On SuperUser, I found a question that belonged on another site: the question and answer were good, but it was off topic. I tried clicking Close --> Off topic --> This belongs on another SE site --> Choose the site (Webmasters), and then the menu disappears! The question is still there, and it says "
This error has been logged" in a red bar at the top of the screen. If I follow the same process but chose to Flag, then Close, it happens then as well.
Version 0.1.68 and 0.1.70