React Router with Storage Access Headers

Steps to Reproduce

1. Run npm install to install dependencies.
2. Run npm run correct to start the app at http://localhost:3000 and serve a static iframe.html file located at /public/iframe.html via http://127.0.0.1:4000.
3. Open the iframe at http://127.0.0.1:4000.
4. Grant storage access by clicking the button inside the iframe.
5. You should see the URL from both window.location.href and request.url (exposed from the loader) which should be identical.
6. Reload the page (the URLs should still match).