code: private function isThemeSwitcherEnabled()
      {
          /** @var \common_ext_ExtensionsManager $extensionsManager */
          $extensionsManager = $this->getServiceLocator()->get(\common_ext_ExtensionsManager::SERVICE_ID);
          $config = $extensionsManager->getExtensionById("taoTests")->getConfig("test_runner_plugin_registry");
  
          return array_key_exists(self::TOOL_ITEM_THEME_SWITCHER_KEY, $config)
              && $config[self::TOOL_ITEM_THEME_SWITCHER_KEY]["active"] === true;
      }
docs: Returns that the Theme Switcher Plugin is enabled or not
  
  @return bool
  @throws \common_ext_ExtensionException