How to Install Firefox ESR on Ubuntu 26.04, 24.04 and 22.04

Firefox ESR is the predictable Firefox channel to install on Ubuntu when extension compatibility, school systems, kiosk setups, or managed desktops matter more than getting every new browser feature immediately. To install Firefox ESR on Ubuntu through APT, use the Mozilla Team PPA because a stock Ubuntu install does not expose a firefox-esr package candidate.

The Mozilla Team PPA currently provides firefox-esr for Ubuntu 26.04, 24.04, and 22.04. It keeps ESR updates in the normal APT workflow and can run beside Ubuntu’s default Firefox Snap because the ESR package uses its own launcher, binary name, and profile path.

Install Firefox ESR on Ubuntu via Mozilla Team PPA

The Mozilla Team PPA is maintained on Launchpad and provides the firefox-esr APT package alongside other Mozilla packages like Thunderbird on Ubuntu. On a stock Ubuntu install, sudo apt install firefox-esr and sudo apt-get install firefox-esr have no package candidate until this PPA is enabled.

Mozilla also publishes official Linux ESR tarballs on the Firefox ESR download page. Those downloads are useful when you need a specific upstream archive, but they are not an Ubuntu package workflow. The PPA method is easier to update, verify, and remove with APT.

Update Ubuntu System Packages

Open a terminal (press Ctrl+Alt+T or search for “Terminal” in the Activities overview) and refresh the package index:

sudo apt update

Commands prefixed with sudo run with administrative privileges. If your account is not in the sudo group, see the sudoers guide for Ubuntu first.

Then upgrade any outdated packages:

sudo apt upgrade

Import Mozilla Team PPA for Firefox ESR on Ubuntu

A PPA (Personal Package Archive) lets Ubuntu use packages outside the main repositories. The Mozilla Team PPA publishes firefox-esr for the ESR channel. It also publishes a firefox-dev package, but that package contains development files for the standard Firefox build and is not Firefox Developer Edition. The PPA does not publish a firefox-developer-edition package; use the separate Firefox Developer Edition on Ubuntu workflow if you need that browser channel.

Minimal images can also miss the add-apt-repository helper. Install software-properties-common first if the command is not available:

sudo apt install -y software-properties-common

Add the PPA:

sudo add-apt-repository ppa:mozillateam/ppa -y

Refresh the package index so the new packages become visible:

sudo apt update

Check that APT now sees the Firefox ESR package from the PPA:

apt-cache policy firefox-esr

Relevant lines on Ubuntu 26.04 include:

firefox-esr:
  Candidate: 140.10.0esr+build1-0ubuntu0.25.10.1~mt1
        500 https://ppa.launchpadcontent.net/mozillateam/ppa/ubuntu resolute/main amd64 Packages

Ubuntu 24.04 and 22.04 can show a different patch-level candidate while staying on the same ESR branch. The important checks are a non-(none) candidate and a Mozilla Team PPA source line.

Install Firefox ESR with APT on Ubuntu

Install the firefox-esr package with APT. The package also installs xul-ext-ubufox from Ubuntu’s universe component. Standard Ubuntu desktop installs normally have Universe enabled, but minimal or customized systems may need the Ubuntu repository component guide if APT cannot locate that dependency.

sudo apt install -y firefox-esr

The standard Firefox Snap can stay installed. Firefox ESR uses the /usr/bin/firefox-esr binary, the firefox-esr.desktop launcher, and profile data under ~/.mozilla/firefox-esr/, so it stays separate from the default Snap build.

Ubuntu Server and minimal installs can use the same package command, but the browser still needs a graphical session, remote display, or headless browser workflow to open pages. Installing firefox-esr does not add a full desktop environment.

Verify Firefox ESR Installation on Ubuntu

Confirm the installed package state:

dpkg-query -W -f='${db:Status-Abbrev} ${binary:Package} ${Version}\n' firefox-esr

Relevant output starts with ii firefox-esr, followed by the package version installed from your Ubuntu release’s PPA candidate. Then check the browser channel:

firefox-esr --version

The version line starts with Mozilla Firefox and ends with esr, such as Mozilla Firefox 140.10.0esr. The patch number can differ by Ubuntu release while the PPA catches up across series, but the esr suffix confirms the Extended Support Release channel.

