Fatal error: Uncaught Error: Class 'WP_Widget' not found in H:\root\home\agubski-002\www\alexgubski\blog\wp-includes\widgets\class-wp-widget-calendar.php:17
Stack trace:
#0 {main}
thrown in H:\root\home\agubski-002\www\alexgubski\blog\wp-includes\widgets\class-wp-widget-calendar.php on line 17