To move and resize a custom control on a Canvas in run-time in a WPF project, I'm using the code here: http://csharphelper.com/blog/2017/05/move-resize-multiple-rectangles-wpf-c/ and here: How to drag a UserControl inside a Canvas
However, the control doesn't move smoothly, it's jerky and jittery - kind of like in the days before WPF when we would turn on double-buffering (which I understand is unnecessary in WPF). Any ideas how to make the move/resize smooth?