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userChrome.css - Help With Customizing Tabs

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  • Last reply by cor-el

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I made a small CSS customization to my tabs in FF 115 ESR on Windows 7, so they would be flat on the bottom and rounded on the top, looking a bit more like tabs instead of buttons.

Looked ok in FF 115 ESR.

However, in FF 125, half the tabs are now cut off, including their text (see attached images).

Also the tabs background is darker in FF 115 ESR, providing more contrast between the tabs and the tab bar. In FF 125, it's almost all white and I can hardly distinguish between the tabs and the tab bar.

Why is there such a big difference in appearance between FF 115 ESR on Windows 7, and FF 125 on Windows 10?

Here is the code I used...

/* ------------------ RESIZE TAB BAR ----------------------------- */ \#TabsToolbar { height: 27px !important; margin-top: -1px !important; margin-bottom: 0px !important; } \#tabbrowser-tabs { height:25px!important; min-height:25px!important; }

.tab-background-start[selected=true]::after, .tab-background-start[selected=true]::before, .tab-background-start, .tab-background-end, .tab-background-end[selected=true]::after, .tab-background-end[selected=true]::before {

 min-height:25px!important;

} /* ------------------ RESIZE TAB BAR END ----------------------------- */

/* ------------------ TAB HEIGHT ----------------------------- */

.tabbrowser-tab {
 max-height: 25px !important;
 border-color: #8f939e;

}

.tabbrowser-tabs {

 max-height: 25px !important;
 border-color: #8f939e;

} /* ------------------ TAB HEIGHT END ----------------------------- */

I inserted backslashes at the beginning of the first 2 lines of code above to preserve the hashtag sign (otherwise it displays an index number before those lines), please ignore the backslashes.

I would like my customizations in Firefox 125 to look like the ones I made in 115 ESR.

Is it possible?

Thanks!

I made a small CSS customization to my tabs in FF 115 ESR on Windows 7, so they would be flat on the bottom and rounded on the top, looking a bit more like tabs instead of buttons. Looked ok in FF 115 ESR. However, in FF 125, half the tabs are now cut off, including their text (see attached images). Also the tabs background is darker in FF 115 ESR, providing more contrast between the tabs and the tab bar. In FF 125, it's almost all white and I can hardly distinguish between the tabs and the tab bar. Why is there such a big difference in appearance between FF 115 ESR on Windows 7, and FF 125 on Windows 10? Here is the code I used... <code> /* ------------------ RESIZE TAB BAR ----------------------------- */ \#TabsToolbar { height: 27px !important; margin-top: -1px !important; margin-bottom: 0px !important; } \#tabbrowser-tabs { height:25px!important; min-height:25px!important; } .tab-background-start[selected=true]::after, .tab-background-start[selected=true]::before, .tab-background-start, .tab-background-end, .tab-background-end[selected=true]::after, .tab-background-end[selected=true]::before { min-height:25px!important; } /* ------------------ RESIZE TAB BAR END ----------------------------- */ /* ------------------ TAB HEIGHT ----------------------------- */ .tabbrowser-tab { max-height: 25px !important; border-color: #8f939e; } .tabbrowser-tabs { max-height: 25px !important; border-color: #8f939e; } /* ------------------ TAB HEIGHT END ----------------------------- */ </code> I inserted backslashes at the beginning of the first 2 lines of code above to preserve the hashtag sign (otherwise it displays an index number before those lines), please ignore the backslashes. I would like my customizations in Firefox 125 to look like the ones I made in 115 ESR. Is it possible? Thanks!
Attached screenshots

Modified by Slouch

Chosen solution

Note that attribute selectors for the Tab bar that were previously pseudo-boolean attributes like selected and pinned used (i.e. they had a String value like "true") have been converted in 119+ to a real Boolean. You now need to use only the attribute and omit "=true", so use [selected] and :not([selected]) I'm not seeing a selector like .tab-background-start/end in the Firefox source code, so you likely need .tab-background.


For the height of the Tab bar, you merely need to adjust the relevant CSS variable --tab-min-height.

*|*:root {
  --tab-min-height: 25px !important;
  --tab-min-width:  60px !important; /*minimum:50px*/
/*  --tab-overflow-pinned-tabs-width: 175px */
}

Current code for .tab-background that also uses CSS variables :

.tab-background {
  border-radius: var(--tab-border-radius);
  margin-block: var(--tab-block-margin);
  min-height: var(--tab-min-height);
}

See also the CSS selectors defined at the top of this page:

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Chosen Solution

Note that attribute selectors for the Tab bar that were previously pseudo-boolean attributes like selected and pinned used (i.e. they had a String value like "true") have been converted in 119+ to a real Boolean. You now need to use only the attribute and omit "=true", so use [selected] and :not([selected]) I'm not seeing a selector like .tab-background-start/end in the Firefox source code, so you likely need .tab-background.


For the height of the Tab bar, you merely need to adjust the relevant CSS variable --tab-min-height.

*|*:root {
  --tab-min-height: 25px !important;
  --tab-min-width:  60px !important; /*minimum:50px*/
/*  --tab-overflow-pinned-tabs-width: 175px */
}

Current code for .tab-background that also uses CSS variables :

.tab-background {
  border-radius: var(--tab-border-radius);
  margin-block: var(--tab-block-margin);
  min-height: var(--tab-min-height);
}

See also the CSS selectors defined at the top of this page: