ESR Landing Process

REPOS

The ESR repos can be found at https://github.com/mozilla-firefox/firefox/tree/esr140, for example, firefox-esr140 See ESR on whattrainisitnow for the current supported ESR version.

More info about the ESR

• https://support.mozilla.org/kb/firefox-esr-release-cycle
• https://www.firefox.com/browsers/enterprise/
• Download

What should land on firefox-esr

Security and some major stability fixes when landed/merged onto firefox-beta, or fixes for regressions specific to the ESR. In the first few cycles of ESR we may be more flexible on these criteria. As the versions progress we limit this to security and high severity stability fixes.

Exception: If patches only make changes to tests, test harnesses, or anything else that does not affect the shipped builds, they may land with self approval (use a=testonly, a=npotb etc).

The associated flags

approval-mozilla-esrX: ?, +, -

tracking-esrX: ?, -, 150+, 151+, ...

status-esrX: ?, unaffected, wontfix, affected, fixed, verified

esrX is the ESR version supported.

The process

1. When an engineer believes that a stability bug or a security fix needs to be addressed for the ESR: Set status-firefox-esrX to affected. If there is more than one ESR version currently supported, then only set the relevant ESR versions as affected.
2. When the patch is ready for uplift follow the standard Uplift Request Process
3. The Release Management team will monitor and process uplift requests during the Beta cycle of the corresponding mainline Firefox release.

ESR Timeline and Activities

See Release Checklist Documentation for more details.

Release Announcement Email

Subject: Firefox ESR 115.12.0 released

We are pleased to announce that the Firefox ESR 115.12.0 release is now available for download at:
https://www.mozilla.org/firefox/organizations/all/

As always, we recommend that users keep up to date with the newest version
of Firefox ESR for the latest stability and security fixes.

Release notes for Firefox 115.12.0esr are available at:
https://www.firefox.com/firefox/115.12.0/releasenotes/

Associated security advisories are posted at:
https://www.mozilla.org/security/advisories/mfsa2024-26/

Thank you,
<name>
Firefox Release Manager