Today you can run the web version of VSCode "serverless" via yarn web. In this model we add a single extension into the staticExtensions property to run it inside the web worker and that one registers a file system provider:

This is an in-memory provider and the idea would be to use a GH provider, maybe depending on a query parameter in the URL. This would only provide a readonly view on a repository, but that is fine to begin with. We could expand the capabilities depending on available API, e.g. allowing to search.

My understanding is that Eric you already wrote a file system provider once for GH that we could maybe use here.