Subject that ends with UTF-8, 85 or A0 e.g.:

[Dennis Preiser]

On Tue, Aug 02, 2022 at 08:55:53PM -0700, Kevin J. McCarthy wrote:
> -      while (ISSPACE (*buf))
> +      while (is_email_wsp (*buf))

I was also able to reproduce the issue (on macOS) and can also confirm
that with this patch, the issue no longer occurs.

Dennis