The bug
If no targets are near the premise of near the piglin brutes, they rapidly raise their arms and lower them.
To reproduce
Spawn a piglin brute
Set gamemode to survival and wait for the piglin brute to chase after you
Quickly press F3 + N to go to spectator mode
→ ❌ The piglin brute then raises its arms up and down in a freaky way and then stops
Related issues
relates to
Attachments
Comments

[media]
I can confirm in 20w46a.
Can confirm in 21w03a.
Can confirm in 21w05a.