13 files declare their use of ContactForm

ConfigTranslationListUiTest.php in core/modules/config_translation/tests/src/Functional/ConfigTranslationListUiTest.php
contact.post_update.php in core/modules/contact/contact.post_update.php
Post update functions for Contact.
ContactFieldsTest.php in core/modules/contact/tests/src/Kernel/Views/ContactFieldsTest.php
ContactFormResourceTestBase.php in core/modules/contact/tests/src/Functional/Rest/ContactFormResourceTestBase.php
ContactFormTest.php in core/modules/jsonapi/tests/src/Functional/ContactFormTest.php
ContactSitewideTest.php in core/modules/contact/tests/src/Functional/ContactSitewideTest.php
ContentEntityNullStorageTest.php in core/tests/Drupal/KernelTests/Core/Entity/ContentEntityNullStorageTest.php
demo_umami.profile in core/profiles/demo_umami/demo_umami.profile
Enables modules and site configuration for a demo_umami site installation.
MessageResourceTestBase.php in core/modules/contact/tests/src/Functional/Rest/MessageResourceTestBase.php
MessageTest.php in core/modules/jsonapi/tests/src/Functional/MessageTest.php
MigrateContactCategoryTest.php in core/modules/contact/tests/src/Kernel/Migrate/MigrateContactCategoryTest.php
standard.profile in core/profiles/standard/standard.profile
Enables modules and site configuration for a standard site installation.
StandardTest.php in core/profiles/standard/tests/src/Functional/StandardTest.php

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