Re: [webcomponents] Styling of elements where attachShadow(...) not allowed (#376)

I've seen https://github.com/domenic/html-as-custom-elements a long time ago already. It tries to tackle an issue fundamentally, which is definitely a bright happy (and far) future, but I have a feeling that most folks don't need it (at least initially).

What most of times people want to have is:
* input text/passwoord or textarea with pre-configured border, paddings, colors
* progress element's bar and value with customized colors (using existing even vendor-specific pseudo-elements)
* button that have predefined background, color, border

This is the reason I decided to boil down the whole issue to just styling alone. Strictly speaking it works like `style` attribute, but allows to use attributes selectors, pseudo-elements, pseudo-classes and other features like in regular CSS applied to this element (which is currently only doable with `html /deep/ element`).

Anytime in future when working with custom Shadow Roots on those elements is defined it will be possible to allow more than `<style>` and `<shadow>` elements without breaking backward compatibility. Let's assume UA Shadow Root as black box for now and just inherit as indivisible whole thing.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/issues/376#issuecomment-178056459