10 files declare their use of FieldUI in Drupal 10

EntityDisplayFormBase.php in core/modules/field_ui/src/Form/EntityDisplayFormBase.php

EntityFormDisplayEditForm.php in core/modules/field_ui/src/Form/EntityFormDisplayEditForm.php

FieldConfigDeleteForm.php in core/modules/field_ui/src/Form/FieldConfigDeleteForm.php

FieldConfigEditForm.php in core/modules/field_ui/src/Form/FieldConfigEditForm.php

FieldStorageAddForm.php in core/modules/field_ui/src/Form/FieldStorageAddForm.php

FieldStorageConfigEditForm.php in core/modules/field_ui/src/Form/FieldStorageConfigEditForm.php

FieldUiTest.php in core/modules/field_ui/tests/src/Unit/FieldUiTest.php

field_ui.module in core/modules/field_ui/field_ui.module

Allows administrators to attach custom fields to fieldable types.

MediaLibraryWidget.php in core/modules/media_library/src/Plugin/Field/FieldWidget/MediaLibraryWidget.php

WidgetWithoutTypesTest.php in core/modules/media_library/tests/src/FunctionalJavascript/WidgetWithoutTypesTest.php