macOS hosted runner does not route traffic through exit node

Environment

• Runner: macos-15
• Action: tailscale/github-action@v4
• Auth: OIDC / Workload Identity Federation
• Exit node configured after connect:

  sudo tailscale set --exit-node=<node> --accept-routes
  
  

Observed behavior

Tailscale connects successfully, and tailscale set --exit-node=... also succeeds.

However, outbound traffic does not appear to use the exit node on GitHub-hosted macOS runners:

• tailscale netcheck reports public IPv4 in the 13.105.117.x range
• curl ifconfig.me returns 13.105.117.x
• Expected: the public IP of the configured exit node
• Actual: the the GitHub-hosted runner public IP

We also verified that an HTTPS request to an external service still appears to originate from the runner IP rather than the exit node.

Comparison with Ubuntu

Using the same workflow and the same exit node:

Notes

• The v4.0.0 macOS DNS fix does not appear to address this case.
• This does not look like a DNS resolution failure: requests resolve and complete, but egress IP does not switch to the
  exit node.

Question

Is exit node routing expected to work on GitHub-hosted macOS runners, or is this currently unsupported/limited by the macOS runner environment?

Start by reproducing the workflow with tailscale/github-action@v4 on macos-15, using the documented tailscale set --exit-node command, and compare its egress IP with ubuntu-latest. Determine whether macOS hosted runners support exit-node routing; done means either identifying a required change that makes the macOS path route correctly or documenting the confirmed platform limitation.