When armored wolves took damage from warden's sonic boom, the durability of the armor seems to decrease from sound cues.
But when the armor supposed to break, it still appear attached to the wolf.
Recorded when this happens: https://youtu.be/zNDi-c6yrjA
Subtitle seems to say "Wolf armor breaks" but the armor is still visually there.
can no longer reproduce in 1.21 Pre-release 2.
It was fixed somewhere between 1.21 snapshots, but I can't find any mention of it in accumulated 1.21 fixes in the wiki https://minecraft.wiki/w/Java_Edition_1.21#Fixes