Allow buffer tabs toolbar positioned vertically.
This is useful when working with laptop computer. Modern laptops often have 9x16 height vs. width ratio. This makes vertical screen space expensive, while there is plenty of space horizontally. So, what I usually do to make things more convenient is getting rid of all bottom toolbars giving entire height of the screen to code window. Other toolbars remain in portrait mode, so no problems here.
Buffer tabs toolbar is very useful, but it cannot be placed in portrait mode. I.e. you can, but tabs inside still positioned horizontally, so placing it in portrait mode doesn't help much. You can remove it too, but it is just too useful.
I guess the right way of fixing this is to make buffer tabs toolbar to identify its mode (portrait or landscape) and place the tabs accordingly.