Issue #3240959 by andypost, alexpott:...

Issue #3240959 by andypost, alexpott: \Drupal\migrate_drupal_ui\Form\ReviewForm::prepareOutput() causes deprecations on PHP 8.1

core/modules/migrate_drupal_ui/src/Form/ReviewForm.php

@@ -284,7 +284,10 @@ public function getConfirmText() {
   protected function prepareOutput(array $migration_state) {
     $output = [];
     foreach ($migration_state as $source_machine_name => $destination_modules) {
-      $data = unserialize($this->systemData['module'][$source_machine_name]['info']);
+      $data = NULL;
+      if (isset($this->systemData['module'][$source_machine_name]['info'])) {
+        $data = unserialize($this->systemData['module'][$source_machine_name]['info']);
+      }
       $source_module_name = $data['name'] ?? $source_machine_name;
       // Get the names of all the destination modules.
       $destination_module_names = [];