When switching to a loaded crossbow, your main hand (or whatever item you are holding) lowers down, and the crossbow raises up afterwards. However that is not the case with the off hand, as it just pops in and out of the screen like in my attachment. This does not affect boats however, and I tried to simulate how it would have worked.
Thank you for your report!
We're actually already tracking this issue in MC-149860, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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