
As we have removed is_client_decorated from Mutter in the last release. Instead of re-adding it and re-exposing SSD/CSD differences and making gnome-shell deal with that, we created a new API that does exactly what is_client_decorated was used for, so switch to using that. Closes https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/7984 Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/3522>