Mobs don't take upwards knockback properly from melee and range attacks when not on ground
Can be replicated by:
Jumping before getting hit by an iron golem
Jumping during a ravager roar attack
Simply hitting a mob that is falling
Shooting a mob with snowballs continuously and slowly looking up as you bring it upwards via the default upwards knockback value
Thank you for your report!
However, this issue is Invalid.
You have posted a feature request or a suggestion. This site is for bug reports only. It is not clear from your report why we should expect mobs to gain vertical momentum from the actions you describe, so I take it you are just asking for a new feature.
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