Examine source code of Referral Traffic Tracker

{
  "manifest_version": 2,
  "name": "Referral Traffic Tracker",
  "version": "1.1",
  "description": "Track and analyze website traffic from referral sources with filtering and export options.",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "storage",
    "tabs",
    "downloads",
    "http://*/*",
    "https://*/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icons/logo_64.png"
  },
  "icons": {
    "64": "icons/logo_64.png"
  },
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{26181992-84f0-4030-97e1-d23275b7bb33}"
    }
  }
}