14 files declare their use of EntityFormMode

DisplayModeBundleSelectionTest.php in core/modules/field_ui/tests/src/FunctionalJavascript/DisplayModeBundleSelectionTest.php
DisplayModeUpdateTest.php in core/modules/field/tests/src/Kernel/DisplayModeUpdateTest.php
EntityDisplayModeTest.php in core/modules/field_ui/tests/src/Functional/EntityDisplayModeTest.php
EntityFormDisplayTest.php in core/modules/field_ui/tests/src/Kernel/EntityFormDisplayTest.php
EntityFormDisplayValidationTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntityFormDisplayValidationTest.php
EntityFormModeResourceTestBase.php in core/tests/Drupal/FunctionalTests/Rest/EntityFormModeResourceTestBase.php
EntityFormModeTest.php in core/modules/jsonapi/tests/src/Functional/EntityFormModeTest.php
EntityFormModeValidationTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntityFormModeValidationTest.php
EntityFormTest.php in core/modules/system/tests/src/Functional/Entity/EntityFormTest.php
EntityTypeTest.php in core/tests/Drupal/Tests/Core/Entity/EntityTypeTest.php
FieldUIRouteTest.php in core/modules/field_ui/tests/src/Functional/FieldUIRouteTest.php
LayoutBuilderFormModeTest.php in core/modules/layout_builder/tests/src/Functional/LayoutBuilderFormModeTest.php
ManageDisplayTest.php in core/modules/field_ui/tests/src/Functional/ManageDisplayTest.php
ManageFieldsMultipleTypesTest.php in core/modules/field_ui/tests/src/Functional/ManageFieldsMultipleTypesTest.php

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