Comment by bradfitz

See https://github.com/tailscale/tailscale/issues/2880 for some background.

The root problem this all came from is that users can't really run two VPN clients at a time. It rarely works due to them fighting over the same resources in various OSes. So we need to either add Mullvad support to Tailscale's client or Tailscale support to Mullvad's client. The former is tons easier.