anchor.diff:                    globalregistry ->
                         get_json_key(Node, "globalregistry_domains", "globalregistry", CookieKey);
                     cluster_manager ->
  -                      get_json_key(
  -                          Node, ["provider_domains", "cluster_domains"],
  -                          "cluster_manager", CookieKey
  -                      );
  +                      [
  +                          get_json_key(Node, "provider_domains", "cluster_manager", CookieKey),
  +                          get_json_key(Node, "cluster_domains", "cluster_manager", CookieKey)
  +                      ];
                     op_worker ->
                         get_json_key(Node, "provider_domains", "op_worker", CookieKey);
                     cluster_worker ->
                         get_json_key(Node, "cluster_domains", "cluster_worker", CookieKey)
                 end,
  -        case is_list(Key) of
  -            false -> {Node, json_parser:get_value(Key, DescriptionFile, "/")};
  -                _ ->
  -                    %% if Key is a list, choose value that is different that undefined,
  -                    %% there should be only one such value
  -                    fun F([H | T] = Key) ->
  -                        case json_parser:get_value(H, DescriptionFile, "/") of
  -                            undefined -> F(T);
  -                            Value -> {Node, Value}
  -                        end
  +        case AppName of
  +            cluster_manager ->
  +                %% if AppName is cluster_manager, the Key is a list
  +                %% choose value that is different that undefined,
  +                %% there should be only one such value
  +                FilterUndefined = fun F([H | T]) ->
  +                    case json_parser:get_value(H, DescriptionFile, "/") of
  +                        undefined -> F(T);
  +                        Value -> {Node, Value}
                       end
  +                end,
  +                FilterUndefined(Key);
  +            _ -> {Node, json_parser:get_value(Key, DescriptionFile, "/")}
           end
  -    end, Nodes).
  -
  +    end, Nodes).
positive.code: %% Returns list of tuples {Node, Cookie}
  %% @end
  %%--------------------------------------------------------------------
  -spec get_cookies(Nodes::[node()] | [] | undefined , AppName :: string(), CookieKey :: string(),
      DescriptionFile :: string()) -> [{Node :: node(), Cookie :: atom()}] | [].
  get_cookies(undefined, _AppName, _CookieKey, _DescriptionFile) -> [];
  get_cookies([], _AppName, _CookieKey, _DescriptionFile) -> [];
  
negative.code: %% Afterwards, cleans environment by running 'cleanup.py' script.
  %% @end
  %%--------------------------------------------------------------------
  -spec clean_environment(Config :: list(), Apps :: [{AppName :: atom(), ConfigName :: atom()}]) -> ok.
  clean_environment(Config, Apps) ->
      case cover:modules() of
          [] ->
  