Using development builds of Firefox Nightly

Using Firefox Nightly as my default web browser lets me test the Firefox development changes every day. Firefox Nightly is built from the latest code changes in mozilla-central repository every night. You can learn more about Mozilla Firefox development builds here.

If you are interested to participate in Firefox development, it is good start to use Firefox Nightly or building Firefox from the sources. You can report new bugs you spot in development builds of Firefox Nightly. You can find simple bugs to fix and test new patches.

In this blog post, I'll explain how to install Firefox Nightly and run multiple version of Firefox on gnu/Linux computer. These instructions will also apply to other operating systems. You might need to substitute the paths to Firefox program to match your operating system.

If you are using Mozilla Ubuntu Daily PPA, You can remove those PPA packages safely with 'ppa-purge' command.

 $ sudo ppa-purge ppa:ubuntu-mozilla-daily/ppa

Firefox Nightly on gnu/Linux

Download the Firefox Nightly for gnu/Linux from nightly.mozilla.org. Uncompress the tar.bz2 archive to a directory on your computer. I usually place my programs in /opt/ partition, but you can choose any different directory.

Here is the Firefox Nightly program path /opt/Firefox-Nightly/firefox on my computer. Make sure you have write permission to your Firefox Nightly directory, otherwise you'll have problems while installing the nightly updates.

You can now launch Firefox Nightly using following command /opt/firefox-nightly/firefox -P --no-remote . The -P option starts the Mozilla Profile Manager and --no-remote starts a new instance of Firefox.

Next lets set Firefox Nightly as the default browser with update-alternatives program, this program makes changes to symlinks on Debian/Ubuntu operating systems.

sudo update-alternatives --install /usr/bin/gnome-www-browser gnome-www-browser /opt/firefox-nightly/firefox 10


$ sudo update-alternatives --config gnome-www-browser 
There are 5 choices for the alternative gnome-www-browser (providing /usr/bin/gnome-www-browser).

  Selection    Path                          Priority   Status
------------------------------------------------------------
  0            /usr/bin/google-chrome         200       auto mode
  1            /opt/firefox-nightly/firefox   10        manual mode
  2            /usr/bin/chromium-browser      40        manual mode
  3            /usr/bin/epiphany-browser      85        manual mode
* 4            /usr/bin/firefox               40        manual mode
  5            /usr/bin/google-chrome         200       manual mode

Press enter to keep the current choice[*], or type selection number: 1
update-alternatives: using /opt/firefox-nightly/firefox to provide /usr/bin/gnome-www-browser (gnome-www-browser) in manual mode.

# Launch Firefox Nightly and choose your default profile.
$ /opt/firefox-nightly/firefox -P --no-remote 

For other operating system, read How to make Firefox default on support.mozilla.org website.

How to run multiple Firefox Browsers

If you want to use multiple versions of Firefox at the same time. For example, You want to use Firefox Nightly along side the Firefox Stable version or test a localized version of Firefox for your language.

Open your system terminal and launch Firefox with following command firefox -P --no-remote and choose a different profile for this instance of Firefox.

You can learn more about Firefox Profiles here on Multiple Firefox Profiles page on Mozilla Developer Network (MDN).

Have fun testing Mozilla Firefox Nightly! Don't forget to report bugs and send patches!