Prism of Belief (Incinerate & Rake)

Hello everyone,

I'm experiencing the following bug with the Prism of Belief Incinerate +2 gem.

Is the following a bug or a display error in the damage overview for the Incinerate skill? Or is it as intended?

If you don't equip the gem before entering the map, but only after you've already entered the map or zone and then equip it, the expected damage increase isn't displayed or calculated.

I can confirm the same behavior with the Prism of Belief for Rake +2.

Other rare gems that increase spell damage, or if I play with a weapon set and one set doesn't have a +skill for the corresponding spell, and set 2, for example, a staff with +9 to skill, works so far, and the damage increase is displayed and is increased as expected (although we'd have to check whether the calculation is correct).