''locking as a duplicate of [/questions/1152512]'' Hello, I have a problem: when I watch videos there are horizontal lines that appear on the black sidebars of the video and they flicker a lot. They only appear on full screen mode and when the video is not paused. They have the same colour as the pixel that is ajecant to the sidebar at that moment. I have tried multiple websites, they all have this problem. Thank you for your help.