The Flexibility Update!
You can now place your border wherever you want to create a individual player experience!

New Commands:

• /xpb toggle - Enable or disable the Worldborder
• /xpb center - Set the center to your current location

Fixed Bugs:

• The Worldborder doenst applied right when handling more than one level.
• Fixed Enchanting XP usage
• Fixed Anvil XP usage

Other:

• Removed unused code
• Added a new config "config.yml
• Code (YAML):

  xpborder:
    enabled : true
   

Thanks to "dice" for the suggestion!