T10 set bonus bugged?

Hello, I recently acquired a second piece of the tier 10 raid set for locks, Dark Coven Hood. I already had the sanctified dark coven leggings. Since I have two pieces of the set, the 2 pieces set bonus should be highlighted ( The critical strike chance of your Shadowbolt, Incinerate, Soul Fire, and Corruption spells is increased by 5% ) but it isn't.

If anyone else has this error, I just wanted to know, is this a display error and is the effect still active? Or is it completely bugged and I have no bonus?

Also, I transmogrified the helmet pretty much after acquiring it, don't know if the appearance has anything to do with this bug, but the leggings are not transmogged and they are highlighted.

Thanks for your help!

It's a visual bug that happens when one of the items has been transmogrified, yes.