Discovered while testing MC-164001.
The bug
When a trident stops ascending and starts descending, it can appear to face straight down for a matter of frames while turning.
How to reproduce
Hook up a 21-tick repeater clock to an upward facing sticky piston with two slime blocks on top
Fire a trident into the top slime block
Activate the clock
Observe after a while
Expected results
Smooth trident rotation.
Actual results
For an instant at a time during its apex, it flicks into a position facing straight downwards.
Related issues
discovered while testing
Attachments
Comments

Are you able to attach a world file to allow for easier reproduction of this issue?

In 1.21.