Invisible Youtube loading bar for Firefox 5.0.1 (9/14, it fixed itself?)

I'm not sure how opening FF in safe can rectify the problem, and I pretty much carry only the essential plug-ins, so disabling them is a rather bad/moot idea. I did disable a couple useless ones that snuck into my browser like the downloadUpdater ones, but that didn't do much since they were plugins given to me from AOL.