ImmutableConfig

class \Drupal\Core\Config\ConfigBase implements \Drupal\Core\Cache\RefinableCacheableDependencyInterface uses \Drupal\Core\DependencyInjection\DependencySerializationTrait, \Drupal\Core\Cache\RefinableCacheableDependencyTrait
- class \Drupal\Core\Config\StorableConfigBase extends \Drupal\Core\Config\ConfigBase
  - class \Drupal\Core\Config\Config extends \Drupal\Core\Config\StorableConfigBase
    - class \Drupal\Core\Config\ImmutableConfig extends \Drupal\Core\Config\Config
  - class \Drupal\language\Config\LanguageConfigOverride extends \Drupal\Core\Config\StorableConfigBase uses \Drupal\language\Config\LanguageConfigCollectionNameTrait
- class \Drupal\Core\Theme\ThemeSettings extends \Drupal\Core\Config\ConfigBase

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