You Look Like You’ve Seen a Ghost
When you’re playing a video game, it’s common to make characters do funny things like walk through walls or fly through midair. But what if you felt like you were watching a video game live play… with real human beings? If you see a person leave a place, you don’t expect to rewatch that scene in real-time.

But what the original poster of this story describes is like watching two video game characters walk through digital walls at the push of a button, with no need for the normal human constraints of re-entering a place and then leaving again. Was this OP having a super vivid waking dream… or did they find proof that our reality is a simulation?