Color previous tab when using Tabs Outliner window as a tab instead of window

Situation: I _never_ use Tabs Outliner in a separate window. I always move it as the first tab in the existing window.

Effect/consequence:

However, a logical side effect of that is that the color option for the "active tab" looses its meaning, as it always will be showing that color only for the Tabs Outliner tab, as it is that one which is the active tab each time we are looknig at the Tabs Outliner view...

Solution:

Therefore I suggest that Tabs Outliner builds in a detection that simply colors the previous tab as the "active tab" when detecting that Tabs Outliner runs as a tab instead of in its own window.