code: function (elements) {
        if (elements.length === undefined) {
          elements = [ elements ]
        }
  
        return liveElements.filter(function (e) {
            return elements.indexOf(e.element) !== -1
        }).length === elements.length
      }
docs: The `enabled` method checks if the live-counting functionality is bound
  to an element.
  
  @param   {Node}     element  All elements that should be checked for the
  Countable functionality.
  
  @return  {Boolean}  A boolean value representing whether Countable
  functionality is bound to all given elements.