Pistons can have two heads at a time and can retain one of its heads

We do not have enough information to find the cause of this issue.

Please record a video of this happening with the debug screen enabled (F3) and attach it to this report.
If you are on Windows, you can use Windows+Alt+R to open a built-in app for recording game footage.
If you are on Mac (Mojave or later), you can use Shift+Command+5 to open a built-in app for recording your screen.
In case you don't have a program to record videos, we recommend using the free recording software OBS.
In case the resulting video file is too large to be uploaded to the bug tracker directly, please upload it elsewhere (e.g. as unlisted video on YouTube) and link to it here.

_{This issue is being temporarily closed as Awaiting Response. Once the requested information has been delivered, the report will be reopened automatically.}

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Thank you for your report!
However, this issue is Incomplete.

Your report does not contain enough information. As such, we're unable to understand or reproduce the problem.

You are welcome to create a new ticket about your issue with more detailed information. In case of a game crash, be sure to attach the crash report from [minecraft/crash-reports/crash-<DATE>-client.txt|https://minecrafthopper.net/help/finding-minecraft-data-folder/].
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F3 just darkens the screen, so I must press Fn+F3

Relates to MC-59564.

This is now a duplicate of MC-254385