Thread:Project:Support desk/Changing preferences for all new and existing users

Is it possible to set a preferences flag for all existing users and also default it to "on" for all new users that will be created?

I'm particularly interested in "Auto-Number Headings".

I looked through the extensions and found nothing current that can do this, and there doesn't seem to be a way to change another user's preferences from any of the Special pages that I could see.

Running mediawiki 1.17.0.

Thanks!