*This a shorter summary; if you need more details see this blog post <https://medium.com/@georg.fritzsche/data-preference-changes-in-firefox-58-2d5df9c428b5>.*
As part of the Photon UI refresh, the Firefox data preferences were streamlined. Previously we had two data controls for historic reasons, but now: - There is just one control for data upload for Firefox, which is on by default. - Individual measurements are now collected from either all users or prerelease users. So for Firefox we now just differentiate between “release data” and “prerelease data”. *(For some specific features or studies there may still be explicit opt-in notifications, but this covers all standard Firefox data collection.)* As detailed in another post <https://blog.mozilla.org/futurereleases/2017/09/06/data-just-living/>, this doesn’t change anything about the type of data being collected while it makes the data controls less confusing. However, it does have some technical consequences for Telemetry that we landed in Firefox 58. What does this mean for me? While this has broader technical impact on Firefox data collection, the changes we landed should make this work mostly seamless. For *Firefox users*, there is no significant change; the data upload setting users chose is respected as before. The opt-in for additional Telemetry data went away; instead we always collect less data on Firefox release. For most *Firefox development*, nothing should change. Telemetry takes care of doing the right thing for histograms, scalars & events internally. Local builds from current mozilla-central should default to recording all the prerelease data but not upload it, without any extra build flags. *about:telemetry* allows you to confirm that. For testing locally how release Telemetry behaves, there is a hidden pref: *toolkit.telemetry.testing.overridePreRelease* <https://firefox-source-docs.mozilla.org/toolkit/components/telemetry/telemetry/internals/preferences.html#testing> . For *Fennec development*, nothing changed. Fennec still has the same Telemetry behavior and preference handling as before. For *writing Firefox tests*, *nsITelemetry.canRecordExtended* can be used to check whether prerelease data is recorded. The pref *toolkit.telemetry.testing.overridePreRelease* can be used for tests that need to enable prerelease behavior. For *QAing Firefox data collection*, you might need to override the prerelease status using the pref *toolkit.telemetry.testing.overridePreRelease*. The prerelease and sending status can be checked in *about:telemetry*. If you are *looking at Telemetry data*, there are some changes. In Firefox 58, we will not receive the “extended” data from release anymore. This directly affects some parts of telemetry.mozilla.org that provided release data from that small *“opt-in”* population: - the distribution and evolution dashboards will soon not show release data anymore. - telemetry.js <https://github.com/mozilla/telemetry-dashboard/blob/gh-pages/v2/doc.md> and the aggregates service will not provide release data when 58 is released. If you will be affected by these changes and need alternatives, please reach out to us. Reaching out - If you have any questions reach out to :gfritzsche, :chutten, :dexter, :frank or the team <https://wiki.mozilla.org/Telemetry#Communication>. - For any specific issues, please file a bug <https://bugzilla.mozilla.org/enter_bug.cgi?product=Toolkit&component=Telemetry&blocked=1406390>. We are using bug 1406390 <https://bugzilla.mozilla.org/show_bug.cgi?id=1406390> for tracking. _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
