Overall, vertically, the title bar and address bar now take almost a dozen pixels more than previous Firefox releases, which steals very precious vertical space.

The compact density option for the address bar is now gone, and not only that, the title bar is now a lot taller than before. The most substantial redesign, which is being prepared for the next release, called Proton, promises to drive most power users away because it's broken on a number of levels and makes using the browser a very unpleasant experience. Google Chrome and Apple Safari look almost the same as they did a decade ago. Seeing that, someone at Mozilla probably decided that the best way to entice people back is by changing its UI, thus Firefox has already seen quite a huge number of changes despite other major web browsers staying relatively the same in terms of their visuals i.e. Tashkinov writes: Over the past ten years, Firefox market share has decreased substantially and the web browser has lost its appeal and coolness.