Firefox 4 still has a huge number of UI issues on linux due to reliance on XUL for the UI. There have been improvements in a couple extensions, as far as font c

Firefox 4 still has a huge number of UI issues on linux due to reliance on XUL for the UI. There have been improvements in a couple extensions, as far as font colors using GTK themes go, but the menubar is still too tall and has the wrong font color (on basically every GTK theme and theme engine I can find) and keyboard shortcuts for several things (e.g. space to toggle menu items without closing the menu) are removed from GTK. Using RGBA with the murrine GTK engine, alpha transparency leaves "ghosts" on hovered menu options in Firefox, and buttons occasionally completely change their look pre- and post-hover (firebug had a drop-down that would "segment" itself when hovered, for example). Add this to the completely non-native tabs and toolbar, and the lack of a status bar, and the UI is simply unusable imo. A native UI using an established toolkit, or a custom-built UI with usability in mind would both be preferable to the current halfway kludge.