Types broken in React@19 & Next@15

[SaveliiLukash]

Issue

After migrating to React@19 & Next@15 as well as types-react@rc & types-react-dom@rc all type declarations for react-select seem to be broken.

Reproduction

1. Install the project with dependencies: https://github.com/SaveliiLukash/react-select-next-15/tree/main
2. Note zero IDE prompts for types of <Select /> in ./src/app/page-content.tsx
3. Run npm run build
4. Get the error on the screenshot below:

Extra info

My wild guess is that it might have something to do with React removing support for defaultProps and propTypes in v19. Or it might not...

[Methuselah96]

Thanks for the issue and the sample repo. The issue is actually with the JSX type being removed from the global scope in React 19. I created #5912 with a fix.

Note that you are likely upgrading to React 19 and Next.js 15 too soon. Both of these are still RC/canary releases, so I would recommend waiting until a stable version is released and libraries have time to make any necessary updates.

[SaveliiLukash]

@Methuselah96 Thanks a ton! The second version of our app is in development and is due to release in a few month, so we are lucky to have time and ability to experiment with latest Next & React.

[juandelacruz23]

Thanks for the issue and the sample repo. The issue is actually with the JSX type being removed from the global scope in React 19. I created #5912 with a fix.

Note that you are likely upgrading to React 19 and Next.js 15 too soon. Both of these are still RC/canary releases, so I would recommend waiting until a stable version is released and libraries have time to make any necessary updates.

Shouldn't a RC be suitable for libraries to start testing the upgrade?

[Methuselah96]

We should just be able to release it without it being an RC. The main blocker is that another maintainer needs to approve my PR before it can get merged.

I want to be cautious about merging it since it could technically be considered a breaking change for TypeScript users since it requires a higher version of @types/react than what was previously required. If a stable version of React 19 gets released and there are no other maintainers available to review the PR, then someone else can open a PR with the same changes, and I can review, merge, and release a new version, but I'd prefer to get another maintainer's approval due to the nature of the PR.

If you don't want to wait, as a workaround, you can add JSX to the global scope in your app:

import * as React from 'react';

declare global {
  namespace JSX {
    interface Element extends React.JSX.Element {}
    interface ElementClass extends React.JSX.ElementClass {}
    interface ElementAttributesProperty extends React.JSX.ElementAttributesProperty {}
    interface ElementChildrenAttribute extends React.JSX.ElementChildrenAttribute {}

    type LibraryManagedAttributes<C, P> = React.JSX.LibraryManagedAttributes<C, P>;

    interface IntrinsicAttributes extends React.JSX.IntrinsicAttributes {}
    interface IntrinsicClassAttributes<T> extends React.JSX.IntrinsicClassAttributes<T> {}
    interface IntrinsicElements extends React.JSX.IntrinsicElements {}
  }
}

or you can patch react-select locally with the changes from #5912.