| Release Date | October 19, 2027 |
|---|---|
| Release Owner | Ryan VanderMeulen |
| Corresponding ESR releases | 175.8.0 |
| Nightly cycle length | 2 weeks |
| Beta cycle length | 2 weeks |
| Milestones | |
|---|---|
Deadline to request manual QAQA has been informed via a Jira ticket (Functional, Nimbus/Remote delivery or Embedded QA) about features needing manual testing — more on how to file a Jira ticket here. Test Plans and Cases also require the technical documentation, which should be attached to the ticket. |
September 9 In 46 weeks |
Deadline to request accessibility engineering reviewAccessibility engineering review has been requested (using the |
September 16 In 47 weeks |
Nightly startsThe first day of the cycle is Merge Day. After merging firefox-main to the beta branch, we bump the nightly version number on firefox-main and a new development cycle starts for Firefox. A new Firefox Nightly is shipped every 12 hours. |
September 16 In 47 weeks |
Build ready for QAFeatures with a QA request are ready for testing to assess feature quality and provide a formal test report by the end of Week 2 of the nightly cycle. |
September 23 In 48 weeks |
QA Test Case reviewThe QA team appreciates an earlier sign-off from the project teams. The approval milestone will be the final deadline for any feature Test Plan sign-offs. No feedback/sign-off on QAs Feature Test Plan could result in misalignment on testing scope, incomplete test coverage and invalid bugs. |
September 24 In 48 weeks |
Strings hand-off to engineeringFinal strings are handed off to Engineering to ensure they are landed before localization begins. |
September 27 In 48.5 weeks |
String Freeze startsIn order to ensure that our localizers have adequate time to translate strings, please make sure that all string changes have landed by end of day. |
September 29 In 48.5 weeks |
Nightly QA sign-offQA signs off on new features in Nightly by sharing individual test reports with their quality assessment and reasoning. |
September 29 In 48.5 weeks |
Draft beta release notesA draft document was created and shared internally with stakeholders to prepare our final release notes for general availability. This document initially contains a copy of our public beta release notes shipping the week after and will be enriched during the beta cycle with media and final copy. |
September 30 In 49 weeks |
Merge dayThis is the day in the release cycle when we merge firefox-main into the beta branch. This is the end of the development cycle for Firefox 183 and the beginning of our Beta stabilization cycle. |
September 30 In 49 weeks |
Beta 1First beta of the cycle, rolled out to our beta population. Build starts at 13:00 UTC. Stabilization work via uplifts. |
October 4 In 49.5 weeks |
Beta 2First automated beta of the cycle. It is rolled out to 100% of our beta population. Build starts at 13:00 UTC. |
October 6 In 49.5 weeks |
SUMO content creationUser affecting changes were identified and provided to the support.mozilla.org team. The support content for this release can now be created before release day. |
October 7 In 50 weeks |
Beta 3Build starts at 13:00 UTC. Stabilization work via uplifts. |
October 8 In 50 weeks |
Beta 4Build starts at 13:00 UTC. Stabilization work via uplifts. |
October 11 In 50.5 weeks |
Deadline to request security bug uplifts ESR patches must be readyDeadline for security bugs uplift requests ( |
October 12 In 50.5 weeks |
Beta 5 Last beta upliftsLast beta of the cycle and thus the end of beta uplifts. Build starts at 13:00 UTC. |
October 13 In 50.5 weeks |
Release notes submission deadlineAll release notes for Firefox were added to the draft document or communicated directly with the release manager. Illustrations such as screenshots and videos were provided. Final Release release notes are created by the release manager on firefox.com. |
October 14 In 51 weeks |
Release Candidate Ready for QAThis is the build we intend to ship a week later unless we need to build another Release Candidate to fix a major quality or business critical issue. |
October 14 In 51 weeks |
Release day!Firefox 183 ships at 13:00 UTC (6 AM PT) with an initial 25% rollout. |
October 19 In 51.5 weeks |
Dot release 1Scheduled for one week after launch, this Desktop and/or Android release targets critical quality fixes and selective feature uplifts. The deadline for uplift requests is EOD on the Friday prior to go-live. Should emergency dot releases ship earlier and resolve pending issues, the Release Management team will determine if this scheduled milestone remains necessary. |
October 26 In 52.5 weeks |
| Milestones | |
|---|---|
183.0 branch is createdThe |
October 8 |
183.0 release candidate is createdThe 183.0 release candidate is created based on the |
October 8 |
Preliminary QA sign off on 183.0QA gives a preliminary sign off on 183.0. 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. |
October 11 |
Final QA sign off on 183.0 Release notes readyQA gives its final sign off on 183.0. 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. |
October 12 |
183.0 sent to Apple StoreWe submit 183.0 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. |
October 12 |
183.1 branch is createdThe |
October 15 |
183.1 release candidate is createdThe 183.1 release candidate is created based on the |
October 15 |
183.0 is shipped183.0 is shipped on the Apple Store at 3:00 AM UTC with a phased 7 days rollout: |
October 18 |
Preliminary QA sign off on 183.1QA gives a preliminary sign off on 183.1. 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. |
October 18 |
Final QA sign off on 183.1 Release notes readyQA gives its final sign off on 183.1. 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. |
October 19 |
183.1 sent to Apple StoreWe submit 183.1 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. |
October 21 |
183.1 is shipped183.1 is shipped on the Apple Store at 3:00 AM UTC with a phased 7 days rollout: |
October 25 |