Milestones and key data for Firefox 153

Release Date	July 21, 2026
Release Owner	Pascal Chevrel
Corresponding ESR releases	153.0.0 · 140.13.0 · 115.38.0^?
Nightly cycle length	4 weeks
Beta cycle length	5 weeks
Bugs fixed in nightly	2569
Uplifts in beta	453 (0 backouts)
Uplifts in RC	3 (0 backouts)
Uplifts in dot releases	0 (0 backouts)
Total number of uplifts	456
Betas	13
Release Candidates	1
Dot releases	0
Release notes	General · Developer · Enterprise

Key Milestones
Nightly start	May 19
Beta start	June 17
153.0 ^{0% adoption - 25% rollout}	July 21
Planned 153.0.x ^{Desktop and Android}	July 28
Planned 153.0.x ^{Desktop and Android}	August 4
Planned 153.0.x ^{Desktop and Android}	August 11

Milestones
153.0 branch is created The `firefox-v153.0` branch is created from the `main` branch. `version.txt` is bumped to 153.1 on `main`. Any further code change for the 153.0 release now requires an uplift request.	July 10
153.0 release candidate is created The 153.0 release candidate is created based on the `firefox-v153.0` branch. This build might contain additional uplifts. Additionaly, the 152.3 release is tagged as shipped.	July 10
Preliminary QA sign off on 153.0 QA gives a preliminary sign off on 153.0. 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.	July 13
Final QA sign off on 153.0 Release notes ready QA gives its final sign off on 153.0. 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.	July 14
153.0 sent to Apple Store We submit 153.0 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.	July 14
153.1 branch is created The `firefox-v153.1` branch is created from the `main` branch. `version.txt` is bumped to 153.2 on `main`. Any further code change for the 153.1 release now requires an uplift request.	July 17
153.1 release candidate is created The 153.1 release candidate is created based on the `firefox-v153.0` branch. This build might contain additional uplifts. Additionaly, the 153.0 release is tagged as shipped.	July 17
153.0 is shipped 153.0 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%.	July 20
Preliminary QA sign off on 153.1 QA gives a preliminary sign off on 153.1. 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.	July 20
Final QA sign off on 153.1 Release notes ready QA gives its final sign off on 153.1. 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.	July 21
153.1 sent to Apple Store We submit 153.1 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.	July 23
153.2 branch is created The `firefox-v153.2` branch is created from the `main` branch. `version.txt` is bumped to 153.3 on `main`. Any further code change for the 153.2 release now requires an uplift request.	July 24
153.2 release candidate is created The 153.2 release candidate is created based on the `firefox-v153.0` branch. This build might contain additional uplifts. Additionaly, the 153.1 release is tagged as shipped.	July 24
153.1 is shipped 153.1 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%.	July 27
Preliminary QA sign off on 153.2 QA gives a preliminary sign off on 153.2. 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.	July 27
Final QA sign off on 153.2 Release notes ready QA gives its final sign off on 153.2. 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.	July 28
153.2 sent to Apple Store We submit 153.2 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.	July 30
153.3 branch is created The `firefox-v153.3` branch is created from the `main` branch. `version.txt` is bumped to 154.0 on `main`. Any further code change for the 153.3 release now requires an uplift request.	July 31
153.3 release candidate is created The 153.3 release candidate is created based on the `firefox-v153.0` branch. This build might contain additional uplifts. Additionaly, the 153.2 release is tagged as shipped.	July 31
153.2 is shipped 153.2 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%.	August 3
Preliminary QA sign off on 153.3 QA gives a preliminary sign off on 153.3. 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.	August 3
Final QA sign off on 153.3 Release notes ready QA gives its final sign off on 153.3. 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.	August 4
153.3 sent to Apple Store We submit 153.3 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.	August 6
153.3 is shipped 153.3 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%.	August 10