private async Task HandleIncomingRequests6(CancellationToken ct)
        {
            while (!ct.IsCancellationRequested)
            {
                var tcpClient = await _tcpListener6.AcceptTcpClientAsync();

                var request = new HttpServerRequest(_scheduler, tcpClient, _localPort);
                request.Init(() => _requests.Remove(request), ct2 => HandleRequest(ct2, request));
                _requests.Add(request);
            }
        }