Suspense

Suspense is a component in React that lets you specify the fallback content to display while waiting for a component to load. It is used in conjunction with lazy() to lazily load components.

import { lazy, Suspense } from 'react';
 
const LazyRoadmapRender = lazy(() => import('./RoadmapRender'));
 
export function App() {
  const [show, setShow] = useState(false);
  return (
    <>
      <button onClick={() => setShow(true)}>Show</button>
      {show && (
        <Suspense fallback={<div>Loading...</div>}>
          <LazyRoadmapRender />
        </Suspense>
      )}
    </>
  );
}

Until the RoadmapRender component is loaded, the Suspense component will display the Loading... fallback content.