// Warm the page cache.
$this->drupalGet('');
$this->assertNoText('Powered by Drupal');
- $this->assertNoCacheTag('config:block_list');
+ $this->assertSession()->responseHeaderNotContains('X-Drupal-Cache-Tags', 'config:block_list');
// Install the block module, and place the "Powered by Drupal" block.
$this->container->get('module_installer')->install(['block', 'shortcut']);