Problem with mutagen alchemy (The Witcher 3: Wild Hunt)

You need a "Big XS Mutagen", to craft it you need to make a "GZS Mutagen". The menu says that there are "3/3 small xz mutagens" for this, but they don't let me craft, because I already have two of these mutagens in my backpack.
The problem is solved by temporarily throwing mutagens out of the backpack... There was no such garbage before patch 1.05.