Hyeeee guys. So i just played The Witcher 3 for 2 weeks(just reached skellige) . Finally i can play it. Okay forget about that. First Forgive me for my English. You might encounter a bug where you can't craft or brew potions but you sure you have the ingredients and diagrams for it. For me, it took 2 days found out what the heck happen and solved it. So the answer is.... Filter!!!! Just tick all the box and you good to go. Yeah it is not bug. Just idiot mistake. Hope this will help you. Good luck on the path!!!!