Examine source code of Goal Tracker v2

{
  "manifest_version": 2,
  "name": "Goal Tracker",
  "version": "1.0",
  "description": "Track your daily goals and progress.",
  "permissions": [
    "storage"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icons/icon.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{32957759-19ba-4182-838c-eea656e40512}"
    }
  }
}