1974207 - Sidebar special tabs do not switch background color when changing light/dark themes or viceversa

Status: RESOLVED WONTFIX

(Toolkit :: Themes, defect)

Description

[Daniel Bodea [:danibodea]]

Note

• Background color of Sidebar special tabs does not switch when changing themes, when specific themes are installed. This happens when having Chatbot AI opened and switching from a light theme to a dark theme. The background only changes after going through the other tabs (Tabs from other devices, History, Bookmarks).

Found in

• Release v140.0.1

Affected versions

• Release v140.0.1
• Release v140.0

Unaffected versions

• Beta v141.0b2
• Nightly v142.0a1

Tested platforms

• Affected platforms: Windows 10, Ubuntu 22, MacOS 15
• Unaffected platforms: none

Steps to reproduce

1. Enable Sidebar
2. Install the following themes:
   a. https://addons.mozilla.org/en-US/firefox/addon/colorful-abstract-neon/
   b. https://addons.mozilla.org/en-US/firefox/addon/visionary-balanced/?utm_source=addons.mozilla.org&utm_medium=referral&utm_content=search
   c. https://addons.mozilla.org/en-US/firefox/addon/activist-balanced_/
3. Open the AI chatbot screen from the Sidebar.
4. Load about:addons
5. Switch from a dark theme to a light one or vice-versa

Expected result

• The AI Chatbot screen background color switches from dark to light or vice-versa, as intended.

Actual result

• The AI Chatbot screen background color does not switch from dark to light or vice-versa.
• The Tab background does not switch when focusing Tabs from other devices, History, but it will switch to the correct background color when switching to Bookmarks tab.

Regression range

• It does not occur in the later versions: Beta v141.0b2, Nightly v142.0a1.

Additional notes

• The issue only reproduces if the mentioned themes are installed.
• The issue reproduces with both Horizontal or Vertical Tabs enabled.
• The issue reproduces when switching between the main Dark and Light Themes (if the mentioned themes are installed).
• The issue seems related to bug 1971487.
• Demo: https://drive.google.com/file/d/1rrekLJgyhk23uu9XEhrs7Fo_4jp0dxXH/view?usp=sharing

Comment 1

[Daniel Bodea [:danibodea]]

I managed to reproduce the issue even without any new themes installed:

Revisioned steps to reproduce are:

1. Open Sidebar
2. Open Bookmarks from Sidebar
3. Load about:addons and enable Dark Theme
4. Open AI chatbot from Sidebar
5. Load about:addons and enable Light Theme
   Observe: The AI chatbot screen background remained dark when it should have switched to light.

After that, if the user now switches to Tabs from other devices and History, they have a correct background, but AI chatbot remains in the light theme background. The AI chatbot background only switches after the user focuses the Bookmarks tab and then focuses AI chatbot again.

Please note that installing one or more of the themes mentioned above influences how this issue reproduces, making it worse.

Comment 2

[Daniel Bodea [:danibodea]]

I've managed to find the regressor: Practically, it started reproducing when the Bookmarks button was added to the Sidebar. The regressor that I managed to find is bug 1947997.

Mozregression results:
Bug 1947997 - Make sidebar.main.tools user customized r=sidebar-reviewers,firefox-desktop-core-reviewers ,mossop

• Update sidebar.main.tools default values and include a migration
• Modify updateDefaultTools in SidebarManager
• Update tests
  Differential Revision: https://phabricator.services.mozilla.com/D240903

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

:sclements, since you are the author of the regressor, bug 1947997, could you take a look? Also, could you set the severity field?

For more information, please visit BugBot documentation.

Comment 4

[Daniel Bodea [:danibodea]]

The issue stopped reproducing after the fix in bug 1968040.

Mozregression results:
Bug 1968040 - Set color-scheme on root based on lwtheme-brighttext. r=emilio,desktop-theme-reviewers
Differential Revision: https://phabricator.services.mozilla.com/D250791

Kindly note that a new issue has emerged following this change: while the background updates correctly upon switching to the AI Chatbot screen, the content appears faded or washed out. This issue has also been fixed and does not occur in Beta v141.0b1 or latest Nightly v142.0a1.

Comment 5

[Donal Meehan [:dmeehan]]

Resolving this as WONTFIX, discussed in an internal Slack thread.
Bug 1968040 is riding the train with Fx141/Fx142, but it was already backed out of release for Fx140.
We won't take a different patch for Fx140 release for this.