2012255 - Private Browsing mask badge on tab-tray-button is hard to see with light theme

Status: RESOLVED DUPLICATE of bug 2011413

(Firefox for Android :: Toolbar, defect)

Description

[Daniel Holbert [:dholbert]]

Steps to reproduce

1. Ensure that your device is using a "light" theme in System Settings; and in Firefox Nightly's Settings|Customize section, choose to follow the device theme.
2. On the Firefox Home Page, tap the mask icon at the top-right corner, to go to Private Browsing Mode.
3. Look at the tab-tray button (which says [0] or however many private browsing tabs you have open)

Expected behavior

The private-browsing badge (on the tab-tray button) should have a white mask in it (to be visible against the dark-purple surroundings)

Actual behavior

The private-browsing badge (on the tab-tray button) has a black mask in it, which is hard to see against the dark-purple surroundings.

Device information

• Firefox version: 149.0a1 2026-01-22 (also affects 147 release and 148 beta)
• Android device model: Pixel 10 Pro XL, Pixel 6a
• Android OS version: 16

Any additional information?

If you repeat the STR with a dark theme, you get EXPECTED RESULTS. Private Browsing UI looks essentially the same regardless of light/dark theme; but this is one spot where we're mistakenly using a theme-specific color, and the theme-specific color ends up being hard to see in a light theme.

Comment 1

[Daniel Holbert [:dholbert]]

Attachment: screenshot of bug (taken after enabling "light" theme in Android settings)

Comment 2

[Daniel Holbert [:dholbert]]

Attachment: screenshot of expected rendering (taken after enabling "dark" theme in Android settings)

Comment 3

[Daniel Holbert [:dholbert]]

Attachment: screenshot showing the unexpectedly-black-mask

In case it's not obvious at first, here's a screenshot focusing in on the "bad" part from the "screenshot of bug" attachment.

This is literally the only difference between my two screenshots -- the mask color is white (easier to see) if you have a dark OS theme enabled, vs. black (harder to see) when you have a light OS theme enabled.

Comment 4

[Daniel Holbert [:dholbert]]

Looks like this regressed about a month ago.

Regression range info from mozregression:
INFO: Newest known good nightly: 2025-12-10
INFO: Oldest known bad nightly: 2025-12-11

https://hg-edge.mozilla.org/mozilla-central/pushloghtml?fromchange=193270a369a8a26ae3dc8689656cc09748f37811&tochange=c199d0410aaf9a8614c4bf632f0501f65c2dc985

Not sure what in there might've regressed this -- maybe bug 2004703?

Comment 5

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

Set release status flags based on info from the regressing bug 2004703

:gl, since you are the author of the regressor, bug 2004703, could you take a look?

For more information, please visit BugBot documentation.

Comment 6

[Daniel Holbert [:dholbert]]

(In reply to Daniel Holbert [:dholbert] from comment #4)

Not sure what in there might've regressed this -- maybe bug 2004703?

(Yeah, looks like that's the regressor. This seems like a variant of the other regressions that are hanging off of that bug -- bug 2005941 and bug 2005961)

Comment 7

[Moyin [:moyin]]

Thank you Daniel for reporting this bug and for providing the screenshots. Nicole from UX already reported this bug a couple of days ago and it has already been added to our backlog, so I'll mark this ticket as duplicate.