RichText Debugger Visualizer Gone wrong

Question

Since I do a lot of debugging with Rich Text manipulations, I decided to write a simple "RTF Debugger Visualizer" which looks like this

#region Namespaces
using System;
using System.Diagnostics;
using System.Drawing;
using System.Windows.Forms;
using Microsoft.VisualStudio.DebuggerVisualizers;
using RtfVisualizer;
#endregion

[assembly: DebuggerVisualizer(
    typeof (RTFDebuggerVisualizer),
    typeof (VisualizerObjectSource),
    Target = typeof (String),
    Description = "RTF Visualizer")]
namespace RtfVisualizer
{
    public class RTFDebuggerVisualizer : DialogDebuggerVisualizer
    {
        protected override void Show(IDialogVisualizerService windowService,
                                     IVisualizerObjectProvider objectProvider)
        {
            string rtf = (String) objectProvider.GetObject();
            Form form = new Form();
            form.Text = "RTF Visualizer";

            form.FormBorderStyle = FormBorderStyle.SizableToolWindow;
            form.Size = new Size(600, 400);
            RichTextBox richTextBox = new RichTextBox();
            richTextBox.Rtf = rtf;
            richTextBox.Dock = DockStyle.Fill;
            richTextBox.Parent = form;
            windowService.ShowDialog(form);
        }
    }
}

But the Visualizer shows the Rtf without formatting as if it's loading the plain text.

For example:

Something like this -

Looks like this -

Test RTF:

{\rtf1\ansi\ansicpg1252\deff0\deflang1033{\fonttbl{\f0\froman\fprq2\fcharset0 Times New Roman;}{\f1\fnil\fcharset0 Microsoft Sans Serif;}}
{\colortbl ;\red255\green0\blue0;\red0\green0\blue255;}
\viewkind4\uc1\pard\cf1\b\f0\fs36 Hell\cf0\b0\fs24  \i Oh \i0 ! \cf2\b World\b0  \cf0\f1\fs17\par
}

I did debug the visualizer - it is receiving the the correct(valid) Rich Text.

What am I missing ? Why does Rich Text look like plain text inside the visualizer ?

Thanks in advance! :)