I couldn’t get the PHx to work with the WayFinder, instead I modified wayfinder.inc.php (found in assets/snippets/wayfinder/)
On line 181 you will find this code:
$phArray = array($useSub,$useClass,$classNames,$resource['link'],$resource['title'],$resource['linktext'],$useId,$resource['link_attributes'],$resource['id'],$resource['introtext'],$resource['description'],$numChildren);
I changed this to:
$phArray = array($useSub,$useClass,$classNames,$resource['link'],htmlspecialchars($resource['title']),htmlspecialchars($resource['linktext']),$useId,$resource['link_attributes'],$resource['id'],htmlspecialchars($resource['introtext']),htmlspecialchars($resource['description']),$numChildren);