code: function getByGroup(group) {
      var arr = [];
      for (var i = 0; i < CTX.thumbnails.length; i++) {
        if (getAttr(CTX.thumbnails[i], _const_dataattr + '-group') === group) {
          arr.push(CTX.thumbnails[i]);
        }
      }
      return arr;
    }
docs: Get thumbnails by group
  @param  {String} group
  @return {Object}       Array containing the thumbnails