12 files declare their use of EntityFormDisplayInterface

ContentEntityForm.php in core/lib/Drupal/Core/Entity/ContentEntityForm.php
ContentEntityFormInterface.php in core/lib/Drupal/Core/Entity/ContentEntityFormInterface.php
content_moderation.module in core/modules/content_moderation/content_moderation.module
Contains content_moderation.module.
EntityDisplayRepositoryTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntityDisplayRepositoryTest.php
EntityFormDisplay.php in core/lib/Drupal/Core/Entity/Entity/EntityFormDisplay.php
layout_builder_test.module in core/modules/layout_builder/tests/modules/layout_builder_test/layout_builder_test.module
Provides hook implementations for Layout Builder tests.
MediaSourceBase.php in core/modules/media/src/MediaSourceBase.php
MediaSourceInterface.php in core/modules/media/src/MediaSourceInterface.php
MigrateFieldInstanceWidgetSettingsTest.php in core/modules/field/tests/src/Kernel/Migrate/d7/MigrateFieldInstanceWidgetSettingsTest.php
OEmbed.php in core/modules/media/src/Plugin/media/Source/OEmbed.php
TestDifferentDisplays.php in core/modules/media/tests/modules/media_test_source/src/Plugin/media/Source/TestDifferentDisplays.php
TestWithHiddenSourceField.php in core/modules/media/tests/modules/media_test_source/src/Plugin/media/Source/TestWithHiddenSourceField.php

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