[Phemist]

Remember when the :visited modifier on an <a> tag was a thing?

https://developer.mozilla.org/en-US/docs/Web/CSS/:visited

And third-party tracking websites would load their websites up with a bunch of hidden anchors and then through JS read the visited state of these websites to get an accurate fix on a person's identity, or at least of their (relevant) browser history?

And how this modifier was removed ASAP once people realised its abuse potential?

Basically Google thought this was a good idea after all, and is bringing a "coarse-grained" version of it back.