[Lazarus] clDefault for TCustomControl

[cobines]

Hello.

I have a TCustomControl for which I have set:

ParentColor := False;
Color := clDefault;

On Linux/LCLGtk2 and Windows/LCLWin32 this results in clWindow color,
but on Linux/LCLQt it is different, looks like clForm or clBackground.
When I'm assigning Color:=clDefault I see that
TControl.GetDefaultColor is called and the return value is clWindow.
Shouldn't this mean that clDefault will always mean clWindow for this
control? Is it normal that the widgetset may overwrite clDefault
value?

--
cobines