fix navi highlight of instances

classes/cronlog-renderer.class.php

@@ -348,7 +348,7 @@ class cronlogrenderer extends cronlog
             return '';
         }
         $sReturn = '';
-        $sServer = isset($_SERVER['SERVER_NAME']) ?? false;
+        $sServer = $_SERVER['SERVER_NAME'] ?: false;
         $sReturn .= '<li class="nav-item"><a class="nav-link nav-link" data-widget="pushmenu" href="#" role="button"><i class="fas fa-bars"></i></a></li>'
             . '<li class="nav-item d-none d-sm-inline-block"><a href="#" class="nav-link">' . $this->t('instances') . ':</a></li>';