Squids do not maintain horizontal inertia on land and do not maintain vertical inertia in water. This issue is server-side, so it causes massive desync, even in singleplayer worlds.
Steps to reproduce:
Hit squids with high-knockback attacks
Push squids on low friction surfaces
Drop squids into the water from a very high place
Put squids in bubble columns
Here's a video demonstrating the issues: https://youtu.be/9-COs5CHL18
Linked issues
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We're tracking this issue in MC-89883, so this ticket is being resolved and linked as a duplicate.
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