MUI v5 types have no suggestion for code completion in WebStorm

I'm trying to get suggestions for code completion in WebStorm on MUI components and get nothing. What's wrong?

TypeScript v4.4.4
WebStorm 2021.2.3
MUI v5.0.4

function App() {
  const { path, url } = useRouteMatch();
  return (
    <div className="App">
      <header className="App-header"></header>
      <Switch>
        <Route exact path={path}>
          <Button variant="contained">a123</Button>
          <Card>123</Card>
        </Route>
      </Switch>
    </div>
  );
}