CTRL+F5强制刷新报错

问题：CTRL+F5强制刷新报错
Fatal error: Class Symfony\Component\Finder\Iterator\FileTypeFilterIterator contains 1 abstract method and must therefore be declared abstract or implement the remaining methods (FilterIterator::accept) in vendor\symfony\finder\Iterator\FileTypeFilterIterator.php on line 19
解决办法：重启web服务器
遗留问题：不知啥原因，待研究，期待网友解答