diff --git a/src/Plugin/LanguageNegotiation/DomainLanguageNegotiation.php b/src/Plugin/LanguageNegotiation/DomainLanguageNegotiation.php
index a87e667a243e3c8f6cf4fcd53fa5b33dd4db9777..e4fc1b39c777bd5a1acbf1421a6d7ffeeb9689ea 100644
--- a/src/Plugin/LanguageNegotiation/DomainLanguageNegotiation.php
+++ b/src/Plugin/LanguageNegotiation/DomainLanguageNegotiation.php
@@ -51,7 +51,7 @@ class DomainLanguageNegotiation extends LanguageNegotiationMethodBase implements
    *
    * @var \Drupal\Core\Language\LanguageManagerInterface
    */
-  private $languageManager;
+  protected $languageManager;
 
   /**
    * Constructs a new LanguageNegotiationUserAdmin instance.