/usr/share/horde/js/ckeditor/config.js is in php-horde-editor 2.0.4+debian0-3build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/horde/js/ckeditor/../../../javascript/ckeditor/config.js
/usr/share/horde/js/ckeditor/../../../javascript/ckeditor/config.js