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. WebAssembly Bulk Memory Operations

    An extension to WebAssembly adding bulk memory operations and conditional segment initialization

  3. eventtarget api: addeventlistener: form with `options` object supported (third parameter can be either options or a `boolean`, for backwards compatibility): `options.passive` parameter

  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 `touchstart` and `touchmove` events

  5. 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