// Argument of type 'HTMLElement | null' is not assignable to parameter of type 'Element | DocumentFragment'.
// Type 'null' is not assignable to type 'Element | DocumentFragment'.ts(2345)
// typescript error on createRoot (React 18)
// const root = ReactDOM.createRoot(document.getElementById("root"))
--- add non-null assertion
const root = ReactDOM.createRoot(document.getElementById("root")!)