It's 2021 and we still can't define custom tags in html (without js) :

<template tag="test"><h1>works</h1></template> <test/>

is= is dead, and Safari had good reasons for it. On mobile, so can't quickly find the rationale.

But it's the same rationale IIRC why built-in components are not extensible (even if this was one of the original promises): the browser has no way of knowing about the actual behavior of the object, which leads to all kinds of mess inside the engine.

So many other parts had to be done in a specific manner or left out entirely to get committee consensus, yet this was written into the spec even though Apple has opposed it from the beginning.

The validity of Apple's reasoning makes it even stranger.

Yeah, the whole thing about Web Components is weird. And is getting increasingly weirder.

Quite recently Constructible Stylesheets were released in Chrome:

- because lit wanted them

- despite Firefox and Safari being against the state of the spec

- despite Safari clearly stating they are not going to implement the spec, ever (there was a trivially reproducible race condition in the spec)

The entire discussion here: https://github.com/WICG/construct-stylesheets/issues/45#issu...