EDIT: This was the BaublesMod overlay. Customizable with NUM9. Sorry for the improper issue post
Whilst playing RLCraft I've come across a bug which I havent seen before. The belt icon which I placed in my baubles belt slot shows up on my screen in game (see screenshot)

I have no idea what mod could possibly cause that. I do know I never experienced that in development...

Is it persistent or does it go away after restarting the game?