website/playground/index.js/App/render
class App:  render() {
    const { loaded, availableOptions, version } = this.state;

    if (!loaded) {
      return "Loading...";
    }

    return (
      <React.Fragment>
        <VersionLink version={version} />
        <Playground
          worker={this.worker}
          availableOptions={availableOptions}
          version={version}
        />
      </React.Fragment>
    );
  }