I have used Thunderbird as an email program for a number of years with a bellsouth.net domain. Effective April 1, AT&T is going to Open Authentication for email support. "AT&T is implementing a new email login technology, known as Open Authentication or OAuth, for AT&T email users. OAuth is a more secure way to log in that encrypts your credentials to protect them from hackers. On or shortly after April 1, 2018, AT&T email users will no longer be able to use an email application to send or receive AT&T email without using OAuth or a secure mail key." Thunderbird is identified as non-OAuth compliant, requiring the use of a secure mail key. Is any revision of Thunderbird under consideration to address this issue? What has been any experience with using a secure mail key?