Firefox Hacks [Electronic resources] نسخه متنی

Hack 94. Run Multiple Mozilla Browsers

Run as many Mozilla browsers as you want on
your single desktop.

Unless you're extremely technical, Internet Explorer
6 is a one-shot affair: either you install it once or you
don't install it at all. Firefox is not like that;
you can install many versions and related products and pick between
them as you see fit. There remain one or two combinations to avoid,
as we'll point out in this hack.

9.5.1. Running Different Browsers Simultaneously

To run the Mozilla Application Suite, Camino, Galeon, Compuserve,
Netscape, or Epiphany on the same computer as Firefox, just install
both products in separate directories. You can run both products at
once. You can do that with Firefox and Thunderbird as well, or with
Firefox and Nvu, or with Firefox and Komodo. However, there is one
combination to
avoid.

Mozilla-based browsers do not yet fully support profile sharing
between products. Firefox and Thunderbird are a partial exception,
since they overlap only in a few profile files, such as the
certificate database. If you run two Mozilla products that use the
standard profile system and the same profile, it's
possible, but not likely, that you will corrupt the profile if you
make extensive configuration changes. You could lose your bookmarks
and other content.

To solve this problem, use the -CreateProfile
command-line option to create a separate profile for each product.
Change shortcuts and menu items so that they call each product with
the -Profile
profilename option.

Some of the information stored by Firefox is not used by the Mozilla
Application Suite, and vice versa. Bookmark detail and some RDF
information are two examples. In general, starting the wrong product
against a given profile is fairly harmless; the extra, unknown
information will simply be ignored. For Firefox 1.0, there have been
few changes or no changes in the file formats of common profile
files. Read the release notes for future versions to see if planned
changes to the profile system have taken place yet.

9.5.2. Running Two Separate Versions of Firefox

As in the previous case, you can install two separate versions of
Firefox and alternate between them. By default, you
can't run them in parallel on Windows. However,
there's no problem doing so on Unix/Linux. Here are
two sources of unwanted behavior:

On Windows, if you start Firefox version A while Firefox version B is
already running, all you get is another version B browser window.

Running a nightly or debug version of Firefox [Hack #92] always carries a small risk.
Think carefully before running such a version with a profile or
desktop that contains important long-term information.

Nightlies and debug versions are mostly used for testing, and
it's possible to construct tests that destroy the
only displayed browser window without also shutting down Firefox.
That leaves the browser running invisibly in memory as though it were
a server. It then has to be found and killed by hand. If
you're running several versions of Firefox, this
behavior can be a major source of confusion. It's
another good reason to treat nightlies with care.

9.5.3. Running Two Instances of Firefox Simultaneously on Windows

The problem of two simultaneous versions of Firefox on Windows can be
solved with simple hacks. Once one (or more) installation of Firefox
is hacked, you can run two (or more) separate instances. You can do
so even if the two instances are the same version.

h5

Window users who use one instance of Firefox as their main browser
and wish to debug another instance can do so with an environment
variable. Simply set the environment variable
MOZ_NO_REMOTE=true to run the two Firefoxes
simultaneously (see bug 131805). Put this variable in
c:\autoexec.bat or equivalent.

9.5.3.2 Permanent solution

To put this hack in place, first grab a free Windows executable
editor, such as Resource Hacker (http://www.users.on.net/johnson/resourcehacker/)
or Resource Explorer (http://www.wilsonc.demon.co.uk/d7resourceexplorer).

Next, locate the Firefox binary firefox.exe in
the install area. Open it with your editor and drill down to the
102 and 103 entries in the
StringTable section. Change these values to an
alternate value, such as Myfirefox. Figure 9-1 shows this section of the resource fork of the
binary.

Figure 9-1. Unique instance names inside the Windows Firefox binary

Save the changes: choose Compile Script and select
FileSave. Now you're ready to start up the
modified Firefox. Just run it as normal.

9.5.4. Running Only One Instance of Firefox on Unix/Linux

On these platforms, the problem is rather the reverse of Windows: by
default, any command-line invocation of Firefox will start a whole
new browser instance. You can get around that, too.

Quite often, nonbrowser programs have to open web pages. An example
is when the user clicks a Help link. Those programs would rather that
such pages display in the user's currently opened
browser than start a whole new browser instance.

On Unix/Linux, Firefox supports an xremote feature
to make this possible. It allows you to configure these other
programs to drive Firefox in a programmatic way. This can have an
effect different from defaults offered in the preferences. For
example, another program can instruct Firefox to use a new tab for
the required page if there is a current Firefox instance already
running, or else launch Firefox and open the required page if
it's not running. The following script does so:

#!/bin/sh
mozilla-xremote-client -a firefox "openURL($1,new-tab)" || firefox "$1"

The mozilla-xremote-client binary (provided on
Unix/Linux by default) is a small tool provided with the standard
Unix/Linux Firefox install.

If, for example, you save the preceding script as a file named
openlink and give it executable permissions, you
can then configure other programs to run it as required:

openlink "http://www.mozilla.org"

Other options possible with this script are noted here: http://www.mozilla.org/unix/remotel.
Beware that this page is slightly out of date;
mozilla-xremote-client is the correct tool to
use.