The bug
If an item has the same enchantment multiple times in 1.20.4 or earlier, and this item is upgraded to the latest 1.20.5 snapshot, subsequent instances of that enchantment disappear without a trace.
How to reproduce
A world containing a netherite pickaxe with two instances of Efficiency V is attached to this ticket.
Open this world in 1.20.4
Look inside the left chest
Open this world in the latest snapshot
Look in the left chest again
Expected results
In the latest version, either the two copies of the enchantment would remain, or they would be combined additively into one instance of a stronger enchantment (e.g. Efficiency II + Efficiency II = Efficiency IV).
Actual results
One of the instances of the enchantment is completely wiped from the item.
Thank you for your report!
After consideration, the issue is being closed as Working as Intended.
Please note, that mechanics of the game may change between updates.
Things such as graphics, sounds, world creation, biomes, redstone, villagers, and animals may not work the same in current versions.
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