A userscript that adds upvotes and downvotes to reddit comments (similar to RedditEnhancementSuite)

upvoteDownvote.js

function formatComments() {
  var commments = document.querySelectorAll("div[data-ups]");

  for (var i = 0, l = commments.length; i < l; ++i) {
    var data = commments[i];
    var likes = data.getAttribute("data-ups");
    var dislikes = data.getAttribute("data-downs");
    if (likes !== undefined && dislikes !== undefined) {
      var post = data.querySelector(".entry.unvoted");
      if (post && !post.querySelector(".wooo")) {
        var uad = post.querySelectorAll(".noncollapsed>.tagline>span[class$='likes']");
        if (!uad || !uad.length) {
          continue;
        }
        var p = uad[0].parentNode;
        var cc = document.createElement("span");
        cc.innerHTML = "(<span class='wooo' style='color:#7e6ff3'>" + dislikes + "</span> | <span style='color:orangered'>" + likes + "</span>)&nbsp;";
        cc.style.display = "inline";
        var q = p.children;
        p.insertBefore(cc, q[q.length-2]);
        if (cc.previousSibling && cc.previousSibling.style) {
          cc.previousSibling.style.display = "none";
        }
      }
    }
  }
}
var ca = document.querySelector(".commentarea");
if (ca) {
  formatComments();
  var observer = new MutationObserver(function(mutations) {
    mutations.forEach(function(mutation) {
      if (mutation.addedNodes && mutation.addedNodes.length && mutation.addedNodes[0].className) {
        formatComments();
      }
    });
  });
  window.setTimeout(function() {
    formatComments();
    observer.observe(ca, {
      subtree: true,
      childList: true
    });
  }, 200);
}