'Portal' cannot be used as a JSX component.

[rileymjohnson]

I have recently started getting an issue that say: 'Portal' cannot be used as a JSX component. I believe this may have something to do with the versions of @types/react and similar, but i have not figured it out.

[stephanmantler]

I've seen similar errors in other packages after switching to React 19, so it is likely to be related...

[maitrongnhan99]

I’m facing the same issue—has anyone found a solution?

[McSoud]

The issue happens when I returned createPortal(...args) directly from the component in my package. I simply wrapped it in a Fragment to remove the error.
The createPortal() is being compiled to import("react").ReactPortal as for the Fragment it's a import("react/jsx-runtime").JSX.Element.
I don't know if it's a React 19 problem as per @stephanmantler. But I never had that problem before.