/usr/ is in xul-ext-calendar-timezones 1.3+build1-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/
/usr/share/xul-ext/
/usr/share/xul-ext/calendar-timezones/
/usr/share/xul-ext/calendar-timezones/chrome/
/usr/share/xul-ext/calendar-timezones/chrome/calendar-timezones-en-US.jar
/usr/share/xul-ext/calendar-timezones/chrome/calendar-timezones.jar
/usr/share/xul-ext/calendar-timezones/chrome.manifest
/usr/share/xul-ext/calendar-timezones/defaults/
/usr/share/xul-ext/calendar-timezones/defaults/preferences/
/usr/share/xul-ext/calendar-timezones/defaults/preferences/preferences.js
/usr/share/xul-ext/calendar-timezones/install.rdf
/usr/share/xul-ext/calendar-timezones/timezones.sqlite
/usr/share/mozilla/
/usr/share/mozilla/extensions/
/usr/share/mozilla/extensions/{92650c4d-4b8e-4d2a-b7eb-24ecf4f6b63a}/
/usr/share/mozilla/extensions/{718e30fb-e89b-41dd-9da7-e25a45638b28}/
/usr/share/mozilla/extensions/{3550f703-e582-4d05-9a08-453d09bdfdc6}/
/usr/share/doc/
/usr/share/doc/xul-ext-calendar-timezones/
/usr/share/doc/xul-ext-calendar-timezones/copyright
/usr/share/doc/xul-ext-calendar-timezones/changelog.Debian.gz
/usr/share/xul-ext/calendar-timezones/defaults/preferences/000system.js
/usr/share/mozilla/extensions/{92650c4d-4b8e-4d2a-b7eb-24ecf4f6b63a}/calendar-timezones@mozilla.org
/usr/share/mozilla/extensions/{718e30fb-e89b-41dd-9da7-e25a45638b28}/calendar-timezones@mozilla.org
/usr/share/mozilla/extensions/{3550f703-e582-4d05-9a08-453d09bdfdc6}/calendar-timezones@mozilla.org