On every Minecraft version I have tested (1.12.2, 1.16.5, 1.18 (all releases), 1.19 (all releases), 1.20, (all releases), and 1,21 (all releases) I can commonly reproduce arrows bouncing off of flying entities as if they have damage immunity despite not taking damage or having any other lag. I have also had this happen to mobs on the ground however it is too rare of an occasion to catch on video.
Additionally, (while unsure if this is a related bug) snowballs when thrown while flying (usually diagonally) hit boxes will stutter and teleport around. I cannot figure out what causes it to start or to stop.
When i tried this bug with fabric and replay mod the arrows hit box was teleporting as well.
Environment
Any area with a flying entity (phantoms I found to be easiest for testing). Bug tested successfully on 3 different accounts across 4 computers.
Linked issues
duplicates 2
Attachments
Comments 4

Thank you for your report!
We're tracking this issue in MC-102732 and MC-298762, so this ticket is being resolved and linked as a duplicate.
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