I upgraded to Firefox 20 and now my inspector is confined to the bottom of the viewport in an iFrame that I can pop out. In previous versions, I could open up the CSS rules and box model visualization at the same time. This was one of the main reasons I considered the Firefox inspector superior to those of Opera, Chrome and Safari. I can't seem to figure out how to do this now.. do I need to click between the box model and the rules or is there some way to revert to the old inspector layout or one that is more like it? I'll code an add-on if I have to get this thing to work. Very disappointed that Firefox removed their old default inspector view.