First working version of extension

README.md

@@ -0,0 +1,12 @@
+# Potatoes Emojis Firefox WebExtension
+
+**This add-on replaces latest noto-emoji from Google with old "potatoes"(or "worms" or whatever you call it...) emojis from Android 6.0.1 on the Google website Messages for web.**
+
+## What it does
+
+This extension just includes:
+
+* a content script, "replace-emojis.js", that is injected into any pages under "messages.android.com" or any of its subdomains
+
+The content script intercept HTTP requests to the CDN hosting latest Noto emojis (ssl.gstatic.com) and redirect these requests to an archived version of the noto-emoji Github repository (commit 914c9ecb9d5e6d96c972c8df577cc6a36d162ece).
+

icons/LICENSE

@@ -0,0 +1 @@
+The icon "sleuth-or-spy_1f575" is taken from the Google Noto Emoji project, and is used under the terms of the Apache License 2.0: https://www.apache.org/licenses/LICENSE-2.0

manifest.json

@@ -0,0 +1,23 @@
+{
+    "description": "Replace latest noto-emoji from Google with old \"potatoes\"(or \"worms\" or whatever you call it...) emojis from Android 6.0.1 on the Google website Messages for web",
+    "manifest_version": 2,
+    "name": "Potatoes Emojis",
+    "version": "1.0",
+
+    "permissions": [
+        "webRequest",
+        "webRequestBlocking",
+        "*://messages.android.com/*",
+        "*://ssl.gstatic.com/*"
+    ],
+
+    "background": {
+        "scripts": ["replace-emojis.js"]
+    },
+
+    "icons": {
+        "48": "icons/sleuth-or-spy_1f575_48.png",
+        "96": "icons/sleuth-or-spy_1f575_96.png",
+        "128": "icons/sleuth-or-spy_1f575_128.png"
+    }
+}

replace-emojis.js

@@ -0,0 +1,14 @@
+var pattern = "*://ssl.gstatic.com/dynamite/emoji/*";
+
+function redirect(requestDetails) {
+    // Replace origin URL with archived Google Emoji equivalent from noto-emoji repository
+    return {
+        redirectUrl: requestDetails.url.replace("ssl.gstatic.com/dynamite/emoji", "raw.githubusercontent.com/googlei18n/noto-emoji/914c9ecb9d5e6d96c972c8df577cc6a36d162ece")
+    };
+}
+
+browser.webRequest.onBeforeRequest.addListener(
+    redirect,
+    {urls: [pattern], types:["image"]},
+    ["blocking"]
+);