Examine source code of Trust QR Code

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "name": "Trust QR Code",
  "description": "This Extension allow the user to quickly create trust QR Codes with the current url",
  "version": "1.0.1",
  "icons": {
    "16": "icon16.png",
    "64": "icon64.png",
    "128": "icon128.png"
  },
  "browser_action": {
    "default_icon": {
      "19": "icon19.png",
      "38": "icon38.png"
    },
    "default_title": "Trust Create QR Code",
    "default_popup": "popup.html"
  },
  "permissions": [],
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}