/usr/share/games/xboard/themes/conf/sho.fen is in xboard 4.8.0-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1
lnsgkgsnl/1r2e2b1/ppppppppp/9/9/9/PPPPPPPPP/1B2E2R1/LNSGKGSNL w 0 1