ToggleEvent: oldState property

Baseline 2025
Newly available

Since January 2025, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.

The oldState read-only property of the ToggleEvent interface is a string representing the state the element is transitioning from.

Value

A string. Possible values are "open" (the popover is going from showing to hidden) or "closed" (the popover going from hidden to shown).

Examples

js
const popover = document.getElementById("mypopover");

// ...

popover.addEventListener("beforetoggle", (event) => {
  if (event.oldState === "open") {
    console.log("Popover is being hidden");
  } else {
    console.log("Popover is being shown");
  }
});

Specifications

Specification
HTML
# dom-toggleevent-oldstate

Browser compatibility

BCD tables only load in the browser

See also