Clear outside shape

Clear reverse. If you draw lets say a circle on another shape, instead of clearing the circle, clear all the rest in that (overlapping) group.

I use shapes to make different backgrounds. I want to use a blurred background except in my shape.

You can use the multiply filter to make this.

Create a white circle, over this in the Overlap group put your image background, in the paint of this image set the Filter to Multiply, you are going to have the circle with the image of your background.

Tnx for the great tip