diff --git a/core/themes/classy/classy.theme b/core/themes/classy/classy.theme
index b2e0a21..3b64a69 100644
--- a/core/themes/classy/classy.theme
+++ b/core/themes/classy/classy.theme
@@ -10,6 +10,11 @@
  */
 function classy_library_info_alter(&$libraries, $extension) {
   if ($extension == 'user' && isset($libraries['drupal.user'])) {
-    $libraries['drupal.user']['dependencies'][] = 'classy/user';
+    // @todo Replace with https://www.drupal.org/node/2497667 when possible.
+    $library_discovery = \Drupal::service('library.discovery');
+    $library = $library_discovery->getLibraryByName('classy', 'user');
+    foreach ($library['css'] as $css) {
+      $libraries['drupal.user']['css']['theme'][base_path() . $css['data']] = [];
+    }
   }
 }