Thanks dRM, based on the photo we decided it's worth giving a try, and now I can return with the update:
Kopiscarjeva is completely snow free. Two patches from the photo are not near the trail. There is one patch just near the trail but the ferrata rope leads just into the gap between snow and the rock, so there is no need to step on the snow at all.
If I'm not mistaken, though, there seemed to be a snow patch on the linking traverse path Kopiscarjeva - Hanzova.