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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