Turns out that there is this little application called "Preferred Applications" and you can set your default browser there. I figured this out, 2 minutes after posting my question. Well, three things are a mystery to me:
- Why was my default changed?
- How is a "new" user supposed to know about this "Preferred Applications" utility? This utility is not in the launcher, and I only recalled it by sheer luck.
- Why are the settings within Firefox and within Google Chrome not working?
There can be some packages that depend on (or recommend) a browser, in the form of a virtual package (firefox provides the virtual packages www-browser, iceweasel and gnome-www-browser) or through an alternative (some package depends on firefox | chromium-browser).
To solve your problem you can use aptitude that provides more choices to as to proceed. The package aptitude is not installed by default, so you need to install it
sudo apt-get install aptitude
then you can do
aptitude --simulate remove firefox
and see what it suggests. This is what it says on my system
enzotib@laptop:$ aptitude --simulate remove firefox
The following packages will be REMOVED:
firefox
0 packages upgraded, 0 newly installed, 1 to remove and 19 not upgraded.
Need to get 0 B of archives. After unpacking 30.6 MB will be freed.
The following packages have unmet dependencies:
icedtea-plugin: Depends: firefox (>= 4.0~b7) but it is not going to be installed. or
chromium-browser but it is not going to be installed. or
epiphany-browser but it is not going to be installed. or
midori but it is not going to be installed.
firefox-globalmenu: Depends: firefox (= 5.0+build1+nobinonly-0ubuntu0.11.04.2) but it is not going to be installed.
firefox-gnome-support: Depends: firefox but it is not going to be installed.
The following actions will resolve these dependencies:
Remove the following packages:
1) firefox-globalmenu
2) firefox-gnome-support
3) icedtea-plugin
4) icedtea6-plugin
Leave the following dependencies unresolved:
5) totem-mozilla recommends epiphany-browser | www-browser
6) ubuntu-desktop recommends firefox
7) ubuntu-desktop recommends firefox-gnome-support
8) moonlight-plugin-mozilla recommends firefox | abrowser | iceweasel | xulrunner-1.9.2
9) ubuntu-restricted-addons recommends icedtea6-plugin
10) xul-ext-ubufox recommends firefox (>= 4.0~b6) | abrowser (>= 4.0~b6)
11) mozilla-libreoffice recommends iceweasel | firefox | iceape-browser | konqueror-nsplugins
Accept this solution? [Y/n/q/?]
This way you can see removing firefox what packages breaks. If you choose n, another possible solution is suggested, ans so on.
When you have a best understanding of the problem, and you have selected your way, run aptitude without the --simulate option.
Best Answer
If uninstalling firefox installs epiphany, then that's because some other package depends on "a web browser", which packages do by depending on the virtual package
www-browser. If the google-chrome package doesn't have aProvides: www-browserline, and you have no other browser installed, APT thinks it needs to install a package that does provide awww-browserand then Epiphany is the first choice on a GNOME system.I downloaded one of the Google Chrome .deb files and I can confirm that they don't provide
www-browser. If you want to get this fixed you need to file a bug report with Google and tell them to fix their .deb packages.