anchor.diff:      case leo_gateway_rpc_handler:get(Key) of
           %% For the case If-Modified-Since matches timestamp in metadata
           {ok, #?METADATA{timestamp = IMSSec}, _Resp} ->
  -            ?reply_not_modified([?SERVER_HEADER], Req);
  +            {ok, CustomHeaders} = leo_nginx_conf_parser:get_custom_headers(Key, CustomHeaderSettings),
  +            ?reply_not_modified([?SERVER_HEADER] ++ CustomHeaders, Req);
           %% For regular case (NOT a chunked object)
           {ok, #?METADATA{cnumber = 0,
                           meta = CMetaBin} = Meta, RespObject} ->
  
positive.code:     case leo_gateway_rpc_handler:get(Key, CacheObj#cache.etag) of
          %% HIT: For the case If-Modified-Since matches mtime in cache
          {ok, match} when CacheObj#cache.mtime == IMSSec ->
              ?reply_not_modified([?SERVER_HEADER], Req);
  
          %% HIT: get an object from disc-cache
          {ok, match} when Path /= []
  
negative.code: 
          %% MISS: For the case If-Modified-Since matches timestamp in metadata
          {ok, #?METADATA{timestamp = IMSSec}, _Resp} ->
              {ok, CustomHeaders} = leo_nginx_conf_parser:get_custom_headers(Key, CustomHeaderSettings),
              ?reply_not_modified([?SERVER_HEADER] ++ CustomHeaders, Req);
  
          %% MISS: get an object from storage (small-size)
          {ok, #?METADATA{cnumber = 0,
  