How to hide topbar?

function HideTopbarPlugin() {
  // this plugin overrides the Topbar component to return nothing
  return {
    components: {
      Topbar: function() { return null }
    }
  }
}

SwaggerUIBundle({
  url: "http://petstore.swagger.io/v2/swagger.json",
  dom_id: '#swagger-ui',
  presets: [
    SwaggerUIBundle.presets.apis,
    SwaggerUIStandalonePreset
  ],
  plugins: [
    SwaggerUIBundle.plugins.DownloadUrl,
    HideTopbarPlugin
  ],
  layout: "StandaloneLayout"
})