44 files declare their use of CacheableMetadata

AccountPermissionsCacheContext.php in core/lib/Drupal/Core/Cache/Context/AccountPermissionsCacheContext.php
AnonymousUserResponseSubscriber.php in core/lib/Drupal/Core/EventSubscriber/AnonymousUserResponseSubscriber.php
BubbleableMetadata.php in core/lib/Drupal/Core/Render/BubbleableMetadata.php
CacheContextsManager.php in core/lib/Drupal/Core/Cache/Context/CacheContextsManager.php
ClientErrorResponseSubscriber.php in core/lib/Drupal/Core/EventSubscriber/ClientErrorResponseSubscriber.php
ConfigEntityStorage.php in core/lib/Drupal/Core/Config/Entity/ConfigEntityStorage.php
ConfigOverride.php in core/lib/Drupal/Core/Installer/ConfigOverride.php
Context.php in core/lib/Drupal/Core/Plugin/Context/Context.php
ContextCacheKeys.php in core/lib/Drupal/Core/Cache/Context/ContextCacheKeys.php
CookiesCacheContext.php in core/lib/Drupal/Core/Cache/Context/CookiesCacheContext.php
CurrentLanguageContext.php in core/lib/Drupal/Core/Language/ContextProvider/CurrentLanguageContext.php
EntityReferenceFormatterBase.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/EntityReferenceFormatterBase.php
Fast404ExceptionHtmlSubscriber.php in core/lib/Drupal/Core/EventSubscriber/Fast404ExceptionHtmlSubscriber.php
HeadersCacheContext.php in core/lib/Drupal/Core/Cache/Context/HeadersCacheContext.php
HtmlResponse.php in core/lib/Drupal/Core/Render/HtmlResponse.php
IpCacheContext.php in core/lib/Drupal/Core/Cache/Context/IpCacheContext.php
IsFrontPathCacheContext.php in core/lib/Drupal/Core/Cache/Context/IsFrontPathCacheContext.php
IsSuperUserCacheContext.php in core/lib/Drupal/Core/Cache/Context/IsSuperUserCacheContext.php
LanguagesCacheContext.php in core/lib/Drupal/Core/Cache/Context/LanguagesCacheContext.php
LocalActionManager.php in core/lib/Drupal/Core/Menu/LocalActionManager.php
LocalTaskManager.php in core/lib/Drupal/Core/Menu/LocalTaskManager.php
LocalTasksBlock.php in core/lib/Drupal/Core/Menu/Plugin/Block/LocalTasksBlock.php
MainContentViewSubscriber.php in core/lib/Drupal/Core/EventSubscriber/MainContentViewSubscriber.php
MenuActiveTrailsCacheContext.php in core/lib/Drupal/Core/Cache/Context/MenuActiveTrailsCacheContext.php
MenuLinkTree.php in core/lib/Drupal/Core/Menu/MenuLinkTree.php
MenuParentFormSelector.php in core/lib/Drupal/Core/Menu/MenuParentFormSelector.php
MenuParentFormSelectorInterface.php in core/lib/Drupal/Core/Menu/MenuParentFormSelectorInterface.php
PagersCacheContext.php in core/lib/Drupal/Core/Cache/Context/PagersCacheContext.php
PathCacheContext.php in core/lib/Drupal/Core/Cache/Context/PathCacheContext.php
PathParentCacheContext.php in core/lib/Drupal/Core/Cache/Context/PathParentCacheContext.php
ProtocolVersionCacheContext.php in core/lib/Drupal/Core/Cache/Context/ProtocolVersionCacheContext.php
QueryArgsCacheContext.php in core/lib/Drupal/Core/Cache/Context/QueryArgsCacheContext.php
RenderCache.php in core/lib/Drupal/Core/Render/RenderCache.php
Renderer.php in core/lib/Drupal/Core/Render/Renderer.php
RequestFormatCacheContext.php in core/lib/Drupal/Core/Cache/Context/RequestFormatCacheContext.php
RouteCacheContext.php in core/lib/Drupal/Core/Cache/Context/RouteCacheContext.php
SessionExistsCacheContext.php in core/lib/Drupal/Core/Cache/Context/SessionExistsCacheContext.php
SiteCacheContext.php in core/lib/Drupal/Core/Cache/Context/SiteCacheContext.php
ThemeCacheContext.php in core/lib/Drupal/Core/Cache/Context/ThemeCacheContext.php
TimestampAgoFormatter.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/TimestampAgoFormatter.php
TimeZoneCacheContext.php in core/lib/Drupal/Core/Cache/Context/TimeZoneCacheContext.php
UrlCacheContext.php in core/lib/Drupal/Core/Cache/Context/UrlCacheContext.php
UserCacheContext.php in core/lib/Drupal/Core/Cache/Context/UserCacheContext.php
UserRolesCacheContext.php in core/lib/Drupal/Core/Cache/Context/UserRolesCacheContext.php

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