1720677 - All the preferences set and created with experiment values before enrollment are reset/deleted at unenrollment (2 restarts after enrolling)

Status: NEW

(Firefox :: Normandy Client, defect)

Description

[Maria Heres, inactive, contact Ecosystem QA]

Attachment: multipref default all.gif

[Affected Versions]:

• Firefox 90.0 (Build ID: 20210705185941)
• Firefox Beta 91.0b2 (Build ID: 20210713163746)
• Firefox Nightly 92.0a1 (Build ID: 20210714215010)

[Affected Platforms]:

• Windows 10
• Linux Mint 20
• macOS 11.1

[Prerequisites]:

• Have a Normandy default type recipe for an experiment that will create some preferences with values not default to Firefox and set some new tab preferences to non-default values.
  E.g. default type recipe for:
  “browser.topsites.experiment.ebay-2020-1” to “true”
  “browser.newtabpage.activity-stream.section.highlights.rows” to “2”
  “browser.display.focus_background_color” to “....”.
• Have a user.js file that will enroll you in the experiment.
• Have Firefox open (not enrolled in study).

[Steps to reproduce]:

1. Navigate to “about:config”
2. Create preferences with the experiment values (i.e. “browser.topsites.experiment.ebay-2020-1” to “true”)
3. Set preferences with experiment values (i.e. “browser.newtabpage.activity-stream.section.highlights.rows” to “2” and “ “browser.display.focus_background_color” to “....”)
4. Restart the browser.
5. Open the “Profile Directory” folder and copy the user.js file from prerequisites there.
6. Restart Firefox thrice (1 to enroll, 2 after).
7. Navigate to “about:studies” and unenroll from the study.
8. Restart Firefox.
9. Go to "about:config" and observe the preferences.

[Expected result]:

• Preferences set before enrolling are kept on user value after unenrollment.

[Actual result]:

• All references set before enrolling are reset/deleted after unenrollment if they have the same value as the one used by that branch.

[Notes]:

• Attached is a recording of the issue.