/usr/share/kubuntu-default-settings/gtk2-default-theme.rc.sh is in kubuntu-settings-desktop 1:18.04ubuntu11.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 | #!/bin/bash
# Make sure our customised gtkrc file is loaded.
export GTK2_RC_FILES=$HOME/.gtkrc-2.0-kde4
|