https://technokracy.net/2012/02/09/Mac_Mail_and_Certificates/
Quick steps to setting up a free email certificate on a Mac
mac mail appmimecertificates
https://www.macrumors.com/2024/03/14/proton-mail-desktop-app-available-mac/?utm_source=dlvr.it&utm_medium=mastodon
Swiss-based privacy startup Proton today announced the availability of its end-to-end encrypted desktop mail app for macOS and Windows, with a Linux version in...
available for macdesktop appprotonencryptedmail