Index: src/wp-admin/edit.php
===================================================================
--- src/wp-admin/edit.php	(revision 43933)
+++ src/wp-admin/edit.php	(working copy)
@@ -183,8 +183,10 @@
 wp_enqueue_script('heartbeat');
 
 if ( 'wp_block' === $post_type ) {
-	wp_enqueue_script( 'wp-list-reusable-blocks' );
 	wp_enqueue_style( 'wp-list-reusable-blocks' );
+
+	// wp-list-reusable-blocks enhances the page's DOM and so needs to be loaded in the footer.
+	wp_enqueue_script( 'wp-list-reusable-blocks', '', array(), false, true );
 }
 
 $title = $post_type_object->labels->name;