/usr/share/mozilla/extensions/{aa3c5121-dab2-40e2-81ca-7ea25febc110}/jid0-9XfBwUWnvPx4wWsfBWMCm4Jj69E@jetpack is in xul-ext-self-destructing-cookies 0.4.12-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/mozilla/extensions/{aa3c5121-dab2-40e2-81ca-7ea25febc110}/../../../xul-ext/self-destructing-cookies