Prevent Nether Portals From Spawning

When a player creates an Obsidian square, they have the option to light it into a nether portal by placing fire somewhere inside that square. How do I prevent that fire from lighting up into a nether portal without doing things like banning Flint & Steel usage (which wouldn’t solve the problem as there are other ways of creating fire)?

I’ve looked in the event package but there’s no event linked to this other than PlaceBlockEvent, and I don’t know if the fire turning into the Portal (ID 90) would trigger such an event. If it does though, PlaceBlockEvent would solve my problem.

In the refactor/event-names we are adding actual portal support, including portal creation events.


Has the API been written yet, though?