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Screen mirroring technology include Apple AirPlay 2 and Miracast. Please be mindful that in order to use AirPlay 2 the following system requirements must be met: iPhone, iPad, or iPod touch with iOS 11.4 or later; Apple TV 4K or Apple TV HD with tvOS 11.4 or later1; HomePod with iOS 11.4 or later; Mac with either iTunes 12.8 or later or macOS Catalina. ^Daphane
It at first didn't pop up on my Samsung s10 but did after power cycle and connecting to the wifi and with a cable on the TV.