FB Timestamp Displayer

userscript.js

// ==UserScript==
// @name        FB Timestamp Displayer
// @namespace   Facebook
// @match       http://*.facebook.com/*
// @match       https://*.facebook.com/*
// @run-at      document-start
// @version     0.1
// @author      spixi
// @description Shows the timestamp of Facebook posts
// ==/UserScript==


//FB Timestamp Displayer
//Copyright (C) 2020 Marius Spix
//[email protected]
//
//This program is free software; you can redistribute it and/or
//modify it under the terms of the GNU Lesser General Public
//License as published by the Free Software Foundation; either
//version 3 of the License, or (at your option) any later version.
//
//This program is distributed in the hope that it will be useful,
//but WITHOUT ANY WARRANTY; without even the implied warranty of
//MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
//Lesser General Public License for more details.
//
//You should have received a copy of the GNU Lesser General Public License
//along with this program; if not, write to the Free Software Foundation,
//Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

"use strict";

document.addEventListener("DOMContentLoaded", function(){
  nodes = document.getElementsByClassName('timestampContent');
  for (i = 0; i < nodes.length; ++i) {
      node[i].innerText = new Date(parseInt(node[i].parentNode().getAttribute('data-utime'))*1000).toLocaleString();
  }
});

var observer = new MutationObserver(function(mutations) {
    mutations.forEach(function(mutation) {
      if(mutation.addedNodes.length == 1 && mutation.target.classList.contains("livetimestamp")) { //mutation.target.hasAttribute('data-utime')
        var node = mutation.addedNodes[0];			
        node.innerText = new Date(parseInt(mutation.target.getAttribute('data-utime'))*1000).toLocaleString();
      }
    });
});
observer.observe(document, { childList: true, subtree: true });