The bug
If you have a trident with the Riptide enchantment, and you throw it to fly with it, the "flight" will be cut short if you log out and log back in.
To reproduce
Obtain a trident enchanted with the Riptide enchantment
Stand in water
Throw the trident
Exit the world
Re-enter the world
Observed behavior
The velocity of the player is not anymore as it was before the world was exited.
Expected behavior
The velocity of the player would match what it was before the world was exited.
Related issues
Attachments
Comments


Confirmed for 1.13.1.

Affects 20w29a
Can confirm in 21w05b.
Can confirm in 21w06a. This can be easily reproduced with high levels of the riptide enchantment. I used the following command to reproduce:
/give @s minecraft:trident{Enchantments:[{id:"riptide",lvl:10}]}
Can confirm in 1.16.5 and 21w08b.
Can confirm in 21w16a.
Can confirm in 1.17.
Can confirm in 1.17.1. Video attached.
Can confirm this behavior in 1.18 Pre-release 1. Here are some extra details regarding this problem.
The Bug:
The momentum gained from the riptide enchantment effect is lost upon rejoining worlds.
Steps to Reproduce:
Enter a singleplayer world and give yourself a trident that's enchanted with a high level of riptide.
/give @s minecraft:trident{Enchantments:[{id:"minecraft:riptide",lvl:10}]}
Enter some water, throw the riptide trident and quickly exit the world.
Rejoin the same world and take note as to whether or not the momentum gained from the riptide enchantment effect is lost upon rejoining worlds.
Observed Behavior:
The momentum gained from the riptide enchantment effect is lost upon rejoining worlds.
Expected Behavior:
The momentum gained from the riptide enchantment effect would be retained upon rejoining worlds.
Can confirm in 1.19.

Actually, player's speed isn't saved by any means when quit and relogged.