The problem comes from the fact that even when we set a password, we don't get back a pair
(Account.archiveHasPassword, bool) in the account details.
Precisely from the daemon : RingserviceJNI.getAccountDetails(accountID) doesn't return a map where this tuple exists
Actually you can see that even when you change the password, the displayed text for the password changing button remains the same ("set") instead of "change".
So it has nothing to do with the backup but with the fact that we don't get any information if there is a password with the current account.