/usr/share/ubufox/defaults/preferences/001ubuntukylin-browser-defaults.js is in ubuntukylin-default-settings 1.3.14.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/ubufox/defaults/preferences/../../../ubuntukylin-default-settings/ubuntukylin-browser-defaults.js