The biggest weirdness about it was that it was essentially a parser macro, not an element. That is, at parse time, it expanded into a form/label/hr/input set of

The biggest weirdness about it was that it was essentially a parser macro, not an element. That is, at parse time, it expanded into a form/label/hr/input set of elements into the token stream. Super-bizzare. See the removal patch at https://github.com/whatwg/html/commit/5c44abc734eb483f9a7ec79da5844d2fe63d9c3b https://github.com/whatwg/html/commit/5c44abc734eb483f9a7ec7....