Random Firefox UI observations:
- Tabs have been redesigned to look like buttons. Why? Surely altering the appearance of an interface component or control to reflect something it isn't is basic UX 101? And why remove the outline of non-selected tabs? Isn't "affordance" of components also UX 101?
- Themes: Isn't one of the goals for a web browser to minimise the "chrome" (the toolbars, tabs, status bar) so that as much of the browser page is visible? Theming a thin toolbar strip seems a bit pointless. (It's pointless in Chrome too, why copy them?)