Enable Strict Mode in React for Highlighting Potential Problems

Strict mode checks are run in development mode only; they do not impact the production build.

import React from 'react';

function ExampleApplication() {
  return (
    <div>
      <Header />
      <React.StrictMode>        <div>
          <ComponentOne />
          <ComponentTwo />
        </div>
      </React.StrictMode>      <Footer />
    </div>
  );
}

References
https://reactjs.org/docs/strict-mode.html