docs: function (index) {
              var count = this.insertedOptionsCount();
  
              if (index < 1 || index > count) {
                  this.$logError(this.INDEX_OUT_OF_BOUNDS, [count, index]);
                  return;
              }
  
              this.removeHighlight();
  
              var suggestionNode = this._getSuggestionsContainer().children[index - 1];
  
              this._addClass(suggestionNode, 'highlight');
              suggestionNode.firstChild.setAttribute('tabindex', 0);
              suggestionNode.firstChild.focus();
          }