anchor.diff:  handle_request(<<"PUT">>, Req, State)      -> handle_headers(Req, State);
   handle_request(<<"DELETE">>, Req, State)   -> handle_headers(Req, State);
   handle_request(<<"OPTIONS">>, Req0, State) ->
  +	Hs = allow_headers(cowboy_req:header(<<"access-control-request-method">>, Req0)),
   	Req1 = cowboy_req:set_resp_header(<<"access-control-allow-methods">>, <<"HEAD, GET, PUT, DELETE">>, Req0),
  -	Req2 = cowboy_req:set_resp_header(<<"access-control-allow-headers">>, <<"Authorization, Cache-Control, Content-Type, Range">>, Req1),
  +	Req2 = cowboy_req:set_resp_header(<<"access-control-allow-headers">>, cow_http_hd:access_control_allow_headers(Hs), Req1),
   	Req3 = cowboy_req:set_resp_header(<<"access-control-allow-credentials">>, <<"true">>, Req2),
   	{ok, cowboy_req:reply(200, Req3), State};
   handle_request(_, Req, State) ->
   	{ok, cowboy_req:reply(405, Req), State}.
   
   handle_headers(#{method := Method, headers := Hs} =Req, State) ->
  -	try with_headers(allow_headers(Method), Hs) of
  +	try with_headers(allow_riaks2_headers(Method), Hs) of
   		S2headers ->
   			handle_params(Req, State#state{s2reqopts = #{headers => S2headers}})
   	catch
  
positive.code: 			<<"HEAD">> -> riaks2c_object:head(S2pid, Bucket, Key, S2reqopts, S2opts);
  			<<"GET">>  -> riaks2c_object:get(S2pid, Bucket, Key, S2reqopts, S2opts)
  		end,
  	Req1 =
  		try handle_read_stream(Hmod, Bucket, Key, Params, S2pid, Ref, ?REQUEST_TIMEOUT, Req0)
  		catch T:R ->
  
negative.code: 		{ok, Val} ->
  			try Validate(Val) of
  				_ -> with_headers(T, Headers, [{Key, Val}|Acc])
  			catch _:_ -> error({bad_http_header, Val}) end;
  		_ ->
  			with_headers(T, Headers, Acc)
  	end;
  