Not sure if it's always been like this but I noticed that the tooltip for the hexed condition is not showing up when you hover over an ability that relates to it, nor is it highlighted like other conditions. Noticed it first when looking at Revel in Misery as diseased and cursed are both in bold and have their tooltips show up.
There is also a dead "Hexed" tooltip that shows up on champions with Hex 1 (Collection of Souls, maybe one other champ), which does generate a tooltip popup but has no description.