[React 19] : npm install react -- missing umd module

[Faim00]

UMD folder missing in React 19+ installation via npm

After installing React version 19.x.x using npm, the umd folder (which typically contains files like react.development.js and react.production.min.js) is missing from node_modules/react. These files are essential for UMD builds and are expected to be included in the package as per React's documentation. The same issue is observed for react-dom.

[adi-ydv-1]

If you need to use React in a UMD-compatible environment, you can consider using an older version of React that still includes the umd folder. Alternatively, you can explore other options, such as using a bundler like Webpack or Rollup to create a UMD-compatible bundle @Faim00

[magicdawn]

https://unpkg.com/react-umd/dist/react.umd.js
https://unpkg.com/react-umd/dist/react-dom.umd.js
https://unpkg.com/react-umd/dist/react-dom-client.umd.js

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I'm building this with rspack

But still a feature request for adding official UMD build back, since if react not providing UMD build, UI libraries will follow not providing UMD build. (e.g mui)

[guillaumebrunerie]

This is expected, see here: https://react.dev/blog/2024/04/25/react-19-upgrade-guide#umd-builds-removed.

[lofcz]

https://unpkg.com/react-umd/dist/react.umd.js https://unpkg.com/react-umd/dist/react-dom.umd.js https://unpkg.com/react-umd/dist/react-dom-client.umd.js

I'm building this with rspack

But still a feature request for adding official UMD build back, since if react not providing UMD build, UI libraries will follow not providing UMD build. (e.g mui)

The issue with this is ReactDomClient exporting ReactDOMClient into window, instead of its properties being available on ReactDOM, for example ReactDOM.createRoot(). I've written a monkey patch for restoring the behavior but it's a pretty ugly solution (although it works). Also, this produces binaries about 365Kb in size instead of the 200Kb I'd expect.

Edit: with some more tinkering I've reduced the built size to the expected 180Kb for both React and ReactDOM summed up. Updated script: https://gist.github.com/lofcz/85de631f88d9b6c49fdc2f4bde184193

This can be built by installing the dependencies and then rollup -c rollup.config.react.js
Built files: react19.production.min.js react-dom19.production.min.js