Chrome-signing protocol dose not matter... so, good bye vivaldi.
Hm. There is a lot of useful extensions based on chromium-signin protocol. Without it... extensions for Google's services - are not available. All extensions for synchronize my android with browser - are not available. All services, who use fast authentication with Google account - are not available. Frankly, faced with 'these limitations, I had to return to the firefox. Vivaldi cant provide me a tool for solving my daily tasks to which I was accustomed. You sad " the issue not a priority". So, see you later, Vivaldi. Grow up, kid. p.s. Sorry for my english.
Yes, the Google Services are not working yet completely.
May be you come back sometimes and recheck newer Vivaldis. Bye.