13 files declare their use of ConfigManagerInterface in Drupal 8

BundleConfigImportValidate.php in core/lib/Drupal/Core/Entity/Event/BundleConfigImportValidate.php

ConfigController.php in core/modules/config/src/Controller/ConfigController.php

ConfigDependencyDeleteFormTrait.php in core/lib/Drupal/Core/Config/Entity/ConfigDependencyDeleteFormTrait.php

ConfigEntityStorageTest.php in core/tests/Drupal/Tests/Core/Config/Entity/ConfigEntityStorageTest.php

ConfigImportSubscriber.php in core/modules/content_moderation/src/EventSubscriber/ConfigImportSubscriber.php

ConfigSingleImportForm.php in core/modules/config/src/Form/ConfigSingleImportForm.php

ConfigSnapshotSubscriber.php in core/lib/Drupal/Core/EventSubscriber/ConfigSnapshotSubscriber.php

ConfigSync.php in core/modules/config/src/Form/ConfigSync.php

ExcludedModulesEventSubscriber.php in core/lib/Drupal/Core/EventSubscriber/ExcludedModulesEventSubscriber.php

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

ModulesUninstallConfirmForm.php in core/modules/system/src/Form/ModulesUninstallConfirmForm.php

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

ThemeInstaller.php in core/lib/Drupal/Core/Extension/ThemeInstaller.php