// Pass this in the console, where `Demo4` is the new item reference
newReference = 'Demo4';
removeExistingItems();  // Use if you want to replace the existing item
el = document.createElement('span');
el.setAttribute('data-reference', newReference);
el.setAttribute('class', 'learnosity-item');
document.getElementById('learnosity-wrapper').appendChild(el);

itemsApp.addItems({
    "items": [{
        "reference": newReference,
        "id": newReference
    }]
});