"Firefox is a great browser. However, it's a tad on the bloated side (even though the new version are definitely better!). Also, Firefox is focused on cross-platform compatibility. That's great, but sometimes that also means that Firefox won't be able to take advantage of Gnome-specific features, including the unified look, better language support, and HIG-compliant settings. If you've been feeling these Firefox blues as well, Epiphany could be the answer.
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"So is Epiphany right for you? Well, maybe. You should probably be using Ubuntu, not Kubuntu, Xubuntu (or the other derivatives). You should also probably prefer ease-of-use and simplicity over power (not that Epiphany doesn't have power). And you also have to accept that Epiphany won't have as many add-ons as Firefox, although there are a lot. If you're OK with all of the above, Epiphany is a great option."