Observed on a Mage in Unique mode. Looking over other items in Aberrus and Zaralek Caverns, it seems it's applicable to almost anything there (like bosses, rares, ...)

This is fixed for next release. Every patch we have to harvest all the item data from the battle.net API to properly assign all those filters without us needing to manually make those changes. So it's typically always like this for the first week of every patch :)