Soft code freeze for Firefox 120 starts on October 19 @ 8am UTC

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Ryan VanderMeulen

Oct 16, 2023, 2:03:59 PM10/16/23
to Firefox Dev,

With Firefox 119 in the Release Candidate phase this week, we are nearing the end of the Nightly 120 cycle

In order to avoid invalidating the testing we get out of late Nightly and to ensure that we can roll out Beta 120 to a wider audience with confidence next week, we'd like to ask that any risky changes be avoided from Thursday, October 19 until after the version bump to 121 on October 23.

Also, please be advised that string freeze for Firefox 120 begins Friday, October 20. In order to ensure that our localizers have adequate time to translate strings, please make sure that all string changes have landed by EOD Friday.

Some reminders for the soft code freeze period:

- Be ready to back out patches that cause crash spikes, new crashes, severe regressions
- Monitor new regressions and escalate merge blockers
- Support release management by prioritizing fixing of merge blockers

Do Not:
- Land a risky patch or a large patch
- Land new features (that affect the current Nightly version) — be mindful that code behind NIGHTLY_BUILD or RELEASE_OR_BETA ifdefs can lead to unexpected CI results
- Flip prefs that enable new Features that were untested in the Nightly cycle
- Plan to kick off new experiments that might impact a feature's merge readiness

Please let us know if you have any questions/concerns.

Ryan VanderMeulen
Firefox Release Manager

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Dianna Smith

Oct 23, 2023, 10:57:16 AM10/23/23
to Ryan VanderMeulen, Firefox Dev,

The 121 version bump has landed on mozilla-central and the soft freeze is over.

Dianna Smith
Firefox Release Manager
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