There are several other posts about this, but nothing recent.  When trying to setup the conroller to use an SMTP server, the "username" is being sent instead of the "sender address".  

The username/password fields are correctly being used for authentication to the SMTP server.  Mail is getting through to the server.  

However, mail fails to be delivered since the "sender address" is wrong.  The conroller appears to be parsing the "username" field instead.  Under strict DKIM/SPF configuration, mail using the wrong sender address will fail.

I have SMTP working correctly in many other instances.  

This bug exists in all cases when attempting to configure SMTP in either SSL mode (enabled/disabled) and via ports 465, 2525 and 587.