React: npm start - windows cannot find localhost

This is a WSL specific issue with one of the dependencies of react-scripts, more specifically open version 7.0.0.

To resolve, you can:

• switch to react-scripts 3.2.0 in your package.json, or
• run npm start from something else than WSL (e.g. Powershell), or
• wait for open and react to fix the issue

Bug report in React Scripts:
https://github.com/facebook/create-react-app/issues/8081

And the corresponding bug report in open:
https://github.com/sindresorhus/open/issues/154