Why is the content and the element itself not displayed in the Elements tab?

Question

JavaScript

While studying the react tutorial, I ran into a problem after connecting npx create-react-app my-app: the element with code blocks disappeared in the browser on the Elemets tab. Instead, I see this inscription (npm run build did not help): While studying the react tutorial, I encountered with a problem after connecting npx create-react-app my-app: the element with code blocks disappeared in the browser on the Elemets tab. Instead, I see this inscription (npm run build did not help):
You can add webfonts, meta tags, or analytics to this file.
The build step will place the bundled scripts into the tag.
To begin the development, run `npm start` or `yarn start`.
To create a production bundle, use `npm run build` or `yarn build`.
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