document.querySelector first got wide browser support and started to end jQuery’s ubiquity? It finally gave us a way to do natively what jQuery had been providing for years: easy selection of DOM elements. I believe the same is about to happen to frontend frameworks like Angular and React.
The article goes on to give a good technical overview of custom elements, templates, and the Shadow DOM, but I was surprised to see it making reference to the
is syntax for extending existing HTML elements—I’m pretty sure that that is, sadly, dead in the water.