title: TRestClient 406 Not Acceptable error in Delphi Sydney 10.4 (Works in Delphi Seattle XE10)
body: <p>I'm trying to run a project of mine in Delphi Sydney 10.4.1 however it is erroring out with the error:</p>
  <p>Project raised exception class EHTTPProtocolException with message 'HTTP/1.1 406 Not Acceptable'.</p>
  <p>The same project works fine in Delphi Seattle. It's only broken since building in Delphi 10.4 Sydney</p>
  <p>The code I am using is:</p>
  <pre><code>
  var
    RESTClient: TRESTClient;
    RESTRequest: TRESTRequest;
    RESTResponse: TRESTResponse;
    JSONMensaje: TJsonObject;
    JSONResponse: TJsonObject;
    param: TRESTRequestParameter;
  begin
    try
      RESTClient := TRESTClient.create(nil);
      RESTRequest := TRESTRequest.create(nil);
      JSONMensaje := TJsonObject.create(nil);
      RESTResponse := TRESTResponse.create(nil);
      try
        RESTRequest.Response := RESTResponse;
        RESTClient.Params.Clear;
        RESTRequest.Client := RESTClient;
        RESTRequest.Params.Clear;
        RESTRequest.ClearBody;
  
        RESTRequest.Method := TRESTRequestMethod.rmPOST;
        RESTClient.BaseURL := POSTURL;
  
        RESTRequest.AddBody(TkData.ToJSON, ctAPPLICATION_JSON);
  
        RESTClient.ContentType := 'application/json';
  
        param := RESTClient.Params.AddItem('Accept', 'application/json');
        param.Kind := pkHTTPHEADER;
  
        param := RESTClient.Params.AddItem('Authorization', 'Bearer ' + Token);
        param.Kind := pkHTTPHEADER;
        param.Options := [poDoNotEncode];
  
        RESTRequest.Execute;  // &lt;&lt; EHTTPprotocolException with message 'HTTP/1.1 406 Not Acceptable
  ...
  </code></pre>
  <p>Just wondering if anyone could point me in the right direction please?</p>