You can’t use shears to stop kelp/whines from growing. This was added to Java Edition in Snapshot 21w37a:
Using shears on the tip of a Cave Vine, Twisting Vine, Weeping Wine or Kelp now causes it to stop growing
Steps to Reproduce:
Place kelp and these vines.
Get shears and try to use them on the tip of the kelp and the vines.
Observed Results:
It doesn’t work.
Expected Results:
You should be able to use shears to stop kelp/whines from growing.
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We're tracking this issue in MCPE-141497, so this ticket is being resolved and linked as a duplicate.
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