optionalServices property
A list of service UUIDS that a device may have or may not have.
NOTE:* You NEED to define a service in either the filters or optionalServices if you want to be able to communicate with a characteristic in it.
NOTE: Some services are on a block list, and are thus not available. The complete blocklist can be found here: https://github.com/WebBluetoothCG/registries/blob/master/gatt_blocklist.txt
Implementation
external List<String> get optionalServices;