[terhechte]

Use the VPN from a VM. You can also configure Mullvad to use socks so that it can only be accessed from Firefox (which has OS independent socks settings)

[metadaemon]

I was under the impression the socks feature no longer works, are you currently using it?

[pulpfictional]

I am, through the mullvad add-on.

[therein]

Take their wireguard config, change allowed IPs to include only the IP of their SOCKS gateway.

And then use the SOCKS proxy over Wireguard while nothing else on your system is routed through it.

That's the only way you'll get Mullvad "split tunnel" on OSX.

Edit: Should have replied to the sibling comment but I guess this will do.

[metadaemon]

TIL, thanks!

[S201]

It works the same as always for me on Linux with SSH port forwards.

[jaystraw]

you can start chrome-based browsers with a flag from the commandline with os independent proxy settings