Examine source code of Sapphire Browser Helper

{
  "name": "Sapphire Browser Helper",
  "description": "Supports the use of Sapphire Point of Sale",
  "version": "1.0.0",
  "manifest_version": 2,
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "16": "images/icons/gem_16.png",
    "48": "images/icons/gem_48.png",
    "128": "images/icons/gem_128.png"
  },
  "permissions": [
    "tabs",
    "*://*/*"
  ]
}