29 files declare their use of ContentEntityTypeInterface

CommentStorageSchema.php in core/modules/comment/src/CommentStorageSchema.php
ConfigImportAllTest.php in core/modules/config/tests/src/Functional/ConfigImportAllTest.php
ContentEntity.php in core/modules/migrate_drupal/src/Plugin/migrate/source/ContentEntity.php
ContentEntityDeriver.php in core/modules/migrate_drupal/src/Plugin/migrate/source/ContentEntityDeriver.php
ContentLanguageSettingsForm.php in core/modules/language/src/Form/ContentLanguageSettingsForm.php
ContentModerationStateStorageSchema.php in core/modules/content_moderation/src/ContentModerationStateStorageSchema.php
content_translation.admin.inc in core/modules/content_translation/content_translation.admin.inc
The content translation administration forms.
DefaultTableMapping.php in core/lib/Drupal/Core/Entity/Sql/DefaultTableMapping.php
EntityConverterTest.php in core/tests/Drupal/Tests/Core/ParamConverter/EntityConverterTest.php
EntityFieldManagerTest.php in core/tests/Drupal/Tests/Core/Entity/EntityFieldManagerTest.php
EntitySchemaTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntitySchemaTest.php
EntityTestUpdateStorageSchema.php in core/modules/system/tests/modules/entity_test_update/src/EntityTestUpdateStorageSchema.php
EntityTypeInfo.php in core/modules/content_moderation/src/EntityTypeInfo.php
entity_schema_test.module in core/modules/system/tests/modules/entity_schema_test/entity_schema_test.module
Test module for the entity API providing a bundle field.
FieldDefinitionIntegrityTest.php in core/modules/field/tests/src/Kernel/FieldDefinitionIntegrityTest.php
ModuleHandlerTest.php in core/modules/system/tests/src/Kernel/Extension/ModuleHandlerTest.php
NodeStorageSchema.php in core/modules/node/src/NodeStorageSchema.php
PathAliasStorageSchema.php in core/modules/path_alias/src/PathAliasStorageSchema.php
ResourceTestBase.php in core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php
ResourceTypeRepository.php in core/modules/jsonapi/src/ResourceType/ResourceTypeRepository.php
SqlContentEntityStorage.php in core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
SqlContentEntityStorageSchema.php in core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorageSchema.php
SqlContentEntityStorageSchemaTest.php in core/tests/Drupal/Tests/Core/Entity/Sql/SqlContentEntityStorageSchemaTest.php
system.module in core/modules/system/system.module
Configuration system that lets administrators modify the workings of the site.
TermStorageSchema.php in core/modules/taxonomy/src/TermStorageSchema.php
UserStorageSchema.php in core/modules/user/src/UserStorageSchema.php
views.views.inc in core/modules/views/views.views.inc
Provide views data that isn't tied to any other module.
ViewsConfigDependenciesIntegrationTest.php in core/modules/views/tests/src/Kernel/ViewsConfigDependenciesIntegrationTest.php
ViewsEntitySchemaSubscriberIntegrationTest.php in core/modules/views/tests/src/Kernel/EventSubscriber/ViewsEntitySchemaSubscriberIntegrationTest.php

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