Steps to reproduce:
Have a relationship with a villager that allows you to receive a discount
Ex: trade 2 melons instead of 3 for 1 emerald
Have just enough of one stack of an item in inventory to trade with villager at the discounted price
Ex: have 2 melons in inventory
Attempt to trade with villager
Observed:
Trade cannot be completed successfully
Clicking on resulting item (ex: emerald) artificially increases villager EXP
Clicking on resulting item continuously eventually maxes out trade for that trade session with villager
Desired:
Trade happens normally
Workaround:
Have enough items in your inventory to complete the trade at the non-discounted price
Ex: have 3 melons in inventory
Trade with villager works at discounted price
Ex: with 3 melons -> trade -> inventory is now 1 melon and 1 emerald
Duplicate of MC-148454