KeskinUpgrade v1.3.4

Fixed

• Fixed an item duplication issue that could occur when players clicked the upgrade button repeatedly in a short period of time.
• Fixed inventory desynchronization when rapidly switching held items before or during an upgrade attempt.
• Fixed cases where two different items could become mixed, overwritten, or duplicated inside the upgrade menu.
• Fixed rapid NPC interactions opening multiple upgrade sessions for the same player.
• Fixed delayed inventory updates applying changes to the wrong item.
• Fixed upgrade results being processed more than once from repeated menu clicks.
• Fixed items being returned multiple times when the upgrade menu was closed during an active operation.

Added

• Added a per-player upgrade transaction lock.
• Added a short configurable interaction cooldown for upgrade attempts.
• Added item identity validation before consuming materials or applying an upgrade.
• Added a final inventory validation immediately before completing the transaction.
• Added protection against hotbar switching, item swapping, shift-clicking, number-key swapping, dragging, double-clicking, and off-hand swapping during an active upgrade.
• Added safe session cleanup when a player closes the menu, disconnects, dies, changes worlds, or the plugin is disabled.

Improved

• Upgrade operations are now processed as a single protected transaction.
• The plugin now verifies that the item being upgraded is still the exact item selected when the menu was opened.
• Materials, XP, protection items, and the target item are now consumed and updated in a safer order.
• Inventory contents are refreshed after successful, failed, cancelled, or interrupted upgrade attempts.
• Repeated clicks during an active upgrade are ignored instead of creating additional operations.
• Improved compatibility with fast clicking, high latency, and delayed inventory packets.

Configuration

New anti-duplication settings:

security:
  transaction-lock:
    enabled: true

  upgrade-cooldown-milliseconds: 750

  block-inventory-actions-during-upgrade: true

  validate-item-before-upgrade: true
  validate-item-after-upgrade: true

  close-menu-on-item-mismatch: true

Compatibility

• Existing configuration files remain supported.
• Existing upgraded items and special blacksmith items remain compatible.
• No player data reset is required.
• FancyNpcs integration and the existing NPC action command remain unchanged:

yukseltadmin npcopen {player}