Examine source code of Domain Guard

{
  "manifest_version": 2,
  "name": "Domain Guard",
  "version": "1.0.3",
  "description": "Domain-based navigation protection.",
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": [
    "tabs",
    "storage",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "Domain Guard",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png"
    }
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "web_accessible_resources": [
    "warning.html",
    "warning.js"
  ],
  "content_security_policy": "script-src 'self'; object-src 'self';",
  "browser_specific_settings": {
    "gecko": {
      "id": "domainguard@example.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}