text: var documentationIframe
  var DocumentationViewer = function(entry) {
      var editor = document.createElement('div')
      editor.className = 'documentation-viewer'
      if (!documentationIframe) {
          documentationIframe = document.createElement('iframe')
          documentationIframe.src = 'http://nodejs.org/docs/' + nodeVersion + '/api/index.html'
      }
      editor.appendChild(documentationIframe)
      return editor
  }