Have been meaning to post about this for a while but finally getting around to it - on macOS, the address for the current device is missing from the menu bar dropdown most of the time, so you have to go elsewhere to get the Tailscale IP of that machine. See screenshot below.
Most of the time, the menubar dropdown looks like this. Sometimes, when running Tailscale for the first time after updating to a new version, My Device will show up again, but after rebooting or quitting / restarting, it’s gone again.
I’m currently running the standalone app version of Tailscale, but I previously used the App Store version, and the same thing happens with both versions.