/usr/share/xml/docbook/custom/ is in docbook-website 2.5.0.0-8.
This file is owned by root:root, with mode 0o755.
..
/usr/share/xml/docbook/custom/website/
/usr/share/xml/docbook/custom/website/1.10
/usr/share/xml/docbook/custom/website/2
/usr/share/xml/docbook/custom/website/2.0b1
/usr/share/xml/docbook/custom/website/2.2
/usr/share/xml/docbook/custom/website/2.4.0
/usr/share/xml/docbook/custom/website/2.5.0/
/usr/share/xml/docbook/custom/website/2.5.0/VERSION
/usr/share/xml/docbook/custom/website/2.5.0/catalog.xml
/usr/share/xml/docbook/custom/website/2.5.0/css/
/usr/share/xml/docbook/custom/website/2.5.0/css/dynxbel.js
/usr/share/xml/docbook/custom/website/2.5.0/css/example.css
/usr/share/xml/docbook/custom/website/2.5.0/extensions/
/usr/share/xml/docbook/custom/website/2.5.0/extensions/saxon64.jar
/usr/share/xml/docbook/custom/website/2.5.0/extensions/xalan2.jar
/usr/share/xml/docbook/custom/website/2.5.0/schema/
/usr/share/xml/docbook/custom/website/2.5.0/schema/ChangeLog
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/ChangeLog
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/autolayout.dtd
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/catalog
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/extensions.mod
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/forms.mod
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/layout.dtd
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/namespaces.mod
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/rddl.mod
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/website-custom.dtd
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/website-full.dtd
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/website.dtd
/usr/share/xml/docbook/custom/website/2.5.0/schema/dtd/website.mod
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/ChangeLog
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/autolayout.rng
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/config.xml
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/extensions.rng
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/forms.rng
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/layout.rng
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/rddl.rng
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/union.xml
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/website-full.rng
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/website.rng
/usr/share/xml/docbook/custom/website/2.5.0/schema/relaxng/websitedb.rng
/usr/share/xml/docbook/custom/website/2.5.0/xsl/
/usr/share/xml/docbook/custom/website/2.5.0/xsl/ChangeLog
/usr/share/xml/docbook/custom/website/2.5.0/xsl/VERSION
/usr/share/xml/docbook/custom/website/2.5.0/xsl/autolayout.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/chunk-common.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/chunk-tabular.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/chunk-website.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/head.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/makefile-dep.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/olink.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/param.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/rss.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/tabular.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/toc-tabular.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/toc.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/website-common.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/website-targets.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/website.xsl
/usr/share/xml/docbook/custom/website/2.5.0/xsl/xbel.xsl