Add comments.

Source/MQTTnet.Extensions.WebSocket4Net/WebSocket4NetMqttChannel.cs

@@ -98,7 +98,6 @@ namespace MQTTnet.Extensions.WebSocket4Net
 #else
                     certificates.Add(certificate);
 #endif
-                    
                 }
             }
 

Source/MQTTnet/Client/Options/MqttClientOptionsBuilder.cs

@@ -264,8 +264,7 @@ namespace MQTTnet.Client
 
             return this;
         }
-
-        // TODO: Consider creating _MqttClientTcpOptionsBuilder_ as overload.
+        
         public MqttClientOptionsBuilder WithTcpServer(Action<MqttClientTcpOptions> optionsBuilder)
         {
             if (optionsBuilder == null)

Source/MQTTnet/Client/Options/MqttClientTcpOptions.cs

@@ -19,6 +19,11 @@ namespace MQTTnet.Client
         
         public int BufferSize { get; set; } = 8192;
 
+        /// <summary>
+        /// Gets or sets whether the underlying socket should run in dual mode.
+        /// Leaving this _null_ will avoid setting this value at socket level.
+        /// Setting this a value other than _null_ will throw an exception when only IPv4 is supported on the machine.
+        /// </summary>
         public bool? DualMode { get; set; }
 
         public LingerOption LingerState { get; set; } = new LingerOption(true, 0);

Source/MQTTnet/Client/Options/MqttClientWebSocketOptions.cs

@@ -7,23 +7,23 @@ using System.Net;
 
 namespace MQTTnet.Client
 {
-    public class MqttClientWebSocketOptions : IMqttClientChannelOptions
+    public sealed class MqttClientWebSocketOptions : IMqttClientChannelOptions
     {
-        public string Uri { get; set; }
+        public CookieContainer CookieContainer { get; set; }
+        
+        public MqttClientWebSocketProxyOptions ProxyOptions { get; set; }
 
         public IDictionary<string, string> RequestHeaders { get; set; }
 
         public ICollection<string> SubProtocols { get; set; } = new List<string> { "mqtt" };
 
-        public CookieContainer CookieContainer { get; set; }
-
-        public MqttClientWebSocketProxyOptions ProxyOptions { get; set; }
-
         public MqttClientTlsOptions TlsOptions { get; set; } = new MqttClientTlsOptions();
+        
+        public string Uri { get; set; }
 
         public override string ToString()
         {
             return Uri;
         }
     }
-}
+}

Source/MQTTnet/Client/Options/MqttClientWebSocketProxyOptions.cs

@@ -4,7 +4,7 @@
 
 namespace MQTTnet.Client
 {
-    public class MqttClientWebSocketProxyOptions
+    public sealed class MqttClientWebSocketProxyOptions
     {
         public string Address { get; set; }
 

Source/MQTTnet/Implementations/MqttWebSocketChannel.cs

@@ -118,7 +118,6 @@ namespace MQTTnet.Implementations
 
         void SetupClientWebSocket(ClientWebSocket clientWebSocket)
         {
-
             if (_options.ProxyOptions != null)
             {
                 clientWebSocket.Options.Proxy = CreateProxy();