Blocking any domain seems to make certain stuff disappear

I moderate @mcsuggestions, and today, I noticed that my comments on the two most recent threads didn't show up when I was logged in. After some experimentation, I figured out that whenever I had any domain blocked, all comments on those threads disappeared. From what I can tell in this magazine, others are experiencing the same problem. What's causing this?

And, while we're here, why am I taken to an error page every time I make a thread? That's also odd.

Edit: Haha, just remembered something based on another bug that occurred with this thread.

Those two threads I mentioned each had 4-5 copies that I had to delete. I assume that maybe it was a mistake due to the error page when you post a thread, but it turns out that this very thread posted twice somehow. Maybe that's part of the cause here?