Google has yet another search results interface test, this one is in the core web results snippets that add "on this page" buttons. It reminds me of the tags in the snippets and maybe it is a variation of them?
Here are screen shots from Sergey Alakov on Twitter of this test:
In the previous test, which I called "tags", it was not clickable. Here when you click it, it anchors you down to the appropriate part on the page it is linking to.
