Enchanted books lose enchantments when upgrading

I was playing in my world after upgrading from 1.12.2 to 1.13-pre3 and I looked at an enchanted book and it didn't show the enchantments - also happened with villager trades.

I did a bit more testing and it seems to be easy to repeat with worlds upgrading from 1.12.2 to 1.13-pre3.