Fatal error: Uncaught Error: Call to undefined function add_filter() in C:\xampp\htdocs\WAIT FOR DELETE\wp-content\plugins\jetpack\modules\custom-css\custom-css\preprocessors.php:32 Stack trace: #0 C:\xampp\htdocs\WAIT FOR DELETE\wp-content\plugins\jetpack\modules\custom-css\custom-css.php(1954): require_once() #1 {main} thrown in C:\xampp\htdocs\WAIT FOR DELETE\wp-content\plugins\jetpack\modules\custom-css\custom-css\preprocessors.php on line 32