ok, I found the reason for the seeming late kill focus, it isn't related
to the deactivating of the window
(which IMHO wouldn't have to trigger a kill focus, since I might be in a
partial edit, having to look something up in a different app and come back
to finish editing in the same field, only when really leaving the field, a
validation would make sense, but I'll bow to crossplatform behavior here -
so I'll model it after msw if this behaves differently)
the reason for focus kill is the wxFrame::OnActivate when coming back
which sets the focus explicitly, therefore triggering a focus kill... I'll
run the same on msw and compare ...
