/usr/share/yelp-xsl/xslt/mallard/html/ is in yelp-xsl 3.10.1-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-api.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-block.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-facets.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-gloss.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-inline.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-links.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-list.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-math.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-media.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-page.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-svg.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-table.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html-ui.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2html.xsl
/usr/share/yelp-xsl/xslt/mallard/html/mal2xhtml.xsl