When testing around with some slimeblock launchers i found out that when running over slime block that are being pushed upwards by a piston you dont get launched as you would when standing still. this is also a problem when walking and has broken tons of slimeblock entrances, launchers etc.
Bug Report Video
(Reason : file too large)
https://youtu.be/YYP4e5VKTMY
Related issues
Comments

Duplicate of MC-89043
Any movement cancels the slime block launch
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(But under 1block upwards motion)