/usr/share/php/Symfony/ is in php-symfony-debug 3.4.6+dfsg-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/php/Symfony/Component/
/usr/share/php/Symfony/Component/Debug/
/usr/share/php/Symfony/Component/Debug/BufferingLogger.php
/usr/share/php/Symfony/Component/Debug/Debug.php
/usr/share/php/Symfony/Component/Debug/DebugClassLoader.php
/usr/share/php/Symfony/Component/Debug/ErrorHandler.php
/usr/share/php/Symfony/Component/Debug/Exception/
/usr/share/php/Symfony/Component/Debug/Exception/ClassNotFoundException.php
/usr/share/php/Symfony/Component/Debug/Exception/ContextErrorException.php
/usr/share/php/Symfony/Component/Debug/Exception/FatalErrorException.php
/usr/share/php/Symfony/Component/Debug/Exception/FatalThrowableError.php
/usr/share/php/Symfony/Component/Debug/Exception/FlattenException.php
/usr/share/php/Symfony/Component/Debug/Exception/OutOfMemoryException.php
/usr/share/php/Symfony/Component/Debug/Exception/SilencedErrorContext.php
/usr/share/php/Symfony/Component/Debug/Exception/UndefinedFunctionException.php
/usr/share/php/Symfony/Component/Debug/Exception/UndefinedMethodException.php
/usr/share/php/Symfony/Component/Debug/ExceptionHandler.php
/usr/share/php/Symfony/Component/Debug/FatalErrorHandler/
/usr/share/php/Symfony/Component/Debug/FatalErrorHandler/ClassNotFoundFatalErrorHandler.php
/usr/share/php/Symfony/Component/Debug/FatalErrorHandler/FatalErrorHandlerInterface.php
/usr/share/php/Symfony/Component/Debug/FatalErrorHandler/UndefinedFunctionFatalErrorHandler.php
/usr/share/php/Symfony/Component/Debug/FatalErrorHandler/UndefinedMethodFatalErrorHandler.php
/usr/share/php/Symfony/Component/Debug/autoload.php