code: function updateFilter() {
              if (angular.isFunction(lxSelect.resetDropdownSize)) {
                  lxSelect.resetDropdownSize();
              }
  
              if (angular.isDefined(lxSelect.filter)) {
                  lxSelect.matchingPaths = lxSelect.filter({
                      newValue: lxSelect.filterModel
                  });
              } else if (lxSelect.choicesViewMode === 'panes') {
                  lxSelect.matchingPaths = lxSelect.searchPath(lxSelect.filterModel);
                  _closePanes();
              }
  
              if (lxSelect.autocomplete) {
                  lxSelect.activeChoiceIndex = -1;
  
                  if (lxSelect.filterModel) {
                      LxDropdownService.open('dropdown-' + lxSelect.uuid, '#lx-select-selected-wrapper-' + lxSelect.uuid);
                  } else {
                      LxDropdownService.close('dropdown-' + lxSelect.uuid);
                  }
              }
  
              if (lxSelect.choicesViewMode === 'panes' && angular.isDefined(lxSelect.matchingPaths) && lxSelect.matchingPaths.length > 0) {
                  var longest = _getLongestMatchingPath();
                  if (!longest) {
                      return;
                  }
  
                  var longestPath = longest.split('.');
                  if (longestPath.length === 0) {
                      return;
                  }
  
                  angular.forEach(longestPath, function forEachPartOfTheLongestPath(part, index) {
                      _openPane(index, part, index === (longestPath.length - 1));
                  });
              }
          }
docs: Update the filter.
  Either filter the choices available or highlight the path to the matching elements.