1975212 - Inconsistent new tab privacy state when opening app that is already running in background vs closed

Status: RESOLVED WORKSFORME

(Firefox for Android :: Homepage, defect, P3)

Description

[Kestrel]

STR:

1. Open Android Nightly 142.0a1.
2. Open a private tab.
3. Close app and swipe it away from recents.
4. Open Nightly from normal app icon (not private shortcut or search widget).
5. Note the privacy state of the new tab.
6. Repeat steps 1-5 but leave app open in background in step 3.

Expected:
New tab is consistently private or non-private regardless of running state of app.

Actual:
When app is running in the background with active private tab, the new tab is created private but when app is not running, the new tab is created non-private.

It is not obvious to the user that the app is already running in the background or not, making the privacy state unpredictable. The running state of an app is an obscure technicality for most users who leave apps running for long periods. Background updates can cause the app to close at any time without the user noticing.

Prior to the regression it would always use the privacy state of the last tab, independent of the app running state, which is more intuitive and consistent from the user's perspective. Consistency is important since the user could expect a private tab but accidentally be using a non-private tab resulting in leaks.

Regression window:
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=87e010ebac62c5bed9a41c64e63df5be347f65e6&tochange=b03555008151d6d19fca7e8986f4c206074e7a82

Regressed by Bug 1968048.

Comment 1

[BugBot [:suhaib / :marco]]

:gl, since you are the author of the regressor, bug 1968048, could you take a look?

For more information, please visit BugBot documentation.

Comment 2

[BugBot [:suhaib / :marco]]

Set release status flags based on info from the regressing bug 1968048

Comment 3

[Kestrel]

Fixed by Bug 1973769.