Interactive annotation selection and rendering can be unintuitively different sometimes because QPainter won't necessarily stack rendered annotations according to the order of their history. This is more of an issue for image effects like blur and pixelate. The stacking order for painting is determined by QPainter, but the actual contents of the image effect are determined by the history. It is currently possible to visually stack and older blur above a newer blur.

Maybe an explicit Z axis property is needed in the annotation traits system?