Launch Firefox ESR on Ubuntu

Launch Firefox ESR from Terminal

Start Firefox ESR from any terminal:

firefox-esr

Launch Firefox ESR from Ubuntu Applications Menu

Open the Activities overview and select Show Applications. Current packages use the generic desktop name Firefox Web Browser, so use the ESR icon, the firefox-esr command, or the About dialog’s Extended Support Release label to distinguish it from the standard Firefox Snap.

Firefox ESR vs Standard Firefox on Ubuntu

Firefox ESR receives the latest security and stability fixes, but it does not take every new feature from the rapid release channel. Mozilla’s Firefox channel documentation describes standard Firefox as a roughly four-week major release channel, while ESR gets annual major releases with minor and patch updates in between. That tradeoff is the main reason to keep ESR and standard Firefox side by side on Ubuntu.

Release	Update Pattern	Best For
Firefox ESR	Longer major-version cycle, regular security and stability fixes	Managed desktops, schools, kiosks, extension-sensitive workflows
Standard Firefox	Rapid feature releases about every 4 weeks	Latest browser features, developer tools, general browsing

Choose Firefox ESR when critical workflows depend on consistent browser behavior, or when you manage systems for other users who need predictable updates. Standard Firefox is the better pick when you want the newest web technologies and developer tools as soon as Mozilla ships them.

If you still have the default Snap build and want to remove it, remove the Firefox Snap on Ubuntu with the full profile and package cleanup path. For experimental builds, see how to install Firefox Beta or Nightly on Ubuntu.

Manage Firefox ESR on Ubuntu

Set Firefox ESR as Default Browser on Ubuntu

Firefox ESR installs alongside the default Firefox build, so both browsers remain available. Launch the standard browser with the firefox command or its dock icon, and open the ESR build with firefox-esr or its separate desktop entry.

To make Firefox ESR the default for web links, open Settings > Default Applications and choose the ESR browser entry from the Web dropdown. Alternatively, set the default from the terminal:

xdg-settings set default-web-browser firefox-esr.desktop

Revert to the standard build at any time with the matching desktop file:

xdg-settings set default-web-browser firefox.desktop

Update Firefox ESR on Ubuntu

Firefox ESR updates arrive through APT alongside your regular system updates. To update only Firefox ESR without upgrading every package:

sudo apt update && sudo apt install --only-upgrade -y firefox-esr

If no newer version is available, APT reports that firefox-esr is already at the latest version.

Remove Firefox ESR from Ubuntu

Remove the Firefox ESR package first:

sudo apt remove -y firefox-esr

Preview orphan cleanup before removing anything else. Continue only if the list contains packages you expected to remove, such as xul-ext-ubufox, and not unrelated kernels or desktop packages you still need.

sudo apt autoremove --dry-run

If the preview is clean, run the real cleanup interactively:

sudo apt autoremove

If you no longer need other packages from the Mozilla Team PPA (such as Thunderbird), remove the repository and refresh APT:

sudo add-apt-repository --remove ppa:mozillateam/ppa -y

sudo apt update

Ubuntu 22.04 can leave the PPA key in /etc/apt/trusted.gpg.d/ after the source is removed. Run this only when you are fully done with the Mozilla Team PPA:

sudo rm -f /etc/apt/trusted.gpg.d/mozillateam-ubuntu-ppa.gpg /etc/apt/trusted.gpg.d/mozillateam-ubuntu-ppa.gpg~

Confirm the package is no longer installed with an installed-state check:

dpkg-query -W -f='${db:Status-Abbrev} ${binary:Package}\n' firefox-esr 2>/dev/null | grep '^ii' || echo "firefox-esr is not installed"

Expected output:

firefox-esr is not installed

Then confirm APT no longer has a PPA candidate for Firefox ESR:

apt-cache policy firefox-esr

Relevant lines include:

firefox-esr:
  Installed: (none)
  Candidate: (none)

Removing the package does not delete your bookmarks, passwords, history, or extensions. Firefox ESR stores user data in ~/.mozilla/firefox-esr/ and cached files in ~/.cache/mozilla/firefox-esr/. Delete those directories only if you are sure you no longer need the data.

Conclusion

Firefox ESR is installed on Ubuntu from the Mozilla Team PPA, with APT handling updates while the ESR branch keeps major-version changes slower and more predictable. The standard Firefox Snap can stay beside it, or you can follow the dedicated cleanup path to remove the Firefox Snap on Ubuntu. For experimental builds, use the separate guide to install Firefox Beta or Nightly on Ubuntu.