List of valid HTML Elements

script.js

// Run this on https://developer.mozilla.org/en/docs/Web/HTML/Element
var tags = [], nodeList = document.querySelectorAll('td a code'); 
for (i in nodeList) {
    if ((nodeList[i].innerText) && (nodeList[i].innerText.indexOf('<') > -1)) {
        var tag = nodeList[i].innerText.replace('<','"').replace('>','"');
        if (tags.indexOf(tag) == -1) {
            tags.push(tag);
        }
    }
}
console.log(tags.join(','));