--- a/modules/ds_switch_view_mode/ds_switch_view_mode.module
+++ b/modules/ds_switch_view_mode/ds_switch_view_mode.module
@@ -119,9 +119,9 @@

       $mode = $form_state->getValue('ds_switch');
       if (!$mode) {
-        $mode = $node->get('ds_switch')->value;
+        $mode = $node->get('ds_switch')->value ?? '';
       }
-      $chosen_layout = $layouts[$mode];
+      $chosen_layout = $layouts[$mode] ?? NULL;
       if (empty($chosen_layout)) {
         $chosen_layout = $layouts['full'] ?? $layouts[''];
       }