32 files declare their use of ContentLanguageSettings in Drupal 9

BlockContentTypeForm.php in core/modules/block_content/src/BlockContentTypeForm.php

CKEditorIntegrationTest.php in core/modules/media/tests/src/FunctionalJavascript/CKEditorIntegrationTest.php

CommentTypeForm.php in core/modules/comment/src/CommentTypeForm.php

ConfigurableLanguageManagerTest.php in core/modules/language/tests/src/Functional/ConfigurableLanguageManagerTest.php

ContentLanguageSettingsForm.php in core/modules/language/src/Form/ContentLanguageSettingsForm.php

ContentLanguageSettingsResourceTestBase.php in core/modules/language/tests/src/Functional/Rest/ContentLanguageSettingsResourceTestBase.php

ContentLanguageSettingsTest.php in core/modules/jsonapi/tests/src/Functional/ContentLanguageSettingsTest.php

ContentLanguageSettingsUnitTest.php in core/modules/language/tests/src/Unit/ContentLanguageSettingsUnitTest.php

ContentTranslationDeleteAccess.php in core/modules/content_translation/src/Access/ContentTranslationDeleteAccess.php

ContentTranslationSettingsTest.php in core/modules/content_translation/tests/src/Functional/ContentTranslationSettingsTest.php

entity.api.php in core/lib/Drupal/Core/Entity/entity.api.php

Hooks and documentation related to entities.

EntityDefaultLanguageTest.php in core/modules/language/tests/src/Kernel/EntityDefaultLanguageTest.php

FieldApiDataTest.php in core/modules/views/tests/src/Kernel/FieldApiDataTest.php

JsonApiFunctionalMultilingualTest.php in core/modules/jsonapi/tests/src/Functional/JsonApiFunctionalMultilingualTest.php

language.module in core/modules/language/language.module

Add language handling functionality to Drupal.

LanguageConfigurationElement.php in core/modules/language/tests/language_elements_test/src/Form/LanguageConfigurationElement.php

LanguageConfigurationElementTest.php in core/modules/language/tests/src/Functional/LanguageConfigurationElementTest.php

MediaTypeForm.php in core/modules/media/src/MediaTypeForm.php

MenuUiLanguageTest.php in core/modules/menu_ui/tests/src/Functional/MenuUiLanguageTest.php

MigrateLanguageContentCommentSettingsNoEntityTranslationTest.php in core/modules/language/tests/src/Kernel/Migrate/d7/MigrateLanguageContentCommentSettingsNoEntityTranslationTest.php

MigrateLanguageContentCommentSettingsTest.php in core/modules/language/tests/src/Kernel/Migrate/d6/MigrateLanguageContentCommentSettingsTest.php

MigrateLanguageContentCommentSettingsTest.php in core/modules/language/tests/src/Kernel/Migrate/d7/MigrateLanguageContentCommentSettingsTest.php

MigrateLanguageContentMenuSettingsTest.php in core/modules/language/tests/src/Kernel/Migrate/d6/MigrateLanguageContentMenuSettingsTest.php

MigrateLanguageContentMenuSettingsTest.php in core/modules/language/tests/src/Kernel/Migrate/d7/MigrateLanguageContentMenuSettingsTest.php

MigrateLanguageContentSettingsTest.php in core/modules/language/tests/src/Kernel/Migrate/d6/MigrateLanguageContentSettingsTest.php

MigrateLanguageContentSettingsTest.php in core/modules/language/tests/src/Kernel/Migrate/d7/MigrateLanguageContentSettingsTest.php

MigrateLanguageContentTaxonomyVocabularySettingsTest.php in core/modules/language/tests/src/Kernel/Migrate/d6/MigrateLanguageContentTaxonomyVocabularySettingsTest.php

MigrateLanguageContentTaxonomyVocabularySettingsTest.php in core/modules/language/tests/src/Kernel/Migrate/d7/MigrateLanguageContentTaxonomyVocabularySettingsTest.php

NodeTypeForm.php in core/modules/node/src/NodeTypeForm.php

UsageTest.php in core/modules/file/tests/src/Kernel/UsageTest.php

VocabularyForm.php in core/modules/taxonomy/src/VocabularyForm.php

VocabularyLanguageTest.php in core/modules/taxonomy/tests/src/Functional/VocabularyLanguageTest.php