/usr/share/xgreeters/lightdm-kde-greeter.desktop is in lightdm-kde-greeter 0.3.2.2-1ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | [Desktop Entry]
Name=LightDM KDE Greeter
Comment=This runs the KDE greeter, it should only be run from LightDM
Exec=lightdm-kde-greeter
Type=Application
X-Ubuntu-Gettext-Domain=lightdm
|