/usr/share/gnome-shell/extensions/ is in gnome-shell-extension-redshift 3.20.1-2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gnome-shell/extensions/redshift@tommie-lie.de/
/usr/share/gnome-shell/extensions/redshift@tommie-lie.de/COPYING
/usr/share/gnome-shell/extensions/redshift@tommie-lie.de/README.md
/usr/share/gnome-shell/extensions/redshift@tommie-lie.de/extension.js
/usr/share/gnome-shell/extensions/redshift@tommie-lie.de/metadata.json
/usr/share/gnome-shell/extensions/redshift@tommie-lie.de/prefs.js
/usr/share/gnome-shell/extensions/redshift@tommie-lie.de/redshift-prefs.ui
/usr/share/gnome-shell/extensions/redshift@tommie-lie.de/schemas/
/usr/share/gnome-shell/extensions/redshift@tommie-lie.de/schemas/gschemas.compiled
/usr/share/gnome-shell/extensions/redshift@tommie-lie.de/util.js