10 files declare their use of InvalidStreamWrapperException

CopyTest.php in core/modules/file/tests/src/Kernel/CopyTest.php
file.inc in core/includes/file.inc
API for handling file uploads and server file management.
file.module in core/modules/file/file.module
Defines a "managed_file" Form API field and a "file" field for Field module.
FileRepository.php in core/modules/file/src/FileRepository.php
FileRepositoryTest.php in core/modules/file/tests/src/Kernel/FileRepositoryTest.php
FileUploadHandler.php in core/modules/file/src/Upload/FileUploadHandler.php
FileUrlGenerator.php in core/lib/Drupal/Core/File/FileUrlGenerator.php
FileUrlGeneratorTest.php in core/tests/Drupal/KernelTests/Core/File/FileUrlGeneratorTest.php
MoveTest.php in core/modules/file/tests/src/Kernel/MoveTest.php
system.module in core/modules/system/system.module
Configuration system that lets administrators modify the workings of the site.

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