ShadowRoot.activeElement

The activeElement read-only property of the ShadowRoot interface returns the element within the shadow tree that has focus.

Value

The Element which currently has focus, or null if there is no focused element.

let customElem = document.querySelector('my-shadow-dom-element');
let shadow = customElem.shadowRoot;
let focusedElem = shadow.activeElement;

Specification
HTML Standard # dom-documentorshadowroot-activeelement-dev

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`activeElement`	53	79	63	No	40	10.1	53	53	63	41	10.3	6.0