17 files declare their use of ByteSizeMarkup

ByteSizeMarkupTest.php in core/tests/Drupal/Tests/Core/StringTranslation/ByteSizeMarkupTest.php
editor.admin.inc in core/modules/editor/editor.admin.inc
FileFieldDisplayTest.php in core/modules/file/tests/src/Functional/FileFieldDisplayTest.php
FileFieldValidateTest.php in core/modules/file/tests/src/Functional/FileFieldValidateTest.php
FileItem.php in core/modules/file/src/Plugin/Field/FieldType/FileItem.php
FileSize.php in core/modules/views/src/Plugin/views/field/FileSize.php
FileSize.php in core/modules/file/src/Plugin/Field/FieldFormatter/FileSize.php
FileSizeLimitConstraintValidator.php in core/modules/file/src/Plugin/Validation/Constraint/FileSizeLimitConstraintValidator.php
FileThemeHooks.php in core/modules/file/src/Hook/FileThemeHooks.php
FileTokenReplaceTest.php in core/modules/file/tests/src/Functional/FileTokenReplaceTest.php
FileWidgetAjaxController.php in core/modules/file/src/Controller/FileWidgetAjaxController.php
FormAjaxSubscriber.php in core/lib/Drupal/Core/Form/EventSubscriber/FormAjaxSubscriber.php
SystemRequirementsHooks.php in core/modules/system/src/Hook/SystemRequirementsHooks.php
TableFormatter.php in core/modules/file/src/Plugin/Field/FieldFormatter/TableFormatter.php
TokenHooks.php in core/modules/file/src/Hook/TokenHooks.php
umami.theme in core/profiles/demo_umami/themes/umami/umami.theme
Functions to support theming in the Umami theme.
UploadedFileConstraintValidator.php in core/modules/file/src/Validation/Constraint/UploadedFileConstraintValidator.php

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