Expanded class hierarchy of CssCollectionOptimizer in Drupal 8
- class \Drupal\Core\Asset\CssCollectionOptimizer implements AssetCollectionOptimizerInterface
- class \Drupal\advagg\Asset\CssCollectionOptimizer implements AssetCollectionOptimizerInterface
- class \Drupal\flysystem\Asset\CssCollectionOptimizer uses SchemeExtensionTrait