First off, if I could post this issue on GitHub directly I would have. The extra verify device step now directly mails to my hotmail address which in turn now also requires an extra verification step. I have to give MicroSoft another e-mail or cellnumber to get in. All without opt-out and "for my security".
The issue: The response from the rpc-service using method "torrent-get" now contains values for all fields in the request, even fields that Transmission does not know. For fields that transmission does not know the value 0 (zero) is returned. The expected behavior (as it was) is that the unknown fields in the request are not present in the response at all.