JSFiddle - React, Tailwind, and code Playground

HTML

<div id="id1" name="name1"></div>
<div id="id2" name="name1"></div>
<div id="id3"></div>
<div id="id4" name="name4"></div>
<div name="name5"></div>

JavaScript

var htmlCollection = document.getElementsByTagName("div");
console.log(htmlCollection.__proto__);
for (var prop in htmlCollection) {
    console.log(prop);
}