Fulminating Concoction dps breakdown tooltip not workin

The dps breakdown tooltip on Fulminating Concoction is not working properly, or the skill is not properly adding bow affixes.

First of all, it shows two breakdowns - one for mainhand damage and one for offhand damage. Is that supposed to happen? As far as I remember before level 60-ish there was only main hand damage.

Second of all, changing bows only changes the dps if the +level to projectile skills is different. Exchanging two different bows with the same +level does not affect the dps tooltip at all. Both bows have some additive damage (one fire and one physical) and the tooltip doesn't change when I change the bows.

One of the bows has +crit damage, it does not affect the tooltip (still says 100% crit damage, all other skills correctly shows +128%).

I'm level 71, Concoctions is level 16. I don't remember that happening before, I was watching the tooltip every time I was changing bows, so quite a lot.