I was just looking at the latest Stack Overflow blog post and noticed that the blog site's header is messed up.
When the page first loads, as shown in the image below, there are links that are covered up by the top bar.
From inspecting the code, I can see that the links are supposed to go to the Company, Code for a Living, Insights, Engineering and Podcast pages. The only reason I noticed them is because you can see them sticking out a bit on the bottom. Also, if you look closely, you can see the Stack Overflow Blog logo from behind the black bar.
When you scroll down a bit, the black bar gets thicker, so you can't see any links sticking out, but I'm assuming the links are still hidden under the bar. Also, you can still see the words "Stack Overflow" very faintly through the black bar:
I was able to reproduce this bug in both Chrome and Firefox.