I have this strange issue. I have an iiyama 28" 4k screen along with an old samsung 22" 1600x1050 screen. When I use only the 4k screen I have black borders around embedded videos on many websites but when I expand my desktop to the other monitor the problem disappears. The strange thing also is that those black borders appear only on Chrome browser, but they do not appear when more than 1 screen is used. Please help.