diff --git a/wp-admin/includes/post.php b/wp-admin/includes/post.php
index 3e7e333fbe..86ba666f38 100644
--- a/wp-admin/includes/post.php
+++ b/wp-admin/includes/post.php
@@ -1419,8 +1419,7 @@ function _wp_post_thumbnail_html( $thumbnail_id = null, $post = null ) {
 
 		$thumbnail_html = wp_get_attachment_image( $thumbnail_id, $size );
 
-		if ( !empty( $thumbnail_html ) ) {
-			$ajax_nonce = wp_create_nonce( 'set_post_thumbnail-' . $post->ID );
+		if ( ! empty( $thumbnail_html ) ) {
 			$content = sprintf( $set_thumbnail_link,
 				esc_url( $upload_iframe_src ),
 				' aria-describedby="set-post-thumbnail-desc"',
diff --git a/wp-includes/version.php b/wp-includes/version.php
index b1fe963f39..42dc19747f 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.6-beta4-38136';
+$wp_version = '4.6-beta4-38137';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.