Web Browser in WPF not displaying when AllowTransparency =true

Hi ,

I have requirement to display a web page in WPF and the WPF window should be transparent.
To achieve this I am using a webbrowser control , inside the Window.

But when I set AllowTransparency =true ,ResizeMode="NoResize" ,Background="Transparent , the content of the web browser are not displayed .

If somebody has come across this issue , Please share your inputs.