42 files declare their use of PluginManagerInterface

BlockPluginCollection.php in core/modules/block/src/BlockPluginCollection.php
ConfigEntityBaseUnitTest.php in core/tests/Drupal/Tests/Core/Config/Entity/ConfigEntityBaseUnitTest.php
Contains \Drupal\Tests\Core\Config\Entity\ConfigEntityBaseUnitTest.
ConfigMapperManagerInterface.php in core/modules/config_translation/src/ConfigMapperManagerInterface.php
ContextAwarePluginManagerInterface.php in core/lib/Drupal/Core/Plugin/Context/ContextAwarePluginManagerInterface.php
D6TermNodeDeriver.php in core/modules/taxonomy/src/Plugin/migrate/D6TermNodeDeriver.php
DefaultLazyPluginCollection.php in core/lib/Drupal/Core/Plugin/DefaultLazyPluginCollection.php
DefaultLazyPluginCollectionTest.php in core/tests/Drupal/Tests/Core/Plugin/DefaultLazyPluginCollectionTest.php
DefaultPluginManager.php in core/lib/Drupal/Core/Plugin/DefaultPluginManager.php
DefaultSingleLazyPluginCollection.php in core/lib/Drupal/Core/Plugin/DefaultSingleLazyPluginCollection.php
DisplayPluginCollection.php in core/modules/views/src/DisplayPluginCollection.php
EditorSelector.php in core/modules/quickedit/src/EditorSelector.php
Element.php in core/modules/editor/src/Element.php
EntityFormDisplayAccessControlHandlerTest.php in core/tests/Drupal/Tests/Core/Entity/Access/EntityFormDisplayAccessControlHandlerTest.php
EntityResource.php in core/modules/rest/src/Plugin/rest/resource/EntityResource.php
EntityTypeManagerInterface.php in core/lib/Drupal/Core/Entity/EntityTypeManagerInterface.php
ExecutableManagerInterface.php in core/lib/Drupal/Core/Executable/ExecutableManagerInterface.php
FieldTypePluginManagerInterface.php in core/lib/Drupal/Core/Field/FieldTypePluginManagerInterface.php
FilteredPluginManagerInterface.php in core/lib/Drupal/Core/Plugin/FilteredPluginManagerInterface.php
FilterID.php in core/modules/filter/src/Plugin/migrate/process/FilterID.php
FilterUninstallValidator.php in core/modules/filter/src/FilterUninstallValidator.php
HelpSectionManager.php in core/modules/help_topics/src/HelpSectionManager.php
HelpTopicPluginManagerInterface.php in core/modules/help_topics/src/HelpTopicPluginManagerInterface.php
HtmlRenderer.php in core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
LanguageNegotiator.php in core/modules/language/src/LanguageNegotiator.php
LocalActionManagerInterface.php in core/lib/Drupal/Core/Menu/LocalActionManagerInterface.php
LocalTaskManagerInterface.php in core/lib/Drupal/Core/Menu/LocalTaskManagerInterface.php
MailManagerInterface.php in core/lib/Drupal/Core/Mail/MailManagerInterface.php
MediaTypeForm.php in core/modules/media/src/MediaTypeForm.php
MenuLinkManagerInterface.php in core/lib/Drupal/Core/Menu/MenuLinkManagerInterface.php
MetadataGenerator.php in core/modules/quickedit/src/MetadataGenerator.php
MigratePluginManagerInterface.php in core/modules/migrate/src/Plugin/MigratePluginManagerInterface.php
MigrationPluginManagerInterface.php in core/modules/migrate/src/Plugin/MigrationPluginManagerInterface.php
QueueWorkerManagerInterface.php in core/lib/Drupal/Core/Queue/QueueWorkerManagerInterface.php
SearchPluginCollection.php in core/modules/search/src/Plugin/SearchPluginCollection.php
SelectionPluginManagerInterface.php in core/lib/Drupal/Core/Entity/EntityReferenceSelection/SelectionPluginManagerInterface.php
TestLazyPluginCollection.php in core/modules/system/tests/modules/plugin_test/src/Plugin/TestLazyPluginCollection.php
TypedDataManagerInterface.php in core/lib/Drupal/Core/TypedData/TypedDataManagerInterface.php
ViewExecutableTest.php in core/modules/views/tests/src/Unit/ViewExecutableTest.php
ViewListBuilder.php in core/modules/views_ui/src/ViewListBuilder.php
WorkflowAccessControlHandler.php in core/modules/workflows/src/WorkflowAccessControlHandler.php
WorkflowAddForm.php in core/modules/workflows/src/Form/WorkflowAddForm.php
WorkflowListBuilder.php in core/modules/workflows/src/WorkflowListBuilder.php

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