  var textarea = document.getElementById('importExport');
        if (sessionStorage) {
          sessionStorage.setItem('textarea', textarea.value);
        }
        var valid = true;
        try {
          Blockly.Xml.textToDom(textarea.value);
        } catch (e) {
          valid = false;
        }
        document.getElementById('import').disabled = !valid;
      }

      function logEvents(state) {
        var checkbox = document.getElementById('logCheck');
        checkbox.checked = state;
        