This reminds me of browser fingerprinting via CSS[0], which has come up quite a surprising amount of times. Sending the browser's width is a bit more convoluted

This reminds me of browser fingerprinting via CSS[0], which has come up quite a surprising amount of times. Sending the browser's width is a bit more convoluted though. From what I've seen, the popular (well, as popular as CSS-only fingerprinting is) method is to set a media query for each px value. When the user resizes the window, the new width is sent to the server. Obviously something like this would be generated code, not written by-hand. [0]: https://news.ycombinator.com/item?id=29794518 https://news.ycombinator.com/item?id=29794518