I was able to connect a day ago. but this morning even it said connection was established, a "something went wrong" popup showed up for shortly and i couldn't open any website. I deleted and reinstalled the extension and now I can't log in to my account. It constantly says "something went wrong". It is my first time trying NordVPN. I highly consider cancelling my account and having my payback... Edit: Now it works flawlessly. But still gonna reduce one star cause of the experience.

It works after I reinstall this add-on. Even if it works now, I concern the problem like this happen time to time. I hope your add-on will be stabilized soon.
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There is similar problem like I experienced before happens today. I can log in but after I see the pop up 'you logged in successfully' the add-on still not logged in. I try to log in several times but the add-on keep shows 'log into your account'.
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After I saw your reply and I reinstall this add-on, It works! thx for your fast support.
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after I changed wifi router, it doesn't work. I can't log in this add-on. It says 'something went wrong'. Well, I can log in when I use other vpn however after it says 'You can now close this window', this add-on doesn't work.

Good, our free VPN service.

It's good for those who are already subscribed to the plan. All you have to do is login and you're able to connect right after it. It even supports closing Firefox and re-opening again that means once you turn the vpn on you can restart Firefox as much you like and the vpn will still be active. However, my only complain is it doesn't have much server in or near Australia.

Works well, except for one thing, on linux mint .local addresses are unreachable.