Slimes riding a boat or a chest boat do not render their outer layer of their entity model that is within the boat. As far as I've tested this is with every boat/chest boat type. This also seems to mainly affect the "small" slime type. There might be a chance it does affect the other sizes for the portions of those that are within the boat when they're riding it.
MCPE-153434
Slime outer-texture doesn't render within boats/chest boats
Resolved
Duplicate
1
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We're tracking this issue in MCPE-131451, so this ticket is being resolved and linked as a duplicate.
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