Web platform features explorer

Observable

The when() method on a event target returns an Observable object, which provides a declarative API for subscribing to and operating on events. It's an alternative to addEventListener() callbacks.

Status

Limited availability

MDN documentation

No MDN documentation found. You can search for the feature on MDN. If you believe that MDN has no documentation about this feature, you can open an issue on MDN's GitHub repository.

Browser support

  • Chrome 135 Released on 2025-04-01
  • Chrome Android 135 Released on 2025-04-01
  • Edge 135 Released on 2025-04-04
  • Firefox Vendor position : unknown (concerns: complexity, venue)
  • Firefox for Android Vendor position : unknown (concerns: complexity, venue)
  • Safari Vendor position : support (concerns: venue)
  • Safari on iOS Vendor position : support (concerns: venue)