Hi Valdan,
No change from Facebook’s end, or the open graph protocol for that matter.
Sounds like you have some sort of plug-in conflict, or possibly but less likely something in your theme is causing the issue.
My plug-in is designed to use the featured image as the open-graph image, or fall back to an image you specify. It’s entirely possible that you have a plug-in (or your theme as mentioned) that is also using the featured image but for the purpose of displaying it as a background image on your website, and that’s why you’re getting this issue.
The only thing I can suggest is to disable plug-ins one at a time until the problem goes away, then you’ll at least know which one is causing the issue.
The best way to test between plug-in deactivations is by using the Facebook debugger (https://developers.facebook.com/tools/debug/). Put your URL there and hit ‘Debug’. You may also have to hit the ‘Fetch new scrape information’ button to make sure Facebook isn’t pulling cached info from your website.
Failing that, you’d probably be able to find a plugin that does the same thing as mine does, but doesn’t use the featured image for Facebook.
Otherwise there is not a lot I can do as this is an issue outside of the control of my plug-in.
Good luck!