React 19 Source Migration Patterns

Reference for every source-file migration required for React 19.

Quick Reference Table

Pattern	Action	Reference
`ReactDOM.render(...)`	→ `createRoot().render()`	See references/api-migrations.md
`ReactDOM.hydrate(...)`	→ `hydrateRoot(...)`	See references/api-migrations.md
`unmountComponentAtNode`	→ `root.unmount()`	Inline fix
`ReactDOM.findDOMNode`	→ direct ref	Inline fix
`forwardRef(...)` wrapper	→ ref as direct prop	See references/api-migrations.md
`Component.defaultProps = {}`	→ ES6 default params	See references/api-migrations.md
`useRef()` no arg	→ `useRef(null)`	Inline fix add `null`
Legacy Context	→ `createContext`	→ api-migrations.md#legacy-context
String refs `this.refs.x`	→ `createRef()`	→ api-migrations.md#string-refs
`import React from 'react'` (unused)	Remove	Only if no `React.` usage in file