Popover API

Supported Per Spec Updated: Jan 13, 2026

A web API that enables promoting elements to the top layer, escaping containing blocks and superseding z-index layering, solving a common CSS pain point.

Baseline:
Newly
Functional:
Progressing
Usage:
Cross-Context

Popover works within shadow DOM contexts, both declaratively and via scripting. The trigger and the content must exist in the same context, though the content may be the light DOM of another component as long as its ID is unique.

Ranked progressing due to focus behavior inconsistencies: Firefox and Safari fail tests for focus handling inside shadow DOM popovers. Core popover functionality and shadow host focus delegation work correctly across all browsers.

Web Platform Test
Chrome 147
Edge 146
Firefox 149
Safari 26.4
Focus behavior of popover elements inside shadow DOM
pass
pass
fail
fail
WPT sources: popover-shadow-dom, popover-focus-inside-shadow-dom, popover-shadowhost-focus