It’s really a shame that this feature has no scripting support to work with other non-Google/Enterprise level adserver type software or programs out there. I have been running an independent ad server for 20 years on my sites, and this has really made it almost impossible for me to monetize my forums other than with Google ads. And there is seemingly no way to get it to work via the custom CSS/HTML options for Discourse as well because you have taken it upon yourselves to parse out all potentially harmful scripting from these custom fields. Just FYI some of us are developers as well, perhaps not Ruby, etc. but we still know how to implement 3rd party scripting from other servers/instances we manage and control the content on. Sorry but just frustrated because after 3 years and many updates of the current Ad server software I am using (AdAdmin) there is apparently still no version of the ad script call that will work within your code limitations. 