It does its job. Reliable. Not greedy, the free version is quite good.
However, there are some problems specific to Firefox.
There are regular connection problems.
-It always says there's a problem connecting your account, but your account connects (this isn't a huge problem, it's just confusing for some).
-Sometimes it connects and then disconnects after a split second. You have to wait a bit. (Meh, okay, but it's still a problem)
-Sometimes it doesn't connect automatically (this is a minor issue if you've pinned it to the top right, but it's very annoying)
-Loses the browser permissions?? You have to delete the add-on regularly and re-grant the requested permissions. (This is what's frustrating because the necessity of this can be forgotten.)

At least I experience these problems in both Windows and Cachy.

I can't tell what's currently going on but starting since today I can't use the addon anymore. Every time I try to connect to a server the whole browser freezes and if I wait long enough, it crashes. I have to open Firefox in troubleshooting mode and remove the addon, because as soon as I enable it it tries to connect to a server and the browser freezes.

I used to love ProtonVPN extension. It was quick and easy. However, now it is a nightmare. It started with the last version causing issues where you had to disable it and reopen the browser, but only on Linux. Well now, even if you disable it, it will lock your browser up and refresh the page every 30 seconds, on Windows and Linux. You have to completely disable and remove it, then go into the folder and delete the xpi in order to use your Firefox. I spent hours trying to place the blame on anything else. Even doing the Firefox troubleshooting where it disables the extensions did not stop this problem. Only completely removing the xpi and setting for it would stop this. I don't know what is going on over there, but I'm sure that you all should revert some of the changes you have been making, since version 1.3.x, would fix these issues. The nag pop-up for rating is horrible, and it doesn't matter if we had rated it or not. There should be a leave me alone box.
Edited, for typos and clarity.

Update: Reinstalled 1.2.16 and the issues with the lockup and reload and forgot to add that just opening the browser without loading a page would cause it to just use up all RAM in the system over about a 5 to 10 minute window. You could just sit there and watch it keep climbing.

The extension works fine, but suddenly it stops working; it says ‘network issue’ and I can't log out of my account or the VPN because the extension is somehow ‘frozen’ – I can't open the extension or its settings... Only by disabling the extension can I browse properly again.
I tried reinstalling the extension, but the same thing happened after a few minutes.



A temporary solution I’ve found is to disable the “connect automatically” option and to disable and re-enable the extension when it “freezes” and displays a connection error.

w

Easy to use, quick communication - excellent

Danke für dieses Addon. Läuft hier wunderbar.

please stop spamming with review request

Excellent , fonctionne parfaitement . Merci!

I love the service, but the extension is incredibly unreliable. Any time I try to set up a new connection, the entire browser locks up for tens of seconds. The connection drops off occasionally, to which the only fix is to disable then enable the extension, then wait for the browser to be responsive again.

There is a glut of VPN providers out there, including Firefox's own. I have had nothing but success with Proton's VPN service. Is it better than the others? I have no idea. The UI can be a little overbearing, especially on the mobile app, but its core functionality is solid.

fast and secure - recommend it

nice

Great features. Sometimes the UI can be unstable and it lacks features that you get from standalone vpn application but I do like that it only really needs to be on top of my web browsing rather than all my traffic. I'd like to see profiles added to the extension as maybe an easy feature that the extension is lacking.