mozilla.debian.net now is updated, but...

[BubuXP]

... there is still something to fix.

1) all the command lines begin with a $ but a regular user cannot
install or update packages. All the lines should begin with #

2) the 'release' version for testing can be found in the unstable
repository at the moment. But simply adding the unstable repos in
/etc/apt/source.list will update all the installed packages to the
unstable version. The instructions should mention that one must add a
file (the filename is not important) in /etc/apt/preferences.d/ with
the following text:

Package: *
Pin: release a=unstable
Pin-Priority: 100

This way the unstable repo will works like the experimental and the
backports repos.