I would love this feature. I think it would be specially helpfull when having extra displays. This way you could have a complete view of the design panel in one display, and the other tools in other display. This way you could also have a better view of the code in HTML panel.
I was reading the Ideas, and as long as I read, I couldn't find this request... Anyway I'm glad that this request was made before. I'm also hoping this is on the backlog.