// Show the current status of read stream.
    procedure ReadingResponse(const Size: Int64; Stream: TStream); virtual;
(...)
procedure TFPCustomHTTPClient.ReadResponse(Stream: TStream; Const AllowedResponseCodes : Array of Integer; HeadersOnly: Boolean = False);
(...)
  Len: Int64;
begin
(...)
      Repeat
        LB:=ReadBufLen;
        If (LB>L) then
          LB:=L;
        R:=Transfer(LB);
        ReadingResponse(Len, Stream);
        L:=L-R;
      until (L=0) or (R=0);
      end
    else if L<0 then
      begin
      // No content-length, so we read till no more data available.
      Repeat
        R:=Transfer(ReadBufLen);
        ReadingResponse(Len, Stream);
      until (R=0);
(...)