禁用网页中的突出显示

I did an experiment like this:

我做了这样的实验:

<div onclick="clickfunc(this)"> highlightME </div>
<div> ooo blablabla highlightME ooo highlightME ooo highlightME ooo</div>

<script language=javascript>

    function clickfunc(obj) {
        var t = $(obj).text();
        doSearch(t);
    }

    function doSearch(text) {
        if (window.find && window.getSelection) {
            document.designMode = "on";
            // var sel = window.getSelection();
            // console.log(sel);
            // sel.collapse(document.body, 0);

            while (window.find(text)) {
                document.execCommand("HiliteColor", false, "yellow");
                //sel.collapseToEnd();
            }
            document.designMode = "off";
        }
        else if (document.body.createTextRange) {
            var textRange = document.body.createTextRange();
            while (textRange.findText(text)) {
                textRange.execCommand("BackColor", false, "yellow");
                textRange.collapse(false);
            }
        }
    }
</script>
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