Hey !

I use Hats Mod (10.3.2) on 1.16.5 Forge (36.2.4) server and I see a stange thing.

I have some villagers and cats in a village.
I changed their hats with the hat launcher, and after random time, the mob goes back to its original hat.

Sorry for the late response to this. I suspect this might have been because of issues with Forge/Hats loading the Hat capability attached to mobs. Is this still a present issue the last time you played with Hats?

Ahah, I'm sorry but I've updated the server for 1.18.2 last year and I removed Hats Mod from the mods list due to the missing of 1.18 release, so I can't tell you if the issue still present again but I remember the last time I've played with it, the I encounter the issue.