very simple php script to change mail passwords on a uberspace via web
Save index.php to a Uberspace web document folder where you have set up your mailboxes. This can be for example ~/html or a subfolder or an alternative docroot for a specific subdomain.
Now point your browser to the scriptfile and you will be able to set a new mailbox password by authenticating with the current mailbox password.
ATTENTION: This is a simple sript and not thoroughly tested, if you want to use it, you may want to put it behind additional security barrier like http auth.