What kind of SSL do you use on your forum? Is it free SSL that you can get from Let's Encrypt or are you paying money for your SSL? One of my forums, which is on the subdirectory, uses Let's Encrypt. One of my forums does not have SSL because I have not been able to renew SSL due to a lack of budget. I could have used Lets Encrypt but I do not have the skills to use Let's Encrypt on a forum.