content: import React from 'react';
  import { render } from 'react-dom';
  import App from './components/App';
  
  window.onerror = (message, filename, lineno) => {
      console.warn(`ERROR in ${filename} (${lineno}): ${message}`);
  }
  
  // Now we can render our application into it
  render(<App />, document.getElementById('app'));
  