8 files declare their use of EntityDisplayInterface

EntityDisplayBase.php in core/lib/Drupal/Core/Entity/EntityDisplayBase.php
EntityDisplayFormBaseTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntityDisplayFormBaseTest.php
EntityDisplayTest.php in core/modules/field_ui/tests/src/Kernel/EntityDisplayTest.php
EntityDisplayWithLayoutInterface.php in core/modules/field_layout/src/Display/EntityDisplayWithLayoutInterface.php
field_layout.install in core/modules/field_layout/field_layout.install
Contains install and update functions for Field Layout.
LayoutEntityDisplayInterface.php in core/modules/layout_builder/src/Entity/LayoutEntityDisplayInterface.php
system.post_update.php in core/modules/system/system.post_update.php
Post update functions for System.
text.post_update.php in core/modules/text/text.post_update.php
Contains post update hooks for the text module.

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