6 files declare their use of ContextAwarePluginDefinitionInterface

ContextAwarePluginTrait.php in core/lib/Drupal/Core/Plugin/ContextAwarePluginTrait.php
ContextAwarePluginTraitTest.php in core/tests/Drupal/KernelTests/Core/Plugin/Context/ContextAwarePluginTraitTest.php
ContextHandler.php in core/lib/Drupal/Core/Plugin/Context/ContextHandler.php
ContextHandlerTest.php in core/tests/Drupal/Tests/Core/Plugin/ContextHandlerTest.php
LayoutDefinition.php in core/lib/Drupal/Core/Layout/LayoutDefinition.php
SectionStorageDefinition.php in core/modules/layout_builder/src/SectionStorage/SectionStorageDefinition.php

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