Fire Spell on Hit (Smith of Kitava) and Volcano

It won't let me socket Volcano into Fire Spell on Melee Hit, was excited to try out the one new fire spell on Smith. I assume this is because it's a channelling spell, however when I went looking for the reference text saying that channelling spells can't be triggered, I couldn't find it. Checking Volcano on spell totem seems to work just fine, and unlike some of the other spells (flameblast/incinerate), Volcano has a base instant cast version that could be it's triggered cast.

IDK, it just seems like a bug or an oversight. If all Channelling skills are meant to not be triggerable, maybe that should be added to one of the tool tips.

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