Trying to get a better understanding of masks, I'm using a few basic elements, one of which is an ellipse.
Add layer.
I add a mask to the layer at the top of the stack and put the ellipse on it.
This then masks the underlying objects.
I select the ellipse in the layers panel and move it about the canvas.
It doesn't refresh.
Also, Zoom to Selection works on the other objects but not on the ellipse (mask).
Designer 1.8.0.585
P.S. Am I the only one who would welcome a Masks for Dummies tutorial?