diff --git a/resources/lang/sl_SI/validation.php b/resources/lang/sl_SI/validation.php
index b73aa097d2..fff91fb426 100644
--- a/resources/lang/sl_SI/validation.php
+++ b/resources/lang/sl_SI/validation.php
@@ -1,4 +1,6 @@
 <?php
+declare(strict_types=1);
+
 /**
  * validation.php
  * Copyright (C) 2016 thegrumpydictator@gmail.com