1986654 - A "Dark" or "Light" theme card is added to the about:editprofile page when a user creates a profile with the "Gray" theme and the OS theme is switched between Dark and Light

Status: NEW

(Toolkit :: Startup and Profile System, defect, P3)

Description

[Raluca Popovici, Desktop QA]

Attachment: Screencast From 2025-09-03 15-03-17.webm

Found in:
Nightly 144.0a1(2025-09-02)

Affected versions:
Nightly 144.0a1(2025-09-02)

Tested platforms:
Affected platforms: macOS 13.2.1, Windows 11, Ubuntu 24.10

Preconditions:
Ensure that the pref "browser.profiles.enabled" is set to true in about:config.

Steps to reproduce:

1. Set the OS theme to "Dark" and create Profile 1 using the "Gray" theme and observe the themes card available
2. Set the OS theme to Light and go back to the profile created at step 1.
3. Go to the about:editprofile page for the selected profile and observe the themes card available.

Expected result:
No "Dark"/"Light" theme added to the themes list, and the background color of the browser is updated to "Gray"
theme on Light OS theme.

Actual result:
A "Dark" theme card is added to the themes list, and a "dark" background color of the browser is displayed.

Regression range:
It's not a regression.

Additional Notes:
I only noticed this issue after creating a profile using the "Gray" theme, then switching the OS theme from Dark to Light. If you switch back to the "Dark" OS theme, then the "Dark" theme card is not displayed anymore in about:editprofile page.

Comment 1

[Raluca Popovici, Desktop QA]

Attachment: Screencast From 2025-09-03 14-58-14.webm