Ticket #39589: 39589_b.patch

wp-admin/upload.php

@@ -167 +167 @@
                         break;
                 default:
                         /** This action is documented in wp-admin/edit-comments.php */
-                        $location = apply_filters( 'handle_bulk_actions-' . get_current_screen()->id, $location, $doaction, $post_ids );
+                        if ( ! isset( $post_ids ) ) {
+                                $post_ids = array();
+                        }
+                        $location = apply_filters( 'handle_bulk_actions-' . get_current_screen()->id, $location, $doaction, (array) $post_ids );
         }
 
         wp_redirect( $location );