The item was unable to select when on a boat.
If i held nothing but i want to select something while on a boat, it selected but it didn't show up. Sometimes it refuses to select the item on the hotbar.
An example is i hold a horn and i want to select a fishing rod. It will not select or selected but using the same horn
The only way i would be able to use an item while on a boat is i leave the boat select an item on the hotbar and go back in.
Thank you for your report!
We're tracking this issue in MCPE-156814, so this ticket is being resolved and linked as a duplicate.
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