Downgraded manifest for Firefox compatibility: v3 -> v2

src/manifest.json

@@ -2,13 +2,8 @@
   "name": "RSS Viewer",
   "description": "An easy way to render RSS feeds directly in your browser",
   "version": "0.1.1",
-  "manifest_version": 3,
-  "action": {
-    "default_icon": {
-      "16": "assets/icon16.png",
-      "48": "assets/icon48.png",
-      "128": "assets/icon128.png"
-    },
+  "manifest_version": 2,
+  "browser_action": {
     "default_title": "Feed Viewer",
     "default_popup": "popup/index.html"
   },
@@ -18,7 +13,7 @@
     "128": "assets/icon128.png"
   },
   "background": {
-    "service_worker": "background.ts"
+    "scripts": ["background.ts"]
   },
   "content_scripts": [
     {
@@ -28,12 +23,9 @@
     }
   ],
   "web_accessible_resources": [
-    {
-      "resources": ["viewer/index.html"],
-      "matches": ["*://*/*"]
-    }
+    "viewer/index.html"
   ],
   "permissions": [
-    "activeTab", "identity", "storage", "tabs", "webNavigation"
+    "activeTab", "storage", "<all_urls>", "webNavigation"
   ]
 }