I’m a long-time Transmission user but I just learned that VPN killswitches are a thing (how did it take me so long!?). I would like to try another client which has this feature in case I forget to launch my VPN client before opening Transmission. Does anybody have any recommendations? Deluge? QBittorrent? Or any others?
Mullvad has one right in the GUI too, it’s called “Lockdown Mode” IIRC.
Also qBittorrent has a thing in preferences where you can bind it to a specific network interface, so you can just set it to whatever your VPN uses (for Mullvad Wireguard it’s ‘wg-mullvad’) and then if the VPN goes down it just won’t do anything.