Installers and packages

Firefox reaches users in a different form on each platform. This page lists them side by side, with who each one is for and what keeps it up to date. The pages below go into detail for macOS and Linux. Windows installers have their own section: Installer.

macOS
Linux

At a glance

Platform	Form	Built by	Installs into	Updated by
Windows	Stub installer	Mozilla	`Program Files`, or a per-user directory when that isn’t writable	Application Update
Windows	Full installer	Mozilla	`Program Files` by default, configurable	Application Update
Windows	MSI package	Mozilla, wraps the full installer	Same as the full installer	Application Update
Windows	MSIX package	Mozilla	Managed by Windows	The Microsoft Store. The self-hosted MSIX has no update path yet, see How Packaged Builds Update
macOS	Disk image (.dmg)	Mozilla	Wherever the user drags the app, usually `/Applications`	Application Update, with an administrator prompt when the user can’t write to the app (see macOS Elevated Update)
macOS	Installer package (.pkg)	Mozilla	`/Applications`, owned by `root`	Application Update, with an administrator prompt for users outside the `admin` group
Linux	Tarball (.tar.xz)	Mozilla	Any directory	Application Update, when the directory is writable
Linux	.deb package	Mozilla	`/usr/lib/<package name>`	APT, from packages.mozilla.org
Linux	.rpm package	Mozilla	`/usr/lib/<package name>`	`dnf` or `zypper`, from packages.mozilla.org (see the note in Linux)
Linux	Flatpak	Mozilla	Managed by Flatpak	Flathub
Linux	Snap	Canonical, outside mozilla-central	Managed by `snapd`	`snapd`
Linux	Distribution packages	Each distribution	Chosen by the distribution	The distribution’s package manager

“Application Update” is Firefox’s own updater, described in Application Update. On Windows, the Mozilla Maintenance Service lets it update an installation in Program Files without a permission prompt. In builds where something else does the updating, Firefox is meant to turn its own updater off. How Packaged Builds Update explains how, and why Mozilla’s .rpm is an exception today.

Programs that run outside the browser

Some install and update work happens in separate programs:

The updater, which applies an update while Firefox isn’t running. See Update Implementation.
The Mozilla Maintenance Service on Windows, which runs the updater with the permissions it needs.
The background update task on Windows, which can download and apply updates while Firefox is closed. See Background Updates. It doesn’t run on macOS yet (bug 1653435).
helper.exe on Windows, which handles the uninstaller and some post-update steps. See Helper.
The privileged helper on macOS, used for updates that need an administrator. See macOS Elevated Update.
The DMG install helper on macOS, which copies Firefox into /Applications when it’s started from the disk image. See macOS.
The default browser agent on Windows, which reports default browser settings and some install details. See Default Browser Agent.