document.addEventListener("DOMContentLoaded", function(event) { 
    var all_selects = document.getElementsByTagName('select');
    for (var i in all_selects) {
        if (!all_selects.hasOwnProperty(i)) {
            continue;
        }
        var xsel = all_selects[i];
        var xvalue = xsel.dataset.value;
        //console.log('Value of %o = %o', xsel, xvalue);
        // Walk all options, compare to desired value and set if matches
        for (var o in xsel.options) {
            if (xsel.options[o].value == xvalue) {
                xsel.selectedIndex = o;
                break;
            }
        }
    }
});