22 files declare their use of MediaType

media.install in core/modules/media/media.install
Install, uninstall and update hooks for Media module.
Media.php in core/modules/ckeditor5/src/Plugin/CKEditor5Plugin/Media.php
MediaCreationTest.php in core/modules/media/tests/src/Kernel/MediaCreationTest.php
MediaLibraryDisplayModeTest.php in core/modules/media_library/tests/src/Functional/MediaLibraryDisplayModeTest.php
MediaLibraryWidgetTest.php in core/modules/media_library/tests/src/Kernel/MediaLibraryWidgetTest.php
MediaResourceTestBase.php in core/modules/media/tests/src/Functional/Rest/MediaResourceTestBase.php
MediaSourceImageTest.php in core/modules/media/tests/src/FunctionalJavascript/MediaSourceImageTest.php
MediaSourceOEmbedVideoTest.php in core/modules/media/tests/src/FunctionalJavascript/MediaSourceOEmbedVideoTest.php
MediaSourceTest.php in core/modules/media/tests/src/Kernel/MediaSourceTest.php
MediaSourceTestBase.php in core/modules/media/tests/src/FunctionalJavascript/MediaSourceTestBase.php
MediaTest.php in core/modules/jsonapi/tests/src/Functional/MediaTest.php
MediaTypeCreationTest.php in core/modules/media/tests/src/Functional/MediaTypeCreationTest.php
MediaTypeCreationTrait.php in core/modules/media/tests/src/Traits/MediaTypeCreationTrait.php
MediaTypeForm.php in core/modules/media/src/MediaTypeForm.php
MediaTypeResourceTestBase.php in core/modules/media/tests/src/Functional/Rest/MediaTypeResourceTestBase.php
MediaTypeTest.php in core/modules/jsonapi/tests/src/Functional/MediaTypeTest.php
MediaUiJavascriptTest.php in core/modules/media/tests/src/FunctionalJavascript/MediaUiJavascriptTest.php
media_library.install in core/modules/media_library/media_library.install
Install, update and uninstall functions for the media_library module.
OEmbedFormatter.php in core/modules/media/src/Plugin/Field/FieldFormatter/OEmbedFormatter.php
OEmbedWidget.php in core/modules/media/src/Plugin/Field/FieldWidget/OEmbedWidget.php
PathMediaFormTest.php in core/modules/path/tests/src/Functional/PathMediaFormTest.php
StandardTest.php in core/profiles/standard/tests/src/Functional/StandardTest.php

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