[Bug - Neoforge 1.21.1 - Curios 9.2.3] Curios in extra slot pop out.

[foxy52]

I have a curios that gives extra back slot (+3). I wear that, a backpack and another curios in those back slots. Whenever I log in or /reload, the backpack and the other curios pop into my inventory. Only the curios that gives extra back slot remains in the main back slot. I didn't happen in the previous version (9.2.2). Only happen since I updated to Curios 9.2.3. I have other curios that give slots too but only the back one having problem.

[TheIllusiveC4]

What item exactly is the curio that gives extra back slots and what mod is it from?