/usr/share/GConf/gsettings/gnome-bluetooth-nst is in gnome-bluetooth 3.2.2-0ubuntu5.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | [org.gnome.Bluetooth.nst]
last-used = /desktop/gnome/nautilus-sendto/last_obex_device
|