I get this all the time. I’m not actually alt tabbing, I’m not on windows I’m on Arch Linux and Hyprland and I switch between workspaces.
I haven’t had this happen to me at all my first day playing this game, but it happens all the time now I’m at the Nameless pass.
For some raisin I can’t even select the Items I want using wasd.
Spots that get selected feel kinda random it happens both in inventory and looting items. When looting, just closing and opening the loot window at least shows the first item in the pile highlighted.