34 files declare their use of ImageStyle

ConfigEntityImportTest.php in core/modules/system/tests/src/Kernel/Entity/ConfigEntityImportTest.php
FileMoveTest.php in core/modules/image/tests/src/Functional/FileMoveTest.php
image.module in core/modules/image/image.module
Exposes global functionality for creating image styles.
ImageAdminStylesTest.php in core/modules/image/tests/src/FunctionalJavascript/ImageAdminStylesTest.php
ImageAdminStylesTest.php in core/modules/image/tests/src/Functional/ImageAdminStylesTest.php
ImageDimensionsTest.php in core/modules/image/tests/src/Functional/ImageDimensionsTest.php
ImageEffectsTest.php in core/modules/image/tests/src/Functional/ImageEffectsTest.php
ImageFieldAttributesTest.php in core/modules/rdf/tests/src/Functional/ImageFieldAttributesTest.php
ImageFieldDisplayTest.php in core/modules/image/tests/src/Functional/ImageFieldDisplayTest.php
ImageFormatter.php in core/modules/image/src/Plugin/Field/FieldFormatter/ImageFormatter.php
ImageFormatterTest.php in core/modules/image/tests/src/Kernel/ImageFormatterTest.php
ImageImportTest.php in core/modules/image/tests/src/Kernel/ImageImportTest.php
ImageStyleCustomStreamWrappersTest.php in core/modules/image/tests/src/Kernel/ImageStyleCustomStreamWrappersTest.php
ImageStyleFlushTest.php in core/modules/image/tests/src/Functional/ImageStyleFlushTest.php
ImageStyleIntegrationTest.php in core/modules/image/tests/src/Kernel/ImageStyleIntegrationTest.php
ImageStyleResourceTestBase.php in core/modules/image/tests/src/Functional/Rest/ImageStyleResourceTestBase.php
ImageStylesPathAndUrlTest.php in core/modules/image/tests/src/Functional/ImageStylesPathAndUrlTest.php
ImageStyleTest.php in core/modules/jsonapi/tests/src/Functional/ImageStyleTest.php
ImageThemeFunctionTest.php in core/modules/image/tests/src/Kernel/ImageThemeFunctionTest.php
ImageWidget.php in core/modules/image/src/Plugin/Field/FieldWidget/ImageWidget.php
MediaLibraryAccessTest.php in core/modules/media_library/tests/src/Kernel/MediaLibraryAccessTest.php
MediaLibraryDisplayModeTest.php in core/modules/media_library/tests/src/Functional/MediaLibraryDisplayModeTest.php
MediaLibraryUpdateFormAndViewDisplaysTest.php in core/modules/media_library/tests/src/Functional/Update/MediaLibraryUpdateFormAndViewDisplaysTest.php
MediaSourceImageTest.php in core/modules/media/tests/src/FunctionalJavascript/MediaSourceImageTest.php
media_library.module in core/modules/media_library/media_library.module
Contains hook implementations for the media_library module.
media_library.post_update.php in core/modules/media_library/media_library.post_update.php
Post update functions for Media Library.
MigrateImageCacheTest.php in core/modules/image/tests/src/Kernel/Migrate/d6/MigrateImageCacheTest.php
MigrateImageStylesTest.php in core/modules/image/tests/src/Kernel/Migrate/d7/MigrateImageStylesTest.php
ResponsiveImageFieldDisplayTest.php in core/modules/responsive_image/tests/src/Functional/ResponsiveImageFieldDisplayTest.php
ResponsiveImageStyle.php in core/modules/responsive_image/src/Entity/ResponsiveImageStyle.php
responsive_image.module in core/modules/responsive_image/responsive_image.module
Responsive image display formatter for image fields.
StandardProfileTest.php in core/modules/rdf/tests/src/Functional/StandardProfileTest.php
UserPictureTest.php in core/modules/user/tests/src/Functional/UserPictureTest.php
ViewsConfigDependenciesIntegrationTest.php in core/modules/views/tests/src/Kernel/ViewsConfigDependenciesIntegrationTest.php

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