diff --git a/wp-admin/includes/network.php b/wp-admin/includes/network.php
index 562a733770..07969ff222 100644
--- a/wp-admin/includes/network.php
+++ b/wp-admin/includes/network.php
@@ -445,7 +445,7 @@ function network_step2( $errors = false ) {
 		$notice_message = '<strong>' . __( 'Caution:' ) . '</strong> ';
 		$notice_args    = array(
 			'type'               => 'warning',
-			'additional_classes' => 'inline',
+			'additional_classes' => array( 'inline' ),
 		);
 
 		if ( file_exists( $home_path . '.htaccess' ) ) {
diff --git a/wp-includes/version.php b/wp-includes/version.php
index b86758101c..af14d01be8 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.4-alpha-56409';
+$wp_version = '6.4-alpha-56410';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.