and you can follow that back to the forum if you want to help characterize this for investigation.
is the known behavior for regular (without --no-hosted-server TrayIcon. Link to issue is there.
Error seems quite clear. It needs a password. Empty one isn’t enough.
The freeze in second test might be the “appears to hang” (though you did a double-click instead).
Third test (“same as second”) seems to add logging. Maybe developer can comment on the logs.
Have you looked in the event logs in Windows Application log? Sometimes info is available there.
What is the status with the service? You seem to have a password, so direct browse should work.
In some tests, TrayIcon appeared to interact with Duplicati as expected. Is only issue initial open?