(Optional) Use the browser's "Install as App" (PWA) feature. This creates a shortcut that looks and feels exactly like a desktop app but runs entirely from the portable browser folder. 3. Using ElectronMail (The Community Favorite)
With some tweaking, you can force the official Windows app to run portably, but it’s : proton mail desktop app portable
Ensure you are using the official Proton binary packaged into a portable format (like those found via GitHub communities or PortableApps) to avoid "middle-man" malware. Conclusion Proton Mail does not offer an official portable
Proton is notoriously conservative regarding features that could compromise their security promise. However, the company has shown responsiveness to community needs (e.g., they added offline mode in 2024). However, the company has shown responsiveness to community
Look for the folder containing the core files (usually under lib/net45 or similar in Electron apps). Move to USB: Copy these files to your portable drive.