How to use GraphQL.Client to subscribe to GraphQL API using the same WebSocket subprotocol as the server ?

[phimend]

I successfully created a subscription to a GraphQL API using ClientWebSocket, but I would like to use GraphQL.Client to realize the subscriptions.

Here is a simple example of a subscription that works using ClientWebSocket.:

                client.Options.ClientCertificates.Add(pCertificate);
                client.Options.SetRequestHeader("Sec-WebSocket-Extensions", "permessage-deflate;client_max_window_bits");
                client.Options.SetRequestHeader("Sec-WebSocket-Protocol", "graphql-transport-ws");
                await client.ConnectAsync(pEndpoint, CancellationToken.None);
                var initMessage = new
                {
                    type = "connection_init",
                    payload = new
                    {
                        Authorization = pToken
                    }
                };
                await SendMessageAsync(client, initMessage);

                var subscription = new
                {
                    id = "1",
                    type = "subscribe",
                    payload = new
                    {
                        httpMultipartParams = new
                        {
                            includeCookies = false,
                            requestQueryPlan = false,
                            showTraces = false,
                            abortSignalRef = new { }
                        },
                        operationName = "dataFeed",
                        query = @"
                            subscription dataFeed { 
                                dataFeed {
                                    name
                                    city
                                }
                            }",
                        variables = new { }
                    }
                };

                await SendMessageAsync(client, subscription);

                await ReceiveMessageAsync(client);

I tried to do the same with GraphQL.Client but I still get the error: “Connection closed by the server.”

at GraphQL.Client.Http.Websocket.GraphQLHttpWebSocket.<>c__DisplayClass36_0`1.b__3(Exception e) in /_/src/GraphQL.Client/Websocket/GraphQLHttpWebSocket.cs:line 215

After many try, here is my last example code using GraphQL.Client that still give me the same error (the code is running inside a thread that is still alive):

       GraphQLHttpClientOptions options = new GraphQLHttpClientOptions
        {
            UseWebSocketForQueriesAndMutations = false,
            WebSocketProtocol = WebSocketProtocols.GRAPHQL_TRANSPORT_WS,
            EndPoint = pEndpoint,
            ConfigureWebsocketOptions = (opt) =>
            {
                opt.ClientCertificates.Add(pCertificate);
                opt.SetRequestHeader("Sec-WebSocket-Extensions", "permessage-deflate;client_max_window_bits");
            },
            ConfigureWebSocketConnectionInitPayload = (graphQLHttpOptions) =>
            {
                return new
                {
                    Authorization = pToken
                };
            },
            
        };

        GraphQLHttpClient graphQLClient = new GraphQLHttpClient(
            options,
            new NewtonsoftJsonSerializer()
        );

        GraphQLRequest grapQLSubscription = new GraphQLRequest
        {
            Query = @"subscription dataFeed { 
                                dataFeed {
                                    name
                                    city
                                }
                            }",
            OperationName = " dataFeed "
        };

        var subscriptionResponse = graphQLClient.CreateSubscriptionStream<dynamic>(grapQLSubscription);

        var subscription = subscriptionResponse.Subscribe(
            onNext: res =>
            {
                Console.WriteLine(res.Data.rid);
            },
            onError: error =>
            {
                Console.WriteLine(error.Message);
            },
            onCompleted: () =>
            {
                Console.WriteLine("End subscription");
            }
            );

I am using .Net Framework 4.8
Did I miss something?
Do you have any idea what I'm doing wrong?