14 files declare their use of Environment

CKEditor5ImageController.php in core/modules/ckeditor5/src/Controller/CKEditor5ImageController.php
Cron.php in core/lib/Drupal/Core/Cron.php
editor.admin.inc in core/modules/editor/editor.admin.inc
EnvironmentTest.php in core/tests/Drupal/Tests/Component/Utility/EnvironmentTest.php
FileItem.php in core/modules/file/src/Plugin/Field/FieldType/FileItem.php
FileValidatorSettingsTrait.php in core/modules/file/src/Validation/FileValidatorSettingsTrait.php
FormBuilder.php in core/lib/Drupal/Core/Form/FormBuilder.php
FunctionalTestSetupTrait.php in core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php
ImportForm.php in core/modules/locale/src/Form/ImportForm.php
LargeQueryTest.php in core/modules/mysql/tests/src/Kernel/mysql/LargeQueryTest.php
node.module in core/modules/node/node.module
SettingsForm.php in core/modules/navigation/src/Form/SettingsForm.php
system.install in core/modules/system/system.install
Install, update and uninstall functions for the system module.
UploadedFileConstraintValidator.php in core/modules/file/src/Validation/Constraint/UploadedFileConstraintValidator.php

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