Comment by mrb

I think this is a terrible idea from a usability standpoint. Why reinvent windows in CSS? Desktop browsers can already open multiple pages in multiple windows. And it's all neatly integrated in my OS where I can use keyboard shortcuts to maximize, minimize, close, move windows, or place the windows on multiple monitors, etc.

It's as much a bad idea as websites trying to reinvent scrollbars. No thanks. I prefer to use my native windows and scrollbars.