The MozScrolledAreaChanged event is fired when the document view has been scrolled or resized.

Note: While you can poll the values of document.scrollWidth and document.scrollHeight to watch for changes to the document size, reading these properties can trigger document reflow, which can make them computationally expensive. This event, introduced in Gecko 1.9.2, is fired whenever either or both of these values change.

Specification Mozilla specific
Interface UIEvent
Bubbles Yes
Cancelable Yes
Target DefaultView, Document
Default Action None


Property Type Description
targetRead only EventTarget The event target (the topmost target in the DOM tree).
typeRead only DOMString The type of event.
bubblesRead only Boolean Whether the event normally bubbles or not.
cancelableRead only Boolean Whether the event is cancellable or not.
viewRead only WindowProxy document.defaultView (window of the document)
detailRead only long (float) 0.
widthRead only long (int) The width of the visible region of the document.
heightRead only long (int) The height of the visible region of the document.
xRead only long (int) The X coordinate of the left edge of the visible region of the document.
yRead only long (int) The Y coordinate of the top edge of the visible region of the document.


document.addEventListener("MozScrolledAreaChanged", event => {
    // find something useful to do with those values

}, false);

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