1 star until issue on linux versions of firefox is fixed - also confirming the bug that other users reviewing have pointed out.
if browser/session restarts the extension needs to be disabled re-enabled or sometimes removed and reinstalled for it to work.
otherwise a great extension.

A simple to use VPN, especially for subscribers, but unreliable; the extension consistently disconnects intermittently, requiring disabling and re-enabling the extension several times to re-establish a connection.

For free it's a bull shit, worse than Browsec VPN.

Tres bon vpn facile a utiliser

It make the browser freeze then crash. (Midori browser)

The Proton VPN has worked flawlessly, however it should be pointed out that I have had a number of issues based around cloud based services either responding with a 403 or 500. These seem to relate to specific services which detect and deal with proxy related services with a service specific response. When disconnecting from the VPN the servers respond in an expected way.
I believe that this is VPN based and not Proton based. It seems some of those submitting reviews may have experienced this.

Great product but does need some work on its proxy handling ie when visiting a site with stock prices, the price changed and after I refreshed the price had not changed on the display. When I changed end point and refreshed then the site showed the correct new price.

why it faster thn native app, waever dat gud thing ig for desktop use windscribe

It's sometimes annoying, slow and unstable. But I can't say a bad word about it because it's free and only sometimes bad

This is an easy-to-set-up VPN to use, with a well-known privacy-oriented company, and it's fast, i.e. the speed drop is not at all noticeable even with the free (non-media) bandwidth.

Unfortunately, if the extension is kept running while the computer goes to sleep, etc., the internet connection for the browser becomes unstable, including not being able to connect to any website. Turning off the extension restores the normal connection, but turning the extension back on still causes problems. At this point, removing and reinstalling the extension is required to get it working again. This is non-ideal. Some other reputable VPN providers may be easier to work with than this.

Good extension, but I confirm the bug reported by another user. If I close Firefox (Ubuntu snap) with the VPN connected and shut down my computer, at restart when I launch Firefox there's a notifiation indicating that the VPN is connected but the browser cannot reach any website and the extensions seems broken (blank menu on icon click). The only way to retrieve a working Firefox situation is to unistall the extension (if only disabled, Firefox stops working when reenabled).