Milestones and key data for Firefox 149

Release Date	March 24, 2026
Release Owner	Pascal Chevrel
Corresponding ESR releases	140.9.0
Nightly cycle length	6 weeks
Beta cycle length	4 weeks
Bugs fixed in nightly	2954
Uplifts in beta	261 (0 backouts)
Uplifts in RC	1 (0 backouts)
Uplifts in dot releases	0 (0 backouts)
Total number of uplifts	262
Betas	10
Release Candidates	1
Dot releases	0
Release notes	General · Developer · Enterprise

Key Milestones
Nightly start	January 13
Beta start	February 25
149.0 ^{23% adoption - 100% rollout}	March 24
Potential Android 149.0.x	March 31
Planned 149.0.x ^{Desktop and Android}	April 7

Milestones
149.0 branch is created The `firefox-v149.0` branch is created from the `main` branch. `version.txt` is bumped to 149.1 on `main`. Any further code change for the 149.0 release now requires an uplift request.	March 13
149.0 release candidate is created The 149.0 release candidate is created based on the `firefox-v149.0` branch. This build might contain additional uplifts. Additionaly, the 148.3 release is tagged as shipped.	March 13
Preliminary QA sign off on 149.0 QA gives a preliminary sign off on 149.0. If it is green, we push the build to the External Beta Testers group. Otherwise, the dev team fixes the issues reported by QA, uplift them to the release branch and we build another Release Candidate.	March 16
Final QA sign off on 149.0 Release notes ready QA gives its final sign off on 149.0. If the sign off is red, the dev team fixes the issues reported by QA, uplift them to the release branch and we build another Release Candidate.	March 17
149.0 sent to Apple Store We submit 149.0 for review to the Apple Store. If we don`t have a working build by the end of the day, we may not ship this week.	March 17
149.1 branch is created The `firefox-v149.1` branch is created from the `main` branch. `version.txt` is bumped to 149.2 on `main`. Any further code change for the 149.1 release now requires an uplift request.	March 20
149.1 release candidate is created The 149.1 release candidate is created based on the `firefox-v149.0` branch. This build might contain additional uplifts. Additionaly, the 149.0 release is tagged as shipped.	March 20
149.0 is shipped 149.0 is shipped on the Apple Store at 3:00 AM UTC with a phased 7 days rollout: Monday: 1%, Tuesday: 2%, Wednesday: 5%, Thursday: 10%, Friday: 20%, Saturday: 50%, Sunday: 100%.	March 23
Preliminary QA sign off on 149.1 QA gives a preliminary sign off on 149.1. If it is green, we push the build to the External Beta Testers group. Otherwise, the dev team fixes the issues reported by QA, uplift them to the release branch and we build another Release Candidate.	March 23
Final QA sign off on 149.1 Release notes ready QA gives its final sign off on 149.1. If the sign off is red, the dev team fixes the issues reported by QA, uplift them to the release branch and we build another Release Candidate.	March 24
149.1 sent to Apple Store We submit 149.1 for review to the Apple Store. If we don`t have a working build by the end of the day, we may not ship this week.	March 26
149.2 branch is created The `firefox-v149.2` branch is created from the `main` branch. `version.txt` is bumped to 149.3 on `main`. Any further code change for the 149.2 release now requires an uplift request.	March 27
149.2 release candidate is created The 149.2 release candidate is created based on the `firefox-v149.0` branch. This build might contain additional uplifts. Additionaly, the 149.1 release is tagged as shipped.	March 27
149.1 is shipped 149.1 is shipped on the Apple Store at 3:00 AM UTC with a phased 7 days rollout: Monday: 1%, Tuesday: 2%, Wednesday: 5%, Thursday: 10%, Friday: 20%, Saturday: 50%, Sunday: 100%.	March 30
Preliminary QA sign off on 149.2 QA gives a preliminary sign off on 149.2. If it is green, we push the build to the External Beta Testers group. Otherwise, the dev team fixes the issues reported by QA, uplift them to the release branch and we build another Release Candidate.	March 30
Final QA sign off on 149.2 Release notes ready QA gives its final sign off on 149.2. If the sign off is red, the dev team fixes the issues reported by QA, uplift them to the release branch and we build another Release Candidate.	March 31
149.2 sent to Apple Store We submit 149.2 for review to the Apple Store. If we don`t have a working build by the end of the day, we may not ship this week.	April 2
149.3 branch is created The `firefox-v149.3` branch is created from the `main` branch. `version.txt` is bumped to 150.0 on `main`. Any further code change for the 149.3 release now requires an uplift request.	April 3
149.3 release candidate is created The 149.3 release candidate is created based on the `firefox-v149.0` branch. This build might contain additional uplifts. Additionaly, the 149.2 release is tagged as shipped.	April 3
149.2 is shipped 149.2 is shipped on the Apple Store at 3:00 AM UTC with a phased 7 days rollout: Monday: 1%, Tuesday: 2%, Wednesday: 5%, Thursday: 10%, Friday: 20%, Saturday: 50%, Sunday: 100%.	April 6
Preliminary QA sign off on 149.3 QA gives a preliminary sign off on 149.3. If it is green, we push the build to the External Beta Testers group. Otherwise, the dev team fixes the issues reported by QA, uplift them to the release branch and we build another Release Candidate.	April 6
Final QA sign off on 149.3 Release notes ready QA gives its final sign off on 149.3. If the sign off is red, the dev team fixes the issues reported by QA, uplift them to the release branch and we build another Release Candidate.	April 7
149.3 sent to Apple Store We submit 149.3 for review to the Apple Store. If we don`t have a working build by the end of the day, we may not ship this week.	April 9
149.3 is shipped 149.3 is shipped on the Apple Store at 3:00 AM UTC with a phased 7 days rollout: Monday: 1%, Tuesday: 2%, Wednesday: 5%, Thursday: 10%, Friday: 20%, Saturday: 50%, Sunday: 100%.	April 13