Does this help the cause?

It can't show anything behind the window, unless the web browser has the option to display the web site's background as transparent. Many browsers have the option for user styles, and as such can replace the background (or other elements) with custom designs, but no browser that I know of can selectively make parts of the page transparent to display what's underneath the window. There are solutions to make the whole window transparent, but that obviously is just that - the whole window, including title bar (the Windows Vista/7 title bar would become more transparent), toolbar(s), page, scrollbar, and anything else in it.