Add noopener noreferrer and nofollow to external listings links

In your WordPress dashboard, navigate to "Settings -> Posterno -> Listings". Locate and enable the option "Add noopener noreferrer and nofollow to external listings links".

For more information about these attributes and how they affect SEO please refer to this article https://www.forbes.com/sites/johnrampton/2017/11/06/the-difference-between-nofollow-and-noreferrer-and-why-it-matters/#466a59391e06