new HttpClient().DefaultRequestHeaders.Accept.Clear();
new HttpClient().DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("text/plain");
var handler = new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.GZip };
var httpClient = new HttpClient(handler)
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("text/plain"));