Digital signatures and email signatures are two different things.
An email signature is simply a closing part of an email containing customizable message.
Digital signature is a cryptographic feature designed to ensure that the person who sent you an email is not an impostor.
It contains a certificate and a public key which originates from your digital ID.
While digital signatures can still be forged, they make it more difficult to send "fake" emails.
We currently support digital signatures when both, the sender and the recipient are using CyberFear email service.