Set slot represents writing a special NBT to the player's item to record how many enchanted slots the item currently has. You can set when to execute set slots through set-slots-trigger section at config.yml file.
# This is when will the plugin trying adds enchantment slot NBT for an enchantable item which also means set fixed# enchantment slot for an item.set-slot-trigger:add-hide-enchant-flag:falseblack-book:true# This option support ProtocolLib only.# Enable this maybe improve plugin performance.SetSlotPacket:enabled:true# Only plugin has enchantment slot NBT will be checked.remove-illegal-excess-enchant:trueEnchantItemEvent:enabled:true# Whether cancel the enchantment event or remove extra enchantment if# item reached slot limit after enchant.cancel-if-reached-slot:falseAnvilItemEvent:enabled:true# If your item has display issue after use anvil, you can try to enable this.update-item:falseSmithItemEvent:enabled:true# If set to true, we will reset old item enchantment slot and then regenerate new slot# value for new item, enchantments won't affect by this option.reset-previous-slot:true# If set to true, if new generated slot value smaller than existed slot value, we will still# # keep use existed value as new upgraded item's slot limit.keep-greater-slot:true# Enable this maybe improve plugin performance.# Maybe has incompatible issue with other plugins.InventoryClickEvent:enabled:true
Enchantable items without set slots will automatically calculate their enchanting slots through default-slots in the configuration file. This process consumes a lot of server performance, but the result is that the enchantment slots for the item are not fixed, which means that when player A drops the item to player B, the number of enchantment slots will change depending on the conditions met.