diff --git a/wp-includes/class-wp-theme.php b/wp-includes/class-wp-theme.php
index 8b3661a888..f161a63186 100644
--- a/wp-includes/class-wp-theme.php
+++ b/wp-includes/class-wp-theme.php
@@ -1038,7 +1038,7 @@ final class WP_Theme implements ArrayAccess {
 				}
 
 				foreach ( $types as $type ) {
-					$type = trim( $type );
+					$type = sanitize_key( $type );
 					if ( ! isset( $post_templates[ $type ] ) ) {
 						$post_templates[ $type ] = array();
 					}
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 11dd2d9e0f..ab9bd12aac 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.7-beta3-39235';
+$wp_version = '4.7-beta3-39236';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.