We were told that Firefox 19 would include Australis UI. The new theme has been made for creating a smooth and streamlined appearance across all the platforms Firefox supports, from Android and Linux to OS X and Windows 8.
Firefox 19 nightly build has been updated with Australis UI but it doesn't look as good in Windows 8 as it looks in Windows 7. 
Firefox's Australis UI in Windows 7:
Firefox's Australis UI in Windows 8:
↧
Firefox 19 Australis UI looks terrible in Windows 8
↧