
The current preference API - buildPrefsWidget() - predates client-side decorations. While extension authors have been finding ways around the limitation of not having access to the window/titlebar, the change to the new Adwaita API seems like a good time for an updated API that officially provides that access (as far as allowed by libadwaita). Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2012>