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The best for a Mac?.
I loved it. Looks very elegant and not boring and stuffy like what you are stuck with on Safari. Pity it could not be had for Safari as Firefox is giving me a few minor niggles. This theme with the colourful tabs improves the look of the browser loads. Never found any glitches using it.
Pros: Looks real good. As far as I can tell, no glitches. Tabs etc. stand out clearly.
Cons: So far, glad to say, none