Based on the concept of the attached video, when you look through the (in game) camera some minor environmental text/features change.
For Instance, in level 0 there’s the random piles of scattered pages and books. If you view them without the camera, a page might read “Nelson Mandela freed from prison”, but if you look at it through the camera it reads “Nelson Mandela dies in prison”.
That’s a very basic example but I think the idea would be neat, especially if paired with common supposed “Mandela effects”.