Why is CDN Linking to ReactJS Not Working

Why does this not work? I checked the React docs and the CDN links seem to be all right.

<!DOCTYPE html>
<html lang="en">
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
      src="https://unpkg.com/[email protected]/umd/react.production.min.js"
      src="https://unpkg.com/[email protected]/umd/react-dom.production.min.js"
    const element = <h1>Hello, world</h1>;
    ReactDOM.render(element, document.querySelector("body"));


To use JSX, you need a transpiler such as Babel because JSX support is not built in to browsers.

You can use the Babel CDN:

<script src="https://unpkg.com/[email protected]/babel.min.js"></script>