https://bugs.gentoo.org/897680
This fixes an error you get under php-8.1 when "$server->getContainer($base->getDN())"
returns a null object (that's the case if you have a short, one component, rootdn in your
"$servers->setValue('server','base',array(...)" config.
--- a/lib/HTMLTree.php
+++ b/lib/HTMLTree.php
@@ -98,7 +98,7 @@
$this->javascript .= '