diff --git a/includes/settings.php b/includes/settings.php
index 28ad3a25f..8e86456e6 100644
--- a/includes/settings.php
+++ b/includes/settings.php
@@ -125,7 +125,11 @@ function update_notice( $plugin_file, $plugin_data, $status ) {
  * @since 1.2
  */
 function maybe_notice() {
-	if ( 0 === strpos( get_current_screen()->parent_base, 'distributor' ) ) {
+	$parent_base = get_current_screen()->parent_base;
+	if ( ! $parent_base ) {
+		return;
+	}
+	if ( 0 === strpos( $parent_base, 'distributor' ) ) {
 		if ( Utils\is_development_version() ) {
 			?>
 			<div class="notice notice-warning">
diff --git a/readme.txt b/readme.txt
index c611e18c9..f4a5fab65 100644
--- a/readme.txt
+++ b/readme.txt
@@ -1,7 +1,7 @@
 === Distributor ===
 Contributors:      10up
 Tags:              content, distribution, syndication, management
-Tested up to:      6.5
+Tested up to:      6.6
 Stable tag:        2.0.4
 License:           GPLv2 or later
 License URI:       http://www.gnu.org/licenses/gpl-2.0.html