1746000 - Border of the active tab is displayed differently between default theme and custom theme

Status: RESOLVED WONTFIX

(Firefox :: Theme, defect)

Description

[Tooru Fujisawa [:arai]]

Attachment: border of active tab, with/without custom theme

Steps to reproduce:

1. run Nightly 97.0a1 (2021-12-14) (64-bit) on macOS, with clean profile
2. go to https://addons.mozilla.org/en-US/firefox/addon/a-n-i-m-a-t-e-d-kitty-cat/
3. click "Install Theme" and "Add"

Actual result:
active tab's has black border, that doesn't match the remaining of the UI, nor the default theme's where it has gray border

Expected result:
active tab has gray border, or any color of border that matches the remaining of the UI

Regression range:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=ac52da65f48fb66f9df0c93a33fb57ba3bb68465&tochange=965bf155a9db49ce7ec1533b3b8eee2901a79d4e

Comment 1

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

Set release status flags based on info from the regressing bug 1740788

Comment 2

[Dão Gottwald [:dao]]

This is intentional change. We previously ignored the tab_line property and hardcoded the border color. tab_line is now supported for all themes, using the text color as a fallback.

Comment 4

[Dão Gottwald [:dao]]

I suppose falling back to toolbar_top_separator first might be better.

Comment 5

[Kazumasa Hasegawa (Kazz)]

tab_line is optional.
I think it's better using transparent instead of text color (currentColor) as a fallback.

Comment 6

[Sören Hentzschel]

Firefox 96 was released yesterday and since then we get many support requests due to the strong border of the active tab. Is the expectation that every (affected) theme has to release an update or are you planning a change soon? I would like to know what should be communicated in the Firefox support. Thanks.

Comment 7

[Igor Mackeev]

This "strong border" is something absolutely unacceptable. Is there a way to remove it with css code in userChrome? I'm using a black theme and after the update to 96 I'm seeing the ugliest and the most annoying WHITE border around active tab! Rolled back to 95 for the time being.

Comment 8

[Sören Hentzschel]

Igor, for security reasons your should NEVER run outdated browsers. Please see https://www.mozilla.org/en-US/security/advisories/mfsa2022-01/ for security issues that got fixed in Firefox 96. Yes, in the meantime you could change the style via userChrome.css but Bugzilla is not the right place to discuss individual customizations. You could create a thread on https://www.reddit.com/r/FirefoxCSS/, for example.

Comment 9

[Igor Mackeev]

Thank you for your concern. I prioritize mental health over FF security. I figured out how to get rid of the "strong border." It took me a couple of hours, which I could've spent doing something more productive. Such uncalled-for changes are good for nothing but generating outrage and frustration. My apologies for nonsensical complaints in this bug report. This was outrage and frustration talking.

Comment 10

[Dão Gottwald [:dao]]

Aaron, do you have thoughts on this? We added a border around the selected tab for third-party themes in Firefox 96, using the text color as the default color. It helps make the selected tab more visible, a common complaint with Proton. It's in line with the "Bold" colorway variants we've shipped, and I think it makes sense to update our webextension theme implementation as our design language evolves. That said, this is a pretty significant change that some users and theme authors won't appreciate, although authors can update their themes to set a transparent or otherwise custom border color.

Comment 12

[CoolCmd]

Attachment: Custom theme with currentColor and transparent borders

(In reply to Dão Gottwald [::dao] from comment #10)

We added a border around the selected tab for third-party themes in Firefox 96, using the text color as the default color. It helps make the selected tab more visible, a common complaint with Proton.

The default color is chosen poorly. Maybe the text color is good for a high contrast theme, but not for a normal one. Use transparent or something else.

although authors can update their themes to set a transparent or otherwise custom border color.

It is just unrealistic.

---

Workaround for userChrome.css:

:root {
    --lwt-tab-line-color: transparent;
}

See attached screenshot.
Theme: https://addons.mozilla.org/en-US/firefox/addon/apple-look-stainless-steel/
Top window use currentColor, bottom window use transparent.

Comment 13

[Sören Hentzschel]

although authors can update their themes

It is just unrealistic.

At least such drastic changes about the appearance of themes should be communicated on blog.mozilla.org/addons and maybe other channels a few weeks before such changes land in a stable release of Firefox so that theme authors have a chance to do the necessary changes. I think the bigger problem as the change itself (you can never make everyone happy) is that it was a surprise. Of course it's not realistic that every theme author will update their theme (and maybe some theme authors even think that it's a good change for their theme). But it's really important that at least extension developers and theme authors can react before their users are affected by a "breaking" product change. And I would argue that such a visible change of a theme is kind of a "breaking change" from the point of view of a theme developer. And it would also have been helpful for the support community to know about this before we got surprised by the affected users.

So regardless of whether there will be another product change or not - maybe you could include the topic communication in your post mortem about Firefox 96 to prevent similar situations in the future. Thank you!

Comment 14

[Dão Gottwald [:dao]]

It looks like we're not going to change course here, although we might tweak the default border color as part of bug 1746000.