1. Passive event listeners

    Event listeners created with the `passive: true` option cannot cancel (`preventDefault()`) the events they receive. Primarily intended to be used with touch events and `wheel` events. Since they cannot prevent scrolls, passive event listeners allow the browser to perform optimizations that result in smoother scrolling.

  2. element api: `mousewheel` event

  3. element api: `wheel` event

  4. eventtarget api: addeventlistener: form with `options` object supported (third parameter can be either options or a `boolean`, for backwards compatibility): `options.passive` parameter defaults to `true` for `wheel` and `mousewheel` events

  5. wheelevent api

  6. wheelevent api: deltamode

  7. wheelevent api: deltax

  8. wheelevent api: deltay

  9. wheelevent api: deltaz

  10. wheelevent api: pinch-to-zoom maps to `wheelevent` + `ctrl` key.

  11. wheelevent api: wheeldelta

  12. wheelevent api: wheeldeltax

  13. wheelevent api: wheeldeltay

  14. wheelevent api: `wheelevent()` constructor