I just learned about another email service, but this one
optionally supports OpenGPG.
[o] 65GB storage
[o] attachments up to 50MB
Externally produced pub keys are supported so that you can
exchange encrypted messages with other users such as protonmail
and startmail as long as the systems use OpenGPG.
--- OpenXP 5.0.50
* Origin: (2:221/1.58)