They must start with a letter, end with a letter or digit, and have as interior characters only letters, digits, and hyphen. There are also some restrictions on the length. Labels must be 63 characters or less."
(And by the way, neither is a leading dot, which I use to my advantage to define hostname aliases in ~/.ssh/config which I can be sure will never clash with anything.)
(And by the way, neither is a leading dot, which I use to my advantage to define hostname aliases in ~/.ssh/config which I can be sure will never clash with anything.)