--- a/pixiv-fanbox-unlazy.user.js	Thu Apr 15 14:56:23 2021 +0900
+++ b/pixiv-fanbox-unlazy.user.js	Thu Apr 15 15:01:22 2021 +0900
@@ -12,29 +12,10 @@
 ;(function () {
   'use strict'
 
-  var imageUrlPrefix = 'https://downloads.fanbox.cc/images/post/'
-
-  // loop through passed nodes (or body if called without arguments)
-  var run = function (nodes) {
-    if (nodes == null) {
-      nodes = [document.body]
-    }
-
-    for (var i = 0; i < nodes.length; i++) {
-      // first try fixing itself
-      fix(nodes[i])
+  const imageUrlPrefix = 'https://downloads.fanbox.cc/images/post/'
 
-      // and then find all the links inside
-      var links = nodes[i].querySelectorAll(`[href^="${imageUrlPrefix}"]`)
-
-      for (var j = 0; j < links.length; j++) {
-        fix(links[j])
-      }
-    }
-  }
-
-  var fix = function (link) {
-    var href = link.href
+  const fix = function (link) {
+    const href = link.href
 
     // basic sanity check
     if (typeof href !== 'string' || !href.startsWith(imageUrlPrefix)) {
@@ -53,14 +34,33 @@
     link.innerHTML = `<img style="width: 100%;" src="${href}" />`
   }
 
-  var onMutate = function (mutations) {
-    for (var mutation in mutations) {
+  const onMutate = function (mutations) {
+    for (const mutation in mutations) {
       run(mutation.addedNodes)
     }
   }
 
+  // loop through passed nodes (or body if called without arguments)
+  const run = function (nodes) {
+    if (nodes == null) {
+      nodes = [document.body]
+    }
+
+    for (let i = 0; i < nodes.length; i++) {
+      // first try fixing itself
+      fix(nodes[i])
+
+      // and then find all the links inside
+      const links = nodes[i].querySelectorAll(`[href^="${imageUrlPrefix}"]`)
+
+      for (let j = 0; j < links.length; j++) {
+        fix(links[j])
+      }
+    }
+  }
+
   // the observer
-  var observer = new window.MutationObserver(onMutate)
+  const observer = new window.MutationObserver(onMutate)
 
   // start the observer
   observer.observe(document, { childList: true, subtree: true })