"...The most obvious example is to compare the modern convention of multi-document tab-switching to the buffer-switching mechanisms you see in Emacs. Once you start opening a significant number of tabs, the number of documents you can open and see at the same time is limited by the width of your screen. For Firefox on this machine, the number is twelve[1] when it's running full-screen. Even if you can see every document, the title of each will need to be sharply truncated to fit on the small visible tab, making it harder to identify a tab without switching to it. To find the tab you want, you need to just press control-pageup over and over again..."