Recommend mandatory STARTTLS for Google

[c960657]

Summary

The Action Mailer guide recommends using opportunistic TLS (enable_starttls_auto: true) for connecting to smtp.google.com.

This setting is vulnerable to man-in-the-middle attacks. Google definitely supports STARTTLS, so this should be required using enable_starttls: true.

[rails-bot[bot]]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[rails-bot[bot]]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[gregmolnar]

@ghiculescu Is this one still good to be merged?

[ghiculescu]

I think so, but it needs to be reviewed by someone from the core or committer teams. They will get to it, it can jus take a little while. Thank you for keeping it open.