* This lets the user override the default application font.
* Unfortunately Qt seems to behave inconsistently with font scaling from the
system, so we take the font size initially from QApplication::font() (which
doesn't always pick up the font size) and scale from there. While this might
cause some font scaling to be lost it does mean at least we have a consistent
scale, as otherwise you get some text scaling and others not.
* On the light theme we use a less dark background colour improving contrast
with the text.
* On the dark theme the background is still super dark, but we dim the outline
colour which provides an indication of disabled stages
baldurk