Examine source code of Email Finder

{
  "manifest_version": 2,
  "name": "Email Finder",
  "description": "Email Finder helps you find email addresses on any website",
  "version": "1.0",
  "icons": {
    "16": "icons/logo-128.png",
    "48": "icons/logo-128.png",
    "128": "icons/logo-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f1a2b3c4-5d6e-4789-90ab-c1d2e3f4a5b6}"
    }
  },
  "browser_action": {
    "default_title": "Chrome Addon v3 Starter",
    "default_popup": "popup/payment.html"
  },
  "permissions": [
    "<all_urls>",
    "tabs",
    "storage",
    "scripting"
  ],
  "background": {
    "scripts": [
      "service-worker.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "js": [
        "foreground.js"
      ],
      "matches": [
        "http://*/*",
        "https://*/*"
      ]
    }
  ]
}