Is it possible to get the decoration size with libdecor?

Libdecor seems to work with the content size.

I need to set the “whole window” size from the user perspective. So if i set 100x100 it needs to be 100x100 not 100x100 plus decoration.

Does it have a _NET_FRAME_EXTENTS like way to get the sizes? Or a way with the wayland client api / extension?

Thanks.