Ubuntu – How to install Iceweasel in Ubuntu 15.04

You should not do this, because versions of Firefox past the 3.6-series do not remain supported, even with security updates, when new versions come out. (This is why Firefox 8 is in Lucid now.) Continuing to run Firefox 7.0.1 means you are running a version that has known security vulnerabilities that are not and never will be patched--it puts you (and your customers/clients, if applicable) at risk.

Install the upstream binaries manually

Unless you can get one of the above techniques to work, the easiest way would probably be to make your script download the upstream Firefox 7.0.1 binary distribution, unpack it, and install it as root:

[ -d /opt ] || sudo mkdir -m  755 /opt
cd /opt
if [ `uname -m` = x86_64 ]
then
    sudo wget http://mirror.dacentec.com/mozilla/firefox/releases/7.0.1/linux-x86_64/en-US/firefox-7.0.1.tar.bz2
else
    sudo wget http://mirror.dacentec.com/mozilla/firefox/releases/7.0.1/linux-i686/en-US/firefox-7.0.1.tar.bz2
fi
sudo tar xjf firefox-7.0.1.tar.bz2
sudo apt-get purge firefox # removes firefox; comment out if definitely uninstalled
ln -s /opt/firefox/firefox /usr/bin/firefox

A few considerations:

1. As explained above, you should not do this at all! (This technique is useful for other purposes, which is the main reason I'm posting about it.)

2. The script above doesn't check to see whether or not commands completed successfully before proceeding. It assumes that /opt exists with reasonable permissions or that it doesn't exist and can be created (which is pretty safe), that the download succeeds (which is not particularly safe), and that the archive successfully unpacks (which is somewhat safe, if the download succeeded). It also assumes that if you don't have a 64-bit PC (or Intel Mac), then you have a 32-bit PC (or Intel Mac), since the script would fail anyway for other architectures since binary builds are not provided upstream for them (you can still build from source for them though); while this is safe in the sense that it doesn't increase the risk of failure, it doesn't give any useful error message when the architecture is unsupported. It creates a symbolic link to the newly installed Firefox 7.0.1 binary in /usr/bin, which will fail if you still had another version of Firefox installed, but you would want it to fail in that situation.

3. There is no reason to think the download mirror I have used in the script is the best one for you. You might want to change it, or implement the script to figure out a reasonable mirror to download from. (If you apply this technique as I am recommending--that is, only to a similar but different problem where the software you're installing is still supported with security updates--then you'll be installing a different program and will thus have to change the argument to wget anyway.)

4. Using this method, you don't have to hold the firefox package, because the firefox package is not what is providing Firefox 7.0.1. (No package is providing it; it's installed manually without the package manager.)

Since mixing Debian and Ubuntu is not generally recommended, I've tried (and succeded) to do it manually.

The Iceweasel package details page (http://packages.debian.org/squeeze/iceweasel) has links to download pages for different architectures, as well as a list of dependencies and suggested packages.

In my case, I go to the i386 architecture download page, where there are links to download the file from different mirrors. You can simply click on one of the links or copy it to run from a terminal:

wget -c http://ftp.mx.debian.org/debian/pool/main/i/iceweasel/iceweasel_3.5.16-20_i386.deb

Before installing the downloaded package, you need to make sure you have all dependencies installed. Any of the solutions provided here will do.

In my particular case, I had to download and install xulrunner-1.9.1 and several of its dependencies: libhunspell-1.2-0, libjpeg62, and libmozjs2d. Each can be found at the link provided with the dependencies list.

Then, install everything (I show separated commands to reduce lenght of example):

sudo dpkg -i libhunspell-1.2-0_1.2.11-1_i386.deb libjpeg62_6b1-1_i386.deb libmozjs2d_1.9.1.16-20_i386.deb
sudo dpkg -i xulrunner-1.9.1_1.9.1.16-20_i386.deb iceweasel_3.5.16-20_i386.deb

NOTE: Iceweasel "takes over" your current firefox configuration, and you will not be able to run both Iceweasel and Firefox at the same time. Note the creation of the symbolic link firefox.real during installation (it links to /usr/lib/firefox/firefox.sh):

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On first run, it will check and install (or reject) the add-ons from your Firefox:

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And this is Iceweasel up and running on my Ubuntu 12.04:

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