The divisions drop down on the main tabs for the site doesn’t function properly when in the forums section. You can hover over it, but once you get down to fleet sec it disappears. It differs depending on the forum section your in, because once your mouse gets down to the actual threads is when the drop down disappears. I tested on IE v 9ish(super old), Chrome v. 44.0.2403.125, and Firefox v. 39.0 all exhibited the same behavior.
There are 100 different ways to get to that section of the forum, so it’s a very minor bug. However, I thought I would go ahead and make a post on it.