bug#28620: Interact directly on Emacs bug#28620: mouse drag event records wrong release window

[martin rudalics]

> ​Ok.  It would be more helpful if you explained which problems you feel are
> relevant to the discussion at hand.

For example that of getting the screen dimensions of a window.  Have a
look at x_real_pos_and_offsets to get an idea of the tribulations needed
to do that for an Emacs frame.  These are by far the most complicated
operations we do in the X specific code and I have reports that we still
do not get the right results everywhere.

martin