A glitch in the Matrix is the term for an event or occurrence that looks faked and like our reality is nothing more than a computer simulation, filled with bugs that make the laws of physics, space, and time act in unexpected way. It’s named for a sci-fi movies series about artificial intelligences who trap humanity in a computer simulation. The freedom fighter humans refer to "a glitch in the Matrix" to describe times when the malevolent artificial intelligence “reprograms” something around our heroes in order to try to trick and capture them.
For this woman, her glitch happened during the recent blizzard that plagued much of the country over the Christmas weekend. She was attempting to film the snowfall outside her door, but got an unexpected glitch instead.
In the video, she is holding her door open against the storm, filming out into the darkness. In the light (either from her camera or over the door) the snow is falling furiously—blowing in every direction—against a black background. The only details that can be seen are a blurry bit of tree and the house across the street.
Then, suddenly the image changes. Instead, what you see is a clear view of the yard and street, with a light colored sky, and no snow in sight.
What’s going on? Did the sky turn off?
What we’re probably seeing here is an artifact of her phone camera, most of which these days have advanced “night features” that will make out large objects in dim lighting (like the tree and the houses across the street) instead of having a light bounce off the closer snowflakes, as it did when the flash light or door light was on. Think about the way a camera flash might white out close by objects, vs the detail that can be obtained when the flash is off. Same principle.
Of course, that doesn’t mean we aren’t living in a simulation anyway…