Firefox Hacks [Electronic resources] نسخه متنی

Hack 25. Migrate Firefox Profiles

Move user data between separate Firefox
installations or between separate versions.

Welcome to complexity. Every piece of software
has an Achilles heel, and Firefox's is the tangle of
issues that surround its user profiles. Moving profiles is tricky,
and you have to be careful. Fortunately, it's a
well-established problem and all that's required is
excessive care. There are plans afoot to simplify all of this in a
future, minor version. But for now, moving complete Firefox profiles
is difficult for numerous reasons:

Use of absolute pathnames in some configuration files causes problems.

Some pathnames aren't portable across Windows, Unix,
and Macintosh.

Profiles are constrained to obey operating system conventions on all
platforms.

Some features were completed only recently, after protracted
investigation.

There are numerous deployment variations, all of which have to be
catered for.

Security requirements for salted directory names [Hack #11] make life
harder.

Some information is stored outside profiles in registry files
(registry.dat, mozver.dat,
and the Windows Registry on Windows, registry on
Unix).

Preferences customized at the platform level can affect profiles
[Hack #23] .

There are at least three ways to effect a partial escape from these
problems:

The Windows-only solution is to use MozBackup (http://mozbackup.jasnapaka.com/), a small
backup tool that copies the web browsing state information
only (history, bookmarks, etc.). It's a
simple copy approach that requires new profiles at each target
installation before restoring the data.

The second escape hatch is to experiment with server-oriented profile
tools [Hack #28] .

The third option is to simplify matters with desalted profiles [Hack #11] .

Before proceeding to the details, here are two things to keep in mind:

Never share one profile between two separate running instances of
Firefox.

The Mozilla registry (registry.dat on Windows)
records the locations of all profiles.

3.5.1. Migrating Between Identical Platforms

If two computers have the same operating system version and the same
users, and the users' home directories have the same
paths, then the whole profile area can simply be copied from one
computer to the other. Mozilla registry files must be copied as well.
On the target computer, replace the local profile with the copied
one. Do the same for the registry files. Since the target computer
already has Firefox installed, the Windows Registry should not need
updates.

Even if the two versions of the Mozilla or Firefox installs are
identical, the profile might behave differently after migration. This
can happen if one or both platform installs has been
customized so that default preferences are not
the same on both [Hack #23] . The
profile will notice these different defaults at runtime but will not
record them anywhere.

3.5.2. Migrating Between Mozilla Versions

Firefox can read all the
profile information of any older
Mozilla-based versions. Examples are beta versions of Firefox, the
Mozilla Application Suite, and Netscape Versions 4.x-7.x. To read
that early information, Firefox must either migrate it (a formal,
one-time process undertaken at install time), import it (in the case
of bookmarks and address books) or read copies of it in place. The
Firefox GUI can drive all but the last option.

You can read copies in place only for browsers based on Mozilla 1.x
or later. To do so, identify the name of an existing Mozilla profile
(default is the default name) and the directory of
the same name that is at the top of the profile data. Write down the
parent directory of that directory. Hand-delete (ideally move to one
side) the Mozilla registries for the old version. Install Firefox,
creating new registries. Start Firefox with the Profile Manager [Hack #10] and create a new profile with
the same name as the old Mozilla profile. Select Choose Folder and
enter the noted folder name. The profile will forever be stored under
the older Mozilla folders, but it will be usable by Firefox.

There is no way to stop a new install of Firefox from automatically
migrating an existing profile when it first starts up, but forced
migration leaves the original profile undamaged. You can choose the
destination profile of the migration using these preferences
(modifying the migration process), or hand-delete the new profile
after migration (undoing the effects of migration), or both:

profile.migration_behavior   /* 0 = default = put in "Profiles" */
profile.migration_behavior   /* 1 = leave in Netscape 4.x profile */
profile.migration_behavior   /* 2 = use specified directory  */
profile.migration_directory  /* absolute path to new profile */

Since no profile exists that includes these preferences, a special
hack is required. Find the all.js file in the
Firefox install area, and insert the wanted options there. Use the
pref() function rather than user_pref().

3.5.3. Migrating Between Different Operating System Versions

Migration between
Unix versions and Unix platforms is trivial. Delete the
~/.mozilla and registry files on the new OS.
Copy the old ~/.mozilla folder and registry
files to the new OS. If $HOME also changes, use a
parallel technique to the following procedure recommended for
Windows.

Under Windows, the main migration difficulty is crossing the gap from
Versions 95/98/98SE/ME/NT3/NT4 to Versions 2000/XP. The former
versions use filesystem paths that are different from the ones used
by the latter versions, and some hand conversion is required. On the
older host, note these strings:

The full pathname of the salted directory for the profile to be
migrated

The profile name

Now, migrate the preferences. Make a copy of the
prefs.js file from the old profile and save it.
Install Firefox on the new OS and make a profile of the same name as
the old one. Close Firefox. Note the full pathname of the salted
directory in the new profile. Open the old preference file and change
all instances of the old salted full pathname to the new salted full
pathname. Change all mail. preferences to match
those in the new preference file exactly and save. Overwrite the new
preference file with the modified old one.

Finally, copy all other files from the old salted directory to the
new one. Start Firefox to confirm the profile has migrated correctly.

Recent versions use the shorthand notation [ProfD]
to describe the path to the topmost directory. This increases
portability in simple cases, but it can yield some bizarre paths on
Windows if files outside the current profile's top
folder are referenced:

[ProfD]../../../../some/other/file.dat

It is possible to use the one profile under two versions of Windows
on a dual-boot computer (or under VMware). Boot into the Windows
version where Firefox already exists. Note the path to the profile
required. Reboot into the other Windows version. Install Firefox with
the same profile name, and pick Choose Folder when you create the
profile. Choose the folder of the profile used under the other
Windows version.

3.5.4. Migrating Between Different Operating System Users

This migration operates in the same way as the last
one. Care is
required to get all hardcoded paths in the preference files correct.
Firefox doesn't care much who the current operating
system user is, except for the purposes of NTLM on Windows. When
copying files from user to user, ensure that the right ownership and
protections are granted.

On Windows, if you change your username and then log out and log back
in as that new user, Firefox won't recover the
profile of the old user and won't start up properly.
To fix that, start Firefox with a profile creation option [Hack #10] . After the new profile is
created, shut Firefox down and migrate the old profile to the new one
[Section 3.5.1, earlier in this
hack].

3.5.5. Migrating Between Windows and Linux

There is currently no simple way to achieve this end, other than to
copy profile information file-by-file from
Windows to Linux. In the case
of the preference files, each line of those files must be checked for
operating-system-specific paths and modified as required.