code:

// ==UserScript==
// @name        Fix videos - somethingawful.com
// @namespace   Violentmonkey Scripts
// @match       https://forums.somethingawful.com/*
// @version     1.0
// @author      -
// @description 2/27/2020, 11:56:31 PM
// ==/UserScript==

const fixVideos = setTimeout(function(){
  var videos = document.getElementsByTagName('video');
  for(var i = 0; i < videos.length; i++){
    videos[i].removeAttribute('loop');
    videos[i].controls = true;
    videos[i].pause();
    videos[i].currentTime = 0;
    videos[i].volume = 1;
    videos[i].muted = false;
  }
}, 500);