Steam Networking (P2P) issues under CrossOver in macOS

[iblowmymind]

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

Playing multiplayer Steamworks P2P games for Windows through CodeWeavers' CrossOver almost never works when the VPN is enabled. Around half of the time, steam launches with no connection (though this can be mitigated by passing the -udpforce flag). This happens regardless if I add CrossOver.app to split tunneling or not.

Expected Behavior

Steam networking and multiplayer games to work fine.

Steps to Reproduce

1. Install Steam thru CrossOver
2. Launch a game that requires Steam P2P networking for multiplayer
3. You'll face timeout issues until you disconnect from the VPN and wait for the Steam Friends list to reconnect.

Failure Logs

Operating system version

macOS 26.4.1

Mullvad VPN app version

2026.2

Additional Information

No response