React Developer Tools - Looks Different From Article

I am working through the React Developer Tools article, but when I open React Developer Tools in http://localhost:3000/ it looks different from what the article says I should be seeing. When I click on “Components” I see the following:

Then when I click on App and switch over to elements, I see $0 rather than $r and get an error when I try to use .setState() (see below):

Anyone have any idea why this could be happening?


I have the same problem

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I have also the same problem. Was there an update?

upping this as I’m going through the same trouble. Anyone got any hint as to how to solve this and what’s wrong?

It’s been 11 days and no solution, not even a moderator.

I am having the same problem.

Maybe due to the new version of React DevTools released in late 2019…?

I am also having this problem.

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Also having this problem. I even tried $r.setState({foo:“bar”}) and it returns the same error that OP describes.

My guess is that the new version of React DevTools has a different way of selecting and marking an element for access in the console.

Has anyone else found a way to do what the Ravenous setup instructions describe with $r ?

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Same problem here too 3 months later. I wonder if we all submit bug reports they may update it. If anyone has any ideas about how this was solved, let us know!

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There’s a decent little tutorial of the updates at
it has a fake browser and an explanation of the difference in the react devtools. Probably worth looking at, as the Codecademy one is now out of date. Good luck


thank you
for posting this link

I have a similar problem. Anyone knows why?

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I’m also having this problem. I’ve gathered that the Code Academy article doesn’t reflect an update to the React Developer Tools chrome extension that replaces the “React” tab with “Components” and “Profiler.” Supposedly “Components” shows what used to be under the “React” tab. However, I (like you) am not seeing a tree under “App” and am unable to modify components in the console. I may take a look at a different React app later and see if this is due to React Developer Tools being updated or something with the sample app, but it would be nice if Code Academy could bring this article up to speed to prevent further confusion.

On the page where you downloaded the extension, the Overview reads:

React Developer Tools is a Chrome DevTools extension for the open-source React JavaScript library. It allows you to inspect the React component hierarchies in the Chrome Developer Tools.

You will get two new tabs in your Chrome DevTools: “:atom_symbol: Components” and “:atom_symbol: Profiler”.

The Components tab shows you the root React components that were rendered on the page, as well as the subcomponents that they ended up rendering.

By selecting one of the components in the tree, you can inspect and edit its current props and state in the panel on the right. In the breadcrumbs you can inspect the selected component, the component that created it, the component that created that one, and so on.

If you inspect a React element on the page using the regular Elements tab, then switch over to the React tab, that element will be automatically selected in the React tree.

The Profiler tab allows you to record performance information.

This extension requires permissions to access the page’s React tree, but it does not transmit any data remotely. It is fully open source, and you can find its source code at