If you see a shift or a break in these vertical black and white stripes that forms a horizontal line across the screen, that means you have screen tearing. The visual artifact that looks like the edges of the stripes fail to line up occurs when a video or a 3d game is not in sync with the display's refresh rate.
Screen Tearing Example:
https://youtu.be/rg_0D96ZGSY

How to fix Nvidia horizontal lines tearing bug:
https://youtu.be/oYWer86A20s

How to fix screen tearing on Intel cards:
https://youtu.be/IJeX35wbZY4

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