Firefox Nightly is a free and open source daily updated experimental bleeding edge browser from Firefox. It comes with latest innovations features that are still in developments. Only use this version of Firefox for testing purpose.
Install Firefox Nightly on Ubuntu
To install the Firefox Nightly on your system, run the below commands one by one in your terminal application (ctrl+alt+t). It will add the Firefox Nightly PPA on your system and install latest Firefox Nightly on your system.
Note: It will NOT override any other Firefox Stable package.
sudo add-apt-repository ppa:ubuntu-mozilla-daily/ppa
sudo apt update
sudo apt install firefox-trunk
After that you can open using below command or click the Show Apps menu button on Ubuntu dock and search for Nightly in the search menu.
You can also uninstall Firefox Nightly and PPA using below commands.
sudo apt remove --autoremove firefox-trunk
sudo add-apt-repository --remove ppa:ubuntu-mozilla-daily/ppa