diff --git a/core/modules/comment/tests/src/Functional/CommentUserTest.php b/core/modules/comment/tests/src/Functional/CommentUserTest.php
index 216ebdf..b43c1a1 100644
--- a/core/modules/comment/tests/src/Functional/CommentUserTest.php
+++ b/core/modules/comment/tests/src/Functional/CommentUserTest.php
@@ -99,7 +99,7 @@ public function testUserCommenting() {
     $edit = [];
     $edit['subject[0][value]'] = 'I can comment on a user?';
     $this->submitForm($edit, t('Save'));
-    $this->assertSession()->addressEquals('/user/' . $this->adminUser->id() . '#comment-1');
+    $this->assertSession()->addressEquals($this->basePath . 'user/' . $this->adminUser->id() . '#comment-1');
     $this->assertSession()->pageTextContains('Your comment has been posted');
     $this->assertSession()->statusCodeEquals(200);
     $this->assertSession()->pageTextContains('I can comment on a user');
diff --git a/core/modules/simpletest/src/BrowserTestBase.php b/core/modules/simpletest/src/BrowserTestBase.php
index e0ece50..e7a8298 100644
--- a/core/modules/simpletest/src/BrowserTestBase.php
+++ b/core/modules/simpletest/src/BrowserTestBase.php
@@ -181,6 +181,13 @@
   protected $customTranslations;
 
   /**
+   * Base path for test environment.
+   *
+   * @var string
+   */
+  protected $basePath = '/';
+
+  /**
    * Mink session manager.
    *
    * @var \Behat\Mink\Mink
@@ -234,7 +241,7 @@ protected function setUp() {
     // Setup $_SERVER variable.
     $parsed_url = parse_url($base_url);
     $host = $parsed_url['host'] . (isset($parsed_url['port']) ? ':' . $parsed_url['port'] : '');
-    $path = isset($parsed_url['path']) ? rtrim(rtrim($parsed_url['path']), '/') : '';
+    $path = $this->basePath = isset($parsed_url['path']) ? rtrim(rtrim($parsed_url['path']), '/') : '';
     $port = isset($parsed_url['port']) ? $parsed_url['port'] : 80;
 
     // If the passed URL schema is 'https' then setup the $_SERVER variables