/usr/share/icewm/icewm-set-gnomewm is in icewm-common 1.3.8+mod+20161220-1.
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 | #!/bin/sh
echo Previous window manager:
gconftool-2 -g /desktop/gnome/session/required_components/windowmanager
gconftool-2 -s /desktop/gnome/session/required_components/windowmanager --type string icewm
echo New window manager:
gconftool-2 -g /desktop/gnome/session/required_components/windowmanager
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