libxml update on Linux systems changes behavior of DOMDocument->loadHTML #24349

<?php
	public function clean($html)
	{
...
                $doc = new \DOMDocument();
		$doc->loadHTML(
			'<?xml encoding="utf-8" ?><body>'. $valid .'</body>',
			LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD
		);
		
		$this->cleanNode($doc->getElementsByTagName('body')->item(0));

		$doc->formatOutput = true;
		$filtered = $doc->saveHTML();
		
		$clean = str_replace(array('<?xml encoding="utf-8" ?><body>', '</body>'), '', $filtered);
...
}