/etc/xdg/kservice.categories is in libkf5service-data 5.44.0-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | kf5.kservice.services service (kservice lib)
kf5.kservice.sycoca sycoca (kservice)
|