The whole whatwg ES3.1/5 saga was dealing with the specs saying what they wanted the world to be (which they did badly and incompletely, and frequently in direc

The whole whatwg ES3.1/5 saga was dealing with the specs saying what they wanted the world to be (which they did badly and incompletely, and frequently in direct contradiction with) and what browsers needed to do (the “quirks”). The spec as produced by whatwg and the browser vendors actually matched reality, didn’t have ambiguity (or rather any ambiguity that was missed is considered a spec bug/error) and could actually be used to make a browser.