[SOGo] Changing default user settings

[Federico J]

Hello, new SOGo user here!I've just deployed SOGo and would like to set a 
different default value for user settings which are in Preferences .
For example, for new users the default value for "Compose messages in" is 
"HTML", I'd like the default for all users to be "Plain text".Or to enable 
desktop notifications by default.
For what I read these settings are not set on sogo.conf.
Is there any way to do this?Thank you!!