It looks like there is a problem in Omega firmware.
Running device-client -v results in this repeating over and over again.
> Restarting connection (restart #3) ...
>> Starting device client
>> Starting listening...
'> Sending request to 'ds.onion.io/5a4af900-e5e4-4c2e-9787-e0d041f5f312/listen?key=LBHkOoFxEUXkGYjlwB4eguTwyrCild4OddKhBC4ro2dkY1PiqDEnsTkXIo2xgemd
Error: curl_easy_perform: Illegal characters found in URL (3)
>> Completed GET
> Connection lost!
Device id and device key in the web request are correct and going to that link in browser actually makes the device appear online. (I changed the id and key in the code above so nobody plays with my device.)
Which means problem is in device-client.