diff --git a/core/includes/install.core.inc b/core/includes/install.core.inc
index a6fa11d..10b92f5 100644
--- a/core/includes/install.core.inc
+++ b/core/includes/install.core.inc
@@ -1694,11 +1694,13 @@ function install_finished(&$install_state) {
   $snapshot = \Drupal::service('config.storage.snapshot');
   \Drupal::service('config.manager')->createSnapshot($active, $snapshot);
 
-  // Load current user and perform final login tasks.
-  // This has to be done after drupal_flush_all_caches()
-  // to avoid session regeneration.
-  $account = user_load(1);
-  user_login_finalize($account);
+  if ($install_state['interactive']) {
+    // Load current user and perform final login tasks.
+    // This has to be done after drupal_flush_all_caches()
+    // to avoid session regeneration.
+    $account = user_load(1);
+    user_login_finalize($account);
+  }
 
   // @todo Temporary hack to satisfy PIFR.
   // @see https://drupal.org/node/1317548
diff --git a/core/modules/simpletest/src/WebTestBase.php b/core/modules/simpletest/src/WebTestBase.php
index c382463..30a57da 100644
--- a/core/modules/simpletest/src/WebTestBase.php
+++ b/core/modules/simpletest/src/WebTestBase.php
@@ -909,11 +909,6 @@ protected function setUp() {
     chmod($directory, 0777);
 
     $request = \Drupal::request();
-    // If there is a session manager, close and save the session.
-    if (\Drupal::getContainer()->initialized('session_manager')) {
-      \Drupal::service('session_manager')->save();
-    }
-
     $this->kernel = DrupalKernel::createFromRequest($request, drupal_classloader(), 'prod', TRUE);
     $this->kernel->prepareLegacyRequest($request);
     // Force the container to be built from scratch instead of loaded from the