[rlnorthcutt]

This is a decent fallback, but it really doesn't solve the underlying problem. The whole point of web components is the ability to encapsulate and reuse your work... and _specifically_ to extend the HTML tag library.

The fact that you need JS to load/run to parse your custom web component is an issue. But, the solution is to allow users to cache these components or add them to the browser itself.

Ideally, <user-avatar> should be available without JS just like <img> is. Imagine a world where we have this capability - a large library of reusable components that can be used as easily as native HTML. This is the vision, is it not?