Hello cbaltrin,
Thank you for bringing this to our attention!
There are a couple of different things at play here:
- SSL(https)
- Legacy Code/Technology
- iFrames
When this feature initially stopped functioning it was because we upgraded/added SSL security certificates. This is obviously a necessity and important. Unfortunately legacy technology, such as iFrames, does not play nicely with today's modern technology - it is a mostly dying implementation these days. Anyways, I was able to implement a workaround to where the "Private message" button on a User's Profile page will now take you to a new page (with https) instead of attempting via iframe popup. I also did the same thing for the "Add Friend" button on that page, as it was experiencing the same issue.
This is obviously not the most ideal solution, but I hope it at least improves upon the current user experience a bit more. I know how frustrating it can be losing basic functionality that you've grown acustom to for years.
Happy Holidays,
Zakk