To append HTML string to the DOM with JavaScript, we create an element with the HTML inside.
For instance, we write
const child = document.createElement("div");
child.innerHTML = str;
child = child.firstChild;
document.getElementById("test").appendChild(child);
to create the div with createElement.
And then we set its innerHTML property to the HTML string str.
Next, we get the first chilld of the div with firstChild.
And then we call appendChild to append the child as the last child o the element with ID test.
