`cargo fmt --all` wanted a `vec!` wrap and a trailing newline in repro_mail.rs, which `main` has been carrying unformatted. The gate is `cargo fmt --all -- --check`, so it was red before this and for nothing to do with the changes around it. `benilla-octo.zip` is a zipped snapshot of this checkout, taken by hand to move the tree somewhere. It is binary, redundant with the history it would land in, and 10 MB of it.