OK, let's go in order.

Before the dark mode support, setting dark mode in Windows didn't work. So clearly it is not a "simple" issue of applying a system theme, because most applications ignore that windows option.

So my questions are:
- how do you activate dark theme in any app once, and have it work forever? Even if Windows is in light mode. Same for light mode.

Case in point:
void Ctrl::SetSkin(void (*_skin)())

It is not clear what it does and there are 100 more ways to touch skins.