Examine source code of QRShot

{
  "manifest_version": 2,
  "name": "QRShot",
  "version": "1.2.0",
  "description": "This extension allow you to screenshot part of the webpage and scan the qrcode in it.",
  "developer": {
    "name": "ChiuYeeJay",
    "url": "https://github.com/ChiuYeeJay/QRShot"
  },
  "icons": {
    "48": "/icons/icon-48.png"
  },
  "permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "/icons/icon-32.png",
    "default_title": "qrshot"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{829307d0-586d-461e-94ce-f9d03d77feba}"
    }
  }
}