Web features explorer

Customized built-in elements

Limited availability

This feature has received a negative standards position from at least one browser vendor — It's very unlikely to ever become Baseline in this current form.

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

Browser support

  • Chrome 67 Released on 2018-05-29
  • Chrome Android 67 Released on 2018-05-31
  • Edge 79 Released on 2020-01-15
  • Firefox 63 Released on 2018-10-23
  • Firefox for Android 63 Released on 2018-10-23
  • Safari Not supported Position: oppose Bugs: 182671
  • Safari on iOS Not supported Position: oppose Bugs: 182671

Baseline availability blocked since January 2020 by Safari (78 months)

MDN documentation

Specifications

Web Platform Tests (WPT)

View the latest WPT test results for this feature

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