If reportbug is configured to use TLS but the configured
SMTP host declines TLS usage, then reportbug should
offer to continue sending the report without using
TLS.

TIA,
Colin S. Miller

That sounds like a terrible idea.. unless you meant to make reportbug
try STARTTLS in that case and then fail if this doesn't work.

But if the user asked for an encrypted communication, the app should not
fall back to sending it in clear text. That's the basis of all the
nastiness of downgrade attacks that could happen with STARTTLS and other
protocols that permit this kind of fallback.

The best option here should be to have a clear error message of what
didn't work.