Examine source code of Privacy Score Meter

{
  "manifest_version": 2,
  "name": "Privacy Score Meter",
  "version": "1.0",
  "description": "Rate website safety and cleanliness.",
  "permissions": [
    "tabs",
    "<all_urls>"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icon.png"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{979e68c1-b469-452f-a121-2f6d1f4e118e}"
    }
  }
}