Examine source code of Password Manager

{
  "manifest_version": 2,
  "name": "Password Manager",
  "version": "2.1",
  "description": "A simple, secure password manager with a dynamic field picker.",
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "permissions": [
    "storage",
    "notifications",
    "tabs",
    "clipboardWrite",
    "*://*.voicelinq.com/*"
  ],
  "background": {
    "scripts": [
      "crypto-helpers.js",
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content-script.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{9a77ee27-c324-4dc4-9c47-8cbf65e403cc}"
    }
  }
}