9 files declare their use of ConfigCrudEvent in Zircon Profile 8

ConfigCacheTag.php in core/modules/system/src/EventSubscriber/ConfigCacheTag.php

Contains \Drupal\system\EventSubscriber\ConfigCacheTag.

ConfigSchemaChecker.php in core/lib/Drupal/Core/Config/Testing/ConfigSchemaChecker.php

Contains \Drupal\Core\Config\Testing\ConfigSchemaChecker.

ConfigSubscriber.php in core/modules/language/src/EventSubscriber/ConfigSubscriber.php

Contains \Drupal\language\EventSubscriber\ConfigSubscriber.

EventSubscriber.php in core/modules/config/tests/config_import_test/src/EventSubscriber.php

Contains \Drupal\config_import_test\EventSubscriber.

EventSubscriber.php in core/modules/config/tests/config_events_test/src/EventSubscriber.php

Contains \Drupal\config_events_test\EventSubscriber.

LanguageConfigFactoryOverride.php in core/modules/language/src/Config/LanguageConfigFactoryOverride.php

Contains \Drupal\language\Config\LanguageConfigFactoryOverride.

LocaleConfigSubscriber.php in core/modules/locale/src/LocaleConfigSubscriber.php

Contains \Drupal\locale\LocaleConfigSubscriber.

QueryFactory.php in core/lib/Drupal/Core/Config/Entity/Query/QueryFactory.php

Contains \Drupal\Core\Config\Entity\Query\QueryFactory.

SystemConfigSubscriber.php in core/modules/system/src/SystemConfigSubscriber.php

Contains \Drupal\system\SystemConfigSubscriber.