I can't see a method for this.

I have a shape that I have created with a shadow, a Novelty line, or even a blend, bevel, contour or envelope.
If I place it on top of a larger box and Combine Shape > Slice Shapes, I lose the decorative edging.
Using the 3D Tool loses the edging.
I've tried creating a bitmap copy but on slicing you get a rectangular cut out.

I would be grateful for any pointers?

Acorn