Firefox 23 Released with Sharing, Mixed Content Blocking and Network Monitor
Beyond that, one of the key additions is mixed content blocking, which (when enabled), protects users from "man-in-the-middle attacks and eavesdroppers on HTTPS pages." There's also a new options panel for Web Developer Toolbox, new social share functionality and most everything else is tweaked from Firefox 22 to ensure better performance all around. Naturally, security fixes are at the heart of the overhaul, so it's definitely worth downloading if you haven't already. Check out the release notes for additional details if you like as well.
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