As may already read, Mozilla has enhanced its Firefox Browser’s Private Browsing, creating a new “tracking protection” option that prevents websites from learning the user’s behaviour.
For now, this features is implemented only on the Aurora (Pre-Beta) branch, but the function will be added to the stable branch soon.
The latest aurora/alpha/pre-beta version available is Firefox 42 Aurora, recently released.
Up to date packages are available via the Firefox Aurora PPA, so installing the aurora version of the internet browser on Ubuntu is easy. Just add the PPA to your system, update the local repository index and install the firefox package:
$ sudo add-apt-repository ppa:mozillateam/firefox-next
$ sudo apt-get update
$ sudo apt-get install firefox
Optional, to remove firefox, do:
$ sudo apt-get remove firefox
The installation instructions should work on Ubuntu 15.04 Vivid Vervet, Ubuntu 14.04 Trusty Tahr, Ubuntu 12.04 Precise Pangolin, Linux Mint 17.2 Rafaela, Linux Mint 17.1 Rebecca, Linux Mint 17 Qiana, Linux Mint 13 Maya, Pinguy OS 14.04, Elementary OS 0.3 Freya, Elementary OS 0.2 Luna, Deepin 2014, Peppermint 6, Peppermint 5, LXLE 14.04 and Linux Lite 2.