diff --git a/wp-admin/custom-background.php b/wp-admin/custom-background.php
index c9ba796463..2691408e50 100644
--- a/wp-admin/custom-background.php
+++ b/wp-admin/custom-background.php
@@ -386,7 +386,8 @@ if ( current_theme_supports( 'custom-background', 'default-color' ) )
 		$thumbnail = wp_get_attachment_image_src( $id, 'thumbnail' );
 		set_theme_mod('background_image_thumb', esc_url_raw( $thumbnail[0] ) );
 
-		do_action('wp_create_file_in_uploads', $file, $id); // For replication
+		//duplicate_hook
+		do_action( 'wp_create_file_in_uploads', $file, $id ); // For replication
 		$this->updated = true;
 	}
 
@@ -411,6 +412,7 @@ if ( current_theme_supports( 'custom-background', 'default-color' ) )
 	public function wp_set_background_image() {
 		if ( ! current_user_can('edit_theme_options') || ! isset( $_POST['attachment_id'] ) ) exit;
 		$attachment_id = absint($_POST['attachment_id']);
+		//duplicate_hook
 		$sizes = array_keys(apply_filters( 'image_size_names_choose', array('thumbnail' => __('Thumbnail'), 'medium' => __('Medium'), 'large' => __('Large'), 'full' => __('Full Size')) ));
 		$size = 'thumbnail';
 		if ( in_array( $_POST['size'], $sizes ) )