Your script works great...I put a image in instead of text and it does what I was hoping but how can I get rid of the pop-up that asks if the person wants to close the window?
Thanks for the positive feedback on my extension. Unfortunatley it's impossible to get rid of this popup as it is a browser security feature that stops malicious code from closing windows without the users permission.
If you have created a javascript window and you then apply the close window object to this you will not get the warning, becuase you created the window, and so you have permission to close it. :)