Fatal error: Uncaught Error: Class "SebastianBergmann\Comparator\ObjectComparator" not found in C:\AppServ\Apache\2.4.58\htdocs\sets\vendor\sebastian\comparator\src\DOMNodeComparator.php:21 Stack trace: #0 {main} thrown in C:\AppServ\Apache\2.4.58\htdocs\sets\vendor\sebastian\comparator\src\DOMNodeComparator.php on line 21