TOC not shown on imported markdown with Astro Starlight

[securitykernel]

I am successfully using astro-remote to import remote markdown files with Astro's Starlight (thanks for that, its a great tool!), but the TOC is not populated for a remote markdown file. It only ever displays the one default entry Overview. Usually, the TOC is populated from the markdown's headings for local markdown files, but that does not seem the case for remote markdown imported with astro-remote.

Is this a missing feature or something that needs to be configured?