diff -u b/core/modules/taxonomy/tests/src/Functional/VocabularyPermissionsTest.php b/core/modules/taxonomy/tests/src/Functional/VocabularyPermissionsTest.php
--- b/core/modules/taxonomy/tests/src/Functional/VocabularyPermissionsTest.php
+++ b/core/modules/taxonomy/tests/src/Functional/VocabularyPermissionsTest.php
@@ -288,7 +288,7 @@
 
     $this->drupalPostForm(NULL, $edit, t('Save'));
     // Ensure form redirected back to overview.
-    $this->assertUrl('admin/structure/taxonomy/manage/' . $vocabulary->id() . '/overview');
+    $this->assertSession()->addressEquals('admin/structure/taxonomy/manage/' . $vocabulary->id() . '/overview');
     $assert_session->pageTextContains(t('Created new term @name.', ['@name' => $edit['name[0][value]']]));
 
     $terms = \Drupal::entityTypeManager()