Thunderbird 91.4.0 can not connect to imap server

[Linshiqi]

Thank you for this great project.

Problem

When I use thunderbird version 91.4.0 to connect imap server via tls port 993, the thunderbird show a error dialog saying that tls sharkhand error happened.

Code related

TCP_ServerSession.cs

internal bool Start(TCP_ServerSession owner)
            {
                ...
                try{
                    m_pSslStream = new SslStream(m_pTcpSession.TcpStream.SourceStream,true);
                    var sslProtocols = SslProtocols.Tls |  SslProtocols.Tls11 | SslProtocols.Tls12 | SslProtocols.Tls13;

                    // After below code executed, the thunderbird show that error
                    m_pSslStream.BeginAuthenticateAsServer(m_pTcpSession.m_pCertificate, false, sslProtocols, false, this.BeginAuthenticateAsServerCompleted, null);
                }
                catch (Exception x){
                    m_pException = x;
                    SetState(AsyncOP_State.Completed);
                }
                ...
            }