New Qubes user here. I struggled for a bit and want to clarify what I had trouble with for any other less experienced users.
I was thinking the DNS script wasn’t working because Mullvad’s leak checker kept telling me I was leaking. This was not because of the script DVM wrote, which works, but was actually from a Firefox browser setting.
When you do the leak check on mullvad’s site and read the DNS leak guide, it has the answer. You have to disble “DNS over HTTPS” setting in Firefox ESR. By default it is enabled and made it so I was using a Cloudflare DNS server nearby the VPN server.
Also it wasn’t clear to me by reading this thread, but the script DVM wrote needs to be run in the sys-mullvad-vpn-app qube terminal, not the Dom0 terminal. The script needs to be run again if you change the settings in the DNS blocking inside the Mullvad app, however it seems like you don’t need to run the script again just to change the VPN server if it has the same DNS blocking settings. The script also needs to be run again after reboot.
Could someone give specific instructions on how to set up the killswitch in the qvm-firewall? I barely know what I’m doing and don’t want to break anything since I have the VPN working now.
Thank you all.