diff --git a/core/lib/Drupal/Core/Asset/LibraryDiscovery.php b/core/lib/Drupal/Core/Asset/LibraryDiscovery.php
index 37e35e10e2e14ca632e793cc1bcdb8dc5673af80..b1d0969aa7333716fd31d683aad214a096eb4f7e 100644
--- a/core/lib/Drupal/Core/Asset/LibraryDiscovery.php
+++ b/core/lib/Drupal/Core/Asset/LibraryDiscovery.php
@@ -49,7 +49,6 @@ public function getLibrariesByExtension($extension) {
       $libraries = $this->collector->get($extension);
       $this->libraryDefinitions[$extension] = [];
       foreach ($libraries as $name => $definition) {
-        $library_name = "$extension/$name";
         $this->libraryDefinitions[$extension][$name] = $definition;
       }
     }