AirDrop Missing in Finder on MacBook Air 2017
I'm using a new MacBook Air (13-inch 2017) with macOS Sierra 10.12.6.
Bluetooth & WiFi are enabled and I'm logged in with my Apple ID and I can use AirDrop to both send and receive files if I use the sharing menu from within an application (e.g., in Preview).
However, AirDrop is not shown as an option in the Finder. If I open the Finder preferences and go to the Sidebar tab, AirDrop is not listed as an option and I can't see the Finder's AirDrop screen in any window to set its preferences:
How do I get AirDrop to appear on my Mac in the Finder?
Thanks
MacBook Air, macOS Sierra (10.12.6), 13-inch 2017