How to create a newline in Text Node

I'm trying to add some text and a linebreak with the code below. The Text Node t is supposed to to have a linebreak between "myinput" and "ddd", but it doesn't work :(

Any ideas?

// Create a new list item when clicking on the "Add" button
function newElement() {
    var li = document.createElement("li");
    var inputText = document.getElementById("myInput").value + document.createElement("br") + "ddd" ;
    var t = document.createTextNode(inputText); // this text node is supposed to have a linebreak
    li.appendChild(t);
    li.value = document.getElementById("myValue").value;
    if (inputText === '') {
        alert("You must write something!");
    } else {
        updateLI(li);
        document.getElementById("myUL").appendChild(li);
    }
    document.getElementById("myInput").value = "";
    document.getElementById("myValue").value = "";
}

The main issue here is a Text Node can't contain any other elements and you're trying to add a br element into it. What you need is:

function newElement() {
    var li = document.createElement("li");
    var inputText = document.getElementById("myInput").value;
    li.appendChild(document.createTextNode(inputText));
    li.appendChild(document.createElement("br"));
    li.appendChild(document.createTextNode("ddd"));

    ...

Keep in mind that adding \n character to the Text Node won't help either because html "converts" all white-space to single space symbol - that is unless you use white-space: pre; CSS applied to your element (which is another option to solve your issue).