It explains that Firefox ESR delivers a stable, long‑term supported browser for Ubuntu users who need consistency over the bleeding‑edge releases. The guide walks you through adding Mozilla’s PPA, updating apt, installing firefox‑esr, and removing any conflicting Snap version to ensure the system uses the correct binaries. For enterprise environments it even shows how to pin the package so updates are controlled, and verifies installation by checking the About dialog for the ESR label. Finally, it reminds readers to keep the browser current with regular apt upgrades while enjoying reliable security patches without experimental features.

How to Install Firefox ESR on Ubuntu 22.04 or 20.04

If you’ve ever watched your internal web app hiccup after a fresh OS update, chances are you’ll want the long‑term support (LTS) version of Firefox that sticks around longer and doesn’t get the newest experimental features until they’re battle‑tested. That’s what Firefox ESR is all about.

Why Go ESR Instead of the Default Browser?

• It ships with security patches but not every new feature, which means fewer surprises for apps that depend on a stable API.
• IT departments love it because you can pin the version and keep hundreds of machines uniform.
• On Ubuntu 20.04 or 22.04, the stock firefox package is the bleeding‑edge 80/100 series—good for general browsing but not always what you need in an enterprise setting.

I once helped a coworker in IT who had to run a proprietary internal site that broke when Firefox added CSS Grid support. Switching to ESR saved the day and kept everyone on the same page.

What You’ll Need

• A machine running Ubuntu 20.04 LTS or 22.04 LTS.
• Administrative rights (you’ll use sudo).

No special hardware, no fancy tools—just a terminal window.

Adding Mozilla’s PPA

Ubuntu doesn’t ship Firefox ESR in its default repos, so the easiest way is to add Mozilla’s Personal Package Archive:

sudo add-apt-repository ppa:mozillateam/ppa

Why this matters? The PPA hosts the official ESR builds that Microsoft and Canonical don’t bundle by default. Once you’re on it, apt will know where to find the right binaries.

Updating Package Lists

sudo apt update

You might wonder why we bother with a fresh update after adding a repo. Think of it as refreshing your phone’s contacts: without it, apt would still be pointing at old metadata and could install something else by mistake.

Installing Firefox ESR

sudo apt install firefox-esr

That’s all there is to it. The package manager pulls the latest ESR (currently 97 as of this writing) and installs it in /usr/lib/firefox/.

If you already had a version of Firefox installed via Snap, you’ll want to remove it first:

sudo snap remove firefox

Snap’s firefox is a separate app that won’t get overridden by the apt install. Removing it keeps your system from confusing which browser to launch.

Pinning the Package (Optional)

If you’re on an IT network that runs automated updates, you might want to prevent firefox-esr from jumping to a newer ESR version without your approval:

echo "Package: firefox-esr" | sudo tee /etc/apt/preferences.d/firefox-esr.pref
echo "Pin: release *" | sudo tee -a /etc/apt/preferences.d/firefox-esr.pref
echo "Pin-Priority: 1001" | sudo tee -a /etc/apt/preferences.d/firefox-esr.pref

This tells apt to treat the ESR package as a top‑priority candidate, so it won’t be replaced unless you explicitly ask for an upgrade.

Verifying the Install

Open Firefox and go to Help => About Firefox. You should see something like “Firefox 97 (ESR)”. If you still see a different number, double‑check that Snap was removed or that no other firefox package is installed.

What Next?

With ESR running smoothly, you can now rely on consistent security patches while avoiding the wild card of feature releases. Keep an eye on Mozilla’s release notes for any critical updates—just run:

sudo apt update && sudo apt upgrade firefox-esr

…and you’re good to go.