anchor.diff:      #xmlelement{name = <<"body">>, attrs=common_attrs(Rid, Sid) ++ [
               {<<"content">>, <<"text/xml; charset=utf-8">>},
               {<<"xmlns:xmpp">>, <<"urn:xmpp:xbosh">>},
  -            {<<"xmpp:version">>, <<"1.0">>},
  +            {<<"xmpp:version">>, Version},
               {<<"hold">>, <<"1">>},
               {<<"wait">>, <<"60">>},
               {<<"xml:lang">>, Lang},
  
positive.code: 
  handle_call(get_transport, _From, State) ->
      {reply, transport(State), State};
  handle_call(stop, _From, #state{url = Socket} = State) ->
      StreamEnd = escalus_stanza:stream_end(),
      send0(transport(State), exml:to_iolist(StreamEnd), State),
      {stop, normal, ok, State}.
  
negative.code:             already_stopped
      end.
  
  upgrade_to_tls(#transport{} = _Conn, _Props) ->
      not_supported.
  
  use_zlib(#transport{} = _Conn, _Props) ->
      not_supported.
  
  get_transport(#transport{rcv_pid = Pid}) ->
      gen_server:call(Pid, get_transport).
  
  