When casting a fishing rod into water the bobber floats too low. For example, in other versions of the game when the fishing rod is cast on water with a tripwire above it, the bobber triggers the wire just by floating (And when a fish is hooked it sinks below). However this isn't the case. The bobber is below the wire and nothing is triggered.
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-19554.
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