Same here. I'm using nordvpn + networkmanager + openvpn as described in the
tutorial link given by davidgil.
It works flawlessly.
If you want to make sure if everything is tunneled and there are no leaks,
you can use this little bash script that has the name "firewall.sh" on my
computer. I don't know much about ufw but it seems to do the job:
---------------------------------
#!/bin/bash
sudo ufw reset
sudo ufw default deny incoming
sudo ufw default deny outgoing
sudo ufw allow out on tun0 from any to any
sudo ufw enable
---------------------------------
If you want to undo the firewall rules, I use a script called
"unfirewall.sh":
---------------------------------
#!/bin/bash
sudo ufw reset
sudo ufw default allow incoming
sudo ufw default allow outgoing
sudo ufw enable
