diff --git a/wp-includes/theme.php b/wp-includes/theme.php
index 0ffb22db04..8592ee50cf 100644
--- a/wp-includes/theme.php
+++ b/wp-includes/theme.php
@@ -2169,7 +2169,7 @@ function wp_customize_support_script() {
 <?php		endif; ?>
 
 			b[c] = b[c].replace( rcs, ' ' );
-			b[c] += ( window.postMessage && request ? ' ' : ' no-' ) + cs;
+			b[c] += ( window.postMessage && request && Array.prototype.indexOf ? ' ' : ' no-' ) + cs;
 		}());
 	</script>
 	<?php
diff --git a/wp-includes/version.php b/wp-includes/version.php
index cfe07e64f1..010b03046c 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.7-alpha-38626';
+$wp_version = '4.7-alpha-38627';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.