in static/js/popper.js [186:213]
function getOffsetParent(element) {
if (!element) {
return document.documentElement;
}
var noOffsetParent = isIE(10) ? document.body : null;
// NOTE: 1 DOM access here
var offsetParent = element.offsetParent;
// Skip hidden elements which don't have an offsetParent
while (offsetParent === noOffsetParent && element.nextElementSibling) {
offsetParent = (element = element.nextElementSibling).offsetParent;
}
var nodeName = offsetParent && offsetParent.nodeName;
if (!nodeName || nodeName === 'BODY' || nodeName === 'HTML') {
return element ? element.ownerDocument.documentElement : document.documentElement;
}
// .offsetParent will return the closest TD or TABLE in case
// no offsetParent is present, I hate this job...
if (['TD', 'TABLE'].indexOf(offsetParent.nodeName) !== -1 && getStyleComputedProperty(offsetParent, 'position') === 'static') {
return getOffsetParent(offsetParent);
}
return offsetParent;
}