If you have a command block with nbt data and place it down, then paste in a new command then change the minecraft window it will revert the command.
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Sonicwave
MC-84559
Editing a command block and then changing window resets command block.
Resolved
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0
Sonicwave
migrated
(Unassigned)
Unconfirmed
Minecraft 15w31c
Retrieved
Duplicate of MC-258. If you have not, please search before reporting issues to see if your issue has been reported already.