Examine source code of TrustDS WebSigner

{
  "manifest_version": 2,
  "name": "TrustDS WebSigner",
  "description": "__MSG_appDesc__",
  "version": "0.16",
  "content_security_policy": "script-src 'self'; object-src 'self'; img-src 'self'",
  "homepage_url": "https://trustds.com.br/",
  "default_locale": "en",
  "browser_specific_settings": {
    "gecko": {
      "id": "trustds@fabricads.com.br",
      "strict_min_version": "57.0"
    }
  },
  "icons": {
    "16": "icons/keyicon-16.png",
    "32": "icons/keyicon-32.png",
    "48": "icons/keyicon-48.png",
    "128": "icons/keyicon-128.png"
  },
  "browser_action": {
    "default_icon": {
      "32": "icons/keyicon-32.png"
    },
    "default_popup": "home.html",
    "browser_style": false
  },
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "permissions": [
    "<all_urls>",
    "file://*/*",
    "activeTab",
    "storage",
    "downloads",
    "nativeMessaging"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://*.trustds.com.br/*",
        "file:///*"
      ],
      "js": [
        "js/jquery-3.6.0.min.js",
        "js/content_script.js"
      ],
      "run_at": "document_end",
      "all_frames": true
    }
  ]
}