Information

Minecraft version: 1.21
Modloader: Forge / Fabric
Forge version: Fabric loader version: 0.16.0
Environment: Singleplayer

Mod name: Advancement Screenshot
Mod version: 4.8

Description

FPS drops to 20 when holding up a shield. I get 240 FPS (on average), but the moment I hold a shield (with the mod active), it goes all the way down to 20 (stable), like, exactly 20

That's very strange. And if you remove Advancement Screenshot, this doesn't happen?

yes, it doesn't happen when the mod is removed

That's very strange. And if you remove Advancement Screenshot, this doesn't happen?

And if you reinstall the mod, it happens again? Just making sure.

Spoke too soon, it looks like another mod was causing the issue, I just didn't consider it ✌️

That was my guess, as I wouldn't understand why it would've done that. But thanks for confirming, and giving the mod a try!