Shadow ghost 2020?

So, recently, I was looking out of a window late at night at a scene illuminated only by street lamps. I noticed, to my surprise, a very dark figure moving along the pavement opposite. It did not look quite human. I was mystified and somewhat disturbed by what I saw and soon wondered if it could be a shadow ghost. It was entirely featureless. Then the figure vanished!

After a few seconds I realised what had happened. It was a cold night and the window was partially misted up. But there ‘holes’ in the misting that looked black. This was because the light in the room was off. As I approached the window it looked as though one of the ‘holes’ moved relative to the street scene behind. It gave the impression of a dark object moving through the scene behind. Because of its shape and position on the distant pavement it gave an impression of a human figure walking or, at least, floating along.

To anyone who thinks this observation sounds unlikely I can only say I thought it a genuine dark figure at the time. Indeed, I involuntarily reacted to it with a feeling of slight alarm. So clearly the unconscious part of my brain thought it was a real, slightly menacing, human figure. That is not the reaction you would expect to something that was recognizably innocuous. It was, of course, a misperception which is a common cause of ghost sightings. Without the peculiar lighting (a misted window illuminated by external street lights) I doubt it would ever have occurred.