gform_entries_filter_count_queries

add_filter( 'gform_entries_filter_count_queries', 'your_function_name', 10, 2 );

$queries = array(
	"COUNT(DISTINCT CASE WHEN l.status='active' THEN l.id END) as total",
	"COUNT(DISTINCT CASE WHEN l.is_read=0 AND l.status='active' THEN l.id END) as unread",
	"COUNT(DISTINCT CASE WHEN l.is_starred=1 AND l.status='active' THEN l.id END) as starred",
	"COUNT(DISTINCT CASE WHEN l.status='spam' THEN l.id END) as spam",
	"COUNT(DISTINCT CASE WHEN l.status='trash' THEN l.id END) as trash",
);

add_filter( 'gform_entries_filter_count_queries', function ( $queries ) {
    $queries[] = "COUNT(DISTINCT CASE WHEN l.status='toxic' THEN l.id END) as toxic";

    return $queries;
} );