Fatal error: Uncaught Error: Call to undefined function post_class() in /home/simon04/public_html/projektinformatyka/wordpress/wp-includes/theme-compat/embed-content.php:13 Stack trace: #0 {main} thrown in /home/simon04/public_html/projektinformatyka/wordpress/wp-includes/theme-compat/embed-content.php on line 13