Default page for site root not imported

All my default pages import, except for the default page of the plone site root. I notice in `defaultpages.json` that there is an object with UID `plone_site_root`, but this object ID does not appear in the `content.json` file (the actual plone site root has a concrete UID.

It does not look like the defaultpages routine that looks for the site root actually links the default page with the site root.

What gives?

Start by comparing defaultpages.json with content.json, focusing on the object with UID plone_site_root and the concrete UID of the actual Plone site root. Trace the defaultpages routine that looks for the site root and determine why it does not link the default page; done means the site-root default page is imported and linked correctly.

Written by the indexing model from the issue text.