Examine source code of TaskMate

{
  "manifest_version": 2,
  "name": "TaskMate",
  "version": "1.0",
  "description": "Easily manage your tasks and todo items via toolbar popup.",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icon.png"
    }
  },
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{86d35593-a1d7-4a2b-ad7a-3205b888e4c5}"
    }
  }
}