Inspecting websocket traffic with proxy
Found the answer myself in case anyone is interested (source is blogs.telerik.com)
WebSockets
Fiddler’s HTML5 WebSockets support continues to grow; Fiddler extensions can now capture and manipulate WebSocket messages by handling the FiddlerApplication.OnWebSocketMessage event.
In preparation for a full-featured WebSockets UI, Fiddler no longer spews WebSocket messages to the Log tab. If you’d like to re-enable that behavior until the full UI is available, you can do so using FiddlerScript. Simply click Rules > Customize Rules and add the following function inside your Handlers class.
static function OnWebSocketMessage(oMsg: WebSocketMessage) {
// Log Message to the LOG tab
FiddlerApplication.Log.LogString(oMsg.ToString());
/*
// Modify a message's content
var sPayload = oMsg.PayloadAsString();
if (sPayload.Contains("time")) {
oMsg.SetPayload(sPayload + "... bazinga!");
}
*/
}