diff --git a/wp-includes/rest-api/endpoints/class-wp-rest-sidebars-controller.php b/wp-includes/rest-api/endpoints/class-wp-rest-sidebars-controller.php
index 4c1e82fbdb..3ab7dc993b 100644
--- a/wp-includes/rest-api/endpoints/class-wp-rest-sidebars-controller.php
+++ b/wp-includes/rest-api/endpoints/class-wp-rest-sidebars-controller.php
@@ -98,8 +98,10 @@ class WP_REST_Sidebars_Controller extends WP_REST_Controller {
 	 * @return WP_REST_Response|WP_Error Response object on success, or WP_Error object on failure.
 	 */
 	public function get_items( $request ) {
+		retrieve_widgets();
+
 		$data = array();
-		foreach ( (array) wp_get_sidebars_widgets() as $id => $widgets ) {
+		foreach ( wp_get_sidebars_widgets() as $id => $widgets ) {
 			$sidebar = $this->get_sidebar( $id );
 
 			if ( ! $sidebar ) {
@@ -135,6 +137,8 @@ class WP_REST_Sidebars_Controller extends WP_REST_Controller {
 	 * @return WP_REST_Response|WP_Error Response object on success, or WP_Error object on failure.
 	 */
 	public function get_item( $request ) {
+		retrieve_widgets();
+
 		$sidebar = $this->get_sidebar( $request['id'] );
 
 		if ( ! $sidebar ) {
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 2ceae67e68..e360e056eb 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.8-beta3-51234';
+$wp_version = '5.8-beta3-51235';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.