Engineering bombs not usable in dungeons?

[Handshandy-defias-brotherhood]

A number of guides identify crafting bombs as a viable engineering specialisation. However, I’ve just tested Primal Deconstruction Charges in a heroic dungeon and received a message saying that they can’t be used here. There’s a couple of very recent wowhead posts saying the same thing.

Is this an undocumented hotfix or just a bug (or have I somehow goofed…)?

Update: there is a thread on the US forums saying they can’t use bombs in dungeons either. However, I’ve just done Mythic 0 Offensive and they worked fine.

[Varuul-das-konsortium]

I wanted to use bombs more since I hadn’t since back in WotLK. Invested 35 knowledge points and my first specialization into it, just to find out today, that I couldn’t use them in dungeons. They already seemed questionable with the long cooldown, but making them not usable at all without telling is infuriating.