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web api instance property

HTMLElement: inert property

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The HTMLElement property inert reflects the value of the element’s inert attribute. It is a boolean value that, when present, makes the browser “ignore” user input events for the element, including focus events and events from assistive technologies. The browser may also ignore page search and text selection in the element. This can be useful when building UIs such as modals where you would want to “trap” the focus inside the modal when it’s visible.

Note that if the inert attribute is unspecified, the element itself may still inherit inertness from its parent. However, that inherited inertness is not reflected by this property’s value. Explicitly setting the property to false cannot revert inertness inherited from the parent.

Value

A Boolean which is true if the element is inert; otherwise, the value is false.

Examples

HTML

<div>
  <label for="button1">Button 1</label>
  <button id="button1">I am not inert</button>
</div>
<div inert>
  <label for="button2">Button 2</label>
  <button id="button2">I am inert</button>
</div>

CSS

[inert] > * {
  opacity: 0.5;
}
Interactive exampleOpen the canonical MDN source to run this embedded demo.

[!NOTE] This attribute, by itself, will not cause any visual change to the content as displayed in the browser. In the example above, CSS has been applied so that any direct descendant of an element with the inert attribute is rendered semi-opaque.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also