The Quick Terminal would not appear anymore, as somewhere
in the framework the Quick Terminal Window's geometry
gets corrupted when the window is added to the UI.
This works around by caching the windows geometry and
reusing it afterwards
Fixes#4999
We need to set the level to popUpMenu so that we can move the window
offscreen and animate it over the main menu, but we must reset it back
to floating after the animation is complete so that other higher-level
windows can be shown on top of it such as IME windows.
Tobias Pape