diff --git a/core/modules/forum/src/Tests/ForumTest.php b/core/modules/forum/src/Tests/ForumTest.php
index 6feb754..ab53984 100644
--- a/core/modules/forum/src/Tests/ForumTest.php
+++ b/core/modules/forum/src/Tests/ForumTest.php
@@ -117,7 +117,7 @@ function testForum() {
     //Check that the basic forum install creates a default forum topic
     $this->drupalGet('/forum');
     // Look for the "General discussion" default forum
-    $this->assertRaw(t('<a href="'. Url::fromRoute('forum.page', ['taxonomy_term' => 1]) .'">General discussion</a>'), "Found the default forum at the /forum listing");
+    $this->assertRaw(t('<a href="'. Url::fromRoute('forum.page', ['taxonomy_term' => 1])->toString() .'">General discussion</a>'), "Found the default forum at the /forum listing");
 
     // Do the admin tests.
     $this->doAdminTests($this->admin_user);
diff --git a/core/modules/simpletest/src/WebTestBase.php b/core/modules/simpletest/src/WebTestBase.php
index 0b6b770..b6f7a23 100644
--- a/core/modules/simpletest/src/WebTestBase.php
+++ b/core/modules/simpletest/src/WebTestBase.php
@@ -1485,6 +1485,9 @@ protected function isInChildSite() {
    *   The retrieved HTML string, also available as $this->getRawContent()
    */
   protected function drupalGet($path, array $options = array(), array $headers = array()) {
+    if ($path instanceof Url) {
+      $path = $path->toString();
+    }
     // We re-using a CURL connection here. If that connection still has certain
     // options set, it might change the GET into a POST. Make sure we clear out
     // previous options.