13 files declare their use of Bytes

BytesTest.php in core/tests/Drupal/Tests/Component/Utility/BytesTest.php
CKEditor5ImageController.php in core/modules/ckeditor5/src/Controller/CKEditor5ImageController.php
color.module in core/modules/color/color.module
Allows users to change the color scheme of themes.
common.inc in core/includes/common.inc
Common functions that many Drupal modules will need to reference.
EditorImageDialog.php in core/modules/editor/src/Form/EditorImageDialog.php
FileItem.php in core/modules/file/src/Plugin/Field/FieldType/FileItem.php
FileUploadResource.php in core/modules/file/src/Plugin/rest/resource/FileUploadResource.php
FileValidationConstraintValidator.php in core/modules/file/src/Plugin/Validation/Constraint/FileValidationConstraintValidator.php
MaximumFileSizeExceededUploadTest.php in core/modules/file/tests/src/FunctionalJavascript/MaximumFileSizeExceededUploadTest.php
MigrateExecutable.php in core/modules/migrate/src/MigrateExecutable.php
SizeTest.php in core/tests/Drupal/KernelTests/Core/Common/SizeTest.php
system.install in core/modules/system/system.install
Install, update and uninstall functions for the system module.
TemporaryJsonapiFileFieldUploader.php in core/modules/jsonapi/src/Controller/TemporaryJsonapiFileFieldUploader.php

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