/usr/share/xsessions/fvwm-crystal.desktop is in fvwm-crystal 3.2.7+dfsg-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 7 8 9 10 11 12 | # /usr/share/xsessions/fvwm-crystal.desktop
[Desktop Entry]
Encoding=UTF-8
Name=FVWM-Crystal
Comment=Umm... Nice desktop. Transparent, and all...
Exec=fvwm-crystal
Terminal=False
#TryExec=fvwm-crystal
Type=Application
[Window Manager]
SessionManaged=true
|