By locating the upwards facing sticky piston with the sideways facing the observer on it that moves a block with redstone dust under it that will move the piston, you are able to make an infinite loop of piston extension and retraction, with no redstone dust or observer ever appearing to be moved. Some people think it is a bug because it does not fit with the quasi-connectivity and 1-tick pulse from the observer that supposed to cause the piston to not retract the observer after extending.
The piston is able to be only stopped by damaging one of the components mentioned before or by updating it while it is extended. The redstone dust does not even need to be in the orientation where it should be able to move the piston. You can start this loop by either powering the piston or making the observer power the block.
Affects Version/s: 1.15.2, 20w12a
Fix Version/s: None
Confirmation Status: Confirmed
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