The gdefaults2 file is usually located inside the .crossfire directory.
This file applies to the new gtk-2 client for crossfire,
The older gtk-1 client used the gdefaults file as configuration file.

At the top of the file one reads :

# crossfire-client-gtk2 automatically generates this file.
# Manual editing is allowed, but the client may be a bit
# finicky about the keys and values.  Comparisons are case
# sensitive.  'True' and 'False' are the proper case, but
# have been replaced with 1 and 0 respectively.

Where the part 'True' and 'False' are the proper case
once applied to the X11 cfclient configuration file defaults .

See the gdefaults configfile, since the gdefaults2 does not differ much.