A couple months ago, I found some instruction somewhere here on the XF boards to make it so that instead of grabbing my site logo image for Facebook thumbnails, it would let the user pick an image. That worked great. The problem now is that for some reason, Facebook is only seeing images when they are linked to the thread from outside of my site. So if someone posts photos that are hosted from Flickr, the images show up on Facebook. But if they uploaded them to my site, absolutely nothing comes up on Facebook, not even the site logo.
I don't know what changed that broke the functionality as it was all working a few weeks ago. I figure I need to determine what changes I made before in order to get to the root of the problem but I cannot for the life of me find it. I've found a few threads that detail solutions that might work for me but when I check my templates, the code does not match.
Specifically, I thought this template edit by @Jake Bunce might have been the one I used but neither the original or modified code is in my thread_view template.
Any ideas on how I can fix this?
Thread example with photos uploaded to my site (no thumbnails on FB):
Thread example with linked photos from Flickr (lots of thumbnails to choose from):