So far, works like a charm, at least on Facebook, where I've tried it. I love that it also blocks the part where it says 'x comments x shares' that's really annoying. The posts look seamless now and way less distracting. Thank you.
EDIT: This slows down, at the very least, Youtube. At the very least, I opened a YT playlist and I got a message saying this addon was slowing YT down and the images wouldn't load. I already have Distraction Free Youtube and I'd like to enable this addon ONLY for Facebook, please add an option for this. Thank you.

Doesn't work on any other website.