diff --git a/wp-includes/l10n.php b/wp-includes/l10n.php
index 0ad4e01ba7..4ae7e2d278 100644
--- a/wp-includes/l10n.php
+++ b/wp-includes/l10n.php
@@ -92,7 +92,7 @@ function get_user_locale( $user_id = 0 ) {
 		$user = wp_get_current_user();
 	} elseif ( $user_id instanceof WP_User ) {
 		$user = $user_id;
-	} elseif ( is_numeric( $user_id ) ) {
+	} elseif ( $user_id && is_numeric( $user_id ) ) {
 		$user = get_user_by( 'id', $user_id );
 	}
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 8bed6e0ab1..1220ded253 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.7-beta1-39133';
+$wp_version = '4.7-beta1-39134';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.