class App extends React.Component {

  
  render() {
    let data = "Try\nenter\nenter\nenter";
    return (
      <div>
        <p>Won't work:</p> 
        {data.replace(/\n/g, '<br/>')}
        <p>This works</p>
        {
          data.split('\n').map( line => {
            return (<span>{line}<br/></span>)
          })
        }
      </div>
    );
  }
};

ReactDOM.render(
  <App></App>,
  document.getElementById("root")
);