diff --git a/wp-includes/media.php b/wp-includes/media.php
index 57fae428fa..14428bacb3 100644
--- a/wp-includes/media.php
+++ b/wp-includes/media.php
@@ -2293,9 +2293,9 @@ function wp_embed_handler_googlevideo( $matches, $attr, $url, $rawattr ) {
 }
 
 /**
- * YouTube embed handler callback.
+ * YouTube iframe embed handler callback.
  *
- * Catches URLs that can be parsed but aren't supported by oEmbed.
+ * Catches YouTube iframe embed URLs that are not parsable by oEmbed but can be translated into a URL that is.
  *
  * @since 4.0.0
  *
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 8eac113ab1..b5bb7b734a 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.2-alpha-31017';
+$wp_version = '4.2-alpha-31018';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.