There are some major memory/cpu/responsiveness wins on image heavy pages.improved page load times by not decoding images that aren't visible.
Phoronix: Mozilla Firefox 26 Is Shipping Today With Fun Features
Mozilla Firefox 26.0 will be officially released today and with it comes a number of changes and enhancements while right now you can already download this new release...
h.264 support is done through Gstreamer 0.10. Gstreamer 1.0 patches are under review, but on hold while they fix a few regressions. Gstreamer 1.0 bug: https://bugzilla.mozilla.org/show_bug.cgi?id=806917
I'm pretty sure this is not the first version of firefox in linux with h.264 support.On the end-user side, the Linux version of Firefox 26 supports H.264 video codec support in conjunction with the appropriate GStreamer plug-ins.
Geez! That darn thing takes me more than 90 minutes to compile on my Gentoo laptop! (Core 2 Duo T9400, 2.53 GHz.) Only [Libre/Open]Office with more than 4 hours takes more time! I remember the good days it took less than half an hour just a few years ago on the same machine...
BTW anyone knows what will happen with native notifications??