diff --git a/core/modules/field_ui/src/Tests/ManageFieldsTest.php b/core/modules/field_ui/src/Tests/ManageFieldsTest.php
index 24821e5..76328a5 100644
--- a/core/modules/field_ui/src/Tests/ManageFieldsTest.php
+++ b/core/modules/field_ui/src/Tests/ManageFieldsTest.php
@@ -626,19 +626,8 @@ public function testExternalDestinations() {
     $this->drupalPostForm('admin/structure/types/manage/article/fields/node.article.body/storage', [], 'Save field settings', $options);
     // The external redirect should not fire.
     $this->assertUrl('admin/structure/types/manage/article/fields/node.article.body/storage', $options);
-    $this->assertResponse(400);
-
-    foreach ($this->assertions as $id => $assertion) {
-      if ($assertion['status'] === 'exception') {
-        // Ensure that the right error is thrown.
-        $this->assertEqual('User error', $assertion['message_group']);
-        $this->assertEqual('Redirects to external URLs are not allowed by default, use \Drupal\Core\Routing\TrustedRedirectResponse for it.', $assertion['message']);
-        // Finally remove that exception entry in order to not fail the test
-        // itself.
-        unset($this->assertions[$id]);
-        $this->deleteAssert($assertion['message_id']);
-      }
-    }
+    $this->assertResponse(200);
+    $this->assertRaw('Attempt to update field <em class="placeholder">Body</em> failed: <em class="placeholder">The internal path component &quot;http://example.com&quot; is external. You are not allowed to specify an external URL together with internal:/.</em>.');
   }
 
   /**