18 files declare their use of CacheableNormalization

DataNormalizer.php in core/modules/jsonapi/src/Normalizer/DataNormalizer.php
EntityReferenceFieldNormalizer.php in core/modules/jsonapi/src/Normalizer/EntityReferenceFieldNormalizer.php
FieldItemNormalizer.php in core/modules/jsonapi/src/Normalizer/FieldItemNormalizer.php
FieldItemNormalizerTest.php in core/modules/jsonapi/tests/src/Kernel/Normalizer/FieldItemNormalizerTest.php
FieldNormalizer.php in core/modules/jsonapi/src/Normalizer/FieldNormalizer.php
JsonApiDocumentTopLevelNormalizer.php in core/modules/jsonapi/src/Normalizer/JsonApiDocumentTopLevelNormalizer.php
LinkCollectionNormalizer.php in core/modules/jsonapi/src/Normalizer/LinkCollectionNormalizer.php
LinkCollectionNormalizerTest.php in core/modules/jsonapi/tests/src/Kernel/Normalizer/LinkCollectionNormalizerTest.php
NodeTest.php in core/modules/jsonapi/tests/src/Functional/NodeTest.php
NormalizerBase.php in core/modules/jsonapi/src/Normalizer/NormalizerBase.php
RelationshipNormalizer.php in core/modules/jsonapi/src/Normalizer/RelationshipNormalizer.php
RelationshipNormalizerTest.php in core/modules/jsonapi/tests/src/Kernel/Normalizer/RelationshipNormalizerTest.php
ResourceIdentifierNormalizer.php in core/modules/jsonapi/src/Normalizer/ResourceIdentifierNormalizer.php
ResourceObjectNormalizationCacher.php in core/modules/jsonapi/src/EventSubscriber/ResourceObjectNormalizationCacher.php
ResourceObjectNormalizer.php in core/modules/jsonapi/src/Normalizer/ResourceObjectNormalizer.php
ResourceObjectNormalizerCacherTest.php in core/modules/jsonapi/tests/src/Kernel/EventSubscriber/ResourceObjectNormalizerCacherTest.php
ResourceResponseSubscriber.php in core/modules/jsonapi/src/EventSubscriber/ResourceResponseSubscriber.php
SerializerTest.php in core/modules/jsonapi/tests/src/Kernel/Serializer/SerializerTest.php

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