[@demon_ru Participant 4 years, 5 months ago]

With default 2020 theme is the same error with the same stack.
What else can i check?
How to localize an error?

[@demon_ru Participant 8 years, 6 months ago]

url 🙁

[@demon_ru Participant 8 years, 6 months ago]

I think it will be better:

$is_single = false;
if ( ! is_array( $user_ids ) ) {
$user_ids = wp_parse_id_list( $user_ids );
$is_single = count($user_ids) == 0;
}