Airplay on High Sierra
I have recently purchased as new MacBook Pro (MacBook Pro (13-inch, 2017, Two Thunderbolt 3 ports)) and updated the OS to High Sierra.
Since the update the Airplay icon is no longer available in the menu bar, to allow me to stream/display to my Apple TV. I have checked all settings which could affect airplay like "Show mirroring options in menu bar when available" from within the display and also firewall settings as also read about.
The Apple TV is a 2nd generation and is up to date in terms of software. Airplay to the same Apple TV is fine with my Iphone/Ipad but cannot get it to work with the new MacBook. (it also works fine with my 2014 iMac)
I also have Sky Q, which supports Airplay, so at the very least I would expect the option to stream music through the Sky Q boxes.
MacBook Pro, macOS High Sierra (10.13), null