/usr/share/xsessions/herbstluftwm.desktop is in herbstluftwm 0.6.2-1.
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]
Encoding=UTF-8
Name=herbstluftwm
Comment=Manual tiling window manager
Exec=herbstluftwm
Type=XSession
|