Australis is the name of the new default Firefox theme that Mozilla has been working on for quite some time. The decision was made to release the update gradually, with some updates already in the browser, while others still waiting to be delivered to it. One of the next Australis-related updates comes in Firefox 19. You may have already seen how the new tab bar will look like in mock-ups that Mozilla designer Stephen Horlander released a while ago.

The new tab strip or style will ship with Firefox 19 if development runs along smoothly. You’ll immediately notice the soft curves around the active tab that connect to the tab bar. Mozilla wants to do away with the rectangular shaped tabs that current implementations of Firefox use.

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