VSCode debugger not stopping at breakpoints in react native app (After upgrading to expo 40.0.0)

I am developing a react native app with expo in VS Code on Windows 10.

Until last week, I was able to do the following:

1. Start the packager with "npm start" or "expo start"
2. Start the debugger ("Attach to packager") -> This opens Expo Developer Tools in the Browser
3. In the browser in Expo Developer Tools I click "run on android device" Expo Developer Tools

This would then start the app on the emulator. The Bottom tab of VSCode would turn orange, the loading indicator below the green debug play button would go away and debugging in VSCode (including stopping at breakpoints!) worked.

After upgrading expo from 37.0.0 to 40.0.0, this no longer works: After step 3, a browser window with "http://localhost:19000/debugger-ui/" opens. My suspicion is, that this window is keeping the VS Code debugger from working.

Here is my launch.json:

    {
      "configurations": [
        {
          "name": "Attach to packager",
          "cwd": "${workspaceFolder}",
          "type": "reactnative",
          "request": "attach"
        }
      ]
    }

What I tried:

• I tried fiddling with different run configs to no success.
• I have remote debugging enabled in the emulator.
• I tried the "Tunnel" / "LAN" / "Local" options in Expo Dev Tools to no avail.
• I did a fresh install on a second PC an I am facing the same issue.