A while back, the Firefox 2012 roadmap was announced and it included quite a few important changes, some of which are already available in the latest Firefox Nightly.
A few days ago, a Firefox Nightly update finally introduced a new built-in download panel which is displayed on the top right and shows the time remaining until the download finishes:
But this is just one of the new features presented in the 2012 roadmap which are already available in the latest Firefox Nightly. There's no new default theme yet, but for instance, the new tab page is already available for quite some time (with some improvements to the initial release):
There's also a new home page (has been available in Nightly for a while) which lets you quickly access the downloads, bookmarks, history, addons, sync and settings:
And finally, there's also a built-in HTML5 PDF viewer:
If you're not using Firefox Nightly and want to use the build-in Firefox PDF viewer, you can get the extension from HERE.
Install Firefox Nightly in Ubuntu
Firefox Nightly can be installed in Ubuntu, side-by-side with Firefox stable, beta or aurora (it will not overwrite any of these Firefox versions). To add the official Firefox Nightly PPA and install it in Ubuntu, use the commands below in a terminal:
sudo add-apt-repository ppa:ubuntu-mozilla-daily/ppa sudo apt-get update sudo apt-get install firefox-trunk
Debian users can use a repository to test Firefox and Thunderbird development builds - see http://mozilla.debian.net/ .
For other Linux distributions, Windows, Mac OSX or Android, you can download Firefox Nightly from HERE.