TL;DR
Include Cliffs into the Deconstructor Function Trees /stone only (d.k. the English version of this)What?
Include Cliffs into the constructor function stone trees onlyor make another checkbox for the cliffs.
Why ?
When you use the Function Stone/trees only you want to get rid of stuff that prevents you from building or walking.In this case, Cliffs are the same as trees or stone. When I want to clear a big area of Build-preventing stuff I can Filter the D.Planer manually for every tree, every stone, and cliffs, or I can do it in 2 passes. 1st trees and stone, second cliffs. Combining them would make the deconstruction Life easier.
EDIT: Or: allow us to add filter while the Trees/stone checkbox is checked and our filter just goes on top of it.