I'm building a small web app that should run in the background while the user browse the web,
a dynamically added Iframe isn't an option since I can't reload it anytime the user refresh or switch page.  

while on Google Chrome this is pretty easy to accomplish, I can't find anywhere an example or documentation on how to implement that on Firefox

I guess what I'm really after is a method to open a non depended totally chrome-less frame (which will run my web app and stays there even if the users switch or refresh pages)

Any Ideas?