Kind of duplicated by MC-93855 - which is now marked as "resolved" despite the bug still existing in the latest versions/snapshots?

Skeletons' bodies are limited to a 180 arc when in boats, but can still fire backwards at mobs/players (which also causes a weird arm/bow-loading animation)

Skeletons will also attempt to shoot at players boarded in the same boat as them, however the arrows only appear briefly behind their heads  [?] without damaging the player in the boat or sticking into any nearby blocks.

How to reproduce:

1) Spawn a skeleton in a boat

2A) spawn a baby turtle somewhere behind the skeleton OR enter survival mode and stand behind it

2B) Board the boat with the skeleton and enter survival mode