Hmm. Do you know of a control that does inherit the background from its parent? Usually if you want the same background you have to apply a style with either the same background or just transparent value. The default could be null I guess.
the old tabControl did or maybe it was transparent, the new way maybe correct and I can certainly do what I want with styles. In the past when creating something with say a dialog background I generally only set the background at the top.
@ahopper I will remove the default background for the new TabControl. It makes more sense to have a transparent content area by default. Maybe there is more that doesn't look right so we can work that out in one PR.