Cruelty support with fire trap

Hello, it seems that cruelty support is not working with fire trap. When you equip the support, the damage of the hit increases but it never triggers the buff. My build is based on both EO and cruelty and it's disappointing that neither of them works :(

here is a short clip with the bug hopefully it will get fixed :( since i lose 80% more dmg from both cruelty and EO...

https://www.youtube.com/watch?v=_Gn9U3wrJ8Y