Examine source code of eBay Safe Sellers

{
  "manifest_version": 2,
  "name": "eBay Safe Sellers",
  "version": "1.0.14.4",
  "developer": {
    "name": "David Waterson"
  },
  "description": "Protects eBay buyers by flagging potential fraudulent and malicious eBay sellers based a negative feedback ratio.",
  "icons": {
    "48": "icons/ess_logo.png"
  },
  "applications": {
    "gecko": {
      "id": "ebaySafeSellers@example.com"
    }
  },
  "permissions": [
    "tabs",
    "activeTab",
    "<all_urls>",
    "storage"
  ],
  "browser_action": {
    "browser_style": false,
    "default_icon": "icons/ess_logo.png",
    "default_title": "eBay Safe Sellers",
    "default_popup": "popup/settings.html"
  },
  "web_accessible_resources": [
    "icons/ess_logo.png"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "assets/js/jquery-3.3.1.min.js",
        "assets/js/ebay.js",
        "assets/js/purify.min.js"
      ]
    }
  ]
}