Enemies immune to chaos damage when ignite resistant and using blackflame unique ring

Steps to reproduce:

1. Equip blackflame unique ring and have arc as your damage spell with shaper of flames from elementalist ascendancy.
2. Fight a ignite/fire damage resistant enemy
3. Observe the issue of enemy not taking any damage besides arc hit damage albeit the blackflame should convert the damage to chaos damage which should penetrate the ignite / fire resistance.