/usr/bin/fvwm-crystal.play-movies is in fvwm-crystal 3.4.1+dfsg-1.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 | #!/bin/bash
#
# MPlayer wrapper for FVWM-Crystal
USER_ROOT="$(id -un)"
EXEC="/usr/bin/fvwm-crystal.mplayer-wrapper file $USER_ROOT"
CURD="$(pwd)"
for i in *
do
$EXEC "${CURD}"/"${i%%}"
done
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