That's strange; the `head` and `footer` nodes were present in the XSL template this morning [1], last GH change was Feb 13 [2], what matches

    curl --head --silent --url https://xsl-website.widloski.com/template.xsl | grep modified
    last-modified: Thu, 13 Feb 2025 07:11:02 GMT

[1] at 09:11:48, according https://web.archive.org/web/*/http://xsl-website.widloski.co... [2] https://github.com/Evidlo/xsl-website/commits/master/templat...

The footer is in the stylesheet in both my and Evidlo's example. In neither of our examples are these in separate files from the stylesheet.