to my knowledge no most venders stopped using it just as a precaution, I think those that do use it put a note/warning about it
Not really. Many replaced diacetyl with acetyl propionyl or butyric acid, which is also a questionable ingredient.
I want to vape some desert juices, and I’m not afraid of it or anything but I don’t want to vape anything with diacetyl in it.
When in doubt, contact the manufacturer directly and ask. And, BTW, diketones are present in other flavors also, like fruit, not just dessert, buttery, caramel-type flavors. If you really want to avoid all diketones and butyric acid, you'll have to DIY and use flavorings from manufacturers who fully disclose their ingredients, like FlavorArt, or the Flavor Apprentice, for example.
