diff --git a/core/modules/migrate_drupal_ui/src/Form/MigrateUpgradeForm.php b/core/modules/migrate_drupal_ui/src/Form/MigrateUpgradeForm.php
index 810e02a..6e27268 100644
--- a/core/modules/migrate_drupal_ui/src/Form/MigrateUpgradeForm.php
+++ b/core/modules/migrate_drupal_ui/src/Form/MigrateUpgradeForm.php
@@ -69,7 +69,13 @@ class MigrateUpgradeForm extends ConfirmFormBase {
   protected $moduleHandler;
 
   /**
-   * List of modules that do not need an upgrade path.
+   * List of extensions that do not need an upgrade path.
+   *
+   * This property is an array where the keys are the version of Drupal from
+   * which we are upgrading and the values are arrays of extensions that do not
+   * need an upgrade path.
+   *
+   * @var array[]
    */
   protected $noUpgradePaths = [
     '6' => [
@@ -725,9 +731,9 @@ public function buildConfirmForm(array $form, FormStateInterface $form_state) {
     // Add source_module and destination_module for modules that do not need an
     // upgrade path and are enabled on the source site.
     $no_upgrade_paths = $form_state->get('no_upgrade_paths');
-    foreach ($no_upgrade_paths[$version] as $no_upgrade_path) {
-      if ($system_data['module'][$no_upgrade_path]['status']) {
-        $table_data[$no_upgrade_path]['core'][$no_upgrade_path] = $no_upgrade_path;
+    foreach ($no_upgrade_paths[$version] as $extension) {
+      if ($system_data['module'][$extension]['status']) {
+        $table_data[$extension]['core'][$extension] = $extension;
       }
     }
 
diff --git a/core/modules/migrate_drupal_ui/tests/modules/upgrade_form_alter_test/upgrade_form_alter_test.module b/core/modules/migrate_drupal_ui/tests/modules/upgrade_form_alter_test/upgrade_form_alter_test.module
index 36878fc..8855721 100644
--- a/core/modules/migrate_drupal_ui/tests/modules/upgrade_form_alter_test/upgrade_form_alter_test.module
+++ b/core/modules/migrate_drupal_ui/tests/modules/upgrade_form_alter_test/upgrade_form_alter_test.module
@@ -10,7 +10,7 @@
 /**
  * Implements hook_form_FORM_ID_alter().
  */
-function upgrade_form_alter_test_form_migrate_drupal_ui_form_alter(&$form, FormStateInterface $form_state, $form_id) {
+function upgrade_form_alter_test_form_migrate_drupal_ui_form_alter(array &$form, FormStateInterface $form_state, $form_id) {
   $no_upgrade_paths = $form_state->get('no_upgrade_paths');
   $no_upgrade_paths['6'][] = 'event';
   $no_upgrade_paths['7'][] = 'book';
diff --git a/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6Test.php b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6Test.php
index 5e3b83c..d8773e2 100644
--- a/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6Test.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/d6/MigrateUpgrade6Test.php
@@ -130,7 +130,7 @@ protected function getAvailablePaths() {
       'variable_admin',
       // To test that contrib modules can alter this list, Event is added here
       // by a hook_form_alter().
-      // See upgrade_form_alter_test_form_migrate_drupal_ui_form_alter().
+      // @see upgrade_form_alter_test_form_migrate_drupal_ui_form_alter().
       'event',
     ];
   }
@@ -142,8 +142,7 @@ protected function getMissingPaths() {
     return [
       // To test that contrib modules can alter this list, Event is removed from
       // here by a hook_form_alter().
-      // See upgrade_form_alter_test_form_migrate_drupal_ui_form_alter().
-      // 'event',
+      // @see upgrade_form_alter_test_form_migrate_drupal_ui_form_alter().
       'i18nblocks',
       'i18ncck',
       'i18ncontent',
diff --git a/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7Test.php b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7Test.php
index 0cbd239..c344c88 100644
--- a/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7Test.php
+++ b/core/modules/migrate_drupal_ui/tests/src/Functional/d7/MigrateUpgrade7Test.php
@@ -136,7 +136,7 @@ protected function getAvailablePaths() {
       'trigger',
       // To test that contrib modules can alter this list, Book is added here
       // by a hook_form_alter().
-      // See upgrade_form_alter_test_form_migrate_drupal_ui_form_alter().
+      // @see upgrade_form_alter_test_form_migrate_drupal_ui_form_alter().
       'book',
     ];
   }
@@ -148,8 +148,7 @@ protected function getMissingPaths() {
     return [
       // To test that contrib modules can alter this list, Book is removed from
       // here by a hook_form_alter().
-      // See upgrade_form_alter_test_form_migrate_drupal_ui_form_alter().
-      // 'book',
+      // @see upgrade_form_alter_test_form_migrate_drupal_ui_form_alter().
       'color',
       'rdf',
     ];