Can't see enemy vision zones! can't stealth without them

The rest of the game seems to be working fine, but I can never see the red/white circles around the enemies that would allow me to stealth past them. There’s nothing in my setting or controls…what do I do?

Hmm that’s weird! Are you on PC? Normal difficulty? If you happen to have a screenshot or video we’d love to see it. And what are your computer’s specs? Thanks!