36 files declare their use of ConfigEntityType

Action.php in core/modules/system/src/Entity/Action.php
BaseFieldOverride.php in core/lib/Drupal/Core/Field/Entity/BaseFieldOverride.php
Block.php in core/modules/block/src/Entity/Block.php
BlockContentType.php in core/modules/block_content/src/Entity/BlockContentType.php
CommentType.php in core/modules/comment/src/Entity/CommentType.php
ConfigQueryTest.php in core/modules/config/tests/config_test/src/Entity/ConfigQueryTest.php
ConfigTest.php in core/modules/config/tests/config_test/src/Entity/ConfigTest.php
ConfigurableLanguage.php in core/modules/language/src/Entity/ConfigurableLanguage.php
ContactForm.php in core/modules/contact/src/Entity/ContactForm.php
ContentLanguageSettings.php in core/modules/language/src/Entity/ContentLanguageSettings.php
DateFormat.php in core/lib/Drupal/Core/Datetime/Entity/DateFormat.php
Editor.php in core/modules/editor/src/Entity/Editor.php
EntityFormDisplay.php in core/lib/Drupal/Core/Entity/Entity/EntityFormDisplay.php
EntityFormMode.php in core/lib/Drupal/Core/Entity/Entity/EntityFormMode.php
EntityTestBundle.php in core/modules/system/tests/modules/entity_test/src/Entity/EntityTestBundle.php
EntityTestMulBundle.php in core/modules/system/tests/modules/entity_test/src/Entity/EntityTestMulBundle.php
EntityTestNoIdBundle.php in core/modules/system/tests/modules/entity_test/src/Entity/EntityTestNoIdBundle.php
EntityViewDisplay.php in core/lib/Drupal/Core/Entity/Entity/EntityViewDisplay.php
EntityViewMode.php in core/lib/Drupal/Core/Entity/Entity/EntityViewMode.php
FieldConfig.php in core/modules/field/src/Entity/FieldConfig.php
FieldStorageConfig.php in core/modules/field/src/Entity/FieldStorageConfig.php
FilterFormat.php in core/modules/filter/src/Entity/FilterFormat.php
ImageStyle.php in core/modules/image/src/Entity/ImageStyle.php
MediaType.php in core/modules/media/src/Entity/MediaType.php
Menu.php in core/modules/system/src/Entity/Menu.php
NodeType.php in core/modules/node/src/Entity/NodeType.php
ResponsiveImageStyle.php in core/modules/responsive_image/src/Entity/ResponsiveImageStyle.php
RestResourceConfig.php in core/modules/rest/src/Entity/RestResourceConfig.php
Role.php in core/modules/user/src/Entity/Role.php
SearchPage.php in core/modules/search/src/Entity/SearchPage.php
ShortcutSet.php in core/modules/shortcut/src/Entity/ShortcutSet.php
TestConfigType.php in core/modules/system/tests/modules/module_installer_config_test/src/Entity/TestConfigType.php
View.php in core/modules/views/src/Entity/View.php
ViewsConfigEntityTest.php in core/modules/views/tests/modules/views_config_entity_test/src/Entity/ViewsConfigEntityTest.php
Vocabulary.php in core/modules/taxonomy/src/Entity/Vocabulary.php
Workflow.php in core/modules/workflows/src/Entity/Workflow.php

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