Thanks Kostya.
Yes, it works now in 1.17.0-1212-dev.
I found a problem... After a password change I get a "OATH2 returned something strange" (or something like that) and I cannot re-authorize.
There is no option for updating authentication, and even in the account settings I cannot do anything (any attempt to update account results in the same 'something strange' message box, with no way to invoke authentication again.
I manage to work it around by adding the 2nd account for the same mailbox. It allowed me to go through authentication again, and unblocked the 1st account as well.
As a consequence, I cannot reproduce the problem and collect logs for it :-(.