I tried testing FreeNAS in a VM. I did see that the Duplicati package is configured with a web UI password by default (set to ‘duplicati’), and it did not display the ‘first run setup’ dialog (which I think is appropriate in this case, as it is with docker containers).
I confirmed what @voodooutt saw. When I restart the plugin, the UI password reverts to the default.
@ts678 nailed it - the plugin is setting a fixed password on the command line:
