HTMLTemplateElement: shadowRootCustomElementRegistry property

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

The shadowRootCustomElementRegistry property of the HTMLTemplateElement interface reflects the value of the shadowrootcustomelementregistry attribute of the associated <template> element.

Note: This property is not useful for developers, and is only documented for completeness. If a <template> element is used to declaratively create a ShadowRoot, then this object and property do not exist. Otherwise, if an HTMLTemplateElement is created, the value of this property is irrelevant because the object is not a shadow root and cannot subsequently be changed to a shadow root.

Value

A string that reflects the shadowrootcustomelementregistry attribute of the associated <template> element.

Specifications

Specification
HTML
# dom-template-shadowrootcustomelementregistry

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
shadowRootCustomElementRegistry
Chrome – Full support
Chrome 146 (Release date: 2026-03-10)
footnote Full support
Edge – Full support
Edge 146 (Release date: 2026-03-13)
footnote Full support
Firefox – No support
Firefox
footnote No support
Opera – Full support
Opera 130 (Release date: 2026-04-08)
footnote Full support
Safari – Full support
Safari 26 (Release date: 2025-09-15)
footnote Full support
Chrome Android – Full support
Chrome Android 146 (Release date: 2026-03-10)
footnote Full support
Firefox for Android – No support
Firefox for Android
footnote No support
Opera Android – Full support
Opera Android 97 (Release date: 2026-04-16)
footnote Full support
Safari on iOS – Full support
Safari on iOS 26 (Release date: 2025-09-15)
footnote Full support
Samsung Internet – No support
Samsung Internet
footnote No support
WebView Android – Full support
WebView Android 146 (Release date: 2026-03-10)
footnote Full support
WebView on iOS – Full support
WebView on iOS 26 (Release date: 2025-09-15)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
No support
No support

See also