diff --git a/wp-includes/load.php b/wp-includes/load.php
index 02bf0299bf..9780519856 100644
--- a/wp-includes/load.php
+++ b/wp-includes/load.php
@@ -948,6 +948,10 @@ function wp_get_active_and_valid_themes() {
 		return $themes;
 	}
 
+	if ( ! wp_using_themes() ) {
+		return $themes;
+	}
+
 	if ( TEMPLATEPATH !== STYLESHEETPATH ) {
 		$themes[] = STYLESHEETPATH;
 	}
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 70984b1d30..c9aafc73cb 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.3-alpha-55889';
+$wp_version = '6.3-alpha-55890';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.