Yup, this is why the ArchiveBox browser extension sends URLs to a separate server for archiving with an isolated burner profile.

I should write a full article on the security implications at some point, there aren't many good top-down explanations of why this is a hard problem.

I know it’s a lot of work but this would be great and it may give readers a deeper understanding into security in general.

How does it save pages that are only available when you are logged in such as social networking pages?

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).

That’s a very cool solution- gives the user explicit control