add: if (hintLabel == null) break; 
context: function xformsStyleLoosesFocus(event) {    var target = getEventTarget(event);    if (!xformsArrayContains(target.className.split(" "), "xforms-control"))        target = target.parentNode;    var hintLabel = target;    while (true) {        if (xformsArrayContains(hintLabel.className.split(" "), "xforms-hint-active") && hintLabel.htmlFor == target.id) {            xformsRemoveClass(hintLabel, "xforms-hint-active");            xformsAddClass(hintLabel, "xforms-hint");            break;        }        hintLabel = hintLabel.nextSibling;    }}
meta: 9823	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9823/edb637e3c9fc06ec6b4bc653bc1e3c0c3345281f/xforms-style.js/clean/src/examples/web/config/theme/javascript/xforms-style.js