Remove the titlebar, for more space…

[bwinton]

It should look something like this on macOS:

(Added #verticaltabs-box { padding-top: 32px; } in the Inspector.)

and something like this on Windows:

(Added #nav-bar { margin-right: 138px; } in the Inspector.)

But if @phlsa or @shorlander disagree, go with their suggestions instead… 😉

[ChrisW-B]

I've been maintaining a version similar to this in my spare time, if that helps. While the Windows version is exactly the same, I elected to shift the tab center down instead when not in fullscreen for OS X

its here if you want to look at it ChrisW-B/TabCenter

[bwinton]

Yeah, @phlsa has been adamantly against putting the urlbar above the tabs (for similar reasons to us having the tabs above the urlbar in the regular layout), so we're probably not going to go in that direction… But thanks for the pointer! 🙂

[ChrisW-B]

I made a quick version of it by adding

#main-window:not([inFullscreen]):not([inDOMFullscreen]) #verticaltabs-box {
  padding-top:25px!important;
}

to OSX.css

But I think the main problem you'd have is what to do with the collapsed version

If you were to go through removing the titlebar, I'd guess that you'd have to either extend the navigator toolbox backwards, make the collapsed section larger, or have some short of tetris/upside down L shaped section

[JonasCz]

Using it with Hide Caption Titlebar Plus on Linux works quite well, too: