On the bright side if a DM lets you hide in front of a bugbear who is looking directly at you without even disadvantage then you're getting away with murder. Normally if BG3 makes you take a stealth check it's in a situation a DM would have you auto fail.
The instances I'm referring to are ones where the target creature HAS NEVER even seen the PC, or the PC has ran to an adjacent area with cover. I've even been caught stealing with Greater invisibility and the Hidden condition.
Were you in "hiding" state when you stole stuff?
I find that steel watchers immediately turn around when I don't crouch when steal stuff even when invisible, but otherwise don't react when I'm invis.
Hopefully this is formatted right (on mobile).
I got into a fight with some Flaming Fist folks. The bodies were highlighting red, and I didn’t want to “steal”. So I broke line of sight with all NPCs, cast greater invisibility on myself, hid, then stealth walked back to the bodies by myself, and the moment I touched the body I got stopped by a new flaming fist accusing me of theft.