Homebridge v1.3 (tested with Beta 22) displays a warning for returning a "write response" value if the characteristic itself does not support it.
Example Warning:
[12.11.2020, 22:30:28] Received warning for the plugin 'homebridge-test' from the characteristic 'S2W2': SET handler returned write response value, though the characteristic doesn't support write response!
[12.11.2020, 22:30:28] SET handler returned write response value, though the characteristic doesn't support write response!
Homebridge v1.3 (tested with Beta 22) displays a warning for returning a "write response" value if the characteristic itself does not support it.
Example Warning: