With CSS overscroll behavior property developers can prevent user-agent defined default boundary actions. Overscroll affordance (e.g. rubber-banding or glow effect), pull to refresh, and history swipe navigation are examples of default boundary actions.
Overscroll behavior property lets developers to prevent default aformentioned boundary actions. However in order to implement customized behaviors, they still need to register a combination of scroll, touch, wheel event listeners to find out when overscrolling has started and trigger their customized scroll boundary behavior. This approach has the following disadvantages/limitations:
- Needs to be implemented for different methods of scrolling separately (touchscreen, wheel, keyboard, etc.)
- If the developer wants to trigger overscroll animation at the end of the scroll gesture, touchend event listener can be used for touchscreen scrolling. However for other methods of scrolling (e.g. touchpad scrolling) this won’t be possible using the currently existing events.
- In presence of a cross origin iframe the embedder that might get scrolled might not get the touchmove/wheel events at all.
Here is the full proposed API and specification.