Read CONTINUATION frame with Flutter

Question

I have a sensor which sends data in a continuous stream in CONTINUATION frames within a http communication. As example a Wireshark protocol using a Firefox browser is here: https://i.stack.imgur.com/GD047.png. `` When I use the Flutter package http e.g.:

 _client = http.Client();
Uri uri = Uri.parse('http://192.168.178.84:1456');
var request = http.Request(
  "GET",
  uri,
);
Future<http.StreamedResponse> response = _client.send(request);
try {
  response.asStream().listen((streamedResponse) {
    streamedResponse.stream.listen((data) {
      var result = asciiDecoder.convert(data);
      print(result);
    });
  });
} catch (e) {
  print("Caught $e");}

I get '[ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: Invalid response line' as soon as the sensor sends the first 'continuation' frame. As I am not familiar with http, can anybody help me reading 'continuation' frames?