What's with the black band on top of the page? ANSWERED

There seems to be an extra td on top of the page, containing a fairly "empty" gif (https://news.ycombinator.com/s.gif). After a quick look with a random hex viewer, I can't see anything interesting in that gif. This doesn't seem to accomplish anything on the page, so, what gives?

Here is a screenshot: https://imgur.com/a/dY6czCs