Drupal from 10.6.17 to 11.4.7

web/modules/custom/login_tracker/login_tracker.module

@@ -35,17 +35,17 @@ function login_tracker_user_login($account) {
   \Drupal::moduleHandler()->alter('login_tracker_login_data', $data, $account);
   $data = serialize($data);
 
-  $keys = [
-    'record_id' => NULL,
-  ];
   $fields = [
     'uid'             => $account->id(),
     'login_timestamp' => \Drupal::time()->getRequestTime(),
     'data'            => $data,
   ];
 
-  \Drupal::database()->merge('login_tracker')
-    ->key($keys)
+  // Core 11 narrowed Merge::key() to a string field, so the historical
+  // merge->key(['record_id' => NULL]) trick no longer works. A plain insert
+  // is exactly what it did (the NULL key never matched, forcing an insert
+  // per login).
+  \Drupal::database()->insert('login_tracker')
     ->fields($fields)
     ->execute();
 }