The idea for the addon is great but its implementation is flawed since it suffers some major problems, namely:

1) too often it loses connection and when it does it doesn't signal it. It just stops all connection and the only possibility for you is to restart firefox.

2) It stores login credentials in a cookie. This is really bad behavior since if you start firefox always in private mode you have to insert them every time from scratch. Quite annoying. Considering that starting in private mode is probably quite common for those concerned about privacy, who are also those interested in VPNs, then it doesn't look a good design for a VPN addon. It would be better to store login credential either in firefox password manager or inside a preference section in the NordVPN window from the about:addons page

3) About this I am no sure but it seems to me that when the addon is launched then it disables looking in /etc/hosts for name resolution. If this is the case, then to me this is bad behavior since I use a customized hosts file for adblocking (which is faster than CyberSec).

Please fix all the above if possible.