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Showing 2 of 2 features

Limited Availability

2 features
• In Progress / Not Yet Baseline

Customized built-in elements are HTML elements that extend built-in elements using the is attribute, to add new behaviors that you define.

Chrome 67
Firefox 63
Safari
Edge 79
Status: Incomplete cross-engine support

The CustomElementRegistry() constructor creates a new custom element registry that's separate from the global window.customElements registry. Creating more than one registry is useful for multiple custom elements that have the same tag name to coexist.

Chrome 146
Firefox
Safari 26
Edge 146
Status: Incomplete cross-engine support