Setting for Classic Tabs (frameless?)

[Chaosbender]

After updating FF to Nightly 130.0a1, I would like to get the classic tabs back. Now every tab is a (large) button with a frame, which distracts me. The normal FF has borderless tabs (only the active tab has a frame).

Sadly only Nightly without an activated theme is now borderless, every theme creates those borders (even older ones).

Is there a setting (maybe in the about:config) to keep the borderless tabs?

[Agentvirtuel]

Hello

For information purposes
If you'd like to try https://www.userchrome.org

https://connect.mozilla.org/t5/discussions/improvements-to-the-firefox-sidebar-are-on-the-way/m-p/61...
https://forums.mozillazine.org/viewtopic.php?t=3123082

Other https://www.reddit.com/r/FirefoxCSS

[Lakay]

I agree, new borders are very distracting.  I am using "Dark Reader" theme. easier on the eyes.
New Borders are white (ffffff), and as I said, very distracting.
There was a suggestion to go to Chrome.  I rather like Nightly and would prefer not to go to Chrome.

My vote, create an option to "Remove Tab Borders".

Thanks Folks.

[jscher2000]

Could this be related to a "high contrast" setting? If not, I guess you could contact your favorite theme authors and ask them whether they can work around it with an update.

[Lakay]

The lines around the tabs just appeared in the new Nightly release 130.0a1.

I did try adjusting the contrast.  No change.

Edit: I am not using any theme.  Nightly's default.

[jscher2000]

I think I found the relevant bug:

1881851 - Toolbarbuttons should have a visible border in prefers-contrast/forced-colors 

This isn't actually a change for users whose Firefox detects a preference for increased contrast, it affects people who have forced-colors.

Why would someone have forced-colors? Is that based on an OS setting? It would be useful to gather information on who is affected.

By the way, there is a preference related to forced colors (layout.css.forced-colors.enabled), but according to one bug, it doesn't affect the toolbar area (1705168 - Enable forced-colors in UA+Chrome regardless of pref ).

----

So why don't the outlines appear on the built-in dark theme? That theme sets a CSS variable which makes the outline transparent:

/* Firefox code for background tabs in themes */
outline: var(--tab-outline);
--tab-outline: 1px solid var(--tab-outline-color);
--tab-outline-color: transparent;
@media (forced-colors) {
--tab-outline-color: ButtonText;
}
&[lwtheme] {
--tab-outline-color: var(--lwt-tab-line-color, currentColor);
}

/* Style rule for built-in dark theme (alpha channel set to 0 makes it transparent) */
--lwt-tab-line-color: rgba(0, 0, 0, 0);

The dark theme manifest (/browser/themes/addons/dark/manifest.json line 29) has this property under the "colors" key:

"tab_line": "transparent",

so I think that is how theme authors can avoid background tab borders, too.

[Lakay]

Just to say it again, I am using the nightly default theme.

In Nightly Settings / Language and Appearance, I have appearance set to dark.

Not all websites follow that, such as Round Cube on my hosting server.  Considering the time I spend responding to emails during the day, I would like my email interface to be dark.  I installed "Dark Reader", which forces all web pages to Dark Mode.

Yes. Dark Reader does put the thick white border around the tabs.  Disabling Dark Reader removes those white lines.

Interesting, Dark Reader has not updated recently.  It was specifically Nightly's upgrade to 130.0a1 that introduced the white borders.

I should email the Dark Reader folks, see what they think.

[Lakay]

Follow up:

I use the Nightly default Browser theme, set to "Dark Theme"

As I mentioned not all web pages follow that.

Therefore I added "Dark Reader" to force all web pages to "Dark".  As a result of Nightly's upgrade to 130.0a1, there were thick white lines around each tab.

Opening up Dark Reader "Settings" and unchecking "Change Browser Theme" did remove the white lines around the tabs.

Some features did also cease to function, although Dark Reader did continue to force all web pages to Dark.  "Contrast" etc. did continue to function.  I am able to customize through Dark Reader well enough that I am happy with how Nightly appears.

Back to business.

[jscher2000]

This will be reverted in Firefox 130. The patch was just checked in: https://bugzilla.mozilla.org/show_bug.cgi?id=1907103