Remove propagation of mouse wheel events to parent iframe.

When an iframe does not handle a mouse wheel event it is currently dispatched to the parent iframe. Mouse wheel events are unique in this dispatching aspect and other vendors FireFox and Microsoft both don't dispatch the event to the parent iframe. This request is to make Chrome match FF and Edge. Some public discussion has happened on Fireכox's bug where a web developer asked Mozilla to implement similar behavior to chrome.


The request by a web developer for FireFox to match Chrome's behavior raises some concern that people in fact are relying on this. Ideally this should be removed it because it interferes with the separation of Scrolling events from MouseWheel events. Right now mouse wheel events are conflated with scroll events; in preparation of passive event listeners for wheel we need to decouple them.



Status in Chromium


Enabled by default (launch bug) in:

  • Chrome for desktop release 51
  • Chrome for Android release 51
  • Android WebView release 51
  • Opera release 38
  • Opera for Android release 38

Consensus & Standardization

  • Public support
  • No public signals
  • No public signals
  • Mixed signals


Last updated on 2017-06-14