1832278 - [Experiment] [Intermitent] The PDF infobar shows up quite quickly and the Firefox browser doesn’t set itself as default PDF handler while enrolled in Treatment branches of both experiments

Status: VERIFIED FIXED

(Firefox :: Messaging System, defect)

Description

[Simona Rosu [:srosu], Ecosystem QA, PTO until September 8 - NI to: [e-mail]]

Attachment: PDFInfobar_ShowsTooSoon.gif

[Affected versions]:

• Firefox Release 113.0 (Build ID: 20230504192738)

[Affected Platforms]:

• Windows 10 x64

[Prerequisites]:

• Have the Firefox Beta 113.0 build installed and opened.
• Have the Firefox Browser set as default.
• Have saved the user.js and times.json files on your computer.
• Have the “browser.newtabpage.activity-stream.asrouter.devtoolsEnabled” pref set to true in the “about:config” page.

[Steps to reproduce]:

1. Navigate to the “about:support” page and open the Profile Folder.
2. Paste the user.js and times.json files from prerequisites and restart the browser.
3. Navigate to the about:studies page and make sure that the profile is enrolled in both “Existing Users - Set default Pdf handler” and “Existing Users - Set default Pdf handler Message” experiments.
4. Open a new tab and make sure that the PDF infobar is displayed. If not, restart the browser.
5. Click the "Expand devtools" icon from the top-right corner of the NewTab, and on Targeting section search for "isDefaultHandler" attribute.
6. Observe its value.
7. Verify the default OS PDF handler via Start → Default Apps → Choose default apps by filetype.

[Expected result]:

• Step 6: The value of the "isDefaultHandler" attribute is: { "html": true, "pdf": true }
• Step 7: The Firefox browser is set as default PDF handler.

[Actual result]:

• Step 6: The value of the "isDefaultHandler" attribute is: { "html": true, "pdf": false}
• Step 7: The Firefox browser is not set as default PDF handler.

[Notes]:

• I managed to reproduce this issue on 8 out of 10 profiles.
• Attached is a screen recording of the issue.

Comment 1

[Jason Prickett]

This shares a root cause with Bug 1832283, and should also be fixed from the recipe update. It is also expected that some of the population will be in the treatment branch for both experiments, and therefore will not have Firefox set as their default PDF handler by the initial experiment.

Comment 2

[Simona Rosu [:srosu], Ecosystem QA, PTO until September 8 - NI to: [e-mail]]

I‘ve verified this issue using Firefox Release 112.0.2 (Build ID: 20230424110519) and Firefox Release 113.0 (Build ID: 20230504192738) on Windows 10 x64.

• The infobar appears only after the Firefox browser is set as default PDF handler.

Considering this, and based on comment 1, I'm closing this issue as Fixed and marking it as Verified.