ace);
        output.value = Blockly.Xml.domToPrettyText(xml);
        output.focus();
        output.select();
        taChange();
      }

      function fromXml() {
        var input = document.getElementById('importExport');
        var xml = Blockly.Xml.textToDom(input.value);
        Blockly.Xml.domToWorkspace(workspace, xml);
        taChange();
      }

      // Disable the "Import from XML" button if the XML is invalid.
      // Preserve text between page reloads.
      function taChange() {
      