When you create a villager from a spawn egg and you go to make a quick purchase by holding down the shift key, it will purchase as many enchanted books that the intended book will allow and what ever left over emeralds you have will be spent on less expensive enchanted books.
For example say an Enchanted book cost 35 emeralds from a villager, but the villager also has another enchanted book for the cost of 10 emeralds. With a stack of 64 emeralds, you will purchase the 1 enchanted book that cost 35 emeralds, and the remaining 29 emeralds will then be also spent on two enchanted book for 10 emeralds leaving you with 9 emeralds and your inventory will have 3 books, the one that cost 35, and 2 that cost you 10. This only happens when you create the villager from a spawn egg. I have only tested this in 1.16.5, but it is doing this in single player and on the realm.
The result of this bug is causing unwanted purchases of unnecessary items.
Linked issues
Comments 2
Thank you for your report!
We're tracking this issue in MC-209286, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
Quick Links:
📓 Bug Tracker Guidelines – 💬 Community Support – 📧 Mojang Support
📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki
The way I tested this was in a new game, I moved to a village and trapped a villager, placing down a lectern, I then had the villager with an enchanted book for sell. I then leveled up that villager and tested it when another book became available, and it responded by only selling me the one book. I then used the spawn egg to create another villager and put down another lectern and followed the same process. The first book was at 18 and the second was for 6. I then placed 18+6 emeralds into the slot to do a quick purchase and I got both books, instead of only getting the intended book as it would normally work if the villager did not come from a spawn egg.