diff --git a/core/lib/Drupal/Core/Asset/LibraryDependencyResolver.php b/core/lib/Drupal/Core/Asset/LibraryDependencyResolver.php
index e4c5d6d15cce3dc..95fca186614fc94 100644
--- a/core/lib/Drupal/Core/Asset/LibraryDependencyResolver.php
+++ b/core/lib/Drupal/Core/Asset/LibraryDependencyResolver.php
@@ -65,8 +65,6 @@ class LibraryDependencyResolver implements LibraryDependencyResolverInterface {
    * {@inheritdoc}
    */
   public function getMinimalRepresentativeSubset(array $libraries) {
-    assert('count($libraries) === count(array_unique($libraries))', '$libraries can\'t contain duplicate items.');
-
     $minimal = [];
 
     // Determine each library's dependencies.
diff --git a/core/modules/system/system.module b/core/modules/system/system.module
index 15138a10e574163..d08e1016c816ccc 100644
--- a/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -766,10 +766,10 @@ function system_js_settings_alter(&$settings, AttachedAssetsInterface $assets) {
     }
     // Provide the page with information about the individual asset libraries
     // used, information not otherwise available when aggregation is enabled.
-    $minimal_libraries = $library_dependency_resolver->getMinimalRepresentativeSubset(array_unique(array_merge(
+    $minimal_libraries = $library_dependency_resolver->getMinimalRepresentativeSubset(array_merge(
       $assets->getLibraries(),
       $assets->getAlreadyLoadedLibraries()
-    )));
+    ));
     sort($minimal_libraries);
     $settings['ajaxPageState']['libraries'] = implode(',', $minimal_libraries);
   }
diff --git a/core/tests/Drupal/Tests/Core/Asset/LibraryDependencyResolverTest.php b/core/tests/Drupal/Tests/Core/Asset/LibraryDependencyResolverTest.php
index 6e499d9eaaeadc5..40e18210800ba98 100644
--- a/core/tests/Drupal/Tests/Core/Asset/LibraryDependencyResolverTest.php
+++ b/core/tests/Drupal/Tests/Core/Asset/LibraryDependencyResolverTest.php
@@ -169,12 +169,4 @@ class LibraryDependencyResolverTest extends UnitTestCase {
     $this->assertEquals($expected, $this->libraryDependencyResolver->getMinimalRepresentativeSubset($libraries));
   }
 
-  /**
-   * @covers ::getMinimalRepresentativeSubset
-   */
-  public function testGetMinimalRepresentativeSubsetInvalidInput() {
-    $this->setExpectedException(\AssertionError::class, '$libraries can\'t contain duplicate items.');
-    $this->libraryDependencyResolver->getMinimalRepresentativeSubset(['test/no_deps_a', 'test/no_deps_a']);
-  }
-
 }