This is not really a “Feature Request”; it’s more like just an FYI. But there is no “FYI” category.
I know the S/MIME topic has be discussed here before, and in depth; But since I feel strongly that encryption should not stop with http, here is a link to a FREE S/MIME certificate provider: https://www.instantssl.com/ssl-certificate-products/free-email-certificate.html
…until the day we can all get our free Let’s Encrypt S/MIME certs…
I don’t work for, nor have I ever worked for, anyone who provides any form of certificates.
Nor have I ever been “paid” to promote any free product.
Nor do I have any affiliation with InstantSSL or Comodo.
My “work” here is strictly as a volunteer.