This Minecraft, Bukkit plugin prevents players from placing lava blocks or emptying/filling buckets. It supports Permissions using the node StopLava.canUseLava or reverts back to only allowing use by Ops.
When cancelling a PlayerBucketFillEvent, or PlayerBucketEmptyEvent the client is not notified of the event actually being cancelled. So the player will see the bucket being filled, while it isn't really. As will be clear when the player (dis)connects and gets the update.
This is now 'fixed' by calling Player.updateInventory(). But that is a temporary workaround by the developers of Bukkit.
Bug report created for this: https://bukkit.atlassian.net/browse/BUKKIT-1339
Source can be found at https://github.com/ArmEagle/StopLava
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