Split tunnel with socks5 proxy inconsistent behavior between macOS and Windows

[wavygecko]

Is it a bug?

• I know this is an issue with the app, and contacting Mullvad support is not relevant.

I have checked if others have reported this already

• I have checked the issue tracker to see if others have reported similar issues.

Current Behavior

On macOS, when I enable Split Tunneling and add Firefox to the apps list, I am able to still configure Firefox to use the Mullvad SOCKS5 proxy which effectively allows me to use the VPN on all sites except for those in the proxy exceptions list.

However, when I enable Split Tunneling and add Firefox to that list on Windows, then configure Firefox to use the SOCKS5 proxy, the browser is not able to connect to the proxy/VPN and thus can no longer connect to any website.

Expected Behavior

I love how it works on macOS, because I can create an exclusion list of websites I don't want to use the VPN with.
I'd like to be able to do the same on Windows.

Steps to Reproduce

1. On Windows, Enable Split Tunneling
2. Add Firefox to Split Tunneling exclusions list
3. In Firefox, set up SOCKS5 following Mullvad's guide at https://mullvad.net/en/help/socks5-proxy#get-started
4. Try to connect to a website in Firefox - cannot connect :(

Failure Logs

No response

Operating system version

macos 14.5 and Windows 10

Mullvad VPN app version

2024.4

Additional Information

No response