Wee need to upgrade to babel 8 to upgrade plugin-transform-class-properties. The project currently uses @vitejs/plugin-react 5.1.4, which bundles Babel 7. The latest 6.0.3 supports Vite 8 but removes that integrated Babel transformation. Our vite.config.ts currently relies on react({ babel: { plugins: […] } }) for legacy decorators and class properties.
Moving to plugin-react 6 requires:
- Upgrade @vitejs/plugin-react to 6.x.
- Add and configure @rolldown/plugin-babel.
- Move the decorator/class-property configuration out of react().
- Align all Babel plugins on one major version.
- Ensure TypeScript transforms run before class-feature transforms.
- Verify legacy MobX decorators retain identical semantics.