As'Salamu Aleykum
I got that many new Linux users get problem while installing Firefox as Iceweasel is built-in in Kali Linux
Below are the Commands to Uninstall Iceweasel and Install Firefox
So here we start now with Installing Firefox in kali Linux 2.0
Open Terminal and Type the following command and hit Enter One by One
apt-get remove iceweasel
echo -e "\ndeb http://downloads.sourceforge.net/project/ubuntuzilla/mozilla/apt all main" | tee -a /etc/apt/sources.list > /dev/null
apt-key adv --recv-keys --keyserver keyserver.ubuntu.com C1289A29
apt-get update
apt-get install firefox-mozilla-build
The Above Commands will install Firefox in your Linux system.
Once Firefox has been installed, you might need Flash player.
To install flash-player Addon, open Terminal and enter the Commands given below
apt-get install flashplugin-nonfree
update-flashplugin-nonfree --install
