diff --git a/config/sets/twig/composer-based.php b/config/sets/twig/composer-based.php
index e818ffb1..919d3d76 100644
--- a/config/sets/twig/composer-based.php
+++ b/config/sets/twig/composer-based.php
@@ -239,6 +239,7 @@
         'Twig_TokenParser_Deprecated' => 'Twig\TokenParser\DeprecatedTokenParser',
         'Twig_Util_DeprecationCollector' => 'Twig\Util\DeprecationCollector',
         'Twig_Util_TemplateDirIterator' => 'Twig\Util\TemplateDirIterator',
+        'Twig_Tests_EnvironmentTest_Extension' => 'Twig\Tests\EnvironmentTest\Extension',
     ], 'twig/twig', '>=1.40');
 
     // twig/twig 3.0
diff --git a/config/sets/twig/twig-underscore-to-namespace.php b/config/sets/twig/twig-underscore-to-namespace.php
index 8812673b..04c71f47 100644
--- a/config/sets/twig/twig-underscore-to-namespace.php
+++ b/config/sets/twig/twig-underscore-to-namespace.php
@@ -190,5 +190,5 @@
     'Twig_TokenParser_Deprecated' => 'Twig\\TokenParser\\DeprecatedTokenParser',
     'Twig_Util_DeprecationCollector' => 'Twig\\Util\\DeprecationCollector',
     'Twig_Util_TemplateDirIterator' => 'Twig\\Util\\TemplateDirIterator',
-    'Twig_Tests_EnvironmentTest_Extension' => 'Twig\\Tests\\EnvironmentTest\\Extensio',
+    'Twig_Tests_EnvironmentTest_Extension' => 'Twig\\Tests\\EnvironmentTest\\Extension',
 ]);