Mailspring - Mailspring is a mail client for Mac, Windows and Linux.
Mutt - Mutt is a small but very powerful text-based mail client for Unix operating systems.
Thunderbird - Thunderbird is a free email application that's easy to set up and customize - and it's loaded with great features!
Alpine - Alpine is a fast, easy to use email client that is suitable for both the inexperienced email user...
The Bat - The Bat! is a secure desktop email client for Windows, designed to protect your correspondence against third-parties and to save your time.
Nextcloud Mail - 💌 Mail app for Nextcloud