diff --git a/core/modules/simpletest/src/TestBase.php b/core/modules/simpletest/src/TestBase.php
index d4018a7..9475715 100644
--- a/core/modules/simpletest/src/TestBase.php
+++ b/core/modules/simpletest/src/TestBase.php
@@ -1199,9 +1199,6 @@ private function restoreEnvironment() {
     }
     conf_path(TRUE, TRUE);
 
-    // Restore stream wrappers of the test runner.
-    $this->container->get('stream_wrapper_manager')->register();
-
     // Restore original shutdown callbacks.
     $callbacks = &drupal_register_shutdown_function();
     $callbacks = $this->originalShutdownCallbacks;
diff --git a/core/modules/simpletest/src/WebTestBase.php b/core/modules/simpletest/src/WebTestBase.php
index 6acca33..c11ddc8 100644
--- a/core/modules/simpletest/src/WebTestBase.php
+++ b/core/modules/simpletest/src/WebTestBase.php
@@ -915,6 +915,11 @@ protected function setUp() {
     $this->resetAll();
     $this->kernel->prepareLegacyRequest($request);
 
+    // Explicitly call register() again on the container registered in \Drupal.
+    // @todo This should already be called through
+    //   DrupalKernel::prepareLegacyRequest() -> DrupalKernel::boot() but that
+    //   appears to be calling a different container.
+    $this->container->get('stream_wrapper_manager')->register();
     // Temporary fix so that when running from run-tests.sh we don't get an
     // empty current path which would indicate we're on the home page.
     $path = current_path();