CustomExceptionForRayGun.cs

void Main()
{
	var exception = new JsException("testing message", "stack\ntrace\nhere");		
	var rayGun = new RaygunClient(();
	rayGun.SendInBackground(exception);
	
	
	Console.WriteLine(exception.ToString());
	/*
		expecting to see this : 
		
		testing message
		stack
		trace
		here
	     
	        but instead see this:
	        
	        testing message
	        none
	*/	
}

public class JsException : Exception
{
   private readonly string _stack;
   public JsException(string message, string stack = null)
       : base(message)
   {
       _stack = stack;
   }

   public override string StackTrace
   {
       get { return _stack; }
   }

   public override string ToString()
   {
       if (string.IsNullOrWhiteSpace(_stack))
       {
           return base.ToString();
       }

       return Message + Environment.NewLine + _stack;
   }
}