> Since the first author name is zero characters long, the regex skips that line, and the fake second author line is used instead. Git ignores extra author lines after the first, so Codespaces looks at the second author line but Git looks at the first. This means we can create GitHub-signed commits with any author name+email.

Classic weird machine exploit of looking at two independent ad hoc parsers and finding inputs where they desynchronize and enter different states.