Using a piston and a redstone lamp you can duplicate pistons
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Please create a new ticket which provides additional information, so we can better help with your problem:
Was this a single player or multi-player/lan game?
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Try it out using this setup for proof.
No crash singleplayer not corrected for both
Please do not mark issues as private, unless your bug report is a security issue containing information that may compromise your server/client.
I made it private since is was flagged as incomplete (Sorry I am new here and I should have read the rules better.)