Just noticed the Data Explorer received a minor facelift, and the help icons in the schema panel which enumerated the different types(posttypes, posthistorytypes, postlinktypes, etc.) is now MIA. Is this a temporary change, or a new policy?
Fixed, pending a pull and redeploy.
I'm not sure how it got broken because the problem suggests it shouldn't have ever been working to begin with, but at least it's taken care of now.