7 files declare their use of FieldTypeCategoryManagerInterface

BaseFieldDefinitionTestBase.php in core/tests/Drupal/Tests/Core/Field/BaseFieldDefinitionTestBase.php
comment.module in core/modules/comment/comment.module
Enables users to comment on published content.
FieldStorageAddForm.php in core/modules/field_ui/src/Form/FieldStorageAddForm.php
FieldTypePluginManagerTest.php in core/tests/Drupal/Tests/Core/Field/FieldTypePluginManagerTest.php
link.module in core/modules/link/link.module
Defines simple link field types.
media.module in core/modules/media/media.module
Provides media items.
telephone.module in core/modules/telephone/telephone.module
Defines a simple telephone number field type.

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