function getTitle(elem) {
    var title = "";
    for (var n = elem.firstChild; n; n = n.nextSibling)
    {
        if (n.nodeType === Node.ELEMENT_NODE)
        {
            if (n.localName === "br")
            {
                title += '\nThe rest goes here';
            }
        }
        else if (n.nodeType === Node.TEXT_NODE)
        {
            title += n.nodeValue;
        }
    }
    return title;
}

function ReplChapterTitleBRs() {
    var hs = document.getElementsByTagName("h2");
    for (var i = 0; i < hs.length; ++i) {
        var h = hs[i];
        h.title = getTitle(h);
    }
}

if (window.addEventListener)
        window.addEventListener('load',ReplChapterTitleBRs,false);