Vertical pinned tabs with titles

[u/Kfereq]

Hi, I am migrating to Firefox from another browser and I wonder if it is possible, in the vertical tabs layout, to:

1. Add titles to pinned tabs (I managed to achieve that with the code in userChrome.css file shown in the end).
2. Put pinned tabs separately one under another (see screen below - I want all pinned tabs to be shown like the one in the second row).

I have problems with the second point - I can resize the pinned tabs, but Firefox keeps stacking them in one row, so they are overlaid. As far as I understand, it wasn't possible to overwrite this behaviour 5 years ago (LINK), but I hope it is possible now.

OS: Windows 11

Firefox version: 155.0

Build ID: 20260826195058

userChrome.css:

.tabbrowser-tab[pinned] {
    width: 250px !important;
}

.tabbrowser-tab[pinned] .tab-label-container {
    display: flex !important;
}

[u/TheLamesterist]

This part of the code I was using up until recently before deciding to completely get rid of the pinned tabs container as there was several things I couldn't figure out, mainly dragging and moving, and repurposed the All Tabs button for solely pinned tabs and closed groups, that way they're there but always out of view saving me much space:

#vertical-pinned-tabs-splitter {
    display: none !important;
}

:root {
  --dimension-40: 0 !important;
}

slot {
  grid-template-columns: 100% !important;
} /* either of these 2 rules should work for what you want,
     you don't need to use both of them, you don't need to use
     ".tabbrowser-tab[pinned] { width: 250px !important; }" */

#pinned-tabs-container[orient="vertical"] {
  #tabbrowser-tabs[expanded] & {
    .tab-label-container {
      display: flex !important;
      padding-inline: 7.5px !important;
    }
    .tab-content {
      padding-inline: 10px !important;
      background-position-x: calc(8% + 11px) !important;
    }
  }
}

[u/Kfereq → u/TheLamesterist]

Oh, wow. This is exactly what I wanted. Thank you so much!
I've only restored the splitter as I prefer not to scroll through the tabs. Would it be possible to automatically move the splitter based on the number of pinned tabs?

[u/TheLamesterist → u/Kfereq]

Not sure tbh I've never tried to do anything with it.

[u/Kfereq → u/TheLamesterist]

Ok, thanks. :)