Infinite scroll does not work for sorting content by anything other than chronologically

The current implementation of infinite scroll does not allow results to be sorted by anything other than reverse chronologically.

This is particularly a problem with search pages. By default WP sorts search results reverse chronologically, but this is not the best way to sort for many use cases. O2 should either allow infinite scroll of search results, or it should have support for paging results. Currently when we replace search with a different backend the first page of search results works, and then no results are returned when the user tries to scroll.

Start by tracing the infinite-scroll implementation for search pages and how it requests subsequent results when a non-chronological sort or replacement backend is used. Review the existing search result paging behavior; done means search results continue loading after the first page under alternate sorting, or paging results is supported instead.

Written by the indexing model from the issue text.