Summary:Extension talk:WYSIWYG/Working version for MW v1.20.2

my mediawiki install this version but has error message

strict standarda:Declaration of CKeditorParserOptions::getSkinshould be compatible with ParserOptions::getSkin($title = NULL) in C:\xampp\htdocs\mediawiki\extensions\WYSIWIYG\CKeditoorParserOptions.body.php on line 3

How could I fix it ?