getDOMElements.js

(function getDOMElements() {
    'use strict';

    const elements = document.getElementsByTagName('*');
    const len = elements.length;

    console.log(`Number of DOM elements: ${len}`);

    if (len > 500) {
        console.log('Skipping listing each element since they might hang the browser...');
        return;
    }

    Object.keys(elements).forEach((element) => {
        console.log(`${element}:`, elements[element]);
    });
})();