1713269 - [Experiment] The "Import from previous browser" label is wrongly displayed on the "about:welcome" page's "Import" screen even if the browser attribution code is set to "chrome"

Status: RESOLVED WONTFIX

(Firefox :: Messaging System, defect, P1)

Description

[Marius Coman [:mcoman], Ecosystem QA - PTO until 8th of November, for any requests ping :cmuresan]

Attachment: rec of the issue.gif

[Affected versions]:

• Firefox Beta 89.0 - Build ID: 20210520185752

[Affected Platforms]:

• Windows 10 x64

[Prerequisites]:

• Have the "user.js" from here saved to your PC.
• Have the Chrome browser installed.

[Steps to reproduce]:

1. Open the Chrome browser and navigate to "https://www.mozilla.org/en-US/firefox/channel/desktop/".
2. Download and install the latest Firefox beta.
3. Create a new Firefox profile but do not open it.
4. Go to the previously created profile folder and paste the "user.js" file from the prerequisites.
5. Open the Firefox browser using the recently created profile using the --first-startup argument.
6. Click the "Now now" button.
7. Observe the primary button's label.

[Expected result]:

• The "Import from Google Chrome" label is displayed.

[Actual result]:

• The "Import from previous browser" label is displayed instead.

[Additional Notes]:

• This issue is also reproducible is the Firefox browser was downloaded using the "Edge" browser.
• If the "Import from previous browser" button is clicked the first option from the "Import Wizzard" is selected by default (in our case Microsoft Edge).
• This issue is not reproducible if the profile is not enrolled in the experiment.
• Attached a screen recording of the issue.

Comment 1

[Ed Lee :Mardak]

Looks like we only add ua when it's not an experiment?

https://hg.mozilla.org/releases/mozilla-beta/file/FIREFOX_RELEASE_89_BASE/browser/components/newtab/aboutwelcome/AboutWelcomeChild.jsm#l234

mcoman, if you set messaging-system.log to "all" I would guess it logs "Loading about:welcome with experiment" and not "Loading about:welcome with default data and UA attribution" ?

Comment 2

[Ed Lee :Mardak]

This should be fixed in 90 but wasn't approved for uplift bug 1711700 comment 15.

Comment 3

[Marius Coman [:mcoman], Ecosystem QA - PTO until 8th of November, for any requests ping :cmuresan]

Hi Ed, I can confirm that the "AboutWelcomeChild: Loading about:welcome with experiment: multistage-aboutwelcome-mr1-design" message is displayed in the Browser Console if the messaging-system.log pref is set to all and we navigate to the "about:welcome" page.

Comment 4

[Punam Dahiya [:pdahiya]]

Debugged this is the expected flow for control and treatment branch. In Fx89 , attribution user agent is only set for non-experiment flow as a result in an experiment primary label of import screen always display no attribution label 'Import from previous browser' for control-89 and 'Start Import' for treatment-88

https://searchfox.org/mozilla-release/source/browser/components/newtab/aboutwelcome/AboutWelcomeChild.jsm#235