diff --git a/htdocs/core/lib/functions.lib.php b/htdocs/core/lib/functions.lib.php
index d150e866f0262..3403a95d269b3 100644
--- a/htdocs/core/lib/functions.lib.php
+++ b/htdocs/core/lib/functions.lib.php
@@ -7648,7 +7648,11 @@ function dol_string_onlythesehtmlattributes($stringtoclean, $allowed_attributes
 
 		// Warning: loadHTML does not support HTML5 on old libxml versions.
 		$dom = new DOMDocument('', 'UTF-8');
+		// If $stringtoclean is wrong, it will generates warnings. So we disable warnings and restore them later.
+		$savwarning = error_reporting();
+		error_reporting(E_ALL & ~E_WARNING & ~E_NOTICE);
 		$dom->loadHTML($stringtoclean, LIBXML_ERR_NONE | LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD | LIBXML_NONET | LIBXML_NOWARNING | LIBXML_NOXMLDECL);
+		error_reporting($savwarning);
 
 		if ($dom instanceof DOMDocument) {
 			for ($els = $dom->getElementsByTagname('*'), $i = $els->length - 1; $i >= 0; $i--) {