js get element by X Y

window.scrollY + document.querySelector('#elementId').getBoundingClientRect().top // Y

window.scrollX + document.querySelector('#elementId').getBoundingClientRect().left // X
// get the element at a certain (x, y) position
var element = document.elementFromPoint(x, y);

// for a list of elements
var elements = document.elementsFromPoint(x, y);

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