Villagers not remembering correct profession

The bug

Converting a librarian into a zombie villager and back has 50% chance to become a cartographer which is not supposed to happen.

How to reproduce

1. Dig a hole 6 x 4, spawn 4 librarians

   /summon minecraft:villager ~ ~ ~ {Profession:1, Career:1}

2. Let zombies turn the villagers into zombie villagers
3. Cure the zombie villagers and wait
   → Check the professions and observe how the villager is a cartographer