Thanks for reaching out. This isn't currently supported in SmarterMail, so I went ahead and changed your Question to a Proposed Idea. Other users who agree with this implementation can show their support and get it in front of the developers.
As someone not-so-technical and unfamiliar with what this is, can you give a quick rundown? Having a better idea of what it entails could also help other users to know if this is something they'd like to see as well.