Page works in dev environment, but not in production

I have a page that is pulling html content into an iframe that is generated from user input. in the dev environment, it works brilliantly. after pushing to production, the page does not function.

the only difference between environments (that i can tell) is that there is a TLS error on the domains “contact support” in the production environment. otherwise, they are “the same”…

Any idea why this would be the case?

Check the console for errors, it could be something as simple as a setting in the hosts environment.
It does sound like it has to do with some miss-matched domain.