The restoring a backup *will* restore the passwords too, if you take the FULL backup instead of the DB backup. How to take the FULL backup? There is no GUI button given for it, but API on method GET is given which does it.
So in your browser URL, provide : http://<WFA>/rest/backups?full=true
Provide the credentials of 'Admin' when asked.
you will get full backup, with passwords.
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