/usr/share/doc/cpl-plugin-xsh-doc/html/_static/doctools.js is in cpl-plugin-xsh-doc 2.3.0+dfsg-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/cpl-plugin-xsh-doc/html/_static/../../../../javascript/sphinxdoc/1.0/doctools.js