How can I fix error message given by React Developper Tools on the default React page?

Question

Summary

I would like to check elements on the react app, but my React Developper Tools on Google Chrome didn't work.

Proplem

Error message on the browser React Developper

This page is using the development build of React. 🚧

Note that the development build is not suitable for production.
Make sure to use the production build before deployment.

Open the developer tools, and "Components" and "Profiler" tabs will appear to the right.

What I tried to do

It was succeeded to build and execute a sample react app.

npm init react-app react_app
npm start

I can see the default React screen on http://localhost:3000/ and I didn't edit the created react app folder.

However, my React Developper didn't work with the red colored warning icon.

Answer 1

I had the same issue, then I tried in incognito window in chrome (ctrl + shift + N) which worked. Also, you can clear the cache or open a new tab and try there.