43 files declare their use of RenderContext

AssertContentTrait.php in core/tests/Drupal/KernelTests/AssertContentTrait.php
CacheTest.php in core/modules/views/tests/src/Kernel/Plugin/CacheTest.php
CommentFieldNameTest.php in core/modules/comment/tests/src/Kernel/Views/CommentFieldNameTest.php
ComponentKernelTestBase.php in core/tests/Drupal/Tests/Core/Theme/Component/ComponentKernelTestBase.php
ComponentRendererTrait.php in core/modules/sdc/tests/src/Traits/ComponentRendererTrait.php
EarlyRenderingControllerWrapperSubscriber.php in core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php
EntityResource.php in core/modules/jsonapi/src/Controller/EntityResource.php
ExtensionViewsFieldTest.php in core/modules/file/tests/src/Kernel/Views/ExtensionViewsFieldTest.php
FieldDropbuttonTest.php in core/modules/views/tests/src/Kernel/Handler/FieldDropbuttonTest.php
FieldGroupRowsTest.php in core/modules/views/tests/src/Kernel/Handler/FieldGroupRowsTest.php
FieldKernelTest.php in core/modules/views/tests/src/Kernel/Handler/FieldKernelTest.php
FieldSelfTokensTest.php in core/modules/views/tests/src/Kernel/Handler/FieldSelfTokensTest.php
FieldWebTest.php in core/modules/views/tests/src/Functional/Handler/FieldWebTest.php
FilterCaptionTwigDebugTest.php in core/modules/filter/tests/src/Kernel/FilterCaptionTwigDebugTest.php
FilterKernelTest.php in core/modules/filter/tests/src/Kernel/FilterKernelTest.php
HandlerFieldUserNameTest.php in core/modules/user/tests/src/Functional/Views/HandlerFieldUserNameTest.php
HelpTopicSection.php in core/modules/help/src/Plugin/HelpSection/HelpTopicSection.php
HtmlRenderer.php in core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
IconBuilderTest.php in core/tests/Drupal/KernelTests/Core/Layout/IconBuilderTest.php
LinkGenerationTest.php in core/tests/Drupal/KernelTests/Core/Url/LinkGenerationTest.php
MailManager.php in core/lib/Drupal/Core/Mail/MailManager.php
MailManagerTest.php in core/tests/Drupal/Tests/Core/Mail/MailManagerTest.php
MediaEmbed.php in core/modules/media/src/Plugin/Filter/MediaEmbed.php
MediaEmbedFilterTestBase.php in core/modules/media/tests/src/Kernel/MediaEmbedFilterTestBase.php
OEmbedIframeController.php in core/modules/media/src/Controller/OEmbedIframeController.php
OEmbedSourceTest.php in core/modules/media/tests/src/Kernel/OEmbedSourceTest.php
PluginBaseTest.php in core/modules/views/tests/src/Kernel/Plugin/PluginBaseTest.php
RendererPlaceholdersTest.php in core/tests/Drupal/Tests/Core/Render/RendererPlaceholdersTest.php
RenderPlaceholderMessageTestController.php in core/modules/system/tests/modules/render_placeholder_message_test/src/RenderPlaceholderMessageTestController.php
ResourceResponseSubscriberTest.php in core/modules/rest/tests/src/Unit/EventSubscriber/ResourceResponseSubscriberTest.php
RestExport.php in core/modules/rest/src/Plugin/views/display/RestExport.php
StateFormatterTest.php in core/modules/content_moderation/tests/src/Kernel/StateFormatterTest.php
TaxonomyFieldTidTest.php in core/modules/taxonomy/tests/src/Kernel/Views/TaxonomyFieldTidTest.php
TaxonomyFieldVidTest.php in core/modules/taxonomy/tests/src/Kernel/Views/TaxonomyFieldVidTest.php
ThemeRenderAndAutoescapeTest.php in core/tests/Drupal/KernelTests/Core/Theme/ThemeRenderAndAutoescapeTest.php
toolbar.module in core/modules/toolbar/toolbar.module
Administration toolbar for quick access to top level administration items.
ToolbarController.php in core/modules/toolbar/src/Controller/ToolbarController.php
TwigMarkupInterfaceTest.php in core/tests/Drupal/KernelTests/Core/Theme/TwigMarkupInterfaceTest.php
UnpublishByKeywordActionTest.php in core/modules/node/tests/src/Kernel/Action/UnpublishByKeywordActionTest.php
UrlTest.php in core/modules/system/tests/src/Kernel/Common/UrlTest.php
ViewAjaxControllerTest.php in core/modules/views/tests/src/Unit/Controller/ViewAjaxControllerTest.php
ViewsFormBase.php in core/modules/views_ui/src/Form/Ajax/ViewsFormBase.php
ViewsHooksTest.php in core/modules/views/tests/src/Kernel/ViewsHooksTest.php

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