Examine source code of Visibility

{
  "manifest_version": 2,
  "name": "Visibility",
  "description": "Δείτε το Visibility Report κάθε ιστοτόπου που επισκέπτεστε.",
  "version": "1.0.16resigned1",
  "browser_action": {
    "default_icon": "images/visibility128.png",
    "default_popup": "popup.html",
    "default_title": "Visibility.gr"
  },
  "content_scripts": [
    {
      "matches": [
        "https://visibility.gr/*"
      ],
      "css": [
        "modify_content.css"
      ]
    }
  ],
  "icons": {
    "16": "images/visibility128.png",
    "48": "images/visibility128.png",
    "128": "images/visibility128.png"
  },
  "permissions": [
    "activeTab",
    "https://*/"
  ],
  "web_accessible_resources": [
    "manifest.json"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{94f97678-2a3a-4e30-8922-58fca1b023bb}"
    }
  }
}