A user has written that Weber gypsum primer works according to his experience. But it's really troublesome if it does NOT work well and you notice it too late. So I would be very grateful for more responses from others with experience and knowledge.
According to the product information, only Promafour Primer from PROMAT is suitable. It's barely accessible for a private individual.
I've been googling for several hours now without being sure what to do. I've also emailed different companies but they don't dare to respond or something.
