diff -r 34716fd837a4 -r be944660c56a wp/wp-includes/customize/class-wp-sidebar-block-editor-control.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-includes/customize/class-wp-sidebar-block-editor-control.php	Wed Sep 21 18:19:35 2022 +0200
@@ -0,0 +1,37 @@
+<?php
+/**
+ * Customize API: WP_Sidebar_Block_Editor_Control class.
+ *
+ * @package WordPress
+ * @subpackage Customize
+ * @since 5.8.0
+ */
+
+/**
+ * Core class used to implement the widgets block editor control in the
+ * customizer.
+ *
+ * @since 5.8.0
+ *
+ * @see WP_Customize_Control
+ */
+class WP_Sidebar_Block_Editor_Control extends WP_Customize_Control {
+	/**
+	 * The control type.
+	 *
+	 * @since 5.8.0
+	 *
+	 * @var string
+	 */
+	public $type = 'sidebar_block_editor';
+
+	/**
+	 * Render the widgets block editor container.
+	 *
+	 * @since 5.8.0
+	 */
+	public function render_content() {
+		// Render an empty control. The JavaScript in
+		// @wordpress/customize-widgets will do the rest.
+	}
+}