in static/assets/js/bootstrap.bundle.js [2283:2310]
function getPopperOffsets(popper, referenceOffsets, placement) {
placement = placement.split('-')[0];
// Get popper node sizes
var popperRect = getOuterSizes(popper);
// Add position, width and height to our offsets object
var popperOffsets = {
width: popperRect.width,
height: popperRect.height
};
// depending by the popper placement we have to compute its offsets slightly differently
var isHoriz = ['right', 'left'].indexOf(placement) !== -1;
var mainSide = isHoriz ? 'top' : 'left';
var secondarySide = isHoriz ? 'left' : 'top';
var measurement = isHoriz ? 'height' : 'width';
var secondaryMeasurement = !isHoriz ? 'height' : 'width';
popperOffsets[mainSide] = referenceOffsets[mainSide] + referenceOffsets[measurement] / 2 - popperRect[measurement] / 2;
if (placement === secondarySide) {
popperOffsets[secondarySide] = referenceOffsets[secondarySide] - popperRect[secondaryMeasurement];
} else {
popperOffsets[secondarySide] = referenceOffsets[getOppositePlacement(secondarySide)];
}
return popperOffsets;
}