only in patch2:
unchanged:
--- a/panels_ipe/panels_ipe.api.php
+++ b/panels_ipe/panels_ipe.api.php
@@ -26,3 +26,22 @@ function hook_panels_ipe_panels_display_presave(PanelsDisplayVariant $panels_dis
     $panels_display->setStorage('custom_storage_key', $configuration['storage_id']);
   }
 }
+
+/**
+ * Change the tempstore ID used by Panels IPE.
+ *
+ * Changes made to a Panels display using the IPE are stored in a shared
+ * temporary storage object (tempstore) until the display either saved or
+ * reverted to its previous state. This hook allows one to specify a different
+ * key for storing changes in the tempstore.
+ *
+ * @param string $id
+ *   The tempstore ID, passed by reference.
+ * @param \Drupal\panels\Plugin\DisplayVariant\PanelsDisplayVariant $panels_display
+ *   The Panels display for which the tempstore ID will be used.
+ */
+function hook_panels_ipe_tempstore_id_alter(&$id, PanelsDisplayVariant $panels_display) {
+  if ($panels_display->getBuilder()->getPluginId() == 'panelizer') {
+    $id = 'panelizer';
+  }
+}