Basically instead of the site displaying the code (an image or a notification bubble), the site is trying to load the code as a webpage instead. It's replicable just by scrolling around, but KN hasn't figured out the cause.
I'm going to willingly blind myself by reverting the site skin to the default to see if it stops. Anyone else willing can join me in this already-painful test.
I will let KN know when I get home, I actually got an error too.
It could be something related to the skin, but weird that it started now instead of a year ago.