Fatal error: Uncaught Error: Call to undefined function _deprecated_file() in /home/cezarypiatek1990/public_html/testwordpressa/wp-admin/includes/class-wp-upgrader-skins.php:11
Stack trace:
#0 {main}
thrown in /home/cezarypiatek1990/public_html/testwordpressa/wp-admin/includes/class-wp-upgrader-skins.php on line 11