diff --git a/api/src/Mail/Html.php b/api/src/Mail/Html.php
index ee582a620d..9f134cdd89 100644
--- a/api/src/Mail/Html.php
+++ b/api/src/Mail/Html.php
@@ -500,9 +500,12 @@ class Html
 			LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD | LIBXML_NOBLANKS
 		))
 		{
+			// do not sent possible xml errors in buffer further otherwise it may get caught as et2 template error in Widget
+			libxml_clear_errors();
 			// Failed to parse
 			return $html;
 		}
+
 		$dom->normalizeDocument();
 
 		foreach(array('ol','ul') as $list_type)
@@ -531,6 +534,9 @@ class Html
 		}
 		$dom->removeChild($dom->firstChild);
 
+		// do not sent possible xml errors in buffer further otherwise it may get caught as et2 template error in Widget
+		libxml_clear_errors();
+
 		return $dom->saveHTML();
 	}