Examine source code of RTL Quickpay

{
  "manifest_version": 2,
  "name": "RTL Quickpay",
  "description": "RTL Quick Lightning payments.",
  "version": "0.0.6",
  "author": "Shahana",
  "icons": {
    "16": "./images/Helmet16.png",
    "48": "./images/Helmet48.png",
    "128": "./images/Helmet128.png"
  },
  "background": {
    "persistent": true,
    "scripts": [
      "./scripts/browser-polyfill.js",
      "./scripts/background.js"
    ]
  },
  "browser_action": {
    "default_icon": "./images/Helmet16.png",
    "default_title": "RTL Quickpay",
    "default_popup": "./index.html"
  },
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "./scripts/browser-polyfill.js",
        "./scripts/content.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    }
  ],
  "permissions": [
    "storage",
    "activeTab",
    "contextMenus"
  ],
  "applications": {
    "gecko": {
      "id": "shahana.farooqui@rtl.com",
      "strict_min_version": "57.0"
    }
  }
}