I don't know about you, but I usually walk into a room where there are other people first. If they're people who don't know me, I introduce myself.
but I admit that of these times it is increasingly rare to hear and see people who behave in the same way... .
However, formality aside, I think it is not possible to do what you ask
Attached I send you an alternative solution.... in practice are not two overlapping windows, but one is a normal window (blue) and the other is a polygonal (red) window carved by repassing the window below and then deleting the original. . .
cmq a little formality sometimes does not spoil.. .