Jonas Ådahl authored Mar 15, 2019 and Florian Müllner committed Mar 17, 2019

When a parent window is moved, attached windows (attached modal dialogs
or popups) is moved with it. This is problematic when such a window
hasn't been shown yet (e.g. a popup that has been configured but not
shown), as it'll mean we try to constrain an empty window. Avoid this
issue by not trying to auto-move empty windows.

!496