diff --git a/includes/Core/Admin/Screens.php b/includes/Core/Admin/Screens.php
index 92bd0b16430..745c23fce33 100644
--- a/includes/Core/Admin/Screens.php
+++ b/includes/Core/Admin/Screens.php
@@ -367,7 +367,10 @@ private function get_screens() {
 					'render_callback'  => function( Context $context ) {
 						$is_view_only = ! $this->authentication->is_authenticated();
 
-						$setup_slug = htmlspecialchars( $context->input()->filter( INPUT_GET, 'slug' ) );
+						$setup_slug = $context->input()->filter( INPUT_GET, 'slug' );
+						if ( $setup_slug ) {
+							$setup_slug = htmlspecialchars( $setup_slug );
+						}
 						$reauth = $context->input()->filter( INPUT_GET, 'reAuth', FILTER_VALIDATE_BOOLEAN );
 						if ( $context->input()->filter( INPUT_GET, 'permaLink' ) ) {
 							?>