It's a small and rather cheap add-on but I think useful nonetheless.
The idea is to hide the backfacing or non-visible geometry to address the issue of Backface Culling not hiding mesh components in Edit mode (vertices, edges, faces).
It was mostly made with retopology with X-Ray mode in mind, but isn't limited to this use case.
The image shows a comparison between the built-in Backface culling and the Backface hiding from this add-on when doing retopology on top of a high-poly mesh with X-ray enabled on the low poly mesh.
More info and the add-on itself on Gitlab.