25 files declare their use of CacheableResponseInterface

AnonymousUserResponseSubscriber.php in core/lib/Drupal/Core/EventSubscriber/AnonymousUserResponseSubscriber.php
CacheableResourceResponse.php in core/modules/jsonapi/src/CacheableResourceResponse.php
CacheableSecuredRedirectResponse.php in core/lib/Drupal/Core/Routing/CacheableSecuredRedirectResponse.php
CacheableTestResponse.php in core/modules/system/tests/modules/early_rendering_controller_test/src/CacheableTestResponse.php
ClientErrorResponseSubscriber.php in core/lib/Drupal/Core/EventSubscriber/ClientErrorResponseSubscriber.php
CommentController.php in core/modules/comment/src/Controller/CommentController.php
DefaultExceptionHtmlSubscriber.php in core/lib/Drupal/Core/EventSubscriber/DefaultExceptionHtmlSubscriber.php
DynamicPageCacheSubscriber.php in core/modules/dynamic_page_cache/src/EventSubscriber/DynamicPageCacheSubscriber.php
EarlyRenderingControllerWrapperSubscriber.php in core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php
EntityResource.php in core/modules/rest/src/Plugin/rest/resource/EntityResource.php
EntityResource.php in core/modules/jsonapi/src/Controller/EntityResource.php
EntityResourceTestBase.php in core/modules/rest/tests/src/Functional/EntityResource/EntityResourceTestBase.php
FinishResponseSubscriber.php in core/lib/Drupal/Core/EventSubscriber/FinishResponseSubscriber.php
HtmlResponse.php in core/lib/Drupal/Core/Render/HtmlResponse.php
JsonApiRequestValidator.php in core/modules/jsonapi/src/EventSubscriber/JsonApiRequestValidator.php
MainContentViewSubscriber.php in core/lib/Drupal/Core/EventSubscriber/MainContentViewSubscriber.php
PageCache.php in core/modules/page_cache/src/StackMiddleware/PageCache.php
RequestHandler.php in core/modules/rest/src/RequestHandler.php
ResourceResponse.php in core/modules/rest/src/ResourceResponse.php
ResourceResponseSubscriber.php in core/modules/jsonapi/src/EventSubscriber/ResourceResponseSubscriber.php
ResourceResponseSubscriber.php in core/modules/rest/src/EventSubscriber/ResourceResponseSubscriber.php
ResourceResponseSubscriberTest.php in core/modules/rest/tests/src/Unit/EventSubscriber/ResourceResponseSubscriberTest.php
ResourceTestBase.php in core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php
RouteAccessResponseSubscriber.php in core/lib/Drupal/Core/EventSubscriber/RouteAccessResponseSubscriber.php
TrustedRedirectResponseTest.php in core/tests/Drupal/Tests/Core/Routing/TrustedRedirectResponseTest.php

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