I was able to restore most blueprints by now. I found a .16 save from a server where a lot of blueprints are saved.

My BP library is empty, altought the blueprint-storage.dat seems to still have its data.
I tried to use the backups, but they didnt work either.
Quickbar references turned into questionmarks that say "The target of this shortcut to the blueprint library is no longer present".
Note that i dont use ...

What?

Hide the equipment box when you hover over an object that has more Information that your screen can Show.

Why?

The box is over the description of the object, so you cant see what is under it.