If you are on a highly untrusted machine, signing out ensures session tokens are invalidated. Use Official Sources:
If you truly need a desktop email client with Proton Mail, the official is your starting point. It is not portable, but it allows you to use Thunderbird Portable alongside it. proton mail desktop app portable
. The official apps for Windows, macOS, and Linux are designed as standard installed applications. If you are on a highly untrusted machine,
Future development will focus on:
Even with a portable app, it's a good habit to log out if you are using a high-risk public computer. proton mail desktop app portable
