this morning I switched to 2.3 M5 and use the actual amazonechocontrol binding.
(Raspberry pi 3 with openhabian - latest version)
When I open
http://192.168.178.50:8080/amazonechocontrol/
and then open the amazon account I get a lot of rubbish:
in Paper UI I have put the correct user / password, but see that alexa.amazon.de is not available (in reality it is though):
Anyone else with this issue?