To overcome the two problems here (client side loading the template and ending browser support) you could throw in php in the mix and have a wonderful solution for templating with bullet proof standards: // XML $xml_doc = new DOMDocument(); $xml_doc->load("file1.xml");

// XSL $xsl_doc = new DOMDocument(); $xsl_doc->load("file.xsl");

// Proc $proc = new XSLTProcessor(); $proc->importStylesheet($xsl_doc); $newdom = $proc->transformToDoc($xml_doc);

// Output print $newdom->saveXML();

XSLT lacks functionality? No problem, use php functions in xslt: https://www.php.net/manual/en/class.xsltprocessor.php

What you're describing is basically Symphony, the CMS built around XSLT with some PHP and MySQL to glue things together: https://github.com/symphonycms/symphonycms

I don't think it's been updated since 2019. XSL was really powerful, but it had a steep learning curve, and I think server-side PHP and client-side JS were just more intuitive.