[RFC] Add Support for React 19 Compatibility in Plasmo

[sashamorozov]

How do you envision this feature/change to look/work like?

Plasmo should work with React 19 without blocking updates due to version checks. Right now, the framework checks for a specific React version and fails if React 19 is used. Additionally, there is no folder or template similar to cli/plasmo/templates/static/react18, which would make it easier to support the new version.

The idea is to remove or loosen the version checks and add a React 19-specific folder/template if needed.

What is the purpose of this change/feature? Why?

The lack of support for React 19 prevents developers from upgrading to the latest React version. This blocks access to new features, better performance, and long-term updates, making projects feel stuck on older versions.

Adding support would let developers upgrade without worries and keep their projects modern.

(OPTIONAL) Example implementations

1. Remove or update the React version checks to support React 19
2. Add a react19 folder/template, similar to the existing react18 folder in cli/plasmo/templates/static/
3. ...

(OPTIONAL) Contribution

• I would like to contribute to this RFC via a PR

Verify canary release

• I verified that the issue exists in plasmo canary release

Code of Conduct

• I agree to follow this project's Code of Conduct
• I checked the current issues for duplicate problems.

[PawelGawlikDev]

@louisgv Any update about it?

[nahtnam]

Having this issue too. Specifically the error I get is "No supported UI library found". In case anyone else is searching the repo for this message

[KozlovAndrii]

For anyone encountering this issue, here's the root cause:

Plasmo does not currently support React v19.
To see the React versions that are compatible with Plasmo, refer to the following file: Plasmo Supported Templates.

The code responsible for this version check can be found here: Manifest Factory UI Library

if (!(await isAccessible(staticPath))) { 
  throw new Error(uiLibraryError); 
}

[pippinmole]

We really want this. It's causing issues with our pnpm monorepo where we have a nextjs app requiring react19, but adding our browser extension to the monorepo (and demanding react18, and its relevant @types/react), its causing type errors on our nextjs project(?)

[jaeil-wiki]

Agree. Need support React 19.

[pippinmole]

I've made a PR which should hopefully add support for React 19 #1167

[pippinmole]

I've made a PR which should hopefully add support for React 19 #1167

Merged. Could you try out v0.90.0 and report any issues here or in a separate issue. Thanks 🙏