See phab:T118540 ("Allow adding pages to the watchlists of new accounts, either by default or during manual account creation") for details.
I think this might fit, into the idea behind this extension?
NewUserActions is a WIP extension to complement NewUserMessage and execute further actions when a new user is created.
This talk page can host discussions about the extension documentation, and in some extent, about bugs, feature requests and support requests.
We would prefer bugs and feature requests to be filled on Phabricator for better tracking.
See phab:T118540 ("Allow adding pages to the watchlists of new accounts, either by default or during manual account creation") for details.
I think this might fit, into the idea behind this extension?
Yes, I imagine, as the extension has indeed the goal to allow onboarding workflows. For example, the first use case is the @Guillom's suggestion to allow to create an user page with a preloaded content for officewiki.