Introduction to SeaMonkey

SeaMonkey is a browser suite, a descendant of Netscape. It includes the browser, composer, mail and news clients, and an IRC client.

It is the community-driven follow-on to the Mozilla Application Suite, created after Mozilla decided to focus on separate applications for browsing and e-mail. Those applications are Firefox-102.8.0 and Thunderbird-102.8.0.

This package is known to build and work properly using an LFS 11.3 platform.

Package Information



The tarball seamonkey-2.53.15.source.tar.xz will untar to seamonkey-2.53.15 directory.

SeaMonkey Dependencies


Autoconf-2.13, Cbindgen-0.24.3, GTK+-3.24.36, Python-2.7.18, UnZip-6.0, yasm-1.3.0, and Zip-3.0




If you don't install recommended dependencies, then internal copies of those packages will be used. They might be tested to work, but they can be out of date or contain security holes.


alsa-lib-1.2.8, dbus-glib-0.112, GConf-3.2.6, startup-notification-0.12, Valgrind-3.20.0, Wget-1.21.3, Wireless Tools-29, Hunspell, and Watchman

User Notes:

Installation of SeaMonkey

The configuration of SeaMonkey is accomplished by creating a mozconfig file containing the desired configuration options. A default mozconfig file is created below. To see the entire list of available configuration options (and an abbreviated description of each one), issue ./configure --help. You may also wish to review the entire file and uncomment any other desired options. Create the file by issuing the following command:

cat > mozconfig << "EOF"
# If you have a multicore machine, all cores will be used

# If you have installed DBus-Glib comment out this line:
ac_add_options --disable-dbus

# If you have installed dbus-glib, and you have installed (or will install)
# wireless-tools, and you wish to use geolocation web services, comment out
# this line
ac_add_options --disable-necko-wifi

# Uncomment these lines if you have installed optional dependencies:
#ac_add_options --enable-system-hunspell
#ac_add_options --enable-startup-notification

# Uncomment the following option if you have not installed PulseAudio
#ac_add_options --disable-pulseaudio
# and uncomment this if you installed alsa-lib instead of PulseAudio
#ac_add_options --enable-alsa

# Comment out following option if you have gconf installed
ac_add_options --disable-gconf

# Comment out following options if you have not installed
# recommended dependencies:
ac_add_options --with-system-icu
ac_add_options --with-system-libevent
ac_add_options --with-system-nspr
ac_add_options --with-system-nss
ac_add_options --with-system-webp

# Disabling debug symbols makes the build much smaller and a little
# faster. Comment this if you need to run a debugger. Note: This is
# required for compilation on i686.
ac_add_options --disable-debug-symbols

# The elf-hack is reported to cause failed installs (after successful builds)
# on some machines. It is supposed to improve startup time and it shrinks
# by a few MB - comment this if you know your machine is not affected.
ac_add_options --disable-elf-hack

# Seamonkey has some additional features that are not turned on by default,
# such as an IRC client, calendar, and DOM Inspector. The DOM Inspector
# aids with designing web pages. Comment these options if you do not
# desire these features.
ac_add_options --enable-calendar
ac_add_options --enable-dominspector
ac_add_options --enable-irc

# The BLFS editors recommend not changing anything below this line:
ac_add_options --prefix=/usr
ac_add_options --enable-application=comm/suite

ac_add_options --disable-crashreporter
ac_add_options --disable-updater
ac_add_options --disable-tests

# rust-simd does not compile with recent versions of rust.
# It is disabled in recent versions of firefox
ac_add_options --disable-rust-simd

ac_add_options --enable-optimize="-O2"
ac_add_options --enable-strip
ac_add_options --enable-install-strip
ac_add_options --enable-official-branding

# The option to use system cairo was removed in 2.53.9.
ac_add_options --enable-system-ffi
ac_add_options --enable-system-pixman

ac_add_options --with-system-bz2
ac_add_options --with-system-jpeg
ac_add_options --with-system-png
ac_add_options --with-system-zlib


If you are compiling this package in chroot you must do two things. First, as the root user, ensure that /dev/shm is mounted. If you do not do this, the Python configuration will fail with a traceback report referencing /usr/lib/pythonN.N/multiprocessing/ Run:

mountpoint -q /dev/shm || mount -t tmpfs devshm /dev/shm

Second, either as the root user export the $SHELL environment variable using export SHELL=/bin/sh or else prepend SHELL=/bin/sh when running the ./mach commands.

First remove an obsolete flag in python code, that has been removed in python-3.11:

grep -rl \"rU\" | xargs sed -i 's/"rU"/"r"/'

Next, work around a problem in the Python virtual environment:

sed -i "/if sys.executable !=/i\    open(join(bin_dir, 'pyvenv.cfg'), 'w').close()" \

Next, work around a crash that occurs when playing audio when Seamonkey is compiled with rustc-1.67 or higher:

sed -i '/USE_PULSE_RUST/d' media/libcubeb/src/

Compile SeaMonkey by running the following commands:

export CC=clang CXX=clang++          &&
./mach configure || ./mach configure &&
./mach build

This package does not come with a test suite.

Install SeaMonkey by issuing the following commands as the root user:

./mach install                  &&
chown -R 0:0 /usr/lib/seamonkey &&

cp -v $(find -name seamonkey.1 | head -n1) /usr/share/man/man1

Command Explanations

export CC=clang CXX=clang++: With the introduction of gcc-12, many more warnings are generated when compiling mozilla applications and that results in a much slower, and larger, build. Furthermore, building with GCC on i?86 is currently broken. Although upstream mozilla code defaults to using llvm unless overridden, the older configure code in SeaMonkey defaults to gcc.

./mach configure || ./mach configure: This validates the supplied dependencies and the mozconfig. This is run twice because problems with mach will cause it to fail the first time.

./mach build --verbose: Use this alternative if you need details of which files are being compiled, together with any C or C++ flags being used. But do not add '--verbose' to the install command, it is not accepted there.

./mach build -jN: The build should, by default, use all the online CPU cores. If using all the cores causes the build to swap because you have insufficient memory, using fewer cores can be faster.

Configuring SeaMonkey

For installing various SeaMonkey add-ons, refer to Add-ons for Seamonkey.

Along with using the Preferences menu to configure SeaMonkey's options and preferences to suit individual tastes, finer grain control of many options is only available using a tool not available from the general menu system. To access this tool, you'll need to open a browser window and enter about:config in the address bar. This will display a list of the configuration preferences and information related to each one. You can use the Search: bar to enter search criteria and narrow down the listed items. Changing a preference can be done using two methods. One, if the preference has a boolean value (True/False), simply double-click on the preference to toggle the value and two, for other preferences simply right-click on the desired line, choose Modify from the menu and change the value. Creating new preference items is accomplished in the same way, except choose New from the menu and provide the desired data into the fields when prompted.

If you use a desktop environment like Gnome or KDE you may wish to create a seamonkey.desktop file so that SeaMonkey appears in the panel's menus. If you didn't enable Startup-Notification in your mozconfig change the StartupNotify line to false. As the root user:

mkdir -pv /usr/share/{applications,pixmaps}              &&

cat > /usr/share/applications/seamonkey.desktop << "EOF"
[Desktop Entry]
Comment=The Mozilla Suite

ln -sfv /usr/lib/seamonkey/chrome/icons/default/default128.png \


Installed Programs: seamonkey
Installed Libraries: Numerous libraries, browser, and email/newsgroup components, plugins, extensions, and helper modules installed in /usr/lib/seamonkey
Installed Directory: /usr/lib/seamonkey

Short Descriptions


is the Mozilla browser/email/newsgroup/chat client suite