From Xojo Documentation
Use this property to Get/Set the true bounds of a window (i.e. including frame/title decorations).
On Linux the Left/Top bounds exclude the decorations due to the way window decorations are handled there.
To get the bounds:
To set the bounds, do not modify the Bounds properly directly. This does not work because you will be modifying a temporary object. Instead set the bounds in your own Realbasic.Rect instance and assign that to bounds: