Variant #1 seems to be fixed - I cannot reproduce it in rev 69383.

Variant #2 is still reproducible.  After further experimentation, I have
discovered that the incorrect position when closing an undocked window
and then reshowing it only occurs in Y, not in X.  Also, to make it happen
I have to move the undocked window so that the bottom edge is fairly close
to the bottom of the screen.

When I position a window partially off-screen and close it, then reshow it,
the window position is always adjusted so that the window is completely on
screen after the reshow.  I assume this is intentional.  When the bottom
edge of the undocked window is very near the bottom panel (the one with the
Launch buttom) but not overlapping it, closing the window and reshowing it
causes the window to be positioned higher, so that the bottom edge is moved up.
It acts like it doesn't know the true
size of the screen (or the true size of the window) and so is adjusting the window position so that the window is completely visible (but this isn't
necessary because the window is already completely visible before it is closed).

Please try variant #2 with the bottom edge of the undocked window very close to
the bottom edge of the screen.  If you still can't reproduce it, I will take
a look at the video (have to boot Windows to do that).