You set up a chrome profile for archiving that's logged into all the sites you want to save. I recommend using burner accounts dedicated to archiving, so you'd

You set up a chrome profile for archiving that's logged into all the sites you want to save. I recommend using burner accounts dedicated to archiving, so you'd have to add them to any private pages/groups you want to archive. It is possible to use your main account for archiving but there are security risks (you cant share the snapshots without leaking session headers).