Save the settings. Thunderbird will now sync your encrypted emails directly to your USB drive. Method 2: The Web App (PWA) Portable Browser Method
Plug your USB drive into any compatible computer and immediately access your configured mailbox. Methods to Achieve a Portable Proton Mail Setup
To help me tailor this setup specifically to your needs, please let me know: proton mail desktop app portable
While portability offers convenience, running an end-to-end encrypted email client from a removable drive introduces specific security risks that you must mitigate. 1. Host Machine Leakage (De-anonymization)
Before you pursue any of these methods, consider the threat model. Save the settings
Advanced users can use open-source utilities like Nativefier to create an executable wrapper around the Proton Mail web app. Install Node.js on a development machine.
If your workflow absolutely requires a portable Proton Mail setup, implement these security layers to mitigate the inherent risks: Methods to Achieve a Portable Proton Mail Setup
To understand the demand, one must first define "portability." In software terms, a portable application is one that can be run on a computer without installation. Unlike standard software that writes to the Windows Registry and scatters files across system folders, a portable app is self-contained, typically running from a USB flash drive. For a security product like Proton Mail, portability offers two distinct advantages: operational security (leaving no traces on the host machine) and accessibility (carrying your secure communications in your pocket).