Bug: esc_url() called with array argument

On line 137 of bp-blacklist-signup-by-email-domain.php the following is called:

implode(', ', esc_url($allowed_domains))

This won’t work because $allowed_domains is an array and esc_url requires a string. It results in a fatal error.

One solution is to map esc_url() to the array beforehand:

$allowed_domains = array_map(
            'esc_url',
            $allowed_domains
        );