Add Scrollbar.Value
Fixed Rect.Contract by margin
Move some UI structs to System so they can be used by Tools
Move viewport to QAbstractScrollArea
Add Scrollbar.PageStep, SingleStep
Add BaseScrollWidget.OnScrollChangedf
Add MarginProperty
Connect SliderMoved
Explicitly mark out of memory errors
Prevent frameless window stuff messing with popups/tooltips
Widget.OnDoubleClick calls OnMousePress by default
Drag.Execute returns a DropAction
Add Drag.SetImage
Add smooth scrolling to BaseScrollWidget
Create ScrollExperiment.cs
Compatibility fix