The Mysterious Twitter Auto-Feed populated in my posts

Whenever I make a new post, and there is a link to my twitter on that page, WordPress appears to be automatically replacing that link to Twitter with a full-width Twitter feed instead. I DO NOT want that. I want to disable it. Problem is, I cannot figure out what is causing it. I’ve even disabled all my plugins, and the SOB still appears.

The site is here:

It doesn’t appear on all of the posts… just the latest ones. I look at posts a few months back, and the site is NOT doing that to the links. Older posts look at intended. For some reason, WordPress is pretty much ruining my posts lately by embedding my Twitter, which I do not want. To my knowledge, I’ve added no functionality that does this, and none of my plugins appear to be doing is, as I’ve tried posting a new article with NO plugins on, and it still shows up now.

How do I turn this off so that it never comes back, anywhere, again? Thanks! Support access has been granted already.