/usr/share/xul-ext/ is in xul-ext-pwdhash 1.7-13.
This file is owned by root:root, with mode 0o755.
..
/usr/share/xul-ext/pwdhash/
/usr/share/xul-ext/pwdhash/chrome/
/usr/share/xul-ext/pwdhash/chrome.manifest
/usr/share/xul-ext/pwdhash/chrome/content/
/usr/share/xul-ext/pwdhash/chrome/content/contents.rdf
/usr/share/xul-ext/pwdhash/chrome/content/domain-extractor.js
/usr/share/xul-ext/pwdhash/chrome/content/hashed-password.js
/usr/share/xul-ext/pwdhash/chrome/content/md5.js
/usr/share/xul-ext/pwdhash/chrome/content/stanford-pwdhash-overlay.css
/usr/share/xul-ext/pwdhash/chrome/content/stanford-pwdhash-overlay.xul
/usr/share/xul-ext/pwdhash/chrome/content/stanford-pwdhash-page.css
/usr/share/xul-ext/pwdhash/chrome/content/stanford-pwdhash-page.xml
/usr/share/xul-ext/pwdhash/chrome/content/stanford-pwdhash.js
/usr/share/xul-ext/pwdhash/chrome/locale/
/usr/share/xul-ext/pwdhash/chrome/locale/en-US/
/usr/share/xul-ext/pwdhash/chrome/locale/en-US/contents.rdf
/usr/share/xul-ext/pwdhash/chrome/locale/en-US/stanford-pwdhash.properties
/usr/share/xul-ext/pwdhash/install.js
/usr/share/xul-ext/pwdhash/install.rdf