I am getting an error while trying to display certain categories on my Wordpress Site. This is the error message:
Catchable fatal error: Object of class WP_Term could not be converted to string in ...public_html/wp-includes/class-wp-query.php on line 780
line 780 :
$qv['cat'] = preg_replace( '|[^0-9,-]|', '', $qv['cat'] );
The error only happens for parent categories without a special archive template. Anyone with an idea what I got wrong?