44 files declare their use of PluginInspectionInterface

ActionInterface.php in core/lib/Drupal/Core/Action/ActionInterface.php
BlockPluginInterface.php in core/lib/Drupal/Core/Block/BlockPluginInterface.php
CKEditorPluginInterface.php in core/modules/ckeditor/src/CKEditorPluginInterface.php
ConditionInterface.php in core/lib/Drupal/Core/Condition/ConditionInterface.php
DefaultLazyPluginCollectionTest.php in core/tests/Drupal/Tests/Core/Plugin/DefaultLazyPluginCollectionTest.php
EditorPluginInterface.php in core/modules/editor/src/Plugin/EditorPluginInterface.php
ElementInterface.php in core/lib/Drupal/Core/Render/Element/ElementInterface.php
FilterFormat.php in core/modules/filter/src/Entity/FilterFormat.php
FilterInterface.php in core/modules/filter/src/Plugin/FilterInterface.php
HelpSectionPluginInterface.php in core/modules/help/src/HelpSectionPluginInterface.php
HelpTopicPluginInterface.php in core/modules/help_topics/src/HelpTopicPluginInterface.php
ImageEffectInterface.php in core/modules/image/src/ImageEffectInterface.php
ImageToolkitInterface.php in core/lib/Drupal/Core/ImageToolkit/ImageToolkitInterface.php
ImageToolkitOperationInterface.php in core/lib/Drupal/Core/ImageToolkit/ImageToolkitOperationInterface.php
InPlaceEditorInterface.php in core/modules/quickedit/src/Plugin/InPlaceEditorInterface.php
LayoutEntityHelperTraitTest.php in core/modules/layout_builder/tests/src/Unit/LayoutEntityHelperTraitTest.php
LayoutInterface.php in core/lib/Drupal/Core/Layout/LayoutInterface.php
MediaSourceInterface.php in core/modules/media/src/MediaSourceInterface.php
MenuLinkInterface.php in core/lib/Drupal/Core/Menu/MenuLinkInterface.php
MenuLinkParentTest.php in core/modules/migrate/tests/src/Unit/process/MenuLinkParentTest.php
MigrateDestinationInterface.php in core/modules/migrate/src/Plugin/MigrateDestinationInterface.php
MigrateFieldInterface.php in core/modules/migrate_drupal/src/Plugin/MigrateFieldInterface.php
MigrateIdMapInterface.php in core/modules/migrate/src/Plugin/MigrateIdMapInterface.php
MigrateProcessInterface.php in core/modules/migrate/src/Plugin/MigrateProcessInterface.php
MigrateSourceInterface.php in core/modules/migrate/src/Plugin/MigrateSourceInterface.php
MigrationInterface.php in core/modules/migrate/src/Plugin/MigrationInterface.php
PluginDependencyTrait.php in core/lib/Drupal/Core/Plugin/PluginDependencyTrait.php
PluginDependencyTraitTest.php in core/tests/Drupal/Tests/Core/Plugin/PluginDependencyTraitTest.php
PluginFormBase.php in core/lib/Drupal/Core/Plugin/PluginFormBase.php
PluginInterface.php in core/modules/views/src/Plugin/views/PluginInterface.php
PluginSettingsInterface.php in core/lib/Drupal/Core/Field/PluginSettingsInterface.php
PluginWithFormsInterface.php in core/lib/Drupal/Core/Plugin/PluginWithFormsInterface.php
QueueWorkerInterface.php in core/lib/Drupal/Core/Queue/QueueWorkerInterface.php
ResourceInterface.php in core/modules/rest/src/Plugin/ResourceInterface.php
SearchInterface.php in core/modules/search/src/Plugin/SearchInterface.php
SectionStorageInterface.php in core/modules/layout_builder/src/SectionStorageInterface.php
SerializedColumnNormalizerTrait.php in core/modules/serialization/src/Normalizer/SerializedColumnNormalizerTrait.php
SystemMenuOffCanvasForm.php in core/modules/system/src/Form/SystemMenuOffCanvasForm.php
TypedData.php in core/lib/Drupal/Core/TypedData/TypedData.php
VariantInterface.php in core/lib/Drupal/Core/Display/VariantInterface.php
ViewsPluginInterface.php in core/modules/views/src/Plugin/views/ViewsPluginInterface.php
WorkflowTypeConfigureFormBase.php in core/modules/workflows/src/Plugin/WorkflowTypeConfigureFormBase.php
WorkflowTypeStateFormBase.php in core/modules/workflows/src/Plugin/WorkflowTypeStateFormBase.php
WorkflowTypeTransitionFormBase.php in core/modules/workflows/src/Plugin/WorkflowTypeTransitionFormBase.php

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