Web Components

[annevk]

Raising this per suggestion from @dbaron in #59. I'm not really sure how to split this up since as per https://github.com/w3c/webcomponents/blob/gh-pages/README.md the situation is complicated.

• Shadow DOM: we're implementing "v1" and this is now part of the DOM and HTML standards. (Some parts ended up in CSS, UI Events, Touch Events.)
• Custom elements: we're implementing "v1" and this is now part of the DOM and HTML standards.
• HTML Templates: shipped and now part of the HTML standard.
• CSS changes: I'm not sure what the status is here.
• HTML Imports: this is now abandoned I think. We've opposed this in the past: https://hacks.mozilla.org/2014/12/mozilla-and-web-components/.

On top of that there's various new proposals which @smaug---- and I should know more about next week (there's a meeting). My thinking is that we'll open issues for those proposals, but that for the above (apart from the CSS bits) we don't really need anything.

[smaug----]

FWIW, we've shipped parts of HTML Templates.
https://bugzilla.mozilla.org/show_bug.cgi?id=1090513 is open

[annevk]

Minor update:

• We plan to implement the basics of https://drafts.csswg.org/css-shadow-parts/ for internal usage (see https://bugzilla.mozilla.org/show_bug.cgi?id=1505489)

[annevk]

Closing this per above. We'll file new issues as appropriate.

[smaug----]

We've shipped Shadow DOM and Custom Elements. Is there any reason to keep this open?

[dbaron]

We should document our positions in the table before closing issues.

[dbaron]

It seems like there are four pieces here:

• Shadow DOM - should we list this as important or something else?
• Custom elements - same?
• HTML Templates - same?
• HTML Imports: seems like we should list this as harmful based on the info above, but we'd need an explanation of why. @annevk, would you be able to write that?

It's also possible we need a position like acceptable for something that's past the prototyping stage but not important? If we had such a position, would we want to use it here?

[zcorpan]

I have split this into separate issues (see #1087):

• Custom elements #1092
• HTML Imports #1093
• Shadow trees (formerly known as Shadow DOM) #1094
• template element #1098