30 files declare their use of FilterFormatInterface

CKEditor4To5UpgradePluginInterface.php in core/modules/ckeditor5/src/Plugin/CKEditor4To5UpgradePluginInterface.php
CKEditor4To5UpgradePluginManager.php in core/modules/ckeditor5/src/Plugin/CKEditor4To5UpgradePluginManager.php
CKEditor5.php in core/modules/ckeditor5/src/Plugin/Editor/CKEditor5.php
CKEditor5UpdateImageToolbarItemTest.php in core/modules/ckeditor5/tests/src/Functional/Update/CKEditor5UpdateImageToolbarItemTest.php
CKEditor5ValidationTestTrait.php in core/modules/ckeditor5/tests/src/Kernel/CKEditor5ValidationTestTrait.php
CKEditorAdminTest.php in core/modules/ckeditor/tests/src/Functional/CKEditorAdminTest.php
Contrib.php in core/modules/ckeditor5/src/Plugin/CKEditor4To5Upgrade/Contrib.php
Core.php in core/modules/ckeditor5/src/Plugin/CKEditor4To5Upgrade/Core.php
editor.api.php in core/modules/editor/editor.api.php
Documentation for Text Editor API.
editor.module in core/modules/editor/editor.module
Adds bindings for client-side "text editors" to text formats.
EditorController.php in core/modules/editor/src/EditorController.php
EditorXssFilterInterface.php in core/modules/editor/src/EditorXssFilterInterface.php
editor_test.module in core/modules/editor/tests/modules/editor_test/editor_test.module
Helper module for the Text Editor tests.
filter.module in core/modules/filter/filter.module
Framework for handling the filtering of content.
FilterController.php in core/modules/filter/src/Controller/FilterController.php
FilterFormat.php in core/modules/filter/src/Entity/FilterFormat.php
FundamentalCompatibilityConstraintValidator.php in core/modules/ckeditor5/src/Plugin/Validation/Constraint/FundamentalCompatibilityConstraintValidator.php
HTMLRestrictions.php in core/modules/ckeditor5/src/HTMLRestrictions.php
HTMLRestrictionsTest.php in core/modules/ckeditor5/tests/src/Unit/HTMLRestrictionsTest.php
Insecure.php in core/modules/editor/tests/modules/editor_test/src/EditorXssFilter/Insecure.php
MediaFilterController.php in core/modules/media/src/Controller/MediaFilterController.php
MigrateEntityContentValidationTest.php in core/modules/migrate/tests/src/Kernel/MigrateEntityContentValidationTest.php
MigrateFilterFormatTest.php in core/modules/filter/tests/src/Kernel/Migrate/d7/MigrateFilterFormatTest.php
MigrateFilterFormatTest.php in core/modules/filter/tests/src/Kernel/Migrate/d6/MigrateFilterFormatTest.php
SmartDefaultSettings.php in core/modules/ckeditor5/src/SmartDefaultSettings.php
Standard.php in core/modules/editor/src/EditorXssFilter/Standard.php
TestMediaFilterController.php in core/modules/media/tests/modules/media_test_embed/src/Controller/TestMediaFilterController.php
TextEditorObjectDependentValidatorTrait.php in core/modules/ckeditor5/src/Plugin/Validation/Constraint/TextEditorObjectDependentValidatorTrait.php
user.module in core/modules/user/user.module
Enables the user registration and login system.
ValidatorsTest.php in core/modules/ckeditor5/tests/src/Kernel/ValidatorsTest.php

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