postrm is in kinput2-common 3.1-12.
This file is a maintainer script. It is executed when installing (*inst) or removing (*rm) the package.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 | #!/bin/sh -e
XRESOURCE=/etc/X11/Xresources/kinput2-common
if [ "$1" = "purge" ]; then
rm -f $XRESOURCE
fi
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