Encrypt your desktop email app with Proton Mail Bridge | Proton
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Our Bridge app allows you to add our end-to-end encryption to popular email apps, including Outlook, Thunderbird, and Apple Mail.

Finally got around to installing Protonmail Bridge and setting it up to work with Geary on Ubuntu…

Took me a little while to figure out that the bridge uses a custom password… (the setup instructions didn’t mention that)