Javascript page profiler

elems = document.querySelectorAll('div')
l = [];
for (var i = 0, len = elems.length; i < len; i++) {
    if (elems[i].offsetTop != 0) {
        l.push(elems[i]);
    };
};
// l.sort((a, b) => ((a.scrollHeight * a.scrollWidth) < (b.scrollHeight * b.scrollWidth)) ? 1 : -1);
// for (var i=0, len=l.length; i < len; i++) {
//     console.log(l[i].offsetTop, l[i].offsetLeft, l[i].offsetHeight, l[i].offsetWidth, l[i])
// };

function f() {
    for (var i=0, len=elems.length; i<len; i++){
        if (elems[i].getBoundingClientRect().y != 0) {
            return elems[i];
        };
    };
};

var x = f()

var divs = []
for (var i=0, len=x.length; i<len; i++){
    if (x[i].nodeName == 'DIV') {
        divs.push(x[i])
    };
};