diff --git a/typo3/sysext/lang/Classes/Command/LanguageCommandController.php b/typo3/sysext/lang/Classes/Command/LanguageCommandController.php
index e91f42083dcfd7eabcd1ffed0e1479350a340051..ba4d53b4f37c3fbcdbd227ac1dc46e55a2adf892 100644
--- a/typo3/sysext/lang/Classes/Command/LanguageCommandController.php
+++ b/typo3/sysext/lang/Classes/Command/LanguageCommandController.php
@@ -14,6 +14,7 @@ namespace TYPO3\CMS\Lang\Command;
  * The TYPO3 project - inspiring people to share!
  */
 
+use TYPO3\CMS\Core\Cache\CacheManager;
 use TYPO3\CMS\Core\Package\PackageInterface;
 use TYPO3\CMS\Core\Package\PackageManager;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
@@ -93,6 +94,8 @@ class LanguageCommandController extends CommandController
                 $this->output->progressAdvance();
             }
         }
+        // Flush language cache
+        GeneralUtility::makeInstance(CacheManager::class)->getCache('l10n')->flush();
         $this->output->progressFinish();
     }
 
diff --git a/typo3/sysext/lang/Classes/Controller/LanguageController.php b/typo3/sysext/lang/Classes/Controller/LanguageController.php
index 9a2bb7adf5cc62acbf91093971f706fd572b09f2..37c916d57b3e6e4c78d16358b964b980a314889d 100644
--- a/typo3/sysext/lang/Classes/Controller/LanguageController.php
+++ b/typo3/sysext/lang/Classes/Controller/LanguageController.php
@@ -18,6 +18,7 @@ use TYPO3\CMS\Backend\Template\Components\ButtonBar;
 use TYPO3\CMS\Backend\Template\Components\Menu\Menu;
 use TYPO3\CMS\Backend\Template\Components\Menu\MenuItem;
 use TYPO3\CMS\Backend\View\BackendTemplateView;
+use TYPO3\CMS\Core\Cache\CacheManager;
 use TYPO3\CMS\Core\Imaging\Icon;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Extbase\Mvc\Controller\ActionController;
@@ -180,6 +181,8 @@ class LanguageController extends ActionController
             $response['progress'] = $progress > 100 ? 100 : $progress;
         }
         $this->view->assign('response', $response);
+        // Flush language cache
+        GeneralUtility::makeInstance(CacheManager::class)->getCache('l10n')->flush();
     }
 
     /**
@@ -201,6 +204,8 @@ class LanguageController extends ActionController
             }
         }
         $this->view->assign('response', $response);
+        // Flush language cache
+        GeneralUtility::makeInstance(CacheManager::class)->getCache('l10n')->flush();
     }
 
     /**