js/mod/recent_posts.js: polyfill AbortSignal.any, add load wrapper, silence AbortSignal DOMException warn

js/mod/recent_posts.js

@@ -2,6 +2,27 @@
  * Implements live-reloading on the recent posts mod page.
  */
 (() => {
+    if (AbortSignal.any === undefined) {
+        AbortSignal.any = function (signals) {
+            const controller = new AbortController()
+            const callbacks = []
+
+            const abortFn = () => {
+                for (const signal of signals) {
+                    signal.removeEventListener("abort", abortFn)
+                }
+                controller.abort()
+            }
+
+            for (const signal of signals) {
+                signal.addEventListener("abort", abortFn)
+            }
+
+            return controller.signal
+        }
+    }
+
+    const scriptFn = () => {
         const kLocationPath = location.href.slice(location.origin.length)
         if (/^\/mod\.php\?\/recent\/\d+$/.test(kLocationPath)) {
             const loadIntFromStorage = key => {
@@ -38,11 +59,13 @@
             }
 
             const getPostTimestamp = post => new Date(post.lastElementChild.querySelector(".intro time").dateTime)
-        const updateRecentPosts = async () => {
+            const updateRecentPosts = () => {
                 if (liveUpdateEnabled) {
+                    fetchLatest()
+                      .then(latestPosts => {
                         const lastPost = document.body.querySelector(".post-wrapper")
                         const lastPostTs = getPostTimestamp(lastPost).getTime()
-                const posts = (await fetchLatest()).filter(post => document.getElementById(post.id) == null && getPostTimestamp(post.element).getTime() > lastPostTs)
+                        const posts = latestPosts.filter(post => document.getElementById(post.id) == null && getPostTimestamp(post.element).getTime() > lastPostTs)
                         if (posts.length > 0) {
                             const totalPosts = Array.from(document.body.querySelectorAll(".post-wrapper"))
                             for (const post of posts) {
@@ -58,6 +81,13 @@
                             makeIcon("reply")
                             liveUpdateFaviconChanged = true
                         }
+                      })
+                      .catch(error => {
+                        // XXX: Why the hell does gecko have a space at the end??
+                        if (!((error instanceof DOMException) && [ "The user aborted a request", "The operation was aborted." ].some(msg => error.message.slice(0, 26) === msg))) {
+                            throw error
+                        }
+                      })
                 }
             }
 
@@ -114,4 +144,12 @@
             pageNums.append("|")
             pageNums.append(form.div)
         }
+    }
+
+
+    if (document.readyState != "complete") {
+        window.addEventListener("load", scriptFn, { "once": true })
+    } else {
+        setTimeout(scriptFn, 1)
+    }
 })()