[webcomponents] Unclear regarding Shadow boundary-piercing combinators (#357)

So I'm a bit lost and I'd like your help to clear up something that confuses me:

In the f2f meeting in April there's been some disagreement regarding the Shadow boundary-piercing combinators (`/deep/', `>>>`, `::shadow') and [Chrome](https://www.chromestatus.com/features/6750456638341120) talks about them as deprecated.

What confuses me is to see them mentioned in the Shadow DOM Spec:

> The editor's draft of CSS Scoping specification [css-scoping-1] defines the selectors which are related to Shadow DOM. Specifically, it defines the following selectors related to Shadow DOM:
>
> ::shadow pseudo element
> /deep/ combinator, which was replaced with a >>> combinator (or shadow piercing descendant combinator)

Then again the cited CSS-Scoping spec states "It’s been suggested to remove this feature." about `::shadow` and "It’s currently disputed whether this combinator should exist." for `>>>`.

So it looks like it's possibly going to be removed, but the Shadow DOM spec doesn't say so.
So, shall I make a PR to clarify this issue in the Shadow DOM or is it just me who got puzzled by this?

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/issues/357