Examine source code of Rain Alarm Extension

{
  "manifest_version": 2,
  "name": "__MSG_extName__",
  "default_locale": "en",
  "description": "__MSG_extDescription__",
  "version": "1.5.8",
  "icons": {
    "128": "launcher.png"
  },
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "__MSG_extName__"
  },
  "background": {
    "page": "background.html"
  },
  "options_ui": {
    "page": "options.html",
    "chrome_style": false,
    "open_in_tab": true
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.rain-alarm.com/?from=firefox3*"
      ],
      "run_at": "document_idle",
      "js": [
        "js/inject.js"
      ]
    }
  ],
  "permissions": [
    "https://app.rain-alarm.com/*",
    "https://www.rain-alarm.com/*",
    "geolocation",
    "notifications",
    "storage"
  ],
  "web_accessible_resources": [
    "launcher.png"
  ],
  "applications": {
    "gecko": {
      "id": "rain-alarm@mdiener.de"
    }
  }
}