diff --git a/core/modules/language/config/language.mappings.yml b/core/modules/language/config/language.mappings.yml
index 03a6569..39d7a66 100644
--- a/core/modules/language/config/language.mappings.yml
+++ b/core/modules/language/config/language.mappings.yml
@@ -3,7 +3,5 @@
 zh-tw: zh-hant # Taiwan Chinese in traditional script
 zh-hk: zh-hant # Hong Kong Chinese in traditional script
 zh-mo: zh-hant # Macao Chinese in traditional script
-zh-cht: zh-hant # traditional Chinese
 zh-cn: zh-hans # PRC Mainland Chinese in simplified script
 zh-sg: zh-hans # Singapore Chinese in simplified script
-zh-chs: zh-hans # simplified Chinese
diff --git a/core/modules/language/lib/Drupal/language/Tests/LanguageBrowserDetectionUnitTest.php b/core/modules/language/lib/Drupal/language/Tests/LanguageBrowserDetectionUnitTest.php
index c8c5cce..7189240 100644
--- a/core/modules/language/lib/Drupal/language/Tests/LanguageBrowserDetectionUnitTest.php
+++ b/core/modules/language/lib/Drupal/language/Tests/LanguageBrowserDetectionUnitTest.php
@@ -149,8 +149,6 @@ class LanguageBrowserDetectionUnitTest extends WebTestBase {
       'zh-mo' => 'zh-hant',
       'zh-hans' => 'zh-hans',
       'zh-hant' => 'zh-hant',
-      'zh-chs' => 'zh-hans',
-      'zh-cht' => 'zh-hant',
     );
 
     foreach ($test_cases as $accept_language => $expected_result) {