rem: if (ul.childNodes.length > 0) { $(this.popup).empty().append(ul).show(); } else { $(this.popup).css({visibility: 'hidden'}); this.hidePopup(); 
add: if (this.popup) { if (ul.childNodes.length > 0) { $(this.popup).empty().append(ul).show(); } else { $(this.popup).css({visibility: 'hidden'}); this.hidePopup(); } 
context: Drupal.jsAC.prototype.found = function (matches) {  // If no value in the textfield, do not show the popup.  if (!this.input.value.length) {    return false;  }  // Prepare matches  var ul = document.createElement('ul');  var ac = this;  for (key in matches) {    var li = document.createElement('li');    $(li)      .html('<div>'+ matches[key] +'</div>')      .mousedown(function () { ac.select(this); })      .mouseover(function () { ac.highlight(this); })      .mouseout(function () { ac.unhighlight(this); });    li.autocompleteValue = key;    $(ul).append(li);  }  // Show popup with matches, if any  if (ul.childNodes.length > 0) {    $(this.popup).empty().append(ul).show();  }  else {    $(this.popup).css({visibility: 'hidden'});    this.hidePopup();  }}
meta: 6801	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/6801/d5e9aad52bd44f8265c22b9e261faa7ae52f9064/autocomplete.js/clean/misc/autocomplete.js