public/javascript/libs/wysihtml5-0.3.0.js
function splitDataNode(node, index) {
        var newNode = node.cloneNode(false);
        newNode.deleteData(0, index);
        node.deleteData(index, node.length - index);
        insertAfter(newNode, node);
        return newNode;
    }
function splitDataNode(node, index) {
        var newNode = node.cloneNode(false);
        newNode.deleteData(0, index);
        node.deleteData(index, node.length - index);
        insertAfter(newNode, node);
        return newNode;
    }
Note that we cannot use splitText() because it is bugridden in IE 9.