Examine source code of Weather Checker

{
  "manifest_version": 2,
  "name": "Weather Addons",
  "version": "1.1resigned1",
  "description": "A Weather Checker Addons",
  "icons": {
    "32": "icons/icon1.jpeg",
    "48": "icons/icon2.jpeg",
    "96": "icons/icon2.jpeg"
  },
  "author": "Azharul Islam",
  "applications": {
    "gecko": {
      "id": "weather@addons",
      "strict_min_version": "42.0",
      "strict_max_version": "50.*"
    }
  },
  "browser_action": {
    "default_icon": {
      "16": "icons/icon1.jpeg"
    },
    "default_popup": "index.html"
  },
  "permissions": [
    "webRequest"
  ]
}