9 files declare their use of FieldTypeCategoryManagerInterface

BaseFieldDefinitionTestBase.php in core/tests/Drupal/Tests/Core/Field/BaseFieldDefinitionTestBase.php
CommentHooks.php in core/modules/comment/src/Hook/CommentHooks.php
FieldStorageAddController.php in core/modules/field_ui/src/Controller/FieldStorageAddController.php
FieldStorageAddForm.php in core/modules/field_ui/src/Form/FieldStorageAddForm.php
FieldTypePluginManagerTest.php in core/tests/Drupal/Tests/Core/Field/FieldTypePluginManagerTest.php
LinkHooks.php in core/modules/link/src/Hook/LinkHooks.php
MediaHooks.php in core/modules/media/src/Hook/MediaHooks.php
telephone.module in core/modules/telephone/telephone.module
Defines a simple telephone number field type.
TelephoneHooks.php in core/modules/telephone/src/Hook/TelephoneHooks.php

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