44 files declare their use of ThemeManagerInterface

AssetControllerBase.php in core/modules/system/src/Controller/AssetControllerBase.php
AssetResolver.php in core/lib/Drupal/Core/Asset/AssetResolver.php
AssetResolverTest.php in core/tests/Drupal/Tests/Core/Asset/AssetResolverTest.php
BatchInjectionCallbacks.php in core/modules/system/tests/modules/batch_test/src/BatchInjectionCallbacks.php
BlockController.php in core/modules/block/src/Controller/BlockController.php
BlockFormTest.php in core/modules/block/tests/src/Unit/BlockFormTest.php
BlockListBuilder.php in core/modules/block/src/BlockListBuilder.php
BlockRepository.php in core/modules/block/src/BlockRepository.php
BubbleableMetadataTest.php in core/tests/Drupal/Tests/Core/Render/BubbleableMetadataTest.php
CssCollectionOptimizerLazy.php in core/lib/Drupal/Core/Asset/CssCollectionOptimizerLazy.php
CssCollectionOptimizerLazyUnitTest.php in core/tests/Drupal/Tests/Core/Asset/CssCollectionOptimizerLazyUnitTest.php
CurrentThemeCondition.php in core/modules/system/src/Plugin/Condition/CurrentThemeCondition.php
ElementInfoManager.php in core/lib/Drupal/Core/Render/ElementInfoManager.php
ElementInfoManagerTest.php in core/tests/Drupal/Tests/Core/Render/ElementInfoManagerTest.php
FiberPlaceholderTest.php in core/modules/big_pipe/tests/src/Unit/Render/FiberPlaceholderTest.php
FilteredPluginManagerTrait.php in core/lib/Drupal/Core/Plugin/FilteredPluginManagerTrait.php
FilteredPluginManagerTraitTest.php in core/tests/Drupal/Tests/Core/Plugin/FilteredPluginManagerTraitTest.php
FormBuilder.php in core/lib/Drupal/Core/Form/FormBuilder.php
FormTestBase.php in core/tests/Drupal/Tests/Core/Form/FormTestBase.php
HtmlRenderer.php in core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
JsCollectionOptimizerLazy.php in core/lib/Drupal/Core/Asset/JsCollectionOptimizerLazy.php
LayoutPluginManagerTest.php in core/tests/Drupal/Tests/Core/Layout/LayoutPluginManagerTest.php
LibraryDiscoveryCollector.php in core/lib/Drupal/Core/Asset/LibraryDiscoveryCollector.php
LibraryDiscoveryCollectorTest.php in core/tests/Drupal/Tests/Core/Asset/LibraryDiscoveryCollectorTest.php
LibraryDiscoveryParser.php in core/lib/Drupal/Core/Asset/LibraryDiscoveryParser.php
LibraryDiscoveryParserTest.php in core/tests/Drupal/Tests/Core/Asset/LibraryDiscoveryParserTest.php
MenuTestController.php in core/modules/system/tests/modules/menu_test/src/Controller/MenuTestController.php
PreprocessHooks.php in core/themes/default_admin/src/Hook/PreprocessHooks.php
PreprocessHooks.php in core/themes/admin/src/Hook/PreprocessHooks.php
RegistryTest.php in core/tests/Drupal/Tests/Core/Theme/RegistryTest.php
Renderer.php in core/lib/Drupal/Core/Render/Renderer.php
RendererTest.php in core/tests/Drupal/Tests/Core/Render/RendererTest.php
RendererTestBase.php in core/tests/Drupal/Tests/Core/Render/RendererTestBase.php
SettingsForm.php in core/modules/navigation/src/Form/SettingsForm.php
SystemController.php in core/modules/system/src/Controller/SystemController.php
ThemeCacheContext.php in core/lib/Drupal/Core/Cache/Context/ThemeCacheContext.php
ThemeSettingsForm.php in core/modules/system/src/Form/ThemeSettingsForm.php
ThemeSettingsProvider.php in core/lib/Drupal/Core/Extension/ThemeSettingsProvider.php
ToolbarClaroOverridesTest.php in core/modules/system/tests/src/Functional/Theme/ToolbarClaroOverridesTest.php
ToolbarThemeHooks.php in core/modules/toolbar/src/Hook/ToolbarThemeHooks.php
TwigExtension.php in core/lib/Drupal/Core/Template/TwigExtension.php
TwigExtensionTest.php in core/tests/Drupal/Tests/Core/Template/TwigExtensionTest.php
ViewAjaxControllerTest.php in core/modules/views/tests/src/Unit/Controller/ViewAjaxControllerTest.php
ViewEditForm.php in core/modules/views_ui/src/ViewEditForm.php

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