28 files declare their use of BubbleableMetadata

Actions.php in core/lib/Drupal/Core/Render/Element/Actions.php
AjaxResponse.php in core/lib/Drupal/Core/Ajax/AjaxResponse.php
ComponentRenderTest.php in core/tests/Drupal/KernelTests/Components/ComponentRenderTest.php
EarlyRenderingControllerWrapperSubscriber.php in core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php
FormElementBase.php in core/lib/Drupal/Core/Render/Element/FormElementBase.php
GeneratedLink.php in core/lib/Drupal/Core/GeneratedLink.php
GeneratedUrl.php in core/lib/Drupal/Core/GeneratedUrl.php
HelpTwigExtension.php in core/modules/help/src/HelpTwigExtension.php
LanguageNegotiationContentEntityTest.php in core/modules/language/tests/src/Unit/Plugin/LanguageNegotiation/LanguageNegotiationContentEntityTest.php
Link.php in core/lib/Drupal/Core/Render/Element/Link.php
NullGenerator.php in core/lib/Drupal/Core/Routing/NullGenerator.php
NullPathProcessorManager.php in core/lib/Drupal/Core/PathProcessor/NullPathProcessorManager.php
OutboundPathProcessorInterface.php in core/lib/Drupal/Core/PathProcessor/OutboundPathProcessorInterface.php
OutboundRouteProcessorInterface.php in core/lib/Drupal/Core/RouteProcessor/OutboundRouteProcessorInterface.php
PathProcessorManager.php in core/lib/Drupal/Core/PathProcessor/PathProcessorManager.php
RenderElementBase.php in core/lib/Drupal/Core/Render/Element/RenderElementBase.php
RouteProcessorCsrf.php in core/lib/Drupal/Core/Access/RouteProcessorCsrf.php
RouteProcessorCsrfTest.php in core/tests/Drupal/Tests/Core/Access/RouteProcessorCsrfTest.php
RouteProcessorCurrent.php in core/lib/Drupal/Core/RouteProcessor/RouteProcessorCurrent.php
RouteProcessorManager.php in core/lib/Drupal/Core/RouteProcessor/RouteProcessorManager.php
RouteProcessorManagerTest.php in core/tests/Drupal/Tests/Core/RouteProcessor/RouteProcessorManagerTest.php
theme.inc in core/includes/theme.inc
The theme system, which controls the output of Drupal.
Token.php in core/lib/Drupal/Core/Utility/Token.php
TokenReplaceTest.php in core/modules/taxonomy/tests/src/Kernel/TokenReplaceTest.php
TokenTest.php in core/tests/Drupal/Tests/Core/Utility/TokenTest.php
TwigExtension.php in core/lib/Drupal/Core/Template/TwigExtension.php
UnroutedUrlAssemblerTest.php in core/tests/Drupal/Tests/Core/Utility/UnroutedUrlAssemblerTest.php
UrlGenerator.php in core/lib/Drupal/Core/Routing/UrlGenerator.php

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