Examine source code of SynthPass

{
  "name": "SynthPass",
  "short_name": "SynthPass",
  "description": "High-security password synthesizer",
  "omnibox": {
    "keyword": "src"
  },
  "version": "0.2.9",
  "manifest_version": 3,
  "icons": {
    "16": "img/icon16.png",
    "48": "img/icon48.png",
    "128": "img/icon128.png"
  },
  "permissions": [
    "storage",
    "activeTab",
    "scripting",
    "alarms",
    "contextMenus",
    "history"
  ],
  "content_security_policy": {
    "extension_pages": "default-src 'self'; img-src 'self' data:; style-src 'self'; frame-src 'self' https://* http://*"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_icon": {
      "16": "img/icon16.png",
      "48": "img/icon48.png",
      "128": "img/icon128.png"
    },
    "default_title": "SynthPass",
    "default_popup": "html/popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "synthpass@passlok.com"
    }
  }
}