The shadowrootmode attribute on <template> is about to be standardized

[mfreed7]

MDN URL

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/template

What specific section or headline is this issue about?

Attributes

What information was incorrect, unhelpful, or incomplete?

See whatwg/html#5465 which is going to land soon. When it does, the shadowrootmode attribute on the <template> element will be standardized.

The MDN page here: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/template#attributes looks like this:

In Chromium-based browsers, the <template> element also supports a non-standard shadowrootmode attribute, as part of an experimental "Declarative Shadow DOM" proposal. In supporting browsers, a <template> element with the shadowrootmode attribute is detected by the HTML parser and immediately applied as the shadow root of its parent element. shadowrootmode can take a value of open or closed; these are equivalent to the open and closed values of the Element.attachShadow() mode option.

That should be updated to remove the "Chromium-based browsers" language, etc., and refer to the spec.

What did you expect to see?

See above.

Do you have any supporting links, references, or citations?

See above.

Do you have anything more you want to share?

No response

MDN metadata

Page report details

• Folder: en-us/web/html/element/template
• MDN URL: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/template
• GitHub URL: https://github.com/mdn/content/blob/main/files/en-us/web/html/element/template/index.md
• Last commit: cefb028
• Document last modified: 2023-08-17T03:58:28.000Z

[Rumyra]

Thanks for raising the issue @mfreed7 - do you have any browser implementation bugs?

[mfreed7]

Thanks for raising the issue @mfreed7 - do you have any browser implementation bugs?

Sure!

• https://crbug.com/1379513
• https://bugzilla.mozilla.org/show_bug.cgi?id=1712140
• https://bugs.webkit.org/show_bug.cgi?id=249513

[pepelsbey]

FYI, there’s a task documenting shadowrootmode attribute for the upcoming Firefox 122 release (behind the flag for now, but will be enabled by default in 123).

[pepelsbey]

The shadowrootmode attribute has been properly documented in #31490

See https://developer.mozilla.org/en-US/docs/Web/HTML/Element/template#attributes