https://lua-api.factorio.com/latest/pro ... t_category
Docs say the value is optional, but it doesn't say what happens when it is not provided. It seems that when not set, it uses all categories.
AtilleryFlareProtoype shot_category default behaviour
Re: AtilleryFlareProtoype shot_category default behaviour
Thanks for the note, I've added that information and a general description for the next doc release.
I'm an admin over at https://wiki.factorio.com. Feel free to contact me if there's anything wrong (or right) with it.

