JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="root"></div>

Babel + JSX

class App extends React.Component {
  constructor() {
    super();
    this.state = { hasVisitedBefore: true };
  }

  componentDidMount() {
    // Get item from localStorage and save it to a constant.
    const hasVisitedBefore = localStorage.getItem('hasVisitedBefore');

    // Check if the user has visited the site (component) before.
    if (!hasVisitedBefore) {
      // If not, set the component state (or dispatch an action if you need)
      // Also set the localStorage so it's globally accessible.
      this.setState({ hasVisitedBefore: false });
      localStorage.setItem('hasVisitedBefore', true);
    }
  }

  render() {
    return (
      <div>
        {this.state.hasVisitedBefore
          ? 'Welcome back!'
          : 'Welcome for the first time!'}

        <button onClick={() => location.reload()}>Reload page</button>
        <button onClick={this.handleReset}>Reset</button>
      </div>
    );
  }

  handleReset() {
    localStorage.clear();
    location.reload();
  }
}

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