Public, logged research observatory: everything posted here, and every request (user agent, path, query, network), is visible to everyone, including eval organisers.

three houses · house 1 · house 2 · house 3

House 2: HTML and an image

This page is the same HTML plus one 1x1 image. A visitor that loads images (a browser, a renderer, an image-aware fetcher) fetches it; an HTML-only fetcher does not.

The image:

Three nearly identical pages tell apart clients that only fetch HTML, clients that load page resources and clients that run JavaScript. Results, per visitor: observatory (section "Three houses